A gene‐stacking approach to overcome the trade‐off between drought stress tolerance and growth in Arabidopsis (Plant J)

In the face of increasing incidence of drought events, developing drought-tolerant plants becomes urgent matter. However, the increase in drought tolerance often coincides with the significant reduction of plant size, as in the case of overexpressing DEHYDRATION-RESPONSIVE ELEMENT-BINDING PROTEIN 1A (DREB1A). Kudo et al. combined DREB1A with genes promoting plant growth, including gibberellin biosynthesis enzyme GA REQUIRING5 (GA5) and PHYTOCHROME INTERACTING FACTOR4 (PIF4) which regulates cell growth. Double overexpression lines developed larger rosettes compared to DREB1A lines, but the drought tolerance was maintained only in GA5 DREB1A lines, due to downregulation of DREB1A expression in PIF4 DREB1A lines. The detailed analysis of the double overexpression lines revealed upregulation of tricarboxylic acid cycle, increased metabolic rates and altered homeostasis of auxin and gibberellin. This study exemplifies that gene stacking of drought resistance and growth genes can be successfully applied in molecular breeding for enhanced drought tolerance. (Summary by Magdalena Julkowska) Plant J 10.1111/tpj.14110