机采棉化学脱叶伴随着剧烈的乙烯及细胞分裂素信号响应  

Chemical Defoliation of Machine-Harvested Cotton was Accompanied by Intense Ethylene and Cytokinin Signal Responses

作　　者：高瑜 徐娇 张冰 孙伟男 杨细燕[1] Gao Yu;Xu Jiao;Zhang Bing;Sun Weinan;Yang Xiyan(National Key Laboratory of Crop Genetic Improvement,Huazhong Agricultural University,Wuhan 430070,China)

机构地区：[1]华中农业大学作物遗传改良国家重点实验室,武汉430070

出　　处：《棉花学报》2020年第6期491-500,共10页Cotton Science

基　　金：国家重点研发计划(2018YFD1000907)。

摘　　要：【目的】化学脱叶是棉花机采前必需的技术措施,脱叶效果直接影响棉花机采的效率和纤维品质,解析脱叶剂调控脱叶的分子机理可以有效地指导机采棉品种的选育。【方法】选取200份棉花种质资源在温室种植,根据初花期脱叶剂处理后第4天的脱叶率筛选出对脱叶剂敏感性不同的材料,并在大田种植的吐絮期进行脱叶剂处理,统计处理后第7天的脱叶率确定脱叶效果。在脱叶剂敏感和不敏感材料中各选取2个,对脱叶剂处理后第1天和第3天离层进行取样,通过实时荧光定量聚合酶链反应(Quantitative real-time polymerase chain reaction,qRT-PCR)检测乙烯、细胞分裂素和水解酶相关基因的表达。【结果】通过温室及大田筛选,得到脱叶剂敏感材料和不敏感材料各6个;qRT-PCR研究发现,大部分乙烯相关基因、细胞分裂素相关基因及水解酶相关基因在脱叶剂处理后呈现不同的表达模式,且在不同敏感性材料中差异表达。【结论】不同棉花种质对脱叶剂响应存在差异,这可能是细胞分裂素和乙烯相关基因差异表达的结果。[Objective]Chemical defoliation is a necessary technical measure for machine-harvested cotton,and the effect of chemical defoliation directly affects the efficiency of mechanical-picking and fiber quality.Study on the molecular mechanism of defoliant in regulating defoliation could effectively guide the screening and improvement of defoliant-sensitive cotton germplasms.[Method]In this study,200 cotton accessions were collected and planted in greenhouse,and treated with defoliant at the early flowering stage.Different varieties with high or low sensitivity to defoliant were selected according to the defoliation rate on the 4th day after treatment.The selected cotton varieties were also treated with defoliant at the boll opening stage in the field,and the defoliation rate on the 7th day after treatment was calculated.Meanwhile,samples from the abscission zone of the selected varieties were collected on the first and third day after treatment.And the expression of ethylene-,cytokinin-and hydrolase-related genes were analyzed by quantitative real-time polymerase chain reaction(qRT-PCR).[Result]Six defoliant sensitive and 6 insensitive varieties were selected from greenhouse and field tests.According to the qRT-PCR results,cytokinin-related genes,ethylene-related genes and hydrolase-related genes showed different expression patterns following defoliant treatment in different varieties,and most of these genes showed significant different expression in the defoliant sensitive and insensitive varieties.[Conclusion]This study indicates that different cotton germplasms respond to differently to defoliant,which might be the result of differential expression of cytokinin-and ethylene-related genes.

关 键 词：棉花 细胞分裂素 脱叶剂 脱叶率 乙烯 

分 类 号：S562[农业科学—作物学]