Genetic association of geographic populations and species of lac insects of the genus Kerria (Hemiptera: Coccoidea) with EST-microsatellite markers

Lac insects belonging to the genus Kerria are commercially exploited for lac which has diversified industrial applications. India is the global leader in lac production; much of commercial lac is derived from the Indian lac insect, Kerria lacca (Kerr). Molecular marker studies of Kerria species are limited to RAPD and ISSR. We evaluated genetic diversity among 27 Kerria geographic populations belonging to thirteen species of Kerria, using 31 microsatellite markers developed from transcriptome of the Indian lac insect. The number of alleles per locus ranged between 2 and 6 with a mean of 2.74, showing polymorphism of 66.7-100%. UPGMA dendrogram based on Jaccard's similarity coefficient grouped 27 Kerria accessions into three major clusters consisting of 2, 13 and 12 populations respectively and their similarity coefficient ranged between 0.61 and 0.95. Based on similarity coefficients, the closest relationship was observed between Kerria pusana and Kerria pennyae and also between K. lacca and K. pennaye. K. chinensis appeared well separated from all other Kerria species studied. Geographically closer species were found more similar, in general. The present study reveals wide intra-and inter-specific genetic diversity among Kerria populations through EST-microsatellite markers and indicates the potential and usefulness of marker studies for lac insect improvement programmes.