Exploring the Key Climatic Factors Driving the Outbreak of Tobacco Root-Knot Nematodes in Southwest China
Tobacco root-knot nematode is an important soil-borne disease caused by Meloidogyne spp.,which is distributed in major tobacco-growing areas in China,and can cause 30％～50％of yield loss in severe cases.Even more,the severity of root-knot nematode is increasing year by year.At present,there is relatively little research on the key factors affecting the occurrence of tobacco root-knot nematode disease,and the disaster mechanism of the disease needs further ex-ploration.By combining field investigation and laboratory analysis,this study determined the occurrence area and damage degree of tobacco root knot nematode disease in major tobacco-growing areas of Liangshan Prefecture,Sichuan Province in 2020.By morphological identifica-tion,Meloidogyne incognita was identified as the root knot nematode of tobacco collected from Liangshan Prefecture.Further comparative analysis of the average temperature and rainfall dur-ing 2010-2020 in Huili City showed that the average temperature from January to April in Tongan area,where tobacco root-knot nematodes occurred seriously,was higher than the his-torical value of the same period,with a temperature difference of 0.7～5.0 ℃,which was 2.8 ℃ higher on average.The cumulative rainfall from January to April in 2020 was more than 15％higher than the historical value,and the cumulative rainfall from May to August was more than 40％lower than the historical value.The results showed that higher temperature and more rain-fall before tobacco transplanting and less rainfall after transplanting were important effectors of the serious occurrence of tobacco root-node nematode disease in Liangshan Prefecture.The re-sults of this study provide a reference for monitoring and warning as well as timely prevention of root knot nematode disease.
万方数据
维普
