DOI: 10.22620/agrisci.2011.06.022
Abstract
Bulgaria has the richest silkworm, Bombyx mori L. genetic resources in Europe. Two hundred and twenty-six silkworm strains, originating from 16 different countries are included in the germplasm. Different methods have been implemented in the silkworm selection such as: segregation and separation from foreign F1 hybrids; using pure and creating initial hybrid populations for further breeding; creation of sex-marked breeds in the egg-, larva- and cocoon-stage; breeding of strains tolerant to adverse rearing conditions by using a tropical polyvoltine breed and testing them under a provocative regime; using gamma rays, laser rays and different temperatures for modifying the different phenotype character expression and heterosis in schemes for creation of highly productive hybrid populations for breeding of new lines and hybrids; breeding for movement behaviour of the larvae, by parthenoclones and androgenetic lines. Considering the comparatively rich silkworm genetic resources, an International Regional Center could be established in Bulgaria with the aim of collecting, preserving and improving the germplasm, exchanging and providing genetic material, as well as training of experts in silkworm genetics and breeding.