1965 Volume 16 Issue 4 Pages 282-287
Crossing experiments were carried out between Gr and Ka strains of Culex pipiens s. l. with different genetical characters, the former representing autogenous or molestus-form associated with greencoloured larval mutants, and the latter being anautogenous pallens-form with normally coloured larvae. F_1 eggs obtained by the crossing between Ka-females and Gr-males showed only 1.8% of hatching rate, the rest 53.1% harboured embryos which were matured but unhatched, and 45.1% were unfertilized. The above rates for F_1 eggs of the cross between Gr-females were 0.1%, 36.8%, and 63.1% respectively. The sex ratio of the former cross was roughly 1 : 1 but all the adults recovered by the latter were females. The hatching rate of F_1 hybrids of the former was almost as high as that of the parent colonies. Gr was selected from a colony of molestus n nature and has been established as a homozygous green larval strain. In the former crosses phenotype of F_1 larval were all "green". Larvae of F_2 were composed of 20.6% of green, 19.6% of normal and 60.4% of intermediate. It was estimated from the above results that the green character is polyfactorial in its inheritance. Among the females obtained by the former crosses, the autogeny rate was 6.7% at F_1 and 3.8% at F_2. No correlation was observed between the apearances of larval colour types and the autogeny of the females.
