马蹄金白绢病发生规律及化学防治技术的研究

采用系统调查方法和室内外防治试验法对马蹄金白绢病进行研究,结果表明,8月上旬-9月上中旬是马蹄金白绢病发病的高峰期.9月中下旬以后,随着温度的降低,病情指数缓慢下降.通过主成分分析,把6个气象因子转化为3个综合因子,且反映原来因子的信息,彼此之间互不相关.建立了发病普遍率与病情严重度之间的定量关系.4种常用杀菌剂对马蹄金白绢病菌的菌丝均有不同程度的抑制作用,其中代森锰锌毒力最强,防治效果最优.用9种聚集度指数的方法测定了,马蹄金白绢病在草坪间的分布型,结果表明,均呈聚集分布,其分布的基本成分为疏松个体群,数量为2400株,抽样以8～13点为宜.

Study on the control technique and regularity of outbreak of southern sclerotion blight of creeping Dichondra repens

Systematic investigation method,interior and outside control test were applied in order to scientically sample and effectively control southern sclerotion blight of creeping Dichondra repens.The result showed that there was a fastigium from the first ten days of August to the first and the middle ten days of September.After the middle and the last ten days of September,the disease index fell tardily with a decrease in temperature.This disease was a high temperature and high humidity plant disease,through application of principle component analysis,it changed six meteorologic factors into three integrated factors and reflected information of intrinsic factors which were not concerned with each other.what's more,it established the quantitative relation between the disease incidence and the disease index.Four kinds of common fungicides in this experiment have different inhibitory effects to the hyphae of creeping D.repens,and the toxicity of Mancozeb was remarkable and the control effect of 75% Mancozeb on southern sclerotium blight of creeping D.repens was the best with 45 milligrams per square meters.The distribution of population of creeping D.repens was determined with nine aggregate indexes.The results showed that all were aggregate distribution,and their fundamental component of distributions were loose individuals,and the numbers of these were 2 400.At the same time,it was suitable to take spots from 8 to 13 for sampling.