Biodiv Sci ›› 2013, Vol. 21 ›› Issue (3): 315-325.DOI: 10.3724/SP.J.1003.2013.11035

• Orginal Article • Previous Articles     Next Articles

Genetic diversity and molecular genealogy of local silkworm varieties

Zhouhe Du1,2, Junfeng Liu1,*, Binbin Liu1, Yanchun Zuo1, Jianmei Wu1, Yi-an Chen1, Jianfei Zhang1, Cheng Lu2,*()   

  1. 1 Institute of Sericulture, Sichuan Academy of Agricultural Sciences, Nanchong, Sichuan 637000
    2 Institute of Sericulture and Systems Biology, Southwest University, Chongqing 400716
  • Received:2013-02-04 Accepted:2013-04-26 Online:2013-05-20 Published:2013-06-05
  • Contact: Liu Junfeng,Lu Cheng

Abstract:

In order to explore the genetic diversity and systematic differentiation pattern among silkworm varieties, aiming to guide hybridization breeding, we sequenced a total of 72 Bmamy2gene fragments from local silkworm varieties. The analysis of nucleotide sequence diversity and systematic differentiation indicated that there was rich genovariation in the sequencing region of Bmamy2gene, and the base mutation rate is 5.6- 8.2%, the haplotype diversity is 0.8294, and the nucleotide diversity is 0.0236±0.00122, suggesting Bmamy2being a better marking gene with rich nucleotide sequence diversity, based on which the genetic diversity among different local silkworm varieties can be identified. The same heredity population structure is proclaimed by several analysis methods that every clade consisting of varieties from different geosystems and ecological types, while the varieties from the same geosystem and ecotype belong to different clades in the phylogeny. There is no population structure pattern that different varieties claded together according to geosystem or ecotype. It can be speculated that the silkworm origins from mixture of kinds of several voltinism mulberry silkworm, Bombyx mandarina, while the domestication events took place in several regions, from which the domesticated mulberry silkworms are all devoting to the domesticated silkworm population of today.

Key words: Bombyx mori, germplasm resources, genetic diversity, molecule genealogy