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Abstract：
The objective of this work was to evaluate the development of Davidiella sp. and its asexual form, Cladosporium sp., under different environmental conditions in the rubber tree (Hevea brasiliensis). Rubber tree leaves were inoculated with a spore suspension and kept in a humid chamber under different temperatures and wetness periods. The behavior of the fungi was evaluated using a scanning electron microscope (SEM) and an ultraviolet light microscope (UV). In the images obtained in SEM, four hours after inoculation of the fungus, it was possible to verify the germination and penetration of conidia at temperatures of 10 to 20 °C. The formation of conidiophores was verified from six hours after inoculation, indicating that it is in the reproductive period. In the sexual phase, in SEM, from four hours after inoculation, it was possible to verify the formation of small protuberances at temperatures between 10 and 20 °C. These black dots evolve into circular, protruding black spots, like the symptoms of black crust, with apparent spore formation on them. The data obtained from the UV analyses corroborate those from SEM, showing that the fungus has good development in its two phases between temperatures of 20 and 25 °C and that the period of wetness on the leaf can contribute to the initial development of the pathogen.
摘要：
这项工作的目的是评估Davidiellasp。的发展。和它的无性形式，枝孢霉sp.,在橡胶树（巴西橡胶树）的不同环境条件下。用孢子悬浮液接种橡胶树叶，并在不同的温度和湿润时间下保存在潮湿的室内。使用扫描电子显微镜（SEM）和紫外线显微镜（UV）评估真菌的行为。在SEM中获得的图像中，接种真菌四小时后，可以在10至20°C的温度下验证分生孢子的发芽和渗透。从接种后六小时开始验证分生孢子的形成，表明它处于生育期。在性阶段，在SEM中，从接种后四小时开始，可以在10至20°C之间的温度下验证小突起的形成。这些黑点演变成圆形，突出的黑点，比如黑皮的症状，上面有明显的孢子形成。从紫外线分析获得的数据证实了SEM的数据，表明该真菌在20和25°C的温度之间的两个阶段都具有良好的发育，并且叶片上的湿润期可以促进病原体的初始发育。
