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对辣椒疫霉（PhytophthoracapsiciLeonian）在上海市郊蔬菜地土壤中的季节性变化和垂直分布进行了研究。结果表明，辣椒疫霉在一年中季节性的种群数量变化与温度的关系最密切，土壤中最多菌量出现的时间也是病原菌生长的最适温度（25～28℃）出现的时间，也正值该地的夏、秋季节。P．capsici在土壤中主要分布在地表10cm的土层中，10cm以下土层的菌量较少。当土壤中存有P．capsici的寄生植物时，P．capsici的数量比没有寄主时多，而且存活的时间也长，前者为18周，后者仅8周。无论是在湿润土壤中还是淹水的土壤中，由于孢子囊具有能抗不利环境条件的厚壁，故孢子囊存活时间均比游动孢子长。
The seasonal variation and vertical distribution of Phytophthora capsici Leoni in the soils of vegetables in the suburbs of Shanghai were studied. The results showed that seasonal change of population quantity and temperature of Phytophthora capsici in one year was the most closely related to the temperature. The time when the maximum amount of bacteria appeared in the soil was also the optimum time for pathogen growth (25-28 ℃) The value of the summer and autumn. P. Capsici is mainly distributed in the soil in the soil layer 10cm above the ground, less than 10cm soil layer. When there is P in the soil When the parasitic plants of capsici, P. The number of capsici was greater than when there was no host, and the survival time was also long, with the former being 18 weeks and the latter being only 8 weeks. Whether in wet or flooded soils, the sporangia live longer than the zoospores because the sporangia have thick walls that are resistant to adverse environmental conditions.