Jing Lanshu, Weng Baisha, Yan Denghua, Zhang Shanjun, Bi Wuxia, Yan Siying
State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing, China.
College of Hydrology and Water Resources, Hohai University, Nanjing, China.
Front Plant Sci. 2023 Jan 25;14:1016993. doi: 10.3389/fpls.2023.1016993. eCollection 2023.
Crop resilience refers to the adaptive ability of crops to resist drought at a certain level. Currently, most of the research focuses on the changes in root or photosynthesis traits of crops after drought and rehydration. Still, the persistence effect (drought period (T2) - rehydration period (T3) - harvest period (T4)) of drought stress on crops and quantitative estimation of resilience is still unclear. Field experiments were conducted in this study to determine the persistence effects on above-ground and below-ground growth indicators of summer maize at different levels and durations of drought. Next, an evaluation method for integrated resilience of summer maize was proposed, and a quantitative assessment of integrated resilience was made by Principal Component Analysis (PCA) and resilience index calculation. The results showed that the resilience of summer maize decreased with increasing drought levels, which persisted until harvest. Although summer maize resilience was strong after rewatering under light drought (DR1), declined after sustained rewatering. At the same time, production had decreased. However, a specific drought duration could improve the resilience of summer maize under light drought conditions. In particular, leaf biomass and root growth in the 30-50 cm layer could be enhanced under long duration light drought (LDR1), thus improving summer maize resilience and yield. Thus, under water shortage conditions, a certain level and duration drought could improve the resilience and yield of summer maize, which would persist until harvest. Clarifying the persistent effects on the growth indicators of summer maize and quantitatively evaluating the resilience of summer maize could improve agricultural food production and water use efficiency.
作物韧性是指作物在一定程度上抵抗干旱的适应能力。目前，大多数研究集中在干旱和复水后作物根系或光合特性的变化上。然而，干旱胁迫对作物的持续影响（干旱期（T2）-复水期（T3）-收获期（T4））以及韧性的定量评估仍不清楚。本研究通过田间试验，确定不同干旱水平和持续时间对夏玉米地上和地下生长指标的持续影响。其次，提出了夏玉米综合韧性评价方法，并通过主成分分析（PCA）和韧性指数计算对综合韧性进行了定量评估。结果表明，夏玉米的韧性随着干旱水平的增加而降低，这种影响一直持续到收获期。虽然轻度干旱（DR1）复水后夏玉米韧性较强，但持续复水后韧性下降，同时产量也有所降低。然而，特定的干旱持续时间可以提高轻度干旱条件下夏玉米的韧性。特别是在长期轻度干旱（LDR1）条件下，30-50厘米土层的叶片生物量和根系生长可以得到增强，从而提高夏玉米的韧性和产量。因此，在缺水条件下，一定水平和持续时间的干旱可以提高夏玉米的韧性和产量，这种影响会一直持续到收获期。明确干旱对夏玉米生长指标的持续影响并定量评估夏玉米的韧性，有助于提高农业粮食产量和水分利用效率。
