环境因子对努利虫疠霉产孢和孢子萌发的影响

Environmental factors affecting sporulation and germination of Pandora nouryi.

探讨努利虫疠霉Pandora nouryi（Remaudière＆Hennebert）Hümber在田间蚜虫种群中发生与流行的规律，研究外界环境因子对感菌虫尸产孢和孢子萌发的影响。结果表明，处于水琼脂培养平板上感染努利虫疠霉的桃蚜虫尸在8-25℃的温度范围内均能产生大量的初生分生孢子，在30℃下，仅弹射极少量孢子。8℃下，孢子弹射可以持续120h，当温度高于15℃，大部分的孢子会在48h内完成弹射。相对湿度小于95％，虫尸停止产孢。20℃下，光照条件不会影响虫尸弹射孢子的总量。在8℃和30℃时，24h后处于水琼脂培养平板上的孢子萌发率分别为45．23％和61．74％，显著低于15—25℃温度范围内的孢子萌发率（95％以上）。处于叶片上的真菌孢子，当相对湿度大于74％时出现萌发，但在盖玻片的表面，当湿度低于100％时未发现孢子萌发。

For further understanding of development of Pandora nouryi （ Remaudière ＆ Hennebert） Hümber in aphid populations in field, the effects of environmental factors on spomlation from cadavers of Myzus persicae and conidial germination were studied. P. nouryi discharged large numbers of primary conidia over the range 8 - 25℃ from cadavers on the surface of water - agar. At 8℃ conidial discharge lasted for 120 hours, but most conidia were produced within 48 hours when temperature was 〉 15℃. Saturated humidity alone was not enough to allow for spondation to occur freely and where RH 〈 95 %, no conidia were discharged. Light did not affect the pattern of conidial production nor the total number of conidia. Germination percentages of conidia on the surface of water - agar were40.50% and 66.51% at 8℃ and 30℃ respectively, which were significantly lower than that at 15 - 25℃ where germination was 〉 95 %. Conidia on leaves could germinate well when RH 〉 74 %, while no germination occurred when RH 〈 100% on cover slips.