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应用诱饵分离技术对上海地区两个自然发病土壤中樟疫霉（Phytophthoracinnamomi）的密度进行了为期25个月的测定．结果表明．樟疫霉在两个不同寄主土壤中呈季节性规律变化，夏、秋季最高，其带菌土样率和回收菌株数分别高达44％和83株；冬季最低，在土壤中检测不到．春季开始回升．该菌密度与某些生态因子的回归分析结果表明．它主要与土壤温度呈显著相关（P＜0.05）．最适土温25℃左右．小于10℃时检测不到。该菌密度在土壤中的季节变化与寄生植物病害的发生存在着内在联系．该菌密度越高，寄主病害越重。此外．本文还就以诱饵法作为检测分析土壤中土传病原菌生态变化的一种有效途径作了探讨。
The density of Phytophthora cinnamomi in two naturally occurring soils in Shanghai area was measured for 25 months using bait separation technique. The results show. The P. camphorata had seasonal changes in two different host soils, the highest in summer and autumn, with the highest rates of bacterial-carrying and recovering strains of 44% and 83 strains, respectively. The lowest in winter and no in soil. Spring starts to pick up. The density of bacteria and some ecological factors regression analysis results show. It is mainly correlated with soil temperature (P <0.05). The optimum soil temperature about 25 ℃. Less than 10 ℃ undetectable. The density of the bacteria in the soil seasonal changes and the occurrence of parasitic plant diseases are intrinsically linked. The higher the density of the bacteria, the heavier the host disease. In addition. In this paper, bait method is also used as an effective way to detect and analyze the ecological changes of soil-borne pathogenic bacteria in soil.