Department of biological sciences, College of Agronomy, Henan University of Science and Technology, Luoyang, Henan Province, China.
Institute of Plant Protection Research, Henan Academy of Agricultural Sciences, Henan Key Laboratory for Control of Crop Diseases and Insect Pests, IPM Key Laboratory in Southern Part of North China for Ministry of Agriculture, Zhengzhou, Henan Province, China.
PLoS One. 2018 Jun 28;13(6):e0198878. doi: 10.1371/journal.pone.0198878. eCollection 2018.
The effect of plant population density (PPD) and root-induced leaf cytokinin on the compensatory growth of potted corn seedlings during post-drought rewatering was investigated. The study design comprised four treatments: (1) wetness with low PPD, (2) wetness with high PPD, (3) rewatering with low PPD, and (4) rewatering with high PPD. Results showed that drought stress restrained the growth of corns. By contrast, rewatering enhanced the net photosynthetic rate and growth of corns. During the 8 days of rewatering, compensatory growth during post-drought rewatering occurred in corns with high PPD; however, such compensatory growth did not occur in corns with low PPD. Zeatin riboside concentrations in leaves and xylem saps were significantly higher under rewatering treatment than those under wet treatment. High leaf cytokinin concentration accelerated corn growth. The coefficients of variation and Gini-coefficient of wet treatment were significantly higher than those of rewatering treatment under high PPD, demonstrating that intense intraspecific competition occurred in the wet treatment. Extreme intraspecific competition negatively affected net photosynthetic rate. In brief, the interactions between root-induced leaf cytokinin and weak intraspecific competition promoted the compensatory growth under high PPD.
研究了植物种群密度（PPD）和根诱导的叶片细胞分裂素对干旱后复水过程中盆栽玉米幼苗补偿生长的影响。研究设计包括四种处理：（1）低 PPD 条件下保持湿润，（2）高 PPD 条件下保持湿润，（3）低 PPD 条件下复水，（4）高 PPD 条件下复水。结果表明，干旱胁迫抑制了玉米的生长。相比之下，复水增强了玉米的净光合速率和生长。在复水的 8 天内，高 PPD 条件下的玉米发生了干旱后复水的补偿生长；然而，低 PPD 条件下的玉米没有发生这种补偿生长。复水处理下叶片和木质部汁液中的玉米素核苷浓度明显高于湿润处理。高叶片细胞分裂素浓度加速了玉米的生长。高 PPD 条件下，湿润处理的变异系数和基尼系数明显高于复水处理，表明在湿润处理中存在强烈的种内竞争。极端的种内竞争对净光合速率有负面影响。总之，根诱导的叶片细胞分裂素与弱种内竞争之间的相互作用促进了高 PPD 下的补偿生长。
