拔节期前后施用骠马对小麦光合作用的影响

Effect of the application of Puma before and after jointing on photosynthetic physiologies in the leaves of wheat

小麦是世界主要粮食作物之一,麦田杂草的危害是影响小麦生产发展的一个重要制约因素。试验采用随机区组设计,在小麦拔节前后每667 m2施用25、50、100、150、300 g的骠马除草剂,测定喷药后小麦叶片净光合速率(Pn)、气孔导度(Gs)、胞间CO2浓度(Ci)、蒸腾速率(Tr)等指标,旨在为在小麦田安全施用除草剂提供理论依据和技术支持。结果表明:拔节前、后喷施骠马,小麦挑旗期的倒二叶蒸腾速率随喷药剂量的增加呈下降趋势,而抽穗期和灌浆期呈先下降后上升的趋势。在挑旗期、倒二叶期水分利用效率呈上升趋势,抽穗期呈先上升后下降的趋势,而在灌浆期,倒二叶水分利用效率则呈下降趋势,说明随着骠马浓度的升高和小麦生育期的推后,小麦倒二叶水分利用效率逐渐降低,并且拔节后喷药水分利用效率明显低于拔节前喷药。

Wheat is one of main grain crop, the harm of weeds on wheat production development is one of the important factors. Trial used a randomized block design, before and after applying in wheat jointing 5 concentrations of herbicide Puma （25, 50, 100, 150, 300 g per 667 mz） after spraying, determination of wheat leaf net photosynthetic rate （Pn）, stomatal conductance （Gs）, intercellular C02 concentration （Ci）, transpiration rate （Tr） indicators, designed for safety application of herbicides in wheat field to provide the theory basis and the technical support. The results showed that： before spraying after jointing, Puma, in wheat flag leaf stage pour two leaf transpiration rate with spray dose increased decreased, while heading stage and grain filling period is decreased with rising trend. In flagging stage, fall two leaf water use efficiency rise, heading stage and then decreased, while in the period of grain filling, pour two leaf water use efficiency decreased, as the Puma concentration increases and wheat growth period after pushing two, the wheat leaf water use efficiency was reduced gradually, and after jointing stage spraying water use efficiency was significantly lower jointing the front spraying.