ABA is a plant hormone produced in plants under drought stress. On one hand, it causes the plant to conserve its water status; on the other hand, it reduces growth and productivity. This opinion review examines the available data on ABA and attempts to resolve this conundrum by formulating an appropriate crop plant phenotypic ABA ideotype for breeders to pursue within different dryland stress environments.

Pre-anthesis water-deficit stress causes detrimental effects on the production of crops such as durum wheat in rain-fed areas. In stress tolerant varieties, the regulation of microRNA160 and the mRNA that it targets, auxin response factors, are potentially associated with the unaffected leaf relative water content and chlorophyll content, and the co-ordinated control of stomatal aperture, which ultimately contribute to the maintenance of grain number and yield. Together, these findings suggest the importance of durum microRNA regulatory modules in water stress responses and provide useful information for improving stress tolerance in breeding.

In contrast to their ancestors, vascular plants do not have a Na⁺ pump. The lack of a Na⁺ pump might give a hint as to why vascular plants are so sensitive to salinity. In this minireview, we discuss the feasibility of introducing a Na⁺ pump to increase the salt tolerance of vascular plants.

Plant adaptive potential is critically dependent upon efficient communication and co-ordination of resource allocation and signalling between above- and below-ground plant parts by various physical, chemical and molecular signals. This review summarises the current knowledge of these signalling mechanisms, and reveals the hierarchy and discuss integration of these signalling components, to enable optimal plant functioning in a dynamic environment.

In higher plants, local damage induces a unique electrical signal: variation potential, which influences numerous physiological processes; however, its role in plant life is not clear. We showed that variation potential decreases PSI damage, increases PSII damage and raises the resistance of the whole plant under heating. Thus variation potential can increase the probability of plant survival under high temperatures.

Sugars are not only substrates for diverse metabolic pathways, but also powerful signalling molecules that regulate developmental processes such as flowering. Sucrose produced from mature leaves is translocated through phloem to sink organs. Sugars leaked from phloem may also enter the xylem stream. Here, we assessed advances in understanding how carbon (C) allocation and sugar signalling co-ordinate shoot–root growth. The analyses provided new insights to this topic including the coupling between C and nitrogen (N) uptake and the regulatory proteins and hormonal pathways involved in balancing shoot–root C–N status.

Rice seeds are able to germinate under water, also thanks to their ability to produce α-amylase under O₂ shortage, thus allowing starch degradation. Calcineurin B-like interacting protein kinase 15 (CIPK15) was previously identified as a positive regulator of α-amylase induction during anaerobic germination. In this study, we describe calcineurin B-like proteins 4 (CBL4) as a CIPK15 partner under low O₂.

Distinct proteins that are main actors in neurotransmission in animals exist also in other living organism. Extensive studies in plants revealed an involvement of these so-called glutamate receptors in fundamental signalling events covering the whole plant life cycle. This review presents a comprehensive theory of their role in Arabidopsis thaliana by compiling, condensing and re-evaluating more than 15 years of research.

Water limitation is known to affect plant growth and yield. To begin dissecting time-dependent effects of water limitation in Arabidopsis, we combined high-throughput phenomics and ionomics. These two approaches allowed us to quantify the negative effects of water limitation at critical points during plant development.

High night temperature (HNT) can significantly reduce rice yield and quality. Flowering dynamics, spikelet tissue temperature determines seed-set among diverse rice genotypes exposed to early and/or late night temperature stress. Documented for the first time is a critical night temperature threshold of 27°C beyond which reduction in spikelet fertility is induced. The different sensitivities to HNT of cultivars for spikelet fertility and quality will complement plant breeding efforts targeted towards enhancing resilience of rice cultivars to warmer climates.

In this work we used halophyte species Chenopodium quinoa to investigate the causal relationship between salinity and oxidative stress tolerance in plants. The most dramatic changes observed were in rutin, a flavonoid with non-enzymatic antioxidant activity. Exogenous application of rutin to glycophyte bean leaves improved tissue tolerance by mitigating reactive oxygen species-induced K⁺ efflux from the cell.

Breeding crops for water conservation leads to hotter leaves under hot, high-light conditions and thus, the potential for heat-related damage or photoinhibition to the photosynthesis apparatus. However, damaging temperatures were not reached in soybeans under soil water deficits or high air temperature, and no sign of prolonged photosynthetic damage was evident. It appears that for the broad range of conditions measured in this study, water conservation did not have negative consequences on photosynthetic capacity.