Abstract: The combining ability of seven Chinese silkworm parent materials and seven Japanese silkworm parents materials and their 49 cross combinations were analyzed in an 7×7 incomplete diallel crossing design for the following three omnibus quantitative characters which were larva-pupa survival rate, cocoon production per ten thousand silkworms,cocoon shell production per ten thousand silkworms. The results showed that Chunfeng and Ju 9 had higher general combining ability in 7 Chinese parents, the general combining ability of Zhen J and Hao J were higher in 7 Japanese parents. The special combination ability and the total combination ability of Zhen J×Ju 9,Hao J×Chunfeng, Xiangqiu×Ju 9, Hao J×Su 9 were higher, especially, Zhen J×Ju 9 was the highest. These combinations can be used as target combinations, strengthen parental material selection at the same time. The properties of cocoon and silk of these target combinations were studied comprehensively. It is expected to breed varieties that meet the breeding objectives.

Key words: parent materiasl of silkworm, comprehensive quantitative character, combining ability, incomplete diallel crossing design