蚕豆黄化卷叶病的药剂防治

喷药治蚜防病试验中,溴氰菊酯和久效磷对豆蚜(Aphis craccivora)的防效分别达到96.7%和67.1%。两次和三次施用溴氰菊酯的防病效果分别达到84.1%和86.1%,蚕豆产量分别比未施药对照增产17.7%和21.9%。施药也影响蚕豆黄化卷叶病的时间分布型,三次施药小区的病株始终为泊松分布,病害没有再次扩散;未施药小区早春病株就出现负二项分布,越冬前病害已经扩散。豆蚜蚜害率与蚕豆黄化卷叶病发病率密切相关。

CONTROL OF BEAN LEAF ROLL VIRUS IN BROAD BEAN WITH INSECTICIDES

The synthetic deltamethrin and monocrotophos provided 96.7% and67.1% control efficiency to Aphis craccivora.The variation in preventingbean leaf roll virus occured in different insecticides and sprayingtimes.Three times spraying deltamethrin in 4 November,24 March and28 April,or two times spraying deltamethrin in 4 November and 28April,provided 86.1% and 84.1% reduction of bean leaf roll virus,and 21.9% and 17.7% yield ncrease,respectively.Spraying insecti-cides affected the spatial distribution of infected plants.In the plots ofthree sprays,the Poisson distribution occured in all survey date.However,the fact that negative binomical distribution appeared in theuntreatment plots in the first survey in spring indicated that bean leafroll virus started to spread before winter.