Study on the possibilities for creation of new silkworm, Bombyx mori L. hybrids with high tolerance towards unfavorable larval rearing conditions by crossing sex-limited for larval markings with hardy silkworm breeds

Panomir Tzenov, Krasimira Avramova, Dimitar Grekov

Abstract: The present study aimed to investigate the possibilities for creation of new, tolerant to adverse rearing conditions four-way silkworm hybrids by crossing sex-limited for larval markings with hardy silkworm breeds. The main goal expected of the new hybrids would be an easier and more precise egg production, combined with a higher viability and productivity under adverse rearing conditions, which is the common practice at the field level. By means of crossing between sex-limited for larval markings silkworm breeds and breeds possessing high sturdiness there were created and tested two new silkworm hybrids. In the conditions of a provocative silkworm rearing regime, they showed considerably high silkworm vitality (HB2xNova2 81.17%), which exceeded that of the control (Super 1 х Hesa 2 – 50.50%), having average and high values of cocoon weight and silk shell weight, as well as high silk filament technological character values at the optimal rearing conditions.

Keywords: Bombyx mori L; crossing; sex-limited breeds; sturdiness

Date published: 2022-11-02