Climate‐resilient crops: Lessons from xerophytes

Abstract

SUMMARYDeveloping climate‐resilient crops is critical for future food security and sustainable agriculture under current climate scenarios. Of specific importance are drought and soil salinity. Tolerance traits to these stresses are highly complex, and the progress in improving crop tolerance is too slow to cope with the growing demand in food production unless a major paradigm shift in crop breeding occurs. In this work, we combined bioinformatics and physiological approaches to compare some of the key traits that may differentiate between xerophytes (naturally drought‐tolerant plants) and mesophytes (to which the majority of the crops belong). We show that both xerophytes and salt‐tolerant mesophytes have a much larger number of copies in key gene families conferring some of the key traits related to plant osmotic adjustment, abscisic acid (ABA) sensing and signalling, and stomata development. We show that drought and salt‐tolerant species have (i) higher reliance on Na for osmotic adjustment via more diversified and efficient operation of Na+/H+ tonoplast exchangers (NHXs) and vacuolar H+‐ pyrophosphatase (VPPases); (ii) fewer and faster stomata; (iii) intrinsically lower ABA content; (iv) altered structure of pyrabactin resistance/pyrabactin resistance‐like (PYR/PYL) ABA receptors; and (v) higher number of gene copies for protein phosphatase 2C (PP2C) and sucrose non‐fermenting 1 (SNF1)‐related protein kinase 2/open stomata 1 (SnRK2/OST1) ABA signalling components. We also show that the past trends in crop breeding for Na+ exclusion to improve salinity stress tolerance are counterproductive and compromise their drought tolerance. Incorporating these genetic insights into breeding practices could pave the way for more drought‐tolerant and salt‐resistant crops, securing agricultural yields in an era of climate unpredictability.

Understanding the role of boron in plant adaptation to soil salinity

“…Hence, dozens of genes should be modified in high-yielding varieties to make it work (Chen et al, 2023). At the same time, most papers/ research programs attempted to find some sort of "silver bullet" targeting one (or 2-3 maximum, in a few rare cases) gene(s) at a time.…”

“…It's not unexpected since the ability to tolerate salinity is determined by various sub‐traits that function in a well‐coordinated manner at the cellular and tissue levels. Hence, dozens of genes should be modified in high‐yielding varieties to make it work (Chen et al, 2023). At the same time, most papers/research programs attempted to find some sort of “silver bullet” targeting one (or 2–3 maximum, in a few rare cases) gene(s) at a time.…”

“…As mentioned above, B availability affects (directly or indirectly) various processes, including cell wall and membrane integrity, cell division and elongation, reproductive growth, synthesis of carbohydrates and proteins, and hormonal production and synthesis (Kohli et al, 2023; Chen et al, 2023). Most (if not all) of these processes are also affected by salt.…”

Stress combination: from genes to ecosystems

“…The authors explain how climate change, industrial pollution, and global warming elevate the frequency, complexity, and intensity of multiple stress combinations, and discuss the impacts of MFSC on agriculture, microbiomes, and ecosystems worldwide. Chen et al (2024) discuss in their review the combination of drought and salinity stresses. The authors address the challenges this stress combination poses to agriculture and compare some of the key traits that differentiate between xerophytes (naturally droughttolerant plants) and mesophytes (majority of the crops).…”