Molecular Analysis of Divergence in Tachinid Uzi (Exorista Sorbillans) Populations in India
Source: Genetica, Volume 125, Number 1, September 2005 , pp. 1-15(15)
Abstract:Exorista Sorbillans is a tachinid endoparasitoid of silkworm, Bombyx mori, and is globally known as uzi. It causes economic injury to the cocoon crop in silkworm cultivating areas of India, except those above 400 m above mean sea level (AMSL) in the foothills of the Himalayas (Darjeeling). It is reported that the sericulture tract of south India became infected with this pest only since 1980 through an accidental transportation of cocoons from West Bengal. To ascertain whether the genome of this parasitoid is differentiating into discrete gene pools in contrasting geo-climatic conditions, molecular profiling of four populations (Es Annatapur, EsRamanagaram, Es Channapatna and EsKodathi from south India and EsMurshidabad from Murshidabad, West Bengal was undertaken with 13 ISSR, 3 RAPD and six non-random primers designed from various repeat sequences of B. mori . MANOVA indicated significance for the Roy’s largest root estimate (55.4; F =18.47; p = 0.002) for the variability contributed by the replication. Further, hierarchical clustering done on the basis of Euclidean distance matrix and Nei’s unbiased Phylip clustering put EsMurshidabad at the maximum distance from those of south India and 29 markers could also be identified which significantly differentiateEsMurshidabad from others. However, Nei’s statistics for gene diversity in sub-populations reveal considerably high gene-flow (3.44 and 2.51) among the populations around Bangalore. The gene-flow between EsMurshidabad and other population is lowest but cannot be ignored. The comparison of endosymbiont specific 16SrRNA and fts Z gene (partial) sequences through clustalW (gcgMSF) revealed a closer relationship of EsMurshidabad withEsAnnatapurand Es Ramanagaram and is not congruent with the relationships discussed above. The significance of this maiden study with a tachinid fly-pest is discussed in the context of understanding the diversification of Uzi fly-pest and also establishing this pest as a relevant biological material for studying microevolution in future.
Document Type: Research Article
Affiliations: 1: SeriBiotech Laboratory, Central Silk Board, Kodathi Campus, Sarjapur Road, Carmelram, 560035, Bangalore, Karnataka, India, Email: firstname.lastname@example.org; email@example.com 2: SeriBiotech Laboratory, Central Silk Board, Kodathi Campus, Sarjapur Road, Carmelram, 560035, Bangalore, Karnataka, India,
Publication date: September 1, 2005