Inheritance of fenvalerate and carbofuran resistance in colorado beetles-Leptinotarsa decemlineata (Say)-from North Carolina

Progeny from reciprocal F1 crosses and F1 backcrosses between fenvalerate‐resistant and fenvalerate‐susceptible Colorado beetles, Leptinotarsa decemlineata (Say), and between carbofuran‐resistant and carbofuran‐susceptible Colorado beetles were bioassayed to investigate the mode of inheritance of resistance to these chemicals. Bioassays of progeny from these crosses indicate that resistance to fenvalerate is inherited in a semi‐recessive, sex‐linked manner and carbofuran resistance is inherited in a partially dominant autosomal fashion. Log concentration/probit mortality lines and chi‐square tests, however, indicate that multiple genes may be involved in resistance to both insecticides.