Division of Plant Sciences and Interdisciplinary Plant Group, College of Agriculture Food and Natural Resources, Christopher S. Bond Life Sciences Center, University of Missouri, 1201 Rollins Street, Columbia, Missouri, 65201, USA.
Physiol Plant. 2021 Jan;171(1):66-76. doi: 10.1111/ppl.13203. Epub 2020 Sep 17.
Episodes of prolonged drought coupled with heat waves (i.e. drought and heat combination) can have a devastating impact on agricultural production and crop yield. It is therefore not surprising that improving tolerance to drought and heat combination has been a major goal for breeders and biotech companies. Although much is known about the physiological and molecular responses of vegetative tissues to a combination of drought and heat stress, less is known about the impact of this stress combination on yield and different yield components. Here, we used a meta-analysis approach to synthesize results from over 120 published case studies of crop responses to combined drought and heat stress. Our findings reveal that drought and heat stress combination significantly impacts yield by decreasing harvest index, shortening the life cycle of crops, and altering seed number, size and composition. Furthermore, these impacts are more severe when the stress combination is applied during the reproductive stage of plants. We further identify differences in how legumes and cereals respond to the stress combination and reveal that utilizing C3 or C4 metabolism may not provide an advantage to plants during stress combinations. Taken together our study highlights a need to focus future studies, as well as breeding efforts, on crop responses to drought and heat combination at the reproductive stage of different crop species.
长时间干旱加上热浪（即干旱和热组合）会对农业生产和作物产量造成毁灭性的影响。因此，提高对干旱和热组合的耐受性一直是育种家和生物技术公司的主要目标。尽管人们对植物组织对干旱和热胁迫组合的生理和分子反应有了很多了解，但对这种胁迫组合对产量和不同产量成分的影响了解较少。在这里，我们使用荟萃分析方法综合了 120 多个关于作物对干旱和热胁迫组合反应的已发表案例研究的结果。我们的研究结果表明，干旱和热胁迫组合通过降低收获指数、缩短作物生命周期以及改变种子数量、大小和组成，显著影响产量。此外，当胁迫组合应用于植物的生殖阶段时，这些影响更为严重。我们进一步确定了豆科植物和禾本科植物对胁迫组合的反应差异，并揭示了在胁迫组合期间利用 C3 或 C4 代谢可能不会为植物提供优势。总之，我们的研究强调需要将未来的研究以及育种工作重点放在不同作物物种生殖阶段对干旱和热组合的作物反应上。
