Assessment of Combine Ability of Perspective Bulgarian and Romanian Silkworm Bombyx Mori L. Races.
I. On the Basis of Diallel Crosses

N. PETKOV1, Y. NATCHEVA1, Y. VASILEVA1, Z. PETKOV1, E. MATEI2, E. PAU2, D. DOGARU2 and M. CIULU2
1Regional center for Scientific-Applied Service, BG -3000 Vratza, Bulgaria
2 Commercial Society "Sericarom S.A.", 78431 Bucurest, Romania

Abstract

PETKOV, N., Y. NATCHEVA, Y. VASILEVA, Z. PETKOV, E. MATEI, E. PAU, D. DOGARU, M. CIULU, 2005. Assessment of combine ability of perspective Bulgarian and Romanian silkworm Bombyx mori L. races. I. On the basis of diallel crosses. Bulg. J. Agric. Sci., 11: 747-753

General combine ability (GCA) and specific combine ability (SCA) of eight perspective Bulgarian, four Romanian silkworm races and initial forms of introduced in a mass into practice super1 x Hessa 2 and Vratza35 x Mereffa2 hybrids were tested. Second model for accidentally chosen inter races combinations (Griffing, 1956) was used in our study. It was determined that GCA was not in relation with SCA manifested in races, used as components for hybridization.
The highest GCA was determined in Vratza63, Vratza65, Vratza64 and Vratza2012 races for cocoon weight and in Alba Cislau, Vrazta2003, ÒÂ/7, Vrazta2012 for shell ratio character. Baneasa21, T-15/4, Vratza35, Vratza65 and Vratza2012 races had comparatively high SCA in relation to cocoon weight character and Vratza63, Alba Cislau, Vratza2003, super1, T-15/4, Vratza64, Mereffa2 and Vratza2012 in connection to shell ratio character.
We recommend combination between mentioned above Bulgarian and Romanian races with equal type (larval marking and cocoon shape) to be used for creation of new selection hybrid combination, and combination between different types to be used for new hybrid creation.

Key words: silkworm, combine ability, hybrid, diallel crosses, cocoon, shell ratio