【目的】 研究共生菌Arsenophonus、水稻和温度对褐飞虱黄绿绿僵菌发病率的影响,揭示影响褐飞虱黄绿绿僵菌发病的重要因子。【方法】 通过共生菌Arsenophonus（感染和未感染）与水稻品种（TN1、IR56和Mudgo）以及Arsenophonus与温度（21℃、23℃、25℃、27℃、29℃和31℃）两个二因素完全随机区组试验,观察喷黄绿绿僵菌孢子悬浮液后不同时间褐飞虱黄绿绿僵菌的发病率。【结果】 喷黄绿绿僵菌孢子悬浮液后,不同水稻品种上褐飞虱发病率均以含Arsenophonus的试虫较低,而不同温度下的褐飞虱发病率则仅喷菌处理后第3 d和5 d时在25℃、27℃和29℃时含Arsenophonus的试虫发病率显著较低,其他温度下无显著差异。双因素方差结果表明,Arsenophonus与水稻品种双因素试验中均以含Arsenophonus褐飞虱黄绿绿僵菌的发病率显著较低,而Arsenophonus与温度双因素试验中仅在喷菌处理后第3 d、5 d以含Arsenophonus褐飞虱黄绿绿僵菌的发病率显著较低。温度显著影响褐飞虱的发病率,23℃~29℃条件下褐飞虱的发病率较高,LT₅₀较短,为黄绿绿僵菌侵染褐飞虱的适温范围。其中,27℃时发病率最高,LT₅₀最短,最为适宜;31℃和21℃条件下褐飞虱发病率较低,LT₅₀较长,不利于黄绿绿僵菌对褐飞虱的侵染。温度还影响含Arsenophonus与不含Arsenophonus试虫LT₅₀的相对大小。其中,含Arsenophonus试虫LT₅₀在27℃、29℃时相对较长,在其他温度下则相同甚至较短。【结论】 共生菌Arsenophonus显著抑制黄绿绿僵菌对褐飞虱的致病力,且该作用受到温度的显著影响;温度亦显著影响褐飞虱的黄绿绿僵菌发病率,而水稻品种以及Arsenophonus和水稻品种间、Arsenophonus和环境温度间的交互作用均无显著影响。

【Objective】 To reveal the significant factors affecting the incidence rate of the brown planthopper (BPH) to Metarhizium flavoviride, laboratory bioassays were carried out to study the influence of symbiotic bacteria Arsenophonus, rice variety and temperature on the incidence rate of BPHs to M. flavoviride. 【Method】 Through two completely randomized block trial: 1) symbiotic bacteria Arsenophonus (infected and uninfected) versus rice varieties (TN1, IR56 and Mudgo), 2) and Arsenophonus (infected and uninfected) versus temperatures (21°C, 23°C, 25°C, 27°C, 29°C and 31°C), BPHs with symptoms of M. flavoviride infection were observed after exposure to the spore suspensions of M. flavoviride for different periods. 【Result】 For all tested rice varieties, the incidence rates of M. flavoviride-treated BPHs infected with Arsenophonus (BPH++) were lower than that of BPHs uninfected (BPH--). Out of tested temperatures, only under 25°C, 27°C, 29°C, BPH++ has lower incidence rates than BPH-- at 3 d and 5 d after spraying. However, there was no significant difference among others. The results of two-way ANOVA analysis between Arsenophonus and rice varieties also indicated that the incidence rate of BPH++ was lower than that of BPH--. Furthermore, two-way ANOVA results between Arsenophonus and temperatures indicated the incidence rate of BPH++ was lower than that of BPH-- at 3 d and 5 d after spraying. The effect of temperature was significant on the virulence of M. flavoviride to BPHs. BPHs had higher corrected incidence rates and shorter LT₅₀ under 23°C–29°C than that under 21°C or 31°C. Out of these BPHs, the highest corrected incidence rates and shortest LT₅₀ were found at 27°C. It suggested 23°C–29°C was suitable temperature for infection of M. flavoviride, among which 27°C was the best. This suggested that low or high temperatures would negatively affect the virulence of M. flavoviride to BPH. The temperature also affected the LT₅₀ of BPHs. The LT₅₀ of BPH++ was longer than that of BPH-- under 27°C or 29°C. However, the LT₅₀ of BPH++ was equal or even shorter than that of BPH-- under other temperatures.【Conclusion】 Arsenophonus decreased the virulence of M. flavoviride to BPH, which was influenced by temperature. The temperature also affects the incidence rate of BPHs to Metarhizium flavoviride significantly. However, the effects of rice varieties and interactions of Arsenophonus and rice varieties and Arsenophonus and temperatures were not significant on the incidence rate.