Assessment of the damage and chemical and biological control of some cereal aphid species infesting wheat plants in Egypt

الملخص EN

This work aimed to assessment the damage caused by the infestation with some cereal aphid species on wheat plants at Sharkia Governorate during 2017/2018 season.

The results showed that the relationship between the yield of wheat plants and infestation of aphid was in negative correlation.

The damage economic threshold level for aphid was 29.57 individuals/100 plant tillers, the economic injury level was 36.28 individuals/ 100 plant tillers.

To assesse the efficacy of the tested insecticides against aphid under field conditions showed that chlorpyrifos was the most effective followed by thiamethoxam + abamectin and Beauveria bassiana.

The residual effects of the tested insecticides were 100, 86.67 and 79.73% for the previous tested insecticides, respectively.

The general effect of reduction percentages indicated 98.59, 69.75 and 79.73%, successively for the same tested insecticides in the first season (2016/2017).

While the residual effect showed 80.77 to Beauveria bassiana , 86.9 to thiamethoxam + abamectin and 100 to chlorpyrifos .On the other hand , the general effects in the second season (2017⁄2018) were Beauveria bassiana ( 80.77), thiamethoxam + abamectin (70.7) and chlorpyrifos ( 99.06 ).