Comparative Characteristics of Bivoltine Silkworm Hybrids

Abstract

Comparative characteristics of bivoltine silkworm hybrids were conducted at Chiang Mai Sericultural Experiment Station. The diallel crosses among PH2, PH3, PH5, PH8, PH9 and PH10 were randomly allocated into 30 treatments. The treatments were then assigned in the randomized complete block design with 3 replications. Three continued experiments of the hybrids were conducted; the first period during June-July 1996, the second period during September-October 1996 and the third period during January-February 1997. The PH5 x PH10 and PH9 x PH5 hybrids were consistently produced more vigorous larvae and yielded better cocoon qualities in all three conducted experiment periods; they provided high percentage of good cocoons, high weight of single cocoon and single cocoon shell, and high percentage of cocoon shell. The hybrids exhibited good charecteristics only occurred in two experiment periods were PH2 x PH5, PH3 x PH5, PH3 x PH8, PH3 x PH9, PH3 xPH10, PH5 x PH3, PH5 x PH9, PH8 x PH5, PH9 x PH2, PH9 x PH3 and PH10 x PH9, however, there were no significantly difference among these hybrids.