Free Standard AU & NZ Shipping For All Book Orders Over $80!
Register      Login
Functional Plant Biology Functional Plant Biology Society
Plant function and evolutionary biology
Shopping Cart: ( empty )
You are here: Home > Journals > FP > FP15025
REVIEW
Contents Vol 42(10)

Genetic approaches to enhancing nitrogen-use efficiency (NUE) in cereals: challenges and future directions

Trevor Garnett A B , Darren Plett A B C , Sigrid Heuer A B and Mamoru Okamoto A B
+ Author Affiliations
- Author Affiliations

A Australian Centre for Plant Functional Genomics, School of Agriculture Food and Wine, University of Adelaide, Adelaide, SA 5064, Australia.

B School of Agriculture, Food and Wine, University of Adelaide, Adelaide, SA 5064, Australia.

C Corresponding author. Email: darren.plett@acpfg.com.au

Functional Plant Biology 42(10) 921-941 https://doi.org/10.1071/FP15025
Submitted: 2 February 2015  Accepted: 24 June 2015   Published: 3 August 2015

Abstract

Over 100 million tonnes of nitrogen (N) fertiliser are applied globally each year to maintain high yields in agricultural crops. The rising price of N fertilisers has made them a major cost for farmers. Inefficient use of N fertiliser leads to substantial environmental problems through contamination of air and water resources and can be a significant economic cost. Consequently, there is considerable need to improve the way N fertiliser is used in farming systems. The efficiency with which crops use applied N fertiliser – the nitrogen-use efficiency (NUE) – is currently quite low for cereals. This is the case in both high yielding environments and lower yielding environments characteristic of cereal growing regions of Australia. Multiple studies have attempted to identify the genetic basis of NUE, but the utility of the results is limited because of the complex nature of the trait and the magnitude of genotype by environment interaction. Transgenic approaches have been applied to improve plant NUE but with limited success, due, in part, to a combination of the complexity of the trait but also due to lack of accurate phenotyping methods. This review documents these two approaches and suggests future directions in improving cereal NUE with a focus on the Australian cereal industry.

Additional keywords: biotechnology, fertiliser, metabolism.


References

ABARES (2013) ‘Agricultural commodity statistics 2013.’ (Australian Bureau of Agricultural and Resource Economics and Sciences: Canberra)

Abiko T, Wakayama M, Kawakami A, Obara M, Kisaka H, Miwa T, Aoki N, Ohsugi R (2010) Changes in nitrogen assimilation, metabolism, and growth in transgenic rice plants expressing a fungal NADP(H)-dependent glutamate dehydrogenase (gdhA). Planta 232, 299–311.
| Changes in nitrogen assimilation, metabolism, and growth in transgenic rice plants expressing a fungal NADP(H)-dependent glutamate dehydrogenase (gdhA).Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXnsFGru78%3D&md5=8ce9a34451739bab3cd193ed0db619bdCAS | 20443025PubMed |

ABS (2014) 4627.0 – Land Management and Farming in Australia, 2012–13. Available at http://www.abs.gov.au/ausstats/abs@.nsf/mf/4627.0 [Verified 9 July 2015]

Agrama HAS, Zakaria AG, Said FB, Tuinstra M (1999) Identification of quantitative trait loci for nitrogen use efficiency in maize. Molecular Breeding 5, 187–195.
| Identification of quantitative trait loci for nitrogen use efficiency in maize.Crossref | GoogleScholarGoogle Scholar |

Ahn JH, Choi Y, Kwon YM, Kim SG, Choi YD, Lee JS (1996) A novel extensin gene encoding a hydroxyproline-rich glycoprotein requires sucrose for its wound-inducible expression in transgenic plants. The Plant Cell 8, 1477–1490.
| A novel extensin gene encoding a hydroxyproline-rich glycoprotein requires sucrose for its wound-inducible expression in transgenic plants.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK28XlvFOlu7s%3D&md5=71eebebd1c1c560673fe2fe50f7080a7CAS | 8837503PubMed |

Ameziane R, Bernhard K, Lightfoot D (2000) Expression of the bacterial gdhA gene encoding a NADPH glutamate dehydrogenase in tobacco affects plant growth and development. Plant and Soil 221, 47–57.
| Expression of the bacterial gdhA gene encoding a NADPH glutamate dehydrogenase in tobacco affects plant growth and development.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3cXlslyns74%3D&md5=cdd61fa747b821a921081c48351f930fCAS |

An D, Su J, Liu Q, Zhu Y, Tong Y, Li J, Jing R, Li B, Li Z (2006) Mapping QTLs for nitrogen uptake in relation to the early growth of wheat (Triticum aestivum L.). Plant and Soil 284, 73
| Mapping QTLs for nitrogen uptake in relation to the early growth of wheat (Triticum aestivum L.).Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XntF2jur4%3D&md5=bbab3ba40a09bcb00b352c10fd2034ebCAS |

Anbessa Y, Juskiw P, Good A, Nyachiro J, Helm J (2009) Genetic variability in nitrogen use efficiency of spring barley. Crop Science 49, 1259–1269.
| Genetic variability in nitrogen use efficiency of spring barley.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXpvVyrtrw%3D&md5=3df3d419ece9d4b59dc49af917d7b0c3CAS |

Anbessa Y, Juskiw P, Good A, Nyachiro J, Helm J (2010) Selection efficiency across environments in improvement of barley yield for moderately low nitrogen environments. Crop Science 50, 451–457.
| Selection efficiency across environments in improvement of barley yield for moderately low nitrogen environments.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXksl2htbk%3D&md5=6c5f71a73d35888152b142ff0727caa4CAS |

Aslam M, Travis RL, Huffaker RC (1993) Comparative induction of nitrate and nitrite uptake and reduction systems by ambient nitrate and nitrite in intact roots of barley (Hordeum vulgare L) seedlings. Plant Physiology 102, 811–819.

Baker SS, Wilhelm KS, Thomashow MF (1994) The 5ʹ-region of Arabidopsis thaliana cor15a has cis-acting elements that confer cold-, drought- and ABA-regulated gene expression. Plant Molecular Biology 24, 701–713.
| The 5ʹ-region of Arabidopsis thaliana cor15a has cis-acting elements that confer cold-, drought- and ABA-regulated gene expression.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2cXkslCqtrw%3D&md5=c372946de9c62b982c22b57aded6a5bbCAS | 8193295PubMed |

Bänziger M, Betrán FJ, Lafitte HR (1997) Efficiency of high-nitrogen selection environments for improving maize for low-nitrogen target environments. Crop Science 37, 1103–1109.
| Efficiency of high-nitrogen selection environments for improving maize for low-nitrogen target environments.Crossref | GoogleScholarGoogle Scholar |

Barbottin A, Lecomte C, Bouchard C, Jeuffroy M-H (2005) Nitrogen remobilization during grain filling in wheat. Crop Science 45, 1141–1150.
| Nitrogen remobilization during grain filling in wheat.Crossref | GoogleScholarGoogle Scholar |

Bauwe H, Hagemann M, Fernie AR (2010) Photorespiration: players, partners and origin. Trends in Plant Science 15, 330–336.
| Photorespiration: players, partners and origin.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXntV2itr4%3D&md5=7dece9b2aa7633227df2295a12707af6CAS | 20403720PubMed |

Beatty PH, Good AG (2011) Future prospects for cereals that fix nitrogen. Science 333, 416–417.
| Future prospects for cereals that fix nitrogen.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXhtFyltLbE&md5=e0b1185c924dd2b04572c1b222163453CAS | 21778391PubMed |

Beatty PH, Anbessa Y, Juskiw P, Carroll RT, Wang J, Good AG (2010) Nitrogen use efficiencies of spring barley grown under varying nitrogen conditions in the field and growth chamber. Annals of Botany 105, 1171–1182.
| Nitrogen use efficiencies of spring barley grown under varying nitrogen conditions in the field and growth chamber.Crossref | GoogleScholarGoogle Scholar | 20308048PubMed |

Belhaj K, Chaparro-Garcia A, Kamoun S, Nekrasov V (2013) Plant genome editing made easy: targeted mutagenesis in model and crop plants using the CRISPR/Cas system. Plant Methods 9, 39
| Plant genome editing made easy: targeted mutagenesis in model and crop plants using the CRISPR/Cas system.Crossref | GoogleScholarGoogle Scholar | 24112467PubMed |

Bertin P, Gallais A (2000) Genetic variation for nitrogen use efficiency in a set of recombinant maize inbred lines I. Agrophysiological results. Maydica 45, 53–66.

Bertin P, Gallais A (2001) Genetic variation for nitrogen use efficiency in a set of recombinant inbred lines II – QTL detection and coincidences. Maydica 46, 53–68.

Bezant H, Laurie DA, Pratchett N, Chojecki J, Kearsey MJ (1997) Mapping of QTL controlling NIR predicted hot water extract and grain nitrogen content in a spring barley cross using marker-regression. Plant Breeding 116, 141–145.
| Mapping of QTL controlling NIR predicted hot water extract and grain nitrogen content in a spring barley cross using marker-regression.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2sXkt1WjtrY%3D&md5=606c534c5ac9122fa9e049ef53cc34c9CAS |

Bhattacharjee RB, Singh A, Mukhopadhyay SN (2008) Use of nitrogen-fixing bacteria as biofertiliser for non-legumes: prospects and challenges. Applied Microbiology and Biotechnology 80, 199–209.
| Use of nitrogen-fixing bacteria as biofertiliser for non-legumes: prospects and challenges.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXptVeqtro%3D&md5=aa5e060387e97908d31ed87a8503bedfCAS | 18600321PubMed |

Bi Y-M, Kant S, Clarke J, Gidda S, Ming F, Xu J, Rochon A, Shelp BJ, Hao L, Zhao R, Mullen RT, Zhu T, Rothstein SJ (2009) Increased nitrogen-use efficiency in transgenic rice plants over-expressing a nitrogen-responsive early nodulin gene identified from rice expression profiling. Plant, Cell & Environment 32, 1749–1760.
| Increased nitrogen-use efficiency in transgenic rice plants over-expressing a nitrogen-responsive early nodulin gene identified from rice expression profiling.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXhsFKrsrvE&md5=febcd3890a4d7f518df2cdc1e9e9db0fCAS |

Bogard M, Allard V, Brancourt-Hulmel M, Heumez E, Machet JM, Jeuffroy MH, Gate P, Martre P, Le Gouis J (2010) Deviation from the grain protein concentration-grain yield negative relationship is highly correlated to post-anthesis N uptake in winter wheat. Journal of Experimental Botany 61, 4303–4312.
| Deviation from the grain protein concentration-grain yield negative relationship is highly correlated to post-anthesis N uptake in winter wheat.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXhtlShtLbO&md5=95904d362cc8f498d2a2fa2e06bf58cdCAS | 20679251PubMed |

Bond G, Gardner IC (1957) Nitrogen fixation in non-legume root nodule plants. Nature 179, 680–681.
| Nitrogen fixation in non-legume root nodule plants.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaG2sXnvVGrtQ%3D%3D&md5=23ad8f544f2f04f4ab55a292773796beCAS |

Borrell AK, Hammer GL (2000) Nitrogen dynamics and the physiological basis of stay-green in sorghum. Crop Science 40, 1295–1307.
| Nitrogen dynamics and the physiological basis of stay-green in sorghum.Crossref | GoogleScholarGoogle Scholar |

Borrell AK, Garside AL, Fukai S, Reid DJ (1998) Season, nitrogen rate, and plant type affect nitrogen uptake and nitrogen use efficiency in rice. Australian Journal of Agricultural Research 49, 829–844.
| Season, nitrogen rate, and plant type affect nitrogen uptake and nitrogen use efficiency in rice.Crossref | GoogleScholarGoogle Scholar |

Borrell A, Hammer G, Oosterom E (2001) Stay-green: a consequence of the balance between supply and demand for nitrogen during grain filling? Annals of Applied Biology 138, 91–95.
| Stay-green: a consequence of the balance between supply and demand for nitrogen during grain filling?Crossref | GoogleScholarGoogle Scholar |

Bourion V, Rizvi S, Fournier S, de Larambergue H, Galmiche F, Marget P, Duc G, Burstin J (2010) Genetic dissection of nitrogen nutrition in pea through a QTL approach of root, nodule, and shoot variability. Theoretical and Applied Genetics 121, 71–86.
| Genetic dissection of nitrogen nutrition in pea through a QTL approach of root, nodule, and shoot variability.Crossref | GoogleScholarGoogle Scholar | 20180092PubMed |

Brauer EK, Rochon A, Bi Y-M, Bozzo GG, Rothstein SJ, Shelp BJ (2011) Reappraisal of nitrogen use efficiency in rice overexpressing glutamine synthetase1. Physiologia Plantarum 141, 361–372.
| Reappraisal of nitrogen use efficiency in rice overexpressing glutamine synthetase1.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXktlarsL8%3D&md5=77a34e515640fc8205860e1a28c01ebeCAS | 21214879PubMed |

Brutnell TP, Wang L, Swartwood K, Goldschmidt A, Jackson D, Zhu XG, Kellogg E, Van Eck J (2010) Setaria viridis: A model for C4 photosynthesis. The Plant Cell 22, 2537–2544.
| Setaria viridis: A model for C4 photosynthesis.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXhtlegsb3M&md5=1ef127615db82ceae13c9a0fe001fda4CAS | 20693355PubMed |

Burns IG (1980) Influence of the spatial distribution of nitrate and the uptake of N by plants: a review and a model for rooting depth. Journal of Soil Science 31, 155–173.
| Influence of the spatial distribution of nitrate and the uptake of N by plants: a review and a model for rooting depth.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL3cXkvFCjsbY%3D&md5=71d3ee95ff50759822a0903b9e51a6e8CAS |

Burstin J, Marget P, Huart M, Moessner A, Mangin B, Duchene C, Desprez B, Munier-Jolain N, Duc G (2007) Developmental genes have pleiotropic effects on plant morphology and source capacity, eventually impacting on seed protein content and productivity in pea. Plant Physiology 144, 768–781.
| Developmental genes have pleiotropic effects on plant morphology and source capacity, eventually impacting on seed protein content and productivity in pea.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXmvValtro%3D&md5=5d9f23c7e83afde77cf5b11550d24fc4CAS | 17449650PubMed |

Cai H, Zhou Y, Xiao J, Li X, Zhang Q, Lian X (2009) Overexpressed glutamine synthetase gene modifies nitrogen metabolism and abiotic stress responses in rice. Plant Cell Reports 28, 527–537.
| Overexpressed glutamine synthetase gene modifies nitrogen metabolism and abiotic stress responses in rice.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXitlSqt7k%3D&md5=9f10242571d92958ac4eb0d5afa9745aCAS | 19123004PubMed |

Cai H, Chen F, Mi G, Zhang F, Maurer H, Liu W, Reif J, Yuan L (2012) Mapping QTLs for root system architecture of maize (Zea mays L.) in the field at different developmental stages. Theoretical and Applied Genetics 125, 1313–1324.
| Mapping QTLs for root system architecture of maize (Zea mays L.) in the field at different developmental stages.Crossref | GoogleScholarGoogle Scholar | 22718302PubMed |

Cañas RA, Quilleré I, Gallais A, Hirel B (2012) Can genetic variability for nitrogen metabolism in the developing ear of maize be exploited to improve yield? New Phytologist 194, 440–452.
| Can genetic variability for nitrogen metabolism in the developing ear of maize be exploited to improve yield?Crossref | GoogleScholarGoogle Scholar | 22329725PubMed |

Capel J, Jarillo JA, Salinas J, Martinez-Zapater JM (1997) Two homologous low-temperature-inducible genes from Arabidopsis encode highly hydrophobic proteins. Plant Physiology 115, 569–576.
| Two homologous low-temperature-inducible genes from Arabidopsis encode highly hydrophobic proteins.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2sXntFSlsrs%3D&md5=d38c2835f5cd13feeb36684e1ec2ed26CAS | 9342870PubMed |

Cassman KG, Kropff MJ, Gaunt J, Peng S (1993) Nitrogen use efficiency of rice reconsidered: what are the key constraints? Plant and Soil 155–156, 359–362.
| Nitrogen use efficiency of rice reconsidered: what are the key constraints?Crossref | GoogleScholarGoogle Scholar |

Cassman KG, Dobermann A, Walters DT (2002) Agroecosystems, nitrogen-use efficiency, and nitrogen management. AMBIO A Journal of the Human Environment 31, 132–140.

Chardon F, Barthelemy J, Daniel-Vedele F, Masclaux-Daubresse C (2010) Natural variation of nitrate uptake and nitrogen use efficiency in Arabidopsis thaliana cultivated with limiting and ample nitrogen supply. Journal of Experimental Botany 61, 2293–2302.
| Natural variation of nitrate uptake and nitrogen use efficiency in Arabidopsis thaliana cultivated with limiting and ample nitrogen supply.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXmslSqtrk%3D&md5=2d55a1c9f81f9b094603aa60b326894fCAS | 20237091PubMed |

Charmet G, Storlie E, Oury FX, Laurent V, Beghin D, Chevarin L, Lapierre A, Perretant MR, Rolland B, Heumez E, Duchalais L, Goudemand E, Bordes J, Robert O (2014) Genome-wide prediction of three important traits in bread wheat. Molecular Breeding 34, 1843–1852.
| Genome-wide prediction of three important traits in bread wheat.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC2cXht1SlsLjO&md5=9f873f92641e1ca02d857432cb8581a9CAS |

Charpentier M, Oldroyd G (2010) How close are we to nitrogen-fixing cereals? Current Opinion in Plant Biology 13, 556–564.
| How close are we to nitrogen-fixing cereals?Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXhtlKls7zM&md5=a8b3a4d54f8f2ada317c2e385da95584CAS | 20817544PubMed |

Chen C-Z, Lv X-F, Li J-Y, Yi H-Y, Gong J-M (2012) Arabidopsis NRT1.5 is another essential component in the regulation of nitrate reallocation and stress tolerance. Plant Physiology 159, 1582–1590.
| Arabidopsis NRT1.5 is another essential component in the regulation of nitrate reallocation and stress tolerance.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38Xht1CgsL7M&md5=45a056647a27d1933bd6123af04ff68bCAS | 22685171PubMed |

Chichkova S, Arellano J, Vance CP, Hernandez G (2001) Transgenic tobacco plants that overexpress alfalfa NADH-glutamate synthase have higher carbon and nitrogen content. Journal of Experimental Botany 52, 2079–2087.

Cho Y-G, Kang H-J, Lee J-S, Lee Y-T, Lim S-J, Gauch H, Eun M-Y, McCouch SR (2007) Identification of quantitative trait loci in rice for yield, yield components, and agronomic traits across years and locations. Crop Science 47, 2403–2417.
| Identification of quantitative trait loci in rice for yield, yield components, and agronomic traits across years and locations.Crossref | GoogleScholarGoogle Scholar |

Christopher JT, Manschadi AM, Hammer GL, Borrell AK (2008) Developmental and physiological traits associated with high yield and stay-green phenotype in wheat. Australian Journal of Agricultural Research 59, 354–364.
| Developmental and physiological traits associated with high yield and stay-green phenotype in wheat.Crossref | GoogleScholarGoogle Scholar |

Clarkson DT, Hopper MJ, Jones LHP (1986) The effect of root temperature on the uptake of nitrogen and the relative size of the root system in Lolium perenne. I. Solutions containing both NH4 + and NO3 –. Plant, Cell & Environment 9, 535–545.

Clement CR, Hopper MJ, Jones LHP (1978) The uptake of nitrate by Lolium perenne from flowing culture solution. I. Effect of NO3 – concentration. Journal of Experimental Botany 29, 453–464.
| The uptake of nitrate by Lolium perenne from flowing culture solution. I. Effect of NO3 – concentration.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaE1cXkslCqs7c%3D&md5=7f078aaddc57bff6b6a499cf22caff95CAS |

Collins NC, Tardieu F, Tuberosa R (2008) Quantitative trait loci and crop performance under abiotic stress: where do we stand? Plant Physiology 147, 469–486.
| Quantitative trait loci and crop performance under abiotic stress: where do we stand?Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXnsVyhsbw%3D&md5=b068008b2071e95fa2932d85eac21f6fCAS | 18524878PubMed |

Commonwealth of Australia (2015) ‘Quarterly Update of Australia’s National Greenhouse Gas Inventory: September 2014.’ Available at http://www.environment.gov.au/climate-change/greenhouse-gas-measurement/publications/quarterly-update-australias-national-greenhouse-gas-inventory-sept-2014

Cooper HD, Clarkson DT (1989) Cycling of amino-nitrogen and other nutrients between shoots and roots in cereals – a possible mechanism for integrating shoot and root in the regulation of nutrient uptake. Journal of Experimental Botany 40, 753–762.
| Cycling of amino-nitrogen and other nutrients between shoots and roots in cereals – a possible mechanism for integrating shoot and root in the regulation of nutrient uptake.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL1MXmt12htLs%3D&md5=ef82522b0e301e4010201baef496bdd5CAS |

Cooper M, Messina CD, Podlich D, Totir LR, Baumgarten A, Hausmann NJ, Wright D, Graham G (2014) Predicting the future of plant breeding: complementing empirical evaluation with genetic prediction. Crop and Pasture Science 65, 311–336.
| Predicting the future of plant breeding: complementing empirical evaluation with genetic prediction.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC2cXotVKnsbk%3D&md5=cc0f8e7e4d3da77d694527a2dfc9a978CAS |

Coque M, Gallais A (2006) Genomic regions involved in response to grain yield selection at high and low nitrogen fertilization in maize. Theoretical and Applied Genetics 112, 1205–1220.
| Genomic regions involved in response to grain yield selection at high and low nitrogen fertilization in maize.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XjtFamtb8%3D&md5=5d89be532dc72ba01629513a8b3adc77CAS | 16552555PubMed |

Coque M, Bertin P, Hirel B, Gallais A (2006) Genetic variation and QTLs for 15N natural abundance in a set of maize recombinant inbred lines. Field Crops Research 97, 310–321.
| Genetic variation and QTLs for 15N natural abundance in a set of maize recombinant inbred lines.Crossref | GoogleScholarGoogle Scholar |

Cox MC, Qualset CO, Rains DW (1985) Genetic variation for nitrogen assimilation and translocation in wheat. II. Nitrogen assimilation in relation to grain yield and protein. Crop Science 25, 435–440.
| Genetic variation for nitrogen assimilation and translocation in wheat. II. Nitrogen assimilation in relation to grain yield and protein.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL2MXktVeku7c%3D&md5=a300307145838c3df43395f17c06ad72CAS |

Craswell ET, Godwin DC (1984) The efficiency of nitrogen fertilizers applied to cereals grown in different climates. Advances in Plant Nutrition 1, 1–55.

Crawford NM, Glass ADM (1998) Molecular and physiological aspects of nitrate uptake in plants. Trends in Plant Science 3, 389–395.
| Molecular and physiological aspects of nitrate uptake in plants.Crossref | GoogleScholarGoogle Scholar |

Crete P, Caboche M, Meyer C (1997) Nitrite reductase expression is regulated at the post-transcriptional level by the nitrogen source in Nicotiana plumbaginifolia and Arabidopsis thaliana. The Plant Journal 11, 625–634.
| Nitrite reductase expression is regulated at the post-transcriptional level by the nitrogen source in Nicotiana plumbaginifolia and Arabidopsis thaliana.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2sXjs1CltbY%3D&md5=6044047c5580a884ee43fb626ffb8cadCAS | 9161026PubMed |

Dhugga KS, Waines JG (1989) Analysis of nitrogen accumulation and use in bread and durum wheat. Crop Science 29, 1232–1239.
| Analysis of nitrogen accumulation and use in bread and durum wheat.Crossref | GoogleScholarGoogle Scholar |

Ding L, Wang KJ, Jiang GM, Biswas DK, Xu H, Li LF, Li YH (2005) Effects of nitrogen deficiency on photosynthetic traits of maize hybrids released in different years. Annals of Botany 96, 925–930.
| Effects of nitrogen deficiency on photosynthetic traits of maize hybrids released in different years.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXhtFOjsLfO&md5=5a16877405e768d593ac45d4ec1f6402CAS | 16103036PubMed |

Djennane S, Chauvin JE, Meyer C (2002a) Glasshouse behaviour of eight transgenic potato clones with a modified nitrate reductase expression under two fertilization regimes. Journal of Experimental Botany 53, 1037–1045.
| Glasshouse behaviour of eight transgenic potato clones with a modified nitrate reductase expression under two fertilization regimes.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD38XjsFagu7s%3D&md5=22149aec23d4910562c826110fbcbffeCAS | 11971915PubMed |

Djennane S, Chauvin JE, Quillere I, Meyer C, Chupeau Y (2002b) Introduction and expression of a deregulated tobacco nitrate reductase gene in potato lead to highly reduced nitrate levels in transgenic tubers. Transgenic Research 11, 175–184.
| Introduction and expression of a deregulated tobacco nitrate reductase gene in potato lead to highly reduced nitrate levels in transgenic tubers.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD38Xkt1SqtLo%3D&md5=ebbe08dc0fa8e1aba3397017ee3bd039CAS | 12054351PubMed |

Echarte L, Rothstein S, Tollenaar M (2008) The response of leaf photosynthesis and dry matter accumulation to nitrogen supply in an older and a newer maize hybrid. Crop Science 48, 656–665.
| The response of leaf photosynthesis and dry matter accumulation to nitrogen supply in an older and a newer maize hybrid.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXls1Cmtb8%3D&md5=0d89fc17ffa83a919556d7d647813bd0CAS |

Fan X, Xie D, Chen J, Lu H, Xu Y, Ma C, Xu G (2014) Over-expression of OsPTR6 in rice increased plant growth at different nitrogen supplies but decreased nitrogen use efficiency at high ammonium supply. Plant Science 227, 1–11.
| Over-expression of OsPTR6 in rice increased plant growth at different nitrogen supplies but decreased nitrogen use efficiency at high ammonium supply.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC2cXht1Oru7vM&md5=aebba40c9e57aed9605bea4608521439CAS | 25219300PubMed |

FAOSTAT (2014) Available at http://faostat3.fao.org/ (Food and Agriculture Organisation of the United Nations: Rome)

Fei HM, Chaillou S, Hirel B, Mahon JD, Vessey JK (2003) Overexpression of a soybean cytosolic glutamine synthetase gene linked to organ-specific promoters in pea plants grown in different concentrations of nitrate. Planta 216, 467–474.

Fei H, Chaillou S, Hirel B, Polowick P, Mahon JD, Vessey JK (2006) Effects of the overexpression of a soybean cytosolic glutamine synthetase gene (GS15) linked to organ-specific promoters on growth and nitrogen accumulation of pea plants supplied with ammonium. Plant Physiology and Biochemistry 44, 543–550.
| Effects of the overexpression of a soybean cytosolic glutamine synthetase gene (GS15) linked to organ-specific promoters on growth and nitrogen accumulation of pea plants supplied with ammonium.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28Xht1Cmt7rF&md5=8233abce461bc06edd6f8253cd625fdfCAS | 17067806PubMed |

Feng Y, Cao LY, Wu WM, Shen XH, Zhan XD, Zhai RR, Wang RC, Chen DB, Cheng SH (2010) Mapping QTLs for nitrogen-deficiency tolerance at seedling stage in rice (Oryza sativa L.). Plant Breeding 129, 652–656.
| Mapping QTLs for nitrogen-deficiency tolerance at seedling stage in rice (Oryza sativa L.).Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXis1Gnsg%3D%3D&md5=eceb5b582c41dc8b63c74155f4279846CAS |

Feng HM, Yan M, Fan XR, Li BZ, Shen QR, Miller AJ, Xu GH (2011) Spatial expression and regulation of rice high-affinity nitrate transporters by nitrogen and carbon status. Journal of Experimental Botany 62, 2319–2332.
| Spatial expression and regulation of rice high-affinity nitrate transporters by nitrogen and carbon status.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXlt1CltLk%3D&md5=591567b5d4abeaaa09669ff12a0f337aCAS |

Fischer RA (2011) Wheat physiology: a review of recent developments. Crop and Pasture Science 62, 95–114.
| Wheat physiology: a review of recent developments.Crossref | GoogleScholarGoogle Scholar |

Fontaine J-X, Ravel C, Pageau K, Heumez E, Dubois F, Hirel B, Le Gouis J (2009) A quantitative genetic study for elucidating the contribution of glutamine synthetase, glutamate dehydrogenase and other nitrogen-related physiological traits to the agronomic performance of common wheat. Theoretical and Applied Genetics 119, 645–662.
| A quantitative genetic study for elucidating the contribution of glutamine synthetase, glutamate dehydrogenase and other nitrogen-related physiological traits to the agronomic performance of common wheat.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXpsVeisr8%3D&md5=701c62cca09465e7557e6ae7129c8d9fCAS | 19513687PubMed |

Forde BG (2000) Nitrate transporters in plants: structure, function and regulation. Biochimica et Biophysica Acta (BBA) – Biomembranes 1465, 219–235.
| Nitrate transporters in plants: structure, function and regulation.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3cXit1Wgt74%3D&md5=0059c5aff8575e0b137f9bd5b03c156cCAS |

Forde BG, Clarkson DT (1999) Nitrate and ammonium nutrition of plants: physiological and molecular perspectives. Advances in Botanical Research 30, 1–90.

Foulkes MJ, Sylvester-Bradley R, Weightman R, Snape JW (2007) Identifying physiological traits associated with improved drought resistance in winter wheat. Field Crops Research 103, 11–24.
| Identifying physiological traits associated with improved drought resistance in winter wheat.Crossref | GoogleScholarGoogle Scholar |

Foulkes MJ, Hawkesford MJ, Barraclough PB, Holdsworth MJ, Kerr S, Kightley S, Shewry PR (2009) Identifying traits to improve the nitrogen economy of wheat: recent advances and future prospects. Field Crops Research 114, 329–342.
| Identifying traits to improve the nitrogen economy of wheat: recent advances and future prospects.Crossref | GoogleScholarGoogle Scholar |

Fraisier V, Gojon A, Tillard P, Daniel-Vedele F (2000) Constitutive expression of a putative high-affinity nitrate transporter in Nicotiana plumbaginifolia: evidence for post-transcriptional regulation by a reduced nitrogen source. The Plant Journal 23, 489–496.
| Constitutive expression of a putative high-affinity nitrate transporter in Nicotiana plumbaginifolia: evidence for post-transcriptional regulation by a reduced nitrogen source.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3cXms1ehtL8%3D&md5=62bd4633f9982e2afb6596a921cd7aa8CAS | 10972875PubMed |

Fuentes SI, Allen DJ, Ortiz-Lopez A, Hernandez G (2001) Over-expression of cytosolic glutamine synthetase increases photosynthesis and growth at low nitrogen concentrations. Journal of Experimental Botany 52, 1071–1081.
| Over-expression of cytosolic glutamine synthetase increases photosynthesis and growth at low nitrogen concentrations.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXltVeisrs%3D&md5=bdb7b3fc8a3dd67e0ec46af6e11f1fdbCAS | 11432923PubMed |

Furbank RT, Tester M (2011) Phenomics – technologies to relieve the phenotyping bottleneck. Trends in Plant Science 16, 635–644.
| Phenomics – technologies to relieve the phenotyping bottleneck.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXhsFOhu7%2FJ&md5=f85d66b2177ad74d9a28ead5d0153e7dCAS | 22074787PubMed |

Gallais A, Hirel B (2004) An approach to the genetics of nitrogen use efficiency in maize. Journal of Experimental Botany 55, 295–306.
| An approach to the genetics of nitrogen use efficiency in maize.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXms1egug%3D%3D&md5=fae4f497070c8f043925fcd23deda9cdCAS | 14739258PubMed |

Garnett TP, Rebetzke GJ (2013) Improving crop nitrogen use in dryland farming. In ‘Improving water and nutrient-use efficiency in food production systems’. pp. 123–144. (John Wiley & Sons Inc.: New York)

Garnett T, Conn V, Kaiser BN (2009) Root based approaches to improving nitrogen use efficiency in plants. Plant, Cell & Environment 32, 1272–1283.
| Root based approaches to improving nitrogen use efficiency in plants.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXhtFGhtrfF&md5=b6fca695f4e54133dae7e5488bb1c487CAS |

Garnett T, Conn V, Plett D, Conn S, Zanghellini J, Mackenzie N, Enju A, Francis K, Holtham L, Roessner U, Boughton B, Bacic A, Shirley N, Rafalski A, Dhugga K, Tester M, Kaiser BN (2013) The response of the maize nitrate transport system to nitrogen demand and supply across the lifecycle. New Phytologist 198, 82–94.
| The response of the maize nitrate transport system to nitrogen demand and supply across the lifecycle.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3sXjtlWnt7Y%3D&md5=c6b55f301d91fe099680a78ef32b2c09CAS | 23398565PubMed |

Gastal F, Lemaire G (2002) N uptake and distribution in crops: an agronomical and ecophysiological perspective. Journal of Experimental Botany 53, 789–799.
| N uptake and distribution in crops: an agronomical and ecophysiological perspective.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD38XivFSntL0%3D&md5=1d56b2c55be490544f4ad180e12a6cbfCAS | 11912222PubMed |

Gazzarrini S, Lejay T, Gojon A, Ninnemann O, Frommer WB, von Wiren N (1999) Three functional transporters for constitutive, diurnally regulated, and starvation-induced uptake of ammonium into Arabidopsis roots. The Plant Cell 11, 937–947.
| Three functional transporters for constitutive, diurnally regulated, and starvation-induced uptake of ammonium into Arabidopsis roots.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK1MXjvVajsLg%3D&md5=58927ec294832e3c06cd74bbb262d706CAS | 10330477PubMed |

Good AG, Shrawat AK, Muench DG (2004) Can less yield more? Is reducing nutrient input into the environment compatible with maintaining crop production? Trends in Plant Science 9, 597–605.
| Can less yield more? Is reducing nutrient input into the environment compatible with maintaining crop production?Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXhtVaksLvM&md5=7a4e7f1c989f576e0625a5a7cb1d7f5aCAS | 15564127PubMed |

Good AG, Johnson SJ, De Pauw M, Carroll RT, Savidov N (2007) Engineering nitrogen use efficiency with alanine aminotransferase. Canadian Journal of Botany-Revue Canadienne De Botanique 85, 252–262.

Grami B, Lacroix LJ (1977) Cultivar variation in total nitrogen uptake in rape. Canadian Journal of Plant Science 57, 619–624.
| Cultivar variation in total nitrogen uptake in rape.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaE2sXltlejurs%3D&md5=f5533ee73f156dee9f5a8c695d728a83CAS |

Habash DZ, Massiah AJ, Rong HL, Wallsgrove RM, Leigh RA (2001) The role of cytosolic glutamine synthetase in wheat. Annals of Applied Biology 138, 83–89.
| The role of cytosolic glutamine synthetase in wheat.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXkvVOmt7Y%3D&md5=293716cd0d0f7098b17beddca5be11d6CAS |

Habash D, Bernard S, Schondelmaier J, Weyen J, Quarrie S (2007) The genetics of nitrogen use in hexaploid wheat: N utilisation, development and yield. Theoretical and Applied Genetics 114, 403–419.
| The genetics of nitrogen use in hexaploid wheat: N utilisation, development and yield.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXosFKrtA%3D%3D&md5=7dc344526e5ba8d8c53237aaf9f5c29bCAS | 17180378PubMed |

Harrison J, Hirel B, Limami AM (2004) Variation in nitrate uptake and assimilation between two ecotypes of Lotus japonicus and their recombinant inbred lines. Physiologia Plantarum 120, 124–131.
| Variation in nitrate uptake and assimilation between two ecotypes of Lotus japonicus and their recombinant inbred lines.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXpvFSktA%3D%3D&md5=8fc2745b5d4135dd312dd83282dcca69CAS | 15032884PubMed |

Hayman P, Crean J, Mullen J, Parton K (2007) How do probabilistic seasonal climate forecasts compare with other innovations that Australian farmers are encouraged to adopt? Australian Journal of Agricultural Research 58, 975–984.
| How do probabilistic seasonal climate forecasts compare with other innovations that Australian farmers are encouraged to adopt?Crossref | GoogleScholarGoogle Scholar |

Heffner EL, Sorrells ME, Jannink JL (2009) Genomic selection for crop improvement. Crop Science 49, 1–12.
| Genomic selection for crop improvement.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXjsF2it78%3D&md5=6beb47aa1a6d920bf03ca0d655ecdbf0CAS |

Henriksen GH, Raj Raman D, Walker LP, Spanswick RM (1992) Measurement of net fluxes of ammonium and nitrate at the surface of barley roots using ion-sensitive microelectrodes. II. Patterns of uptake along the root axis and evaluation of the microelectrode flux estimation technique. Plant Physiology 99, 734–747.
| Measurement of net fluxes of ammonium and nitrate at the surface of barley roots using ion-sensitive microelectrodes. II. Patterns of uptake along the root axis and evaluation of the microelectrode flux estimation technique.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK38XltVyhtLk%3D&md5=d5a0511431990aa366933023b1b63c2bCAS | 16668947PubMed |

Hibberd JM, Sheehy JE, Langdale JA (2008) Using C4 photosynthesis to increase the yield of rice–rationale and feasibility. Current Opinion in Plant Biology 11, 228–231.
| Using C4 photosynthesis to increase the yield of rice–rationale and feasibility.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXktFCmsLs%3D&md5=d92ba9ad970f6152c3023fc1e272919aCAS | 18203653PubMed |

Hirel B, Bertin P, Quilleré I, Bourdoncle W, Attagnant C, Dellay C, Gouy A, Cadiou S, Retailliau C, Falque M, Gallais A (2001) Towards a better understanding of the genetic and physiological basis for nitrogen use efficiency in maize. Plant Physiology 125, 1258–1270.
| Towards a better understanding of the genetic and physiological basis for nitrogen use efficiency in maize.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXitFWrt7c%3D&md5=5a5389ffb594b891c3a6bb02d20c9867CAS | 11244107PubMed |

Hirel B, Le Gouis J, Ney B, Gallais A (2007) The challenge of improving nitrogen use efficiency in crop plants: towards a more central role for genetic variability and quantitative genetics within integrated approaches. Journal of Experimental Botany 58, 2369–2387.
| The challenge of improving nitrogen use efficiency in crop plants: towards a more central role for genetic variability and quantitative genetics within integrated approaches.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXos1ykt74%3D&md5=22c039d0b3b8a37715bed8500d17318bCAS | 17556767PubMed |

Hörtensteiner S, Feller U (2002) Nitrogen metabolism and remobilization during senescence. Journal of Experimental Botany 53, 927–937.
| Nitrogen metabolism and remobilization during senescence.Crossref | GoogleScholarGoogle Scholar | 11912235PubMed |

Hoshida H, Tanaka Y, Hibino T, Hayashi Y, Tanaka A, Takabe T (2000) Enhanced tolerance to salt stress in transgenic rice that overexpresses chloroplast glutamine synthetase. Plant Molecular Biology 43, 103–111.
| Enhanced tolerance to salt stress in transgenic rice that overexpresses chloroplast glutamine synthetase.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3cXlvVCjsL0%3D&md5=3f353c39355e416163f45ab44f4dc1d3CAS | 10949377PubMed |

Hsieh MH, Lam HM, van de Loo FJ, Coruzzi G (1998) A PII-like protein in Arabidopsis: putative role in nitrogen sensing. Proceedings of the National Academy of Sciences of the United States of America 95, 13965–13970.
| A PII-like protein in Arabidopsis: putative role in nitrogen sensing.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK1cXnsVGhurY%3D&md5=185f62416c03a7a3b4fe70907456a586CAS | 9811909PubMed |

Huang BE, George AW, Forrest KL, Kilian A, Hayden MJ, Morell MK, Cavanagh CR (2012) A multiparent advanced generation inter-cross population for genetic analysis in wheat. Plant Biotechnology Journal 10, 826–839.
| A multiparent advanced generation inter-cross population for genetic analysis in wheat.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38XhsVensL7J&md5=d4e0a732ed5f00a3223aca4fa155125bCAS | 22594629PubMed |

Hwang I, Goodman HM (1995) An Arabidopsis thaliana root-specific kinase homolog is induced by dehydration, ABA, and NaCl. The Plant Journal 8, 37–43.
| An Arabidopsis thaliana root-specific kinase homolog is induced by dehydration, ABA, and NaCl.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2MXnslSlt7s%3D&md5=02171ba665d3a40602ea4ec09e059065CAS | 7655506PubMed |

Imai K, Suzuki Y, Mae T, Makino A (2008) Changes in the synthesis of Rubisco in rice leaves in relation to senescence and N influx. Annals of Botany 101, 135–144.
| Changes in the synthesis of Rubisco in rice leaves in relation to senescence and N influx.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXitlans7c%3D&md5=16c8669c8b103c716b6c248c0f7a6c4bCAS | 17965028PubMed |

Iniguez AL, Dong YM, Triplett EW (2004) Nitrogen fixation in wheat provided by Klebsiella pneumoniae 342. Molecular Plant-Microbe Interactions 17, 1078–1085.
| Nitrogen fixation in wheat provided by Klebsiella pneumoniae 342.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXnvVarurg%3D&md5=1615e8e251aacba02f415113cdc94789CAS | 15497400PubMed |

Ishitani M, Xiong LM, Stevenson B, Zhu JK (1997) Genetic analysis of osmotic and cold stress signal transduction in Arabidopsis: interactions and convergence of abscisic acid-dependent and abscisic acid-independent pathways. The Plant Cell 9, 1935–1949.
| Genetic analysis of osmotic and cold stress signal transduction in Arabidopsis: interactions and convergence of abscisic acid-dependent and abscisic acid-independent pathways.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2sXnsl2mtrs%3D&md5=8a50108f8ee7e8a89755b4c0914f5e60CAS | 9401119PubMed |

Jackson WA, Volk RJ (1992) Nitrate and ammmonium uptake by maize: adaption during relief from nitrogen suppression. New Phytologist 122, 439–446.
| Nitrate and ammmonium uptake by maize: adaption during relief from nitrogen suppression.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK3sXht1Wjtr4%3D&md5=18d4318fa2a2bc00025821666b2f831aCAS |

Kamprath EJ, Moll RH, Rodriguez N (1982) Effects of nitrogen-fertilization and recurrent selection on performance of hybrid populations of corn. Agronomy Journal 74, 955–958.
| Effects of nitrogen-fertilization and recurrent selection on performance of hybrid populations of corn.Crossref | GoogleScholarGoogle Scholar |

Keeney DR (1982) Nitrogen management for maximum efficiency and minimum pollution. In ‘Nitrogen in agricultural soils’. pp. 605–649. (American Society of Agronomy: Madison, WI, USA)

Kichey T, Hirel B, Heumez E, Dubois F, Le Gouis J (2007) In winter wheat (Triticum aestivum L.), post-anthesis nitrogen uptake and remobilisation to the grain correlates with agronomic traits and nitrogen physiological markers. Field Crops Research 102, 22–32.
| In winter wheat (Triticum aestivum L.), post-anthesis nitrogen uptake and remobilisation to the grain correlates with agronomic traits and nitrogen physiological markers.Crossref | GoogleScholarGoogle Scholar |

Kim SA, Kwak JM, Jae SK, Wang MH, Nam HG (2001) Overexpression of the AtGluR2 gene encoding an Arabidopsis homolog of mammalian glutamate receptors impairs calcium utilization and sensitivity to ionic stress in transgenic plants. Plant & Cell Physiology 42, 74–84.
| Overexpression of the AtGluR2 gene encoding an Arabidopsis homolog of mammalian glutamate receptors impairs calcium utilization and sensitivity to ionic stress in transgenic plants.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXns1Cntw%3D%3D&md5=2ceec1c58b60f70c0060bdebb8591badCAS |

Kumar A, Kaiser BN, Siddiqi MY, Glass ADM (2006) Functional characterisation of OsAMT1.1 overexpression lines of rice, Oryza sativa. Functional Plant Biology 33, 339–346.
| Functional characterisation of OsAMT1.1 overexpression lines of rice, Oryza sativa.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XjtVOmu7g%3D&md5=8361f055daa22f8f75b0daf3d76e0aaaCAS |

Kurai T, Wakayama M, Abiko T, Yanagisawa S, Aoki N, Ohsugi R (2011) Introduction of the ZmDof1 gene into rice enhances carbon and nitrogen assimilation under low-nitrogen conditions. Plant Biotechnology Journal 9, 826–837.
| Introduction of the ZmDof1 gene into rice enhances carbon and nitrogen assimilation under low-nitrogen conditions.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXhtlemtrjM&md5=88a1f57f185f484c9208cf347c059437CAS | 21624033PubMed |

Ladha JK, Kirk GJD, Bennett J, Peng S, Reddy CK, Reddy PM, Singh U (1998) Opportunities for increased nitrogen-use efficiency from improved lowland rice germplasm. Field Crops Research 56, 41–71.
| Opportunities for increased nitrogen-use efficiency from improved lowland rice germplasm.Crossref | GoogleScholarGoogle Scholar |

Lam HM, Wong P, Chan HK, Yam KM, Chen L, Chow CM, Coruzzi GM (2003) Overexpression of the ASN1 gene enhances nitrogen status in seeds of Arabidopsis. Plant Physiology 132, 926–935.
| Overexpression of the ASN1 gene enhances nitrogen status in seeds of Arabidopsis.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXkslertLk%3D&md5=b1be7f90d184a011a9e51f93c510f0f1CAS | 12805621PubMed |

Laperche A, Devienne-Barret F, Maury O, Le Gouis J, Ney B (2006) A simplified conceptual model of carbon/nitrogen functioning for QTL analysis of winter wheat adaptation to nitrogen deficiency. Theoretical and Applied Genetics 113, 1131–1146.
| A simplified conceptual model of carbon/nitrogen functioning for QTL analysis of winter wheat adaptation to nitrogen deficiency.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XhtVSktbfP&md5=28cf2c2e6c1373177d67718c324296abCAS | 16909280PubMed |

Laperche A, Brancourt-Hulmel M, Heumez E, Gardet O, Hanocq E, Devienne-Barret F, Le Gouis J (2007) Using genotype × nitrogen interaction variables to evaluate the QTL involved in wheat tolerance to nitrogen constraints. Theoretical and Applied Genetics 115, 399–415.
| Using genotype × nitrogen interaction variables to evaluate the QTL involved in wheat tolerance to nitrogen constraints.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXnvFKqtrc%3D&md5=21d0a8cc9fd8b905a91ba2837e66e9d9CAS | 17569029PubMed |

Le Gouis J, Pluchard P (1996) Genetic variation for nitrogen use efficiency in winter wheat (Triticum aestivum L.). Euphytica 92, 221–224.
| Genetic variation for nitrogen use efficiency in winter wheat (Triticum aestivum L.).Crossref | GoogleScholarGoogle Scholar |

Le Gouis J, Beghin D, Heumez E, Pluchard P (2000) Genetic differences for nitrogen uptake and nitrogen utilisation efficiencies in winter wheat. European Journal of Agronomy 12, 163–173.
| Genetic differences for nitrogen uptake and nitrogen utilisation efficiencies in winter wheat.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3cXjvFKnt7s%3D&md5=0288fc450be315e28167ff8a120acc3cCAS |

Lemaire G, Salette J (1984) Relationship between growth and nitrogen uptake in a pure grass stand. 1. Environmental effects. Agronomie 4, 423–430.
| Relationship between growth and nitrogen uptake in a pure grass stand. 1. Environmental effects.Crossref | GoogleScholarGoogle Scholar |

Léran S, Varala K, Boyer JC, Chiurazzi M, Crawford N, Daniel-Vedele F, David L, Dickstein R, Fernandez E, Forde B, et al (2014) A unified nomenclature of NITRATE TRANSPORTER 1/PEPTIDE TRANSPORTER family members in plants. Trends in Plant Science 19, 5–9.
| A unified nomenclature of NITRATE TRANSPORTER 1/PEPTIDE TRANSPORTER family members in plants.Crossref | GoogleScholarGoogle Scholar | 24055139PubMed |

Li X, Guo C, Gu J, Duan W, Zhao M, Ma C, Du X, Lu W, Xiao K (2014) Overexpression of VP, a vacuolar H-pyrophosphatase gene in wheat (Triticum aestivum L.), improves tobacco plant growth under Pi and N deprivation, high salinity, and drought. Journal of Experimental Botany 65, 683–696.
| Overexpression of VP, a vacuolar H-pyrophosphatase gene in wheat (Triticum aestivum L.), improves tobacco plant growth under Pi and N deprivation, high salinity, and drought.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC2cXhs1Chs74%3D&md5=912e8b78d43384b1a7052f08e5693364CAS | 24474810PubMed |

Lian X, Xing Y, Yan H, Xu C, Li X, Zhang Q (2005) QTLs for low nitrogen tolerance at seedling stage identified using a recombinant inbred line population derived from an elite rice hybrid. Theoretical and Applied Genetics 112, 85–96.
| QTLs for low nitrogen tolerance at seedling stage identified using a recombinant inbred line population derived from an elite rice hybrid.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXht1Oisr7J&md5=53395572cb021cd93c0633bc39d4f8d6CAS | 16189659PubMed |

Liao MT, Fillery IRP, Palta JA (2004) Early vigorous growth is a major factor influencing nitrogen uptake in wheat. Functional Plant Biology 31, 121–129.
| Early vigorous growth is a major factor influencing nitrogen uptake in wheat.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXhsl2gtrk%3D&md5=d8ea1fdc343e44d9e8a13f1e0d85bfe0CAS |

Liao MT, Palta JA, Fillery IRP (2006) Root characteristics of vigorous wheat improve early nitrogen uptake. Australian Journal of Agricultural Research 57, 1097–1107.
| Root characteristics of vigorous wheat improve early nitrogen uptake.Crossref | GoogleScholarGoogle Scholar |

Lillo C (2008) Signalling cascades integrating light-enhanced nitrate metabolism. The Biochemical Journal 415, 11–19.
| Signalling cascades integrating light-enhanced nitrate metabolism.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXhtFSltLfN&md5=00ae3ae1bcd3aff9d92060a19703a875CAS | 18778247PubMed |

Lillo C, Lea US, Leydecker MT, Meyer C (2003) Mutation of the regulatory phosphorylation site of tobacco nitrate reductase results in constitutive activation of the enzyme in vivo and nitrite accumulation. The Plant Journal 35, 566–573.
| Mutation of the regulatory phosphorylation site of tobacco nitrate reductase results in constitutive activation of the enzyme in vivo and nitrite accumulation.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXotFCrsr8%3D&md5=c77067b3610db517383b039e6299a0d5CAS | 12940950PubMed |

Limami AM, Rouillon C, Glevarec G, Gallais A, Hirel B (2002) Genetic and physiological analysis of germination efficiency in maize in relation to nitrogen metabolism reveals the importance of cytosolic glutamine synthetase. Plant Physiology 130, 1860–1870.
| Genetic and physiological analysis of germination efficiency in maize in relation to nitrogen metabolism reveals the importance of cytosolic glutamine synthetase.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXktlGk&md5=2c01042e984b879e564bb01358270867CAS | 12481069PubMed |

Lin SH, Kuo HF, Canivenc G, Lin CS, Lepetit M, Hsu PK, Tillard P, Lin HL, Wang YY, Tsai CB, Gojon A, Tsay YF (2008) Mutation of the Arabidopsis NRT1.5 nitrate transporter causes defective root-to-shoot nitrate transport. The Plant Cell 20, 2514–2528.
| Mutation of the Arabidopsis NRT1.5 nitrate transporter causes defective root-to-shoot nitrate transport.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXhtlCnsLjE&md5=2e9a54d784a551fce04c6ba1381436ddCAS | 18780802PubMed |

Lin MT, Occhialini A, Andralojc PJ, Parry MAJ, Hanson MR (2014) A faster Rubisco with potential to increase photosynthesis in crops. Nature 513, 547–550.
| A faster Rubisco with potential to increase photosynthesis in crops.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC2cXhs1Wjs7nF&md5=3e6540b46be5ff859be70c8c8423f8feCAS | 25231869PubMed |

Liu ZB, Ulmasov T, Shi X, Hagen G, Guilfoyle TJ (1994) Soybean GH3 promoter contains multiple auxin-inducible elements. The Plant Cell 6, 645–657.
| Soybean GH3 promoter contains multiple auxin-inducible elements.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2cXmvFChtb0%3D&md5=0b1610b0c8935d8427152338bad43542CAS | 8038604PubMed |

Liu KH, Huang CY, Tsay YF (1999) CHL1 is a dual-affinity nitrate transporter of Arabidopsis involved in multiple phases of nitrate uptake. The Plant Cell 11, 865–874.
| CHL1 is a dual-affinity nitrate transporter of Arabidopsis involved in multiple phases of nitrate uptake.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK1MXjvVWqu7Y%3D&md5=e5ef8996e33c04daf2f2c658c624c782CAS | 10330471PubMed |

Liu J, Li J, Chen F, Zhang F, Ren T, Zhuang Z, Mi G (2008) Mapping QTLs for root traits under different nitrate levels at the seedling stage in maize (Zea mays L.). Plant and Soil 305, 253–265.
| Mapping QTLs for root traits under different nitrate levels at the seedling stage in maize (Zea mays L.).Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXjsVGitLY%3D&md5=f93cf683389b981fc8bcdab93c81de4bCAS |

Liu R, Zhang H, Zhao P, Zhang Z, Liang W, Tian Z, Zheng Y (2012) Mining of candidate maize genes for nitrogen use efficiency by integrating gene expression and QTL data. Plant Molecular Biology Reporter 30, 297–308.
| Mining of candidate maize genes for nitrogen use efficiency by integrating gene expression and QTL data.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38XktFKht7Y%3D&md5=531f04071ae27c0f5f23ffb35eafa46cCAS |

Loque D, von Wiren N (2004) Regulatory levels for the transport of ammonium in plant roots. Journal of Experimental Botany 55, 1293–1305.
| Regulatory levels for the transport of ammonium in plant roots.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXkvVSrtr4%3D&md5=15e801c6b3b4bfe12dc4edb58dbd97b2CAS | 15133056PubMed |

Loque D, Mora SI, Andrade SLA, Pantoja O, Frommer WB (2009) Pore mutations in ammonium transporter AMT1 with increased electrogenic ammonium transport activity. Journal of Biological Chemistry 284, 24988–24995.
| Pore mutations in ammonium transporter AMT1 with increased electrogenic ammonium transport activity.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXhtV2nsLbJ&md5=58008f3c7a50a4a8ed55e2bcc45da8e2CAS | 19581303PubMed |

Loudet O, Chaillou S, Krapp A, Daniel-Vedele F (2003a) Quantitative trait loci analysis of water and anion contents in interaction with nitrogen availability in Arabidopsis thaliana. Genetics 163, 711–722.

Loudet O, Chaillou S, Merigout P, Talbotec J, Daniel-Vedele F (2003b) Quantitative trait loci analysis of nitrogen use efficiency in Arabidopsis. Plant Physiology 131, 345–358.
| Quantitative trait loci analysis of nitrogen use efficiency in Arabidopsis.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXnvVGnuw%3D%3D&md5=36a3fd08aa84276d06b3871a2f3bef1aCAS | 12529542PubMed |

Ludewig U, Neuhduser B, Dynowski M (2007) Molecular mechanisms of ammonium transport and accumulation in plants. FEBS Letters 581, 2301–2308.
| Molecular mechanisms of ammonium transport and accumulation in plants.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXls1ahsr4%3D&md5=52aba427b9b1e5b76c5fd05654a2bc29CAS | 17397837PubMed |

Lynch JP (2007) Roots of the second Green Revolution. Australian Journal of Botany 55, 493–512.
| Roots of the second Green Revolution.Crossref | GoogleScholarGoogle Scholar |

Mae T, Inaba A, Kaneta Y, Masaki S, Sasaki M, Aizawa M, Okawa S, Hasegawa S, Makino A (2006) A large-grain rice cultivar, Akita 63, exhibits high yields with high physiological N-use efficiency. Field Crops Research 97, 227–237.
| A large-grain rice cultivar, Akita 63, exhibits high yields with high physiological N-use efficiency.Crossref | GoogleScholarGoogle Scholar |

Malagoli P, Laine P, Rossato L, Ourry A (2005) Dynamics of nitrogen uptake and mobilization in field-grown winter oilseed rape (Brassica napus) from stem extension to harvest. II. An N-15-labelling-based simulation model of N partitioning between vegetative and reproductive tissues. Annals of Botany 95, 1187–1198.
| Dynamics of nitrogen uptake and mobilization in field-grown winter oilseed rape (Brassica napus) from stem extension to harvest. II. An N-15-labelling-based simulation model of N partitioning between vegetative and reproductive tissues.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXlvVSltL8%3D&md5=5ae09ebe66965243671af2cbc7a71ebcCAS | 15802311PubMed |

Man H-M, Boriel R, El-Khatib R, Kirby EG (2005) Characterization of transgenic poplar with ectopic expression of pine cytosolic glutamine synthetase under conditions of varying nitrogen availability. New Phytologist 167, 31–39.
| Characterization of transgenic poplar with ectopic expression of pine cytosolic glutamine synthetase under conditions of varying nitrogen availability.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXmtl2nsb0%3D&md5=ca22571c362688ecb943be566c74f4c9CAS | 15948827PubMed |

Marschner H (1995) ‘Mineral nutrition of higher plants.’ (2nd edn) (Academic Press: London)

Martin A, Lee J, Kichey T, Gerentes D, Zivy M, Tatout C, Dubois F, Balliau T, Valot B, Davanture M, et al (2006) Two cytosolic glutamine synthetase isoforms of maize are specifically involved in the control of grain production. The Plant Cell 18, 3252–3274.
| Two cytosolic glutamine synthetase isoforms of maize are specifically involved in the control of grain production.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXit1Crtg%3D%3D&md5=07fccc9c74d760e72e783393b0219106CAS | 17138698PubMed |

Martre P, Porter JR, Jamieson PD, Triboï E (2003) Modeling grain nitrogen accumulation and protein composition to understand the sink/source regulations of nitrogen remobilization for wheat. Plant Physiology 133, 1959–1967.
| Modeling grain nitrogen accumulation and protein composition to understand the sink/source regulations of nitrogen remobilization for wheat.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXhvFKm&md5=54f2fc70967983c92833f3fbd8da7a5cCAS | 14630962PubMed |

Masclaux-Daubresse Cl, Chardon F (2011) Exploring nitrogen remobilization for seed filling using natural variation in Arabidopsis thaliana. Journal of Experimental Botany 62, 2131–2142.
| Exploring nitrogen remobilization for seed filling using natural variation in Arabidopsis thaliana.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXjsFyjtbo%3D&md5=a1167ff5cb371a58ce4b1c614036ae1fCAS |

McAllister CH, Beatty PH, Good AG (2012) Engineering nitrogen use efficient crop plants: the current status. Plant Biotechnology Journal 10, 1011–1025.
| Engineering nitrogen use efficient crop plants: the current status.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3sXkvVWrtQ%3D%3D&md5=464fb6ebbea2e9dcba48572d6e80a5ffCAS | 22607381PubMed |

McMullen MD, Kresovich S, Villeda HS, Bradbury P, Li H, Sun Q, Flint-Garcia S, Thornsberry J, Acharya C, Bottoms C, et al (2009) Genetic properties of the maize nested association mapping population. Science 325, 737–740.
| Genetic properties of the maize nested association mapping population.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXptl2gurk%3D&md5=9def3b60c787c71f91e2fd61a9e8b3d6CAS | 19661427PubMed |

Mickelson S, See D, Meyer FD, Garner JP, Foster CR, Blake TK, Fischer AM (2003) Mapping of QTL associated with nitrogen storage and remobilization in barley (Hordeum vulgare L.) leaves. Journal of Experimental Botany 54, 801–812.
| Mapping of QTL associated with nitrogen storage and remobilization in barley (Hordeum vulgare L.) leaves.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXit1aru7k%3D&md5=13ed306d39bf2c8a3b8d1c564c70e577CAS | 12554723PubMed |

Migge A, Carrayol E, Hirel B, Becker TW (2000) Leaf-specific overexpression of plastidic glutamine synthetase stimulates the growth of transgenic tobacco seedlings. Planta 210, 252–260.
| Leaf-specific overexpression of plastidic glutamine synthetase stimulates the growth of transgenic tobacco seedlings.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3cXisVajug%3D%3D&md5=0518c8a2126c0d883c4d1153c8d74433CAS | 10664131PubMed |

Miller AJ, Smith SJ (1996) Nitrate transport and compartmentation in cereal root cells. Journal of Experimental Botany 47, 843–854.
| Nitrate transport and compartmentation in cereal root cells.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK28XkslSqtb4%3D&md5=44a95b6b0993708dd397786ccb77724eCAS |

Miller AJ, Fan XR, Orsel M, Smith SJ, Wells DM (2007) Nitrate transport and signalling. Journal of Experimental Botany 58, 2297–2306.
| Nitrate transport and signalling.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXos1ykt7s%3D&md5=9508916e83aa387bb652d1263637d681CAS | 17519352PubMed |

Miller AJ, Fan XR, Shen QR, Smith SJ (2008) Amino acids and nitrate as signals for the regulation of nitrogen acquisition. Journal of Experimental Botany 59, 111–119.
| Amino acids and nitrate as signals for the regulation of nitrogen acquisition.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXht1Sitbc%3D&md5=19dea0b59b26c323805139575873e681CAS | 18093964PubMed |

Miyao M, Masumoto C, Miyazawa S-I, Fukayama H (2011) Lessons from engineering a single-cell C4 photosynthetic pathway into rice. Journal of Experimental Botany 62, 3021–3029.
| Lessons from engineering a single-cell C4 photosynthetic pathway into rice.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXnsFWjtrc%3D&md5=437baeadada9a4ce4e2aaf2d253e4689CAS | 21459764PubMed |

Moll RH, Kamprath EJ, Jackson WA (1982) Analysis and interpretation of factors which contribute to efficiency of nitrogen-utilization. Agronomy Journal 74, 562–564.
| Analysis and interpretation of factors which contribute to efficiency of nitrogen-utilization.Crossref | GoogleScholarGoogle Scholar |

Moller IS, Gilliham M, Jha D, Mayo GM, Roy SJ, Coates JC, Haseloff J, Tester M (2009) Shoot Na(+) exclusion and increased salinity tolerance engineered by cell type-specific alteration of Na(+) transport in Arabidopsis. The Plant Cell 21, 2163–2178.
| Shoot Na(+) exclusion and increased salinity tolerance engineered by cell type-specific alteration of Na(+) transport in Arabidopsis.Crossref | GoogleScholarGoogle Scholar | 19584143PubMed |

Monaghan JM, Snape JW, Chojecki AJS, Kettlewell PS (2001) The use of grain protein deviation for identifying wheat cultivars with high grain protein concentration and yield. Euphytica 122, 309–317.
| The use of grain protein deviation for identifying wheat cultivars with high grain protein concentration and yield.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD38XltlWmuw%3D%3D&md5=f1841a5fed3102c128f10947fc3f7f5cCAS |

Moose S, Below FE (2009) Biotechnology approaches to improving maize nitrogen use efficiency. In ‘Biotechnology in agriculture and forestry. Vol. 63’. (Ed. ALLBA Kriz) pp. 65–77. (Springer: Berlin)

Moreau D, Burstin J, Aubert G, Huguet T, Ben C, Prosperi JM, Salon C, Munier-Jolain N (2012) Using a physiological framework for improving the detection of quantitative trait loci related to nitrogen nutrition in Medicago truncatula. Theoretical and Applied Genetics 124, 755–768.
| Using a physiological framework for improving the detection of quantitative trait loci related to nitrogen nutrition in Medicago truncatula.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38XitlKgsb4%3D&md5=5769cbe0a353c6353855b2aa7d2837e4CAS | 22113590PubMed |

Morgan MA, Jackson WA (1988) Suppression of ammonium uptake by nitrogen supply and its relief during nitrogen limitation. Physiologia Plantarum 73, 38–45.
| Suppression of ammonium uptake by nitrogen supply and its relief during nitrogen limitation.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL1cXktlOhsL4%3D&md5=a4809cfe93fdf97a0782bc934673108eCAS |

Muthukumarasamy R, Govindarajan M, Vadivelu M, Revathi G (2006) N-fertilizer saving by the inoculation of Gluconacetobacter diazotrophicus and Herbaspirillum sp. in micropropagated sugarcane plants. Microbiological Research 161, 238–245.
| N-fertilizer saving by the inoculation of Gluconacetobacter diazotrophicus and Herbaspirillum sp. in micropropagated sugarcane plants.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28Xot1amtbc%3D&md5=ff811a3148fe4476511b1747ce7ebbebCAS | 16765840PubMed |

Oaks A (1994) Primary nitrogen assimilation in higher plants and its regulation. Canadian Journal of Botany 72, 739–750.
| Primary nitrogen assimilation in higher plants and its regulation.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2cXmvFOisro%3D&md5=42e26110a84e5de0b96ef49c181f3406CAS |

Obara M, Kajiura M, Fukuta Y, Yano M, Hayashi M, Yamaya T, Sato T (2001) Mapping of QTLs associated with cytosolic glutamine synthetase and NADH‐glutamate synthase in rice (Oryza sativa L.). Journal of Experimental Botany 52, 1209–1217.
| Mapping of QTLs associated with cytosolic glutamine synthetase and NADH‐glutamate synthase in rice (Oryza sativa L.).Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXlsVCmsrc%3D&md5=01e1664fde002d1c5d0826a0e1983f1eCAS | 11432939PubMed |

Obara M, Tamura W, Ebitani T, Yano M, Sato T, Yamaya T (2010) Fine-mapping of qRL6.1, a major QTL for root length of rice seedlings grown under a wide range of NH4+ concentrations in hydroponic conditions. Theoretical and Applied Genetics 121, 535–547.
| Fine-mapping of qRL6.1, a major QTL for root length of rice seedlings grown under a wide range of NH4+ concentrations in hydroponic conditions.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXoslyqsbo%3D&md5=441ed1ad9c3db6ddd74a2e853bb64f49CAS | 20390245PubMed |

Obara M, Takeda T, Hayakawa T, Yamaya T (2011) Mapping quantitative trait loci controlling root length in rice seedlings grown with low or sufficient supply using backcross recombinant lines derived from a cross between Oryza sativa L. and Oryza glaberrima Steud. Soil Science and Plant Nutrition 57, 80–92.
| Mapping quantitative trait loci controlling root length in rice seedlings grown with low or sufficient supply using backcross recombinant lines derived from a cross between Oryza sativa L. and Oryza glaberrima Steud.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXhtVKlsLfO&md5=3a0d66b251f2b5854a1904cfeaf36766CAS |

Okamoto M, Kumar A, Li WB, Wang Y, Siddiqi MY, Crawford NM, Glass ADM (2006) High-affinity nitrate transport in roots of Arabidopsis depends on expression of the NAR2-like gene AtNRT3.1. Plant Physiology 140, 1036–1046.
| High-affinity nitrate transport in roots of Arabidopsis depends on expression of the NAR2-like gene AtNRT3.1.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28Xislygs74%3D&md5=466e30b5bde6e8f89b9fff42a143a0e5CAS | 16415212PubMed |

Oliveira IC, Brears T, Knight TJ, Clark A, Coruzzi GM (2002) Overexpression of cytosolic glutamine synthetase. Relation to nitrogen, light, and photorespiration. Plant Physiology 129, 1170–1180.
| Overexpression of cytosolic glutamine synthetase. Relation to nitrogen, light, and photorespiration.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD38XlsFajsLg%3D&md5=e24262c64bcca2c02d1525ee542b7ddeCAS | 12114571PubMed |

Ortiz-Monasterio JI, Sayre KD, Rajaram S, McMahon M (1997) Genetic progress in wheat yield and nitrogen use efficiency under four nitrogen rates. Crop Science 37, 898–904.
| Genetic progress in wheat yield and nitrogen use efficiency under four nitrogen rates.Crossref | GoogleScholarGoogle Scholar |

Oury FX, Godin C (2007) Yield and grain protein concentration in bread wheat: how to use the negative relationship between the two characters to identify favourable genotypes? Euphytica 157, 45–57.
| Yield and grain protein concentration in bread wheat: how to use the negative relationship between the two characters to identify favourable genotypes?Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXpslaqtbc%3D&md5=b22a39529cd4b5c72ac424aeffdf4959CAS |

Palta JA, Kobata T, Turner NC, Fillery IR (1994) Remobilization of carbon and nitrogen in wheat as influenced by postanthesis water deficits. Crop Science 34, 118–124.
| Remobilization of carbon and nitrogen in wheat as influenced by postanthesis water deficits.Crossref | GoogleScholarGoogle Scholar |

Pate JS (1973) Uptake, assimilation and transport of nitrogen compounds by plants. Soil Biology & Biochemistry 5, 109–119.
| Uptake, assimilation and transport of nitrogen compounds by plants.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaE3sXlsFaqsg%3D%3D&md5=4897d44ccabc8dcc7a40b1f11efd4bb1CAS |

Peoples MB, Mosier AR, Freney JR (1995) Minimizing gaseous losses of nitrogen. In ‘Nitrogen fertilization in the environment’. (Ed. PE Bacon) pp. 505–602. (Marcel Dekker: New York)

Plesch G, Kamann E, Mueller-Roeber B (2000) Cloning of regulatory sequences mediating guard-cell-specific gene expression. Gene 249, 83–89.
| Cloning of regulatory sequences mediating guard-cell-specific gene expression.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3cXjsVeltL4%3D&md5=dd6bfa951a1236677b996aef116883d8CAS | 10831841PubMed |

Plesch G, Ehrhardt T, Mueller-Roeber B (2001) Involvement of TAAAG elements suggests a role for Dof transcription factors in guard cell-specific gene expression. The Plant Journal 28, 455–464.
| Involvement of TAAAG elements suggests a role for Dof transcription factors in guard cell-specific gene expression.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD38XmtVGhug%3D%3D&md5=b8288ffc48f1fbf8b30a128749fce2b8CAS | 11737782PubMed |

Plett D, Safwat G, Gilliham M, Moller IS, Roy S, Shirley N, Jacobs A, Johnson A, Tester M (2010a) Improved salinity tolerance of rice through cell type-specific expression of AtHKT1;1. PLoS One 5, e12571
| Improved salinity tolerance of rice through cell type-specific expression of AtHKT1;1.Crossref | GoogleScholarGoogle Scholar | 20838445PubMed |

Plett D, Toubia J, Garnett T, Tester M, Kaiser BN, Baumann U (2010b) Dichotomy in the NRT gene families of dicots and grass species. PLoS One 5, e15289
| Dichotomy in the NRT gene families of dicots and grass species.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXhsFKlur%2FP&md5=d9d891e0269a0cf9554c83695642905aCAS | 21151904PubMed |

Poland J, Endelman J, Dawson J, Rutkoski J, Wu S, Manes Y, Dreisigacker S, Crossa J, Sánchez-Villeda H, Sorrells M, Jannink J-L (2012) Genomic selection in wheat breeding using genotyping-by-sequencing. The Plant Genome 5, 103–113.
| Genomic selection in wheat breeding using genotyping-by-sequencing.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3sXlvVaksrw%3D&md5=4e58582882eac99ee2b3c0246292a7caCAS |

Quraishi UM, Abrouk M, Murat F, Pont C, Foucrier S, Desmaizieres G, Confolent C, Rivière N, Charmet G, Paux E, Murigneux A, Guerreiro L, Lafarge S, Le Gouis J, Feuillet C, Salse J (2011) Cross-genome map based dissection of a nitrogen use efficiency ortho-metaQTL in bread wheat unravels concerted cereal genome evolution. The Plant Journal 65, 745–756.
| Cross-genome map based dissection of a nitrogen use efficiency ortho-metaQTL in bread wheat unravels concerted cereal genome evolution.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXjsFCjurc%3D&md5=1cd4f09e9043571fd98096aaf1304f78CAS | 21251102PubMed |

Rafalski JA (2010) Association genetics in crop improvement. Current Opinion in Plant Biology 13, 174–180.
| Association genetics in crop improvement.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXlsFahs78%3D&md5=eb60703511bb35402c39177fa54e5850CAS | 20089441PubMed |

Ranathunge K, El-kereamy A, Gidda S, Bi Y-M, Rothstein SJ (2014) AMT1;1 transgenic rice plants with enhanced NH4 + permeability show superior growth and higher yield under optimal and suboptimal NH4 + conditions. Journal of Experimental Botany 65, 965–979.
| AMT1;1 transgenic rice plants with enhanced NH4 + permeability show superior growth and higher yield under optimal and suboptimal NH4 + conditions.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC2cXjsVSgtb8%3D&md5=13ac34f6e8371e712313220d9e9294a1CAS | 24420570PubMed |

Rauh B, Basten C, Buckler E (2002) Quantitative trait loci analysis of growth response to varying nitrogen sources in Arabidopsis thaliana. Theoretical and Applied Genetics 104, 743–750.
| Quantitative trait loci analysis of growth response to varying nitrogen sources in Arabidopsis thaliana.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD38XktlWntr0%3D&md5=2b218a2d4fd8022cfa587fb959760123CAS |

Raun WR, Johnson GV (1999) Improving nitrogen use efficiency for cereal production. Agronomy Journal 91, 357–363.
| Improving nitrogen use efficiency for cereal production.Crossref | GoogleScholarGoogle Scholar |

Raven JA, Smith FA (1976) Nitrogen assimilation and transport in vascular land plants in relation to intracellular pH regulation. New Phytologist 76, 415–431.
| Nitrogen assimilation and transport in vascular land plants in relation to intracellular pH regulation.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaE28XktFOjt7o%3D&md5=3b9caab73e97c678d52f40b944aa69e9CAS |

Rebetzke GJ, Richards RA (1999) Genetic improvement of early vigour in wheat. Australian Journal of Agricultural Research 50, 291–301.
| Genetic improvement of early vigour in wheat.Crossref | GoogleScholarGoogle Scholar |

Remans T, Nacry P, Pervent M, Filleur S, Diatloff E, Mounier E, Tillard P, Forde BG, Gojon A (2006) The Arabidopsis NRT1.1 transporter participates in the signaling pathway triggering root colonization of nitrate-rich patches. Proceedings of the National Academy of Sciences of the United States of America 103, 19206–19211.
| The Arabidopsis NRT1.1 transporter participates in the signaling pathway triggering root colonization of nitrate-rich patches.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XhtlChsrjO&md5=ff8207c95dc6f45c15a3274ffb4cbc83CAS | 17148611PubMed |

Ribaut J-M, Fracheboud Y, Monneveux P, Banziger M, Vargas M, Jiang C (2007) Quantitative trait loci for yield and correlated traits under high and low soil nitrogen conditions in tropical maize. Molecular Breeding 20, 15–29.
| Quantitative trait loci for yield and correlated traits under high and low soil nitrogen conditions in tropical maize.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXks1ynsLk%3D&md5=bcda35080ba4fc21d5e4c01dd9a1d415CAS |

Rice EA, Khandelwal A, Creelman RA, Griffith C, Ahrens JE, Taylor JP, Murphy LR, Manjunath S, Thompson RL, Lingard MJ, et al (2014) Expression of a truncated ATHB17 protein in maize increases ear weight at silking. PLoS One 9, e94238
| Expression of a truncated ATHB17 protein in maize increases ear weight at silking.Crossref | GoogleScholarGoogle Scholar | 24736658PubMed |

Riggs PJ, Chelius MK, Iniguez AL, Kaeppler SM, Triplett EW (2001) Enhanced maize productivity by inoculation with diazotrophic bacteria. Australian Journal of Plant Physiology 28, 829–836.

Robinson D, Rorison IH (1983) Relationships between root morphology and nitrogen availability in a recent theoretical model describing nitrogen uptake from soil. Plant, Cell & Environment 6, 641–647.

Rockström J, Steffen W, Noone K, Persson A, Chapin FS, Lambin EF, Lenton TM, Scheffer M, Folke C, Schellnhuber HJ, et al (2009) A safe operating space for humanity. Nature 461, 472–475.
| A safe operating space for humanity.Crossref | GoogleScholarGoogle Scholar | 19779433PubMed |

Saal B, von Korff M, Léon J, Pillen K (2011) Advanced-backcross QTL analysis in spring barley: IV. Localization of QTL × nitrogen interaction effects for yield-related traits. Euphytica 177, 223–239.
| Advanced-backcross QTL analysis in spring barley: IV. Localization of QTL × nitrogen interaction effects for yield-related traits.Crossref | GoogleScholarGoogle Scholar |

Samonte SOP, Wilson LT, Medley JC, Pinson SRM, McClung AM, Lales JS (2006) Nitrogen utilization efficiency. Agronomy Journal 98, 168–176.
| Nitrogen utilization efficiency.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XhvVClurk%3D&md5=3d53d1a1721e2daa9ae403049ca8a3adCAS |

Sannemann W, Huang BE, Mathew B, Leon J (2015) Multi-parent advanced generation inter-cross in barley: high-resolution quantitative trait locus mapping for flowering time as a proof of concept. Molecular Breeding 35, Article:86
| Multi-parent advanced generation inter-cross in barley: high-resolution quantitative trait locus mapping for flowering time as a proof of concept.Crossref | GoogleScholarGoogle Scholar |

Schjoerring JK, Husted S, Mack G, Mattsson M (2002) The regulation of ammonium translocation in plants. Journal of Experimental Botany 53, 883–890.
| The regulation of ammonium translocation in plants.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD38XivFSntbw%3D&md5=5ceed633c5ee941c1832532778073afaCAS | 11912231PubMed |

Senthilvel S, Vinod KK, Malarvizhi P, Maheswaran M (2008) QTL and QTL × environment effects on agronomic and nitrogen acquisition traits in rice. Journal of Integrative Plant Biology 50, 1108–1117.
| QTL and QTL × environment effects on agronomic and nitrogen acquisition traits in rice.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXhtFKlt7nP&md5=3c8c9bce32eb3253acd40c5f4129a9c6CAS | 18844779PubMed |

Sentoku N, Taniguchi M, Sugiyama T, Ishimaru K, Ohsugi R, Takaiwa F, Toki S (2000) Analysis of the transgenic tobacco plants expressing Panicum miliaceum aspartate aminotransferase genes. Plant Cell Reports 19, 598–603.
| Analysis of the transgenic tobacco plants expressing Panicum miliaceum aspartate aminotransferase genes.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3cXltV2ltLc%3D&md5=1234ddc550f3e27271b6c7e26e7d7ff9CAS |

Shrawat AK, Carroll RT, DePauw M, Taylor GJ, Good AG (2008) Genetic engineering of improved nitrogen use efficiency in rice by the tissue-specific expression of alanine aminotransferase. Plant Biotechnology Journal 6, 722–732.
| Genetic engineering of improved nitrogen use efficiency in rice by the tissue-specific expression of alanine aminotransferase.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXhtFGhtLfP&md5=69b41d82d166e80c55d2189f132c1c5fCAS | 18510577PubMed |

Simmonds NW (1979) ‘Principles of crop improvement.’ (Longman: New York)

Sinclair TR (1998) Historical changes in harvest index and crop nitrogen accumulation. Crop Science 38, 638–643.
| Historical changes in harvest index and crop nitrogen accumulation.Crossref | GoogleScholarGoogle Scholar |

Smirnoff N, Stewart GR (1985) Nitrate assimilation and translocation by higher plants: comparative physiology and ecological consequences. Physiologia Plantarum 64, 133–140.
| Nitrate assimilation and translocation by higher plants: comparative physiology and ecological consequences.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL2MXks1yhs7g%3D&md5=a690db0f0c6e038e88d4b0ee99f35fd5CAS |

Steenbjerg F, Jakobsen ST (1963) Plant nutrition and yield curves. Soil Science 95, 69–88.
| Plant nutrition and yield curves.Crossref | GoogleScholarGoogle Scholar |

Suenaga A, Moriya K, Sonoda Y, Ikeda A, von Wiren N, Hayakawa T, Yamaguchi J, Yamaya T (2003) Constitutive expression of a novel-type ammonium transporter OsAMT2 in rice plants. Plant & Cell Physiology 44, 206–211.
| Constitutive expression of a novel-type ammonium transporter OsAMT2 in rice plants.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXhsFWmsLs%3D&md5=9f8226c8475e8a37371a1f760c746d30CAS |

Sutton MA, Howard CM, Erisman JW, Billen G, Bleeker A, Grennfelt P, van Grinsven H, Grizzetti B (Eds) (2011) ‘The European nitrogen assessment.’ (Cambridge University Press: Cambridge, UK)

Svečnjak Z, Rengel Z (2006a) Canola cultivars differ in nitrogen utilization efficiency at vegetative stage. Field Crops Research 97, 221–226.
| Canola cultivars differ in nitrogen utilization efficiency at vegetative stage.Crossref | GoogleScholarGoogle Scholar |

Svečnjak Z, Rengel Z (2006b) Nitrogen utilization efficiency in canola cultivars at grain harvest. Plant and Soil 283, 299–307.
| Nitrogen utilization efficiency in canola cultivars at grain harvest.Crossref | GoogleScholarGoogle Scholar |

Sylvester-Bradley R, Kindred DR (2009) Analysing nitrogen responses of cereals to prioritize routes to the improvement of nitrogen use efficiency. Journal of Experimental Botany 60, 1939–1951.
| Analysing nitrogen responses of cereals to prioritize routes to the improvement of nitrogen use efficiency.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXmtFSjtb0%3D&md5=fe27aa8c1105b95006cb2195a4d75f7dCAS | 19395389PubMed |

Takahashi M, Sasaki Y, Ida S, Morikawa H (2001) Nitrite reductase gene enrichment improves assimilation of NO2 in Arabidopsis. Plant Physiology 126, 731–741.
| Nitrite reductase gene enrichment improves assimilation of NO2 in Arabidopsis.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXks1Gms7w%3D&md5=0b266f7b8102034b97ca77440fb069dcCAS | 11402201PubMed |

Taniguchi Y, Ohkawa H, Masumoto C, Fukuda T, Tamai T, Lee K, Sudoh S, Tsuchida H, Sasaki H, Fukayama H, Miyao M (2008) Overproduction of C4 photosynthetic enzymes in transgenic rice plants: an approach to introduce the C4-like photosynthetic pathway into rice. Journal of Experimental Botany 59, 1799–1809.
| Overproduction of C4 photosynthetic enzymes in transgenic rice plants: an approach to introduce the C4-like photosynthetic pathway into rice.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXmtlelt78%3D&md5=958e0440d4e8ec208a846797c89cf88cCAS | 18316317PubMed |

Terce-Laforgue T, Bedu M, Dargel-Grafin C, Dubois F, Gibon Y, Restivo FM, Hirel B (2013) Resolving the role of plant glutamate dehydrogenase: II. Physiological characterization of plants overexpressing the two enzyme subunits individually or simultaneously. Plant & Cell Physiology 54, 1635–1647.
| Resolving the role of plant glutamate dehydrogenase: II. Physiological characterization of plants overexpressing the two enzyme subunits individually or simultaneously.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3sXhs1Smur7O&md5=6878eea12a6f6987aee084fa4a262628CAS |

Thomas H, Smart CM (1993) Crops that stay green. Annals of Applied Biology 123, 193–219.
| Crops that stay green.Crossref | GoogleScholarGoogle Scholar |

Thomsen HC, Eriksson D, Møller IS, Schjoerring JK (2014) Cytosolic glutamine synthetase: a target for improvement of crop nitrogen use efficiency? Trends in Plant Science 19, 656–663.
| Cytosolic glutamine synthetase: a target for improvement of crop nitrogen use efficiency?Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC2cXhtFChsrbF&md5=c2546ecf646c77a0e144bd1be649c8a5CAS | 25017701PubMed |

Tirol-Padre A, Ladha JK, Singh U, Laureles E, Punzalan G, Akita S (1996) Grain yield performance of rice genotypes at suboptimal levels of soil N as affected by N uptake and utilization efficiency. Field Crops Research 46, 127–143.
| Grain yield performance of rice genotypes at suboptimal levels of soil N as affected by N uptake and utilization efficiency.Crossref | GoogleScholarGoogle Scholar |

Tollenaar M, Wu J (1999) Yield improvement in temperate maize is attributable to greater stress tolerance. Crop Science 39, 1597–1604.
| Yield improvement in temperate maize is attributable to greater stress tolerance.Crossref | GoogleScholarGoogle Scholar |

Tong H-h, Chen L, Li W-p, Mei H-w, Xing Y-z, Yu X-q, Xu X-y, Zhang S-q, Luo L-j (2011) Identification and characterization of quantitative trait loci for grain yield and its components under different nitrogen fertilization levels in rice (Oryza sativa L.). Molecular Breeding 28, 495–509.
| Identification and characterization of quantitative trait loci for grain yield and its components under different nitrogen fertilization levels in rice (Oryza sativa L.).Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXhsFSjur3E&md5=2a81f7c214a8403fa21409bae2274513CAS |

Tsay Y-F, Chiu C-C, Tsai C-B, Ho C-H, Hsu P-K (2007) Nitrate transporters and peptide transporters. FEBS Letters 581, 2290–2300.
| Nitrate transporters and peptide transporters.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXls1aiu7Y%3D&md5=14100c0e1cb6dca6edd3bbddcd50325bCAS | 17481610PubMed |

Uauy C, Distelfeld A, Fahima T, Blechl A, Dubcovsky J (2006) A NAC gene regulating senescence improves grain protein, zinc, and iron content in wheat. Science 314, 1298–1301.
| A NAC gene regulating senescence improves grain protein, zinc, and iron content in wheat.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28Xht1agt7jL&md5=8d14ef440c5dbafd05ea6edb30572ff3CAS | 17124321PubMed |

van Herwaarden AF, Angus JF, Richards RA, Farquhar GD (1998a) ‘Haying-off’, the negative grain yield response of dryland wheat to nitrogen fertiliser – II. Carbohydrate and protein dynamics. Australian Journal of Agricultural Research 49, 1083–1093.
| ‘Haying-off’, the negative grain yield response of dryland wheat to nitrogen fertiliser – II. Carbohydrate and protein dynamics.Crossref | GoogleScholarGoogle Scholar |

van Herwaarden AF, Farquhar GD, Angus JF, Richards RA, Howe GN (1998b) ‘Haying-off’, the negative grain yield response of dryland wheat to nitrogen fertiliser – I. Biomass, grain yield, and water use. Australian Journal of Agricultural Research 49, 1067–1081.
| ‘Haying-off’, the negative grain yield response of dryland wheat to nitrogen fertiliser – I. Biomass, grain yield, and water use.Crossref | GoogleScholarGoogle Scholar |

van Herwaarden AF, Richards RA, Farquhar GD, Angus JF (1998c) ‘Haying-off’, the negative grain yield response of dryland wheat to nitrogen fertiliser – III. The influence of water deficit and heat shock. Australian Journal of Agricultural Research 49, 1095–1110.
| ‘Haying-off’, the negative grain yield response of dryland wheat to nitrogen fertiliser – III. The influence of water deficit and heat shock.Crossref | GoogleScholarGoogle Scholar |

Van Sanford DA, Mackown CT (1987a) Cultivar differences in nitrogen remobilization during grain fill in soft red winter-wheat. Crop Science 27, 295–300.
| Cultivar differences in nitrogen remobilization during grain fill in soft red winter-wheat.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL2sXksFOru78%3D&md5=2440b40fc3dd01972005f96256aef0f8CAS |

Van Sanford DA, MacKown CT (1987b) Cultivar differences in nitrogen remobilization during grain fill in soft red winter wheat. Crop Science 27, 295–300.
| Cultivar differences in nitrogen remobilization during grain fill in soft red winter wheat.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL2sXksFOru78%3D&md5=2440b40fc3dd01972005f96256aef0f8CAS |

Vincent R, Fraisier V, Chaillou S, Limami MA, Deleens E, Phillipson B, Douat C, Boutin JP, Hirel B (1997) Overexpression of a soybean gene encoding cytosolic glutamine synthetase in shoots of transgenic Lotus corniculatus L. plants triggers changes in ammonium assimilation and plant development. Planta 201, 424–433.
| Overexpression of a soybean gene encoding cytosolic glutamine synthetase in shoots of transgenic Lotus corniculatus L. plants triggers changes in ammonium assimilation and plant development.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2sXjtVeiu7c%3D&md5=ef02b5d4a6869ee2e5aedc3978ea3d60CAS | 9151446PubMed |

Waltz E (2011) Cisgenic crop exemption. Nature Biotechnology 29, 677
| Cisgenic crop exemption.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXpvVOktb8%3D&md5=ea8d2a38b8f6800832da7a8582e84358CAS |

Wang Y, Fu B, Pan L, Chen L, Fu X, Li K (2013) Overexpression of Arabidopsis Dof1, GS1 and GS2 enhanced nitrogen assimilation in transgenic tobacco grown under low-nitrogen conditions. Plant Molecular Biology Reporter 31, 886–900.
| Overexpression of Arabidopsis Dof1, GS1 and GS2 enhanced nitrogen assimilation in transgenic tobacco grown under low-nitrogen conditions.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3sXhtFajtL3F&md5=985f8c16050f76ff0a68ff273102ba3dCAS |

Ward ER, Ryals JA, Miflin BJ (1993) Chemical regulation of transgene expression in plants. Plant Molecular Biology 22, 361–366.
| Chemical regulation of transgene expression in plants.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK3sXltFegsrs%3D&md5=f1577e54f60c4594064f249cfc1852c2CAS | 8507836PubMed |

Wei D, Cui K, Ye G, Pan J, Xiang J, Huang J, Nie L (2012) QTL mapping for nitrogen-use efficiency and nitrogen-deficiency tolerance traits in rice. Plant and Soil 359, 281–295.
| QTL mapping for nitrogen-use efficiency and nitrogen-deficiency tolerance traits in rice.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38XhtlGmsr3K&md5=4b54290650e764782d21b229301c9c1fCAS |

Weiland RT (1989) Evaluation of maize inbreds for vegetative nitrate uptake and assimilation. Functional Plant Biology 16, 161–168.

Whan A, Robinson N, Lakshmanan P, Schmidt S, Aitken K (2010) A quantitative genetics approach to nitrogen use efficiency in sugarcane. Functional Plant Biology 37, 448–454.
| A quantitative genetics approach to nitrogen use efficiency in sugarcane.Crossref | GoogleScholarGoogle Scholar |

Wolt JD (1994) ‘Soil solution chemistry: applications to environmental science and agriculture.’ (Wiley: New York) 345.

Worku M, Banziger M, Erley GSA, Friesen D, Diallo AO, Horst WJ (2007) Nitrogen uptake and utilization in contrasting nitrogen efficient tropical maize hybrids. Crop Science 47, 519–528.
| Nitrogen uptake and utilization in contrasting nitrogen efficient tropical maize hybrids.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXltlSht7w%3D&md5=ab61fd0e81c5d0d4a74cfa93ebda9a8cCAS |

Xie H-l, Ji H-q, Liu Z-h, Tian G-w, Wang C-l, Hu Y-m, Tang J-h (2009) Genetic basis of nutritional content of stover in maize under low nitrogen conditions. Euphytica 165, 485–493.
| Genetic basis of nutritional content of stover in maize under low nitrogen conditions.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXhsFCmsLjM&md5=13ca9e81c6f8f6bbe01682ffa41691afCAS |

Xu Y, Wang R, Tong Y, Zhao H, Xie Q, Liu D, Zhang A, Li B, Xu H, An D (2014) Mapping QTLs for yield and nitrogen-related traits in wheat: influence of nitrogen and phosphorus fertilization on QTL expression. Theoretical and Applied Genetics 127, 59–72.
| Mapping QTLs for yield and nitrogen-related traits in wheat: influence of nitrogen and phosphorus fertilization on QTL expression.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3sXhsFCqurfO&md5=b7d7baad954affc65b34197cd496f9f4CAS | 24072207PubMed |

Yamaguchi-Shinozaki K, Shinozaki K (1993) Characterization of the expression of a desiccation-responsive rd29 gene of Arabidopsis thaliana and analysis of its promoter in transgenic plants. Molecular & General Genetics 236, 331–340.
| Characterization of the expression of a desiccation-responsive rd29 gene of Arabidopsis thaliana and analysis of its promoter in transgenic plants.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK3sXit1Oiur0%3D&md5=3212d5e99bbff69d3a8c13b86a0a9787CAS |

Yamaguchi-Shinozaki K, Shinozaki K (1994) A novel cis-acting element in an Arabidopsis gene is involved in responsiveness to drought, low-temperature, or high-salt stress. The Plant Cell 6, 251–264.
| A novel cis-acting element in an Arabidopsis gene is involved in responsiveness to drought, low-temperature, or high-salt stress.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2cXlslWqu70%3D&md5=58319ebabe54c735b7078cfc2d1c6212CAS | 8148648PubMed |

Yamaya T, Obara M, Nakajima H, Sasaki S, Hayakawa T, Sato T (2002) Genetic manipulation and quantitative-trait loci mapping for nitrogen recycling in rice. Journal of Experimental Botany 53, 917–925.
| Genetic manipulation and quantitative-trait loci mapping for nitrogen recycling in rice.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD38XivFSntbs%3D&md5=197cdf1d5bc62b429f712dd0a742e17eCAS | 11912234PubMed |

Yan M, Fan X, Feng H, Miller AJ, Shen Q, Xu G (2011) Rice OsNAR2.1 interacts with OsNRT2.1, OsNRT2.2 and OsNRT2.3a nitrate transporters to provide uptake over high and low concentration ranges. Plant, Cell & Environment 34, 1360–1372.
| Rice OsNAR2.1 interacts with OsNRT2.1, OsNRT2.2 and OsNRT2.3a nitrate transporters to provide uptake over high and low concentration ranges.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXhtVOntbvN&md5=875a6f177d06dcd4f5f9a38e271cfdafCAS |

Yanagisawa S, Akiyama A, Kisaka H, Uchimiya H, Miwa T (2004) Metabolic engineering with Dof1 transcription factor in plants: Improved nitrogen assimilation and growth under low-nitrogen conditions. Proceedings of the National Academy of Sciences of the United States of America 101, 7833–7838.
| Metabolic engineering with Dof1 transcription factor in plants: Improved nitrogen assimilation and growth under low-nitrogen conditions.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXktlOksrk%3D&md5=d6ffc0e3bb305b6452e3fc0747a7dce6CAS | 15136740PubMed |

Yang L, Mickelson S, See D, Blake TK, Fischer AM (2004) Genetic analysis of the function of major leaf proteases in barley (Hordeum vulgare L.) nitrogen remobilization. Journal of Experimental Botany 55, 2607–2616.
| Genetic analysis of the function of major leaf proteases in barley (Hordeum vulgare L.) nitrogen remobilization.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXhtVSqsrrN&md5=995cd07fdb5e875335d8e2ae955df72bCAS | 15448176PubMed |

Yau SK, Thurling N (1987) Variation in nitrogen response among spring rape (Brassica napus) cultivars and its relationship to nitrogen uptake and utilization. Field Crops Research 16, 139–155.
| Variation in nitrogen response among spring rape (Brassica napus) cultivars and its relationship to nitrogen uptake and utilization.Crossref | GoogleScholarGoogle Scholar |

Yu JM, Holland JB, McMullen MD, Buckler ES (2008) Genetic design and statistical power of nested association mapping in maize. Genetics 178, 539–551.
| Genetic design and statistical power of nested association mapping in maize.Crossref | GoogleScholarGoogle Scholar |

Yu L-H, Miao Z-Q, Qi G-F, Wu J, Cai X-T, Mao J-L, Xiang C-B (2014) MADS-Box transcription factor AGL21 regulates lateral root development and responds to multiple external and physiological signals. Molecular Plant 7, 1653–1669.
| MADS-Box transcription factor AGL21 regulates lateral root development and responds to multiple external and physiological signals.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC2cXitVKrtrvE&md5=b3e221007c7967651c78b2e279caf0d0CAS | 25122697PubMed |

Zhang HM, Forde BG (1998) An Arabidopsis MADS box gene that controls nutrient-induced changes in root architecture. Science 279, 407–409.
| An Arabidopsis MADS box gene that controls nutrient-induced changes in root architecture.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK1cXmsVShtA%3D%3D&md5=ebaf4a2a90bd4b98c22f521e897ebd59CAS |

Zhang N, Gibon Y, Gur A, Chen C, Lepak N, Höhne M, Zhang Z, Kroon D, Tschoep H, Stitt M, Buckler E (2010) Fine quantitative trait loci mapping of carbon and nitrogen metabolism enzyme activities and seedling biomass in the maize IBM mapping population. Plant Physiology 154, 1753–1765.
| Fine quantitative trait loci mapping of carbon and nitrogen metabolism enzyme activities and seedling biomass in the maize IBM mapping population.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXhsF2jsbbK&md5=9df6732d9a8d20167f9775a5d9ef8171CAS | 20971858PubMed |

Zhang N, Gibon Y, Wallace JG, Lepak N, Li P, Dedow L, Chen C, So YS, Kremling K, Bradbury PJ, Brutnell T, Stitt M, Buckler ES (2015) Genome-wide association of carbon and nitrogen metabolism in the maize nested association mapping population. Plant Physiology 168, 575–583.
| Genome-wide association of carbon and nitrogen metabolism in the maize nested association mapping population.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC2MXhtVGnsr7I&md5=1a0fb48068c75ceeee1196940a66d335CAS | 25918116PubMed |

Zhao C-f, Zhou L-h, Zhang Y-d, Zhu Z, Chen T, Zhao Q-y, Yao S, Yu X, Wang C-l (2014) QTL mapping for seedling traits associated with low-nitrogen tolerance using a set of advanced backcross introgression lines of rice. Plant Breeding 133, 189–195.
| QTL mapping for seedling traits associated with low-nitrogen tolerance using a set of advanced backcross introgression lines of rice.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC2cXlsF2gsL4%3D&md5=f1f9f35d82c7857ad64054df3f9b20f7CAS |