湿度对球孢白僵菌和玫烟色虫草田间防治棉蚜效果的影响

本文以超低量喷雾的方式探究了在环境湿度调控下,球孢白僵菌Beauveria bassiana Bb202和玫烟色虫草Cordyceps(=Isaria)fumosorosea Ifu13a在不同应用剂量下对棉蚜Aphis gossypii的田间防效.结果表明,提高环境湿度可明显提高两种昆虫病原真菌对棉蚜的防效.在田间防...

Impact of Humidity on Field Control of the Cotton Aphid,Aphis gossypii by Beauveria bassiana and Cordyceps fumosorosea

In the present study, the field control of the cotton aphid Aphis gossypii by Beauveria bassiana Bb202 strain and Cordyceps (=Isaria) fumosorosea Ifu13a strain was investigated under humidity treatments by ultra-low-volume spray. The results showed that the control of A. gossypii by the two entomogenous fungi was significantly improved by increasing humidity. If humidity was increased by spraying water mist on the plants within two days post field application of the fungi, the control by B. bassiana Bb202 at 1.0×10⁷ and 1.0×10⁸ conidia/mL reached 64.24% and 75.96%, respectively, which was 24.60% and 32.21% higher than that under natural conditions, respectively. In the same way, the field control by C. fumosorosea Ifu13a at 1.0×10⁶, 1.0×10⁷ and 1.0×10⁸ conidia/mL was 50.00%, 84.63% and 85.45%, respectively, which was 22.77%, 38.28% and 22.54% higher than that under natural conditions, respectively. Both B. bassiana Bb202 and C. fumosorosea Ifu13a have good field control of A. gossypii, which can be significantly improved by increasing environmental humidity.