Hybridization schemes for developing new silkworm (Bombyx mori L.) races by using populations from different ecogeographical zones

Abstract

Different hybridization schemes with populations from various ecogeographical zones were studied with a view to developing new silk worm races. Hybrid populations of Japanese and Chinese types were bred by using the following methods: Simple crossing (A x B}, Complex crossing ((A x B) x C and (A x B) x (C x D)] and Backcrossing.

It was established that the efficiency of silkworm breeding programmes is determined not only by the hybridization methods and schemes, but also by the ecogeographical determinism. of the source populations used. Therefore, the inclusion of populations with different ecogeographical origins into the silkworm breeding programmes would lead to improvement of the most important economic traits, determining cocoon- and raw silk productivity, instead of increasing the genetic potential of the source material
used.