橡胶树炭疽病流行规律研究

大田系统观察结果表明，橡胶树炭疽病发病过程有越冬，始发，流行和病情下降４个阶段，流行方式有暴发型和渐发型２种，流行曲线有多峰波浪型和单峰弓型，流行规律的研究结果表明，该病发生流行与菌量，物候，气候，品系，菌株和立地环境等有关，菌量和易感病组织是病害流行的基本条件，多雨高湿是病害流行的主导因素，不同地区的菌株致病性不同，在小区内相同条件下不同橡胶品系抗病性也不同。通过流行规律研究，提出该病的喷经防治

Epidemic Process of Anthracnose of Hevea Brasiliensis

Observation of the epidemic process of anthracnose(Collectotrichum gloeosporioides)of rubber trees (Hevea brasiliensis) revealed that the epidemic of this disease includedfour stages: wintering,onset,outbreak and decline. There existed two epidemic patterns,sudden and gradual. There were two types of epidemic curve:a wavy line with several peakswhich appeared in outbreaking years and a bowed line with one peak in the years withlight disease. Analysis of the factors affecting the epidemic disclosed that the epidemicwas associated with such factors as amount of inoculum,phenophase of rubber trees,weather,clones of rubber trees,isolates of pathogen and the microclimate of the plantations. Inoculum and susceptible tissues were the basic conditions for the epidemic,whereas rainfall and humidity were the prevai1inS factors invoking occurrence of the epidemic.The pathogenicity of the isolates varied in different plantations,and clonal resistance varied under the same conditions of the plots as well. An index for spray controlling the epidemic was recommended based on the epidemic process.