Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium.
VIB Center for Plant Systems Biology, 9052 Ghent, Belgium.
Plant Physiol. 2021 Jun 11;186(2):1336-1353. doi: 10.1093/plphys/kiab155.
Drought at flowering and grain filling greatly reduces maize (Zea mays) yield. Climate change is causing earlier and longer-lasting periods of drought, which affect the growth of multiple maize organs throughout development. To study how long periods of water deficit impact the dynamic nature of growth, and to determine how these relate to reproductive drought, we employed a high-throughput phenotyping platform featuring precise irrigation, imaging systems, and image-based biomass estimations. Prolonged drought resulted in a reduction of growth rate of individual organs-though an extension of growth duration partially compensated for this-culminating in lower biomass and delayed flowering. However, long periods of drought did not affect the highly organized succession of maximal growth rates of the distinct organs, i.e. leaves, stems, and ears. Two drought treatments negatively affected distinct seed yield components: Prolonged drought mainly reduced the number of spikelets, and drought during the reproductive period increased the anthesis-silking interval. The identification of these divergent biomass and yield components, which were affected by the shift in duration and intensity of drought, will facilitate trait-specific breeding toward future climate-resilient crops.
花期和灌浆期干旱会极大地降低玉米（Zea mays）的产量。气候变化导致干旱期提前且持续时间更长，影响了玉米在整个发育过程中多个器官的生长。为了研究长时间的水分亏缺如何影响生长的动态特性，并确定其与生殖干旱的关系，我们采用了一种高通量表型平台，该平台具有精确的灌溉、成像系统和基于图像的生物量估计功能。长时间的干旱导致单个器官的生长速率降低——尽管生长持续时间的延长部分弥补了这一点——最终导致生物量降低和开花延迟。然而，长时间的干旱并没有影响不同器官（即叶片、茎和穗）最大生长速率的高度有序的连续。两种干旱处理对不同的种子产量构成因素有负面影响：长时间的干旱主要减少了小穗的数量，而生殖期的干旱增加了抽丝期。这些不同的生物量和产量组成部分的鉴定，受干旱持续时间和强度变化的影响，将有助于针对未来具有气候恢复力的作物进行特定性状的选育。
