文献类型： 外文期刊

作者： 王志;刘正;刘瑞显;周宝元;王新兵;丁在松;张仁和;李从锋;赵明

关键词： 乙烯利;小花增长;籽粒败育;光合作用;玉米

期刊名称： FIELD CROPS RESEARCH

ISSN： 0378-4290

年卷期： 2025 年

页码：

收录情况： SCIE（2025版）

摘要： Context: Ethephon is used worldwide to improve the lodging resistance of maize, especially under high planting density, while limits grain formation. The mechanism of alleviating/eliminating the negative effects of ethephon on grain formation is still controversial. Objective: The purpose of this study was to improve the lodging resistance regulation scheme to explore the effects of combined application of ethephon and synergist on the photosynthetic performance and grain for mation of maize population. 1 , LD; high density, 97,500 plants ha Methods: Xianyu335 was used as the experimental material at two planting densities (low density, 67,500 plants ha 1 , HD) and three chemical regulation modes (CK: clean water; ETH: spraying ethephon at 8th leaf stage; PHS: spraying ethephon at 8th leaf stage and spraying synergist at 11th leaf stage) at each planting density. The experiment assessed photosynthetic performance (chlorophyll, leaf area, net photosynthetic rate, etc.), dry matter, floret growth and development parameters, grain filling parameters, and yield. Results: Under LD conditions, PHS did not significantly increase grain yield. Under HD conditions without lod ging, ETH yield decreased by 14.09 %, while PHS yield increased by 12.51 %; under HD conditions with lodging, ETH yield increased by 25.53 % and PHS yield increased by 40.28 %. PHS under HD reduced chlorophyll- degrading enzyme activity and increased carbon assimilation key enzyme activity, resulting in 15.02 % and 60.18 % increases in chlorophyll content and net photosynthetic rate, respectively, which promoted dry matter accumulation at physiological maturity by 21.28 %. Moreover, PHS increased the number of fertilized florets by 6.01 % and reduced abortive grains 54.50 %, respectively, leading to a 14.75 % increase in grain number, compared with CK. At the same time, the leaf area index at physiological maturity increased by 29.66 % under PHS. This improvement led to a higher filling rate during the later stages of maize growth and extended the f illing period by approximately 8.5 days. As a result, PHS increased grain weight by 6.62 % compared with CK. Conclusions: Compared with CK, PHS significantly enhances the net photosynthetic rate and delays leaf senes cence, which increases the number and weight of grains while mitigating grain abortion driven by young ear growth and grain-filling, ultimately promoting grain yield of maize, especially under high planting density. Implications: PHS is a possible management method to achieve the common progress of lodging resistance and grain yield, which will be beneficial in promoting the further improvement of maize yield.

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