Abstract
Two Thai multivoltine silkworms, Bombyx mori L., Nang-noi and Kotung strains and Japanese mulberry wild silkworm, Bombyx mandarina Moore were reared with fresh mulberry shoots at 25 ℃ in rearing room until measurement for cocoon weight, shell weight. Hybrid silkworm eggs were prepared from the Thai multivoltine female moths and male wild silkworm. The F1 hybrid eggs between B. mori and B. mandarina silkworms were reared with mulberry shoots. Larval duration from hatching to maturing was only 10 days which is referred as trimolter. Cocoon weight, shell weight, percentage of shell weight were superior to parental breeds. Cocoon shape was similar to that of Thai multivoltine strains, but showed in light green color instead of yellow. Fiber length, fiber weight, filament size (denier) were 406.8 ± 0.19 meters, 6.70 ± 0.11 centigrams and 1.68 ± 0.16 denier, respectively.
