Drought-Induced Adaptive Intergenerational Plasticity Boosts Grain Yield in Winter Wheat (Triticum aestivum L.)

Intergenerational plasticity namely parental environmental induction of offspring phenotypic changes, offers a promising pathway for drought adaptation, but the induction mechanisms and adaptive mechanisms are insufficient. To address this, we integrated multi-season soil pot and field experiments with multi-omics analyses to systematically evaluate the intergenerational plasticity of winter wheat. Results showed that parental drought applied during jointing (gametogenesis) significantly augmented offspring grain yield by 33% under severe drought in soil pot, whereas post-anthesis drought failed to enhance offspring yield (-5%, p > 0.05), when compared to the common irrigation regime. Among nine cultivars tested, only JM22, China's most widely cultivated cultivar, exhibited synergistic physiological improvements and the strongest adaptive intergenerational plasticity, increasing grain yield by 10.5% under field drought conditions. JM22's offspring from drought-primed parents showed enhanced assimilate transport, delayed leaf senescence, improved root plasticity, and higher water-use efficiency. Remarkably, two consecutive generations of drought exposure further amplified this yield benefit to 15.2%. Genome-wide DNA hypomethylation and transcriptomic reprogramming underpinned this enhanced resilience. Our study reveals that adaptive intergenerational plasticity in wheat is driven by a finely-tuned resource re-allocation strategy that balances drought defense with reproductive growth, a process consolidated over generations through epigenetic mechanisms.