Genetic basis and realized heritability of laboratory selected spirotetramat resistance for insecticide resistance management in Oxycarenus hyalinipennis Costa (Hemiptera: Lygaeidae)

Dusky cotton bug, Oxycarenus hyalinipennis Costa (Hemiptera: Lygaeidae) is become a major pest of cotton. It causes damage to cotton by sucking the cell sap or by staining the cotton seed. Insect pests in Pakistan are mainly managed by use of insecticides, applying this practice leads to resistance development. In this study, O. hyalinipennis was selected with spirotetramat under laboratory conditions to investigate genetic mode of resistance to spirotetramat. Selection with spirotetramat for eleven generations resulted in a 727-fold resistance compared to the susceptible strain. The LC₅₀ values of spirotetramat in both reciprocal crosses were significantly different from each other and degree of dominanace values were 0.25 for cross-1 and 0.01 for cross-2. Monogenic model proved the contribution of more than one gene in controlling the spirotetramat resistance. Moreover, the value for realized heritability of spirotetramat resistance was 0.13. It can be concluded that spirotetramat resistance was sex linked, polygenic and incompletely dominant. These findings could be helpful in management of spirotetramat resistance in O. hyalinipennis as incompletely dominant and polygenic resistance tend to develop slowly and is manageable.