| Through the investigation of oil palm disease in Haikou, Danzhou, Wenchang, Lingshui, Ding爷an and Guangdong Jiangmen, it showed that the most common disease was leaf spot, and different varieties suffering this disease performed differently; when serious, it could lead to more than 30% exsciccation of leaves. In this paper, the field severities of leaf spot of 12 kinds oil palm were investigated in Jiangmen Guangdong, which showed that most cultures爷rating was 1-3 index. The pathogen was isolated and purificated, and there were 6 kinds of pathogens, such as Colletotrichum sp., Alternaria sp., Phyllosticta sp., Phomopsis sp., Phoma sp. and Pestalotiopsis sp., respectively. The tests of pathogenicity found that symptoms similar to the originalones appeared after 7 days, while the control plants remained healthy, and the pathogen was reisolated from the leaves of inoculated plants, and the pathogenicities of Colletotrichum sp. and Alternaria sp. were weak, speculating that it might be saprophytic fungus. Other four fungus could infect RYL31, while Phyllosticta sp. Could infect RYL14 and RYL33, speculating that this disease pathogen had a stronge parasitism. |
