The Role of Chrysoperla carnea (Steph.) and Beauveria bassina for Controlling Cabbage Aphid, Brevicoryne brassicae L. on Cabbage Plants

Saleh, A.A.A., H. El-Nagar, A.A. Khalifa and M.F.M. Zawrah. 2023. The Role of Chrysoperla carnea (Steph.) and Beauveria bassina for Controlling Cabbage Aphid, Brevicoryne brassicae L. on Cabbage Plants. Arab Journal of Plant Protection, 41(3): 321-326. https://doi.org/10.22268/AJPP-041.3.321326 Field experiments were carried out at Kafr Saqr district, Sharkia governorate during 2019/2020 and 2020/2021 growing seasons to evaluate the predator:prey ratios for the release of C. carnea and evaluation of using Beauveria bassiana suspension against the cabbage aphid, Brevicoryne brassicae. The results obtained showed that the effective control of B. brassicae was achieved ten days after releasing the larvae of the predator C. carnea when the predator:prey ratios were 1:5 and 1:10. Meanwhile, at higher ratios (1:20, 1:25 and 1:50), the cabbage aphid B. brassicae numbers decreased 25 days after predator release. The numbers of B. brassicae decreased by 84.69 and 81.61% at 1:5 and 1:10 predator:prey ratio during the first season, respectively. On the other hand, the aphid numbers were reduced by 81.50 and 70.95% at 5 days after the predator’s release during the second season, for the two predator:prey ratios, respectively. Complete reduction of B. brassicae populations was achieved at 15 days after yhe release of C. carnea larvae with predator ratios of 1:5, 1:10 and 1:15, and numbers of B. brassicae at these ratios depressed completely 20 days after release. The results revealed that the best control of B. brassicae populations under greenhouses conditions was achieved by using the lower predator:prey ratio of 1:5 and 1:10 ten days after releasing larvae of C. carnea. The highest mortality rate in B. brassicae population caused by the fungus B. bassiana was 88.33%, recorded at 7 days after the application of spore concentration 1×107 spores/ml and the LC50 obtained in the field was 1.10×106 spores/ml. It can be concluded from this study that C. Carnea and B. bassiana are effective biocontrol agents in controlling the cabbage aphid B. brassicae in the field. Keywords: B. brassicae, Chrysoperla carnea, Beauveria bassiana, Predator release.