Differences in dehydration tolerance affect survival of white clover (Trifolium repens) and lucerne (Medicago sativa) during a drying cycle
Mark R. Norton
A B C , Guangdi D. Li A B , Binbin Xu A , Andrew Price A , Peter Tyndall A and Richard C. Hayes A B
A NSW Department of Primary Industries, Wagga Wagga Agricultural Institute, Pine Gully Road, Wagga Wagga, NSW 2650, Australia.
B Graham Centre for Agricultural Innovation (an Alliance between NSW Department of Primary Industries and Charles Sturt University), Albert Pugsley Place, Wagga Wagga, NSW 2650, Australia.
C Corresponding author. Email: mark.norton@dpi.nsw.gov.au
Crop and Pasture Science - https://doi.org/10.1071/CP20300
Submitted: 10 August 2020 Accepted: 15 January 2021 Published online: 9 April 2021
Abstract
There is very little robust, experimentally based knowledge comparing drought tolerance of one legume species with another. Dehydration tolerance and plant survival of the perennial legumes white clover (Trifolium repens L., considered quite sensitive to drought) and lucerne (Medicago sativa L., considered drought tolerant) were compared in a drying cycle experiment conducted in pots in a glasshouse, with the deep rooting of lucerne constrained. White clover used more soil water, drying the pots to a final soil gravimetric water content (θg) of 4.7%, compared with 8.3% in lucerne pots. Rates of water use were also different: white clover used 0.47% of θg per day and lucerne 0.3%. The more conservative water use allowed lucerne to survive for longer into the drying cycle than white clover. Lucerne partitioned more of its total dry matter into root growth and had much higher root:shoot ratios than white clover. Leaf/stolon elongation is one of the first plant processes to cease as water deficit increases; however, elongation was greater in white clover than lucerne at the beginning of the drying cycle, and this trend continued until lower soil water contents were reached. Conversely, leaf senescence generally commenced at quite high levels of water stress and progressed more rapidly to complete senescence in white clover than in lucerne. Lucerne retained tissue relative water content at a higher level than white clover, with final minimum values of 25% and 13.6%, respectively. In lucerne, 50% mortality was observed at θg of 9%, compared with 6% in white clover, albeit with greater variability. In conclusion, lucerne maintained a higher relative water content than white clover even though it endured the drying cycle for longer and without access to water at depth, evidence of its superior dehydration avoidance and better adaptation to dry conditions. However, white clover was more able to extract water from surface soil layers. This study provides valuable insight into the adaptive traits of both species and identifies some traits that might be useful in the quest to improve white clover adaptation.
Keywords: drought, dehydration avoidance, root:shoot ratio, leaf elongation, leaf senescence.
References
Annicchiarico P, Barrett B, Brummer EC, Julier B, Marshall AH (2015) Achievements and challenges in improving temperate perennial forage legumes. Critical Reviews in Plant Sciences 34, 327–380.| Achievements and challenges in improving temperate perennial forage legumes.Crossref | GoogleScholarGoogle Scholar |
Ayres JF, Fitzgerald RD, Jahufer MZZ, Norton MR (1992) White clover improvement for the Australian sheep industry. Wool Technology and Sheep Breeding 39, 162–167.
Ayres JF, Caradus JR, Murison RD, Lane LA, Woodfield DR (2007) Grasslands Trophy: a new white clover (Trifolium repens L.) cultivar with tolerance of summer moisture stress. Australian Journal of Experimental Agriculture 47, 110–115.
| Grasslands Trophy: a new white clover (Trifolium repens L.) cultivar with tolerance of summer moisture stress.Crossref | GoogleScholarGoogle Scholar |
Barrs HD, Weatherley PE (1962) A re-examination of the relative turgidity technique for estimating water deficits in leaves Australian Journal of Biological Sciences 15, 413–428.
| A re-examination of the relative turgidity technique for estimating water deficits in leavesCrossref | GoogleScholarGoogle Scholar |
Blum A (1996) Crop responses to drought and the interpretation of adaptation. Plant Growth Regulation 20, 135–148.
| Crop responses to drought and the interpretation of adaptation.Crossref | GoogleScholarGoogle Scholar |
Bolger TP, Rivelli AR, Garden DL (2005) Drought resistance of native and introduced perennial grasses of south-eastern Australia. Australian Journal of Agricultural Research 56, 1261–1267.
| Drought resistance of native and introduced perennial grasses of south-eastern Australia.Crossref | GoogleScholarGoogle Scholar |
Burch GJ, Johns GG (1978) Root absorption of water and physiological responses to water deficits by Festuca arundinacea Schreb. and Trifolium repens L. Australian Journal of Plant Physiology 5, 859–871.
Caradus JR (1986) World checklist of white clover varieties. New Zealand Journal of Experimental Agriculture 14, 119–164.
| World checklist of white clover varieties.Crossref | GoogleScholarGoogle Scholar |
Caradus JR, Woodfield DR (1998) Genetic control of adaptive root characteristics in white clover. Plant and Soil 200, 63–69.
| Genetic control of adaptive root characteristics in white clover.Crossref | GoogleScholarGoogle Scholar |
Cresswell HP (2002) The soil water characteristic. In ‘Soil physical measurement and interpretation for land evaluation’. Australian Soil and Land Survey Handbook Series Vol. 5. (Eds N McKenzie, K Coughlan, H Cresswell) pp. 59–84. (CSIRO Publishing: Melbourne, Vic.)
Elhaak MA, Elshourbagy MN, Ayyad MA (1991) Adaptive responses of root systems of some native and cultivated species to desert conditions. Journal of Agronomy and Crop Science-Zeitschrift Fur Acker Und Pflanzenbau 167, 176–183.
| Adaptive responses of root systems of some native and cultivated species to desert conditions.Crossref | GoogleScholarGoogle Scholar |
Hart AL (1987) Physiology. In ‘White clover’. (Eds MJ Baker, WM Williams) pp. 125–151. (CAB International: Wallingford, UK)
Hoffmann JD, Eberbach PL, Virgona JM, Katupitiya A (2003) Conservative water use by lucerne. In ‘Solutions for a new environment. Proceedings 11th Australian Agronomy Conference’. 2–6 February 2003. Geelong, Vic. (Australian Society of Agronomy)
Hsiao TC (1973) Plant responses to water stress. Annual Review of Plant Physiology 24, 519–570.
Isbell RF (1996) ‘The Australian Soil Classification.’ (CSIRO Publishing: Melbourne, Vic.)
Johns GG (1978) Transpirational, leaf area, stomatal and photosynthetic responses to gradually induced water stress in four temperate herbage species. Australian Journal of Plant Physiology 5, 113–125.
Lane LA, Ayres JF, Lovett JV (2000) The pastoral significance, adaptive characteristics, and grazing value of white clover (Trifolium repens L.) in dryland environments in Australia: a review. Australian Journal of Experimental Agriculture 40, 1033–1046.
| The pastoral significance, adaptive characteristics, and grazing value of white clover (Trifolium repens L.) in dryland environments in Australia: a review.Crossref | GoogleScholarGoogle Scholar |
Lelièvre F, Norton MR, Volaire F (2008) Perennial grasses in rainfed Mediterranean farming systems. Current and potential role. Cahiers Options Méditerranéennes 79, 137–146.
Ludlow MM (1989) Strategies of response to water stress. In ‘Structural and functional responses to environmental stresses: water shortage’. (Eds KH Kreeb, H Richter, TM Hinckley) pp. 269–281. (SPB Academic Publishing: The Hague)
Norton MR, FitzGerald RD (1993) Nationwide field testing of genotypes for white clover improvement. Australian Plant Introduction Review 24, 42–53.
Norton MR, Lelièvre F, Volaire F (2014) Measuring dehydration tolerance in pasture grasses to improve drought survival. Crop & Pasture Science 65, 828–840.
| Measuring dehydration tolerance in pasture grasses to improve drought survival.Crossref | GoogleScholarGoogle Scholar |
Peoples MB, Baldock JA (2001) Nitrogen dynamics of pastures: nitrogen fixation inputs, the impact of legumes on soil nitrogen fertility, and the contributions of fixed nitrogen to Australian farming systems. Australian Journal of Experimental Agriculture 41, 327–346.
| Nitrogen dynamics of pastures: nitrogen fixation inputs, the impact of legumes on soil nitrogen fertility, and the contributions of fixed nitrogen to Australian farming systems.Crossref | GoogleScholarGoogle Scholar |
Sinclair TR, Ludlow MM (1985) Who taught plants thermodynamics? The unfulfilled potential of plant water potential. Australian Journal of Plant Physiology 33, 213–217.
Sinclair TR, Ludlow MM (1986) Influence of soil water supply on the plant water balance of four tropical grain legumes. Australian Journal of Plant Physiology 13, 329–341.
Smith A, Morrison ARJ (1983) A deep rooted white clover for South African conditions. In ‘Proceedings of the Grassland Society of South Africa’. Vol. 18, pp. 50–52. (Grassland Society of Southern Africa)
Turner NC (1986) Adaptation to water deficits: a changing perspective. Australian Journal of Plant Physiology 13, 175–190.
Volaire F (2008) Plant traits and functional types to characterise drought survival of pluri-specific perennial herbaceous swards in Mediterranean areas. European Journal of Agronomy 29, 116–124.
| Plant traits and functional types to characterise drought survival of pluri-specific perennial herbaceous swards in Mediterranean areas.Crossref | GoogleScholarGoogle Scholar |
Volaire F, Lelievre F (2001) Drought survival in Dactylis glomerata and Festuca arundinacea under similar rooting conditions in tubes. Plant and Soil 229, 225–234.
| Drought survival in Dactylis glomerata and Festuca arundinacea under similar rooting conditions in tubes.Crossref | GoogleScholarGoogle Scholar |
Volaire F, Conejero G, Lelievre F (2001) Drought survival and dehydration tolerance in Dactylis glomerata and Poa bulbosa. Australian Journal of Plant Physiology 28, 743–754.
