Effect of Pest Control Applications on Sorghum-Panicle Pests and Associated Predators at Sohag Governorate, Egypt

Abstract

Sorghum panicles offer a very rich microenvironment for many insect pest species and their natural enemies. A field experiment was conducted on sorghum (Sorghum bicolor L.) variety "Shandaweel 6" in Shandaweel Research Station (SRS), Sohag Governorate, Egypt during the 2019 growing season. Lepidopteran and hemipteran pests were the most dominant species-infested sorghum panicles during the half bloom stage of the panicles. Three microlepidopteran pests, the noctuid, Eublemma gayneri (Roth.); the pyralid, Cryptoblabes gnidiella Millière, and the cosmopterigid, Pyroderces simplex Walsingham, were recorded as major pest species infesting sorghum panicles in Sohag Governorate. Four treatments; B. bassiana, Bt, Thuja extract and Lambada-cybalothrin pesticide were applied against sorghum panicle pests in general, and particularly against the mention microlepidopteran pests. Pesticide was recorded the highest reduction rates in the target pests (E. gayneri, C. gnidiella and P. simplex) with 68.48, 78.46, 80.41 and 81.55% respectively, these effects were significantly differed with the rest of the compounds except thuja extract against C. gnidiella, where the differences between the chemical pesticide and B. bassiana faded. also, in the non-target pests, pesticide was recorded the highest reduction rate of Aphid, Thrips and Hemipteran pests with 67.98, 75.95 and 57.11% respectively, and significant difference with the rest of the compounds was noted except B. bassiana in the case of Aphid and Hemipteran pests, where the differences between the chemical pesticide and B. bassiana faded.