重庆地区天竺桂煤污病与日本壶链蚧发生的关系研究

Study on the Relationship Between Asterococcus muratae Kuwana and Sooty Blotch and Flyspeck of Cinnamomum japonicum Sieb in Chongqing

为明确重庆地区天竺桂煤污病分级,并研究煤污病与日本壶链蚧发生的关系,本文采用单位叶面积煤污层称质量的方式建立煤污病分级标准,利用Pearson和Spearman相关性分析对煤污病病情指数随日本壶链蚧发生量变化的关系进行研究.结果表明,以单位叶面积煤污层称质量的方式可较好地反应植物叶片煤污病发生严重程度;相关性研究显示,煤污病病情指数与日本壶链蚧发生量呈对数关系,拟合的公式为y=0.0909 ln(x)+0.2411,决定系数R 2为0.8023.表明初期煤污病病情随着日本壶链蚧发生而快速增长,当日本壶链蚧发生达到一定数量后,病情增长速度放缓或停止增长.该结果为预测天竺桂煤污病发生,指导生产一线开展防控工作具有重要意义.

In order to clarify the classification standards of sooty blotch and flyspeck(SBAF)of Cinnamomum japonicum Sieb.in Chongqing,and to study the correlation between SBAF and the occurrence of Asterococcus muratae Kuwana,a classification standard of SBAF is established in this paper with the method of weighing the SBAF layer per leaf area,and Pearson and Spearman correlation analysis is used to study the relationship between the disease index and the occurrence of A.muratae.The results indicate that the weighting method can satisfactorily reflect the severity of SBAF.Correlation studies show that disease index is in a logarithmic relationship with the occurrence of A.murataea,the fitted formula being y=0.0909 ln(x)+0.2411 and the coefficient of determination R 2 being 0.8023,thus suggesting that at the initial stage,SBAF will rapidly increase with the occurrence of A.muratae,and when the occurrence of A.muratae reaches a certain level,the growth rate of the disease slows down or stops growing.This result is of great significance for predicting the occurrence of C.japonicum Sieb.SBAF and guiding the front-line prevention and control work.