摘要
本文对桑蓟马种群时、空动态及危害指标进行了研究。结果表明:桑蓟马在田间呈聚集分布,虫口密度持续增长,高峰虫量叶随叶位上升而上升,具显著的分层危害特点。在此基础上讨论了该虫的抽样技术,给出了理论抽样公式和防治阈值确定上序贯抽样的应用实例。首次提出了危害指数的概念和计算公式并进行了初步验证。
The timely and spatial dynamic states of mulberry thrips population and the relationship be-tween thrips density and leaf symptom were studied in this paper. The results showed that the dis-tribution of thrips population in the mulberry field appeared aggregated; its population density in-creased continously with time and thrips kept concentrating on leaves on upper part of the shootsduring the whole growing seasons. Based on the established Iwao regression equation (M=5. 23+1. 01?), the theorical sampling formula of thrips as well as an example of applying sequentialsampling technique in the determination of its control threshold value were provided. In addition,a harmfulness index--Q value was recommended and preliminarily examined for the first time.
出处
《安徽农业大学学报》
CAS
CSCD
1993年第1期72-78,共7页
Journal of Anhui Agricultural University
关键词
桑蓟马
种群动态
危害指数
桑树
Mulborry thrips
Population dynamic state
Sampling technique
Harmfulness index
