化学打顶对棉花冠层结构指标及产量形成的影响

Effect of Chemical Multi-topping on Canopy Structure Index and Yield Formation in Cotton

【目的】研究棉花喷施化学打顶剂对植株形态、冠层结构特性的影响,探讨应用化学打顶剂调节棉花株型、冠层结构及产量构成因子的效应,为棉花化学打顶技术的应用提供理论依据。【方法】选用棉花品种为新陆早45号、45-21(品系),在田间自然条件下,以人工打顶的棉花为对照,研究喷施化学打顶剂对棉花农艺性状、冠层结构指标及产量形成的影响。【结果】与人工打顶相比,化学打顶株高、主茎节数增加、株宽变小,株形紧凑;不同部位DIFN较大,叶面积指数较高,不同冠层光吸收较人工打顶的均匀,中、下部冠层光吸收率高;不同打顶剂表现为氟节胺处理的棉花产量有增加的趋势。【结论】棉花化学打顶后通过叶片吸收药剂,封顶效应较慢,与人工打顶相比叶面积指数较高;由于对果枝长度控制,使株形紧凑,冠层开度增加,保证了冠层中、下部高的光吸收率,为棉花利用化学打顶控制株型提供了依据。

【Objective】In order to study the effect of chemical multi- topping agent on plant shape and canopy structural characteristics of cotton,we discussed chemical multi- topping agent adjusted plant type,the canopy structure and yield components of regulating effect,thus providing technical support for the application of chemical multi- topping technology application.【Method】Xinluzao 45 and 45- 21（ strains） were selected as the experimental materials,in the field of natural conditions,artificial multi- topping was regarded as control,to study the influence of chemical multi- topping agent for agronomic traits,canopy structure index and yield formation cotton.【Result】Compared to artificial multi- topping,the plant height,number of main stem section increased,plant width decreased,and plant type became tight; the leaf area index of different DIFN was higher than that of the artificial multi- topping,the canopy light absorption of different positions would be uniform,light absorption rate of middle and lower canopy were higher than those treated by artificial detopping; Different detopping agents showed the production of fluorine treatment had a tendency of increas-ing. 【Conclusion】The leaf area index of chemical detopping cotton was higher compared to artificial detopping,although cotton leaf absorb agent and its effect were slow; because the length of the branch was controlled,so plant type became compact,DIFN increased,and ensured the light of the high absorption rate of the middle and lower canopy. It provided gist for using chemical multi- topping control plant type in cotton.