Abstract: F1 hybrid with improved economical character and cocoon color has been bred by crossing colored cocoon silkworm to white cocoon silkworm which is different in economical char-acter from colored cocoon silkworm. The average fibre size of F1 hybrid is 3. 23 D and its whole cocoon weight and the percentage of cocoon shell weight increases by 71. 32 % and 29.71 % re-spectively over that of the F0. The other characters meet the demand of raue cocoon silk.

Key words: Silkworm, Colored cocoon, Economical character

CLC Number: 

• S886.2