effect of long term egg preservation on morphological, reproductive and molecular characters of silkworm (bombyx moril.)mutant genetic stocks

Research Article
Muthulakshmi M and Kamble CK
Mutant Silkworm Bombyx mori, Longterm Preservation, Reproductive, Morphological, Molecular Traits

Studies on long term egg preservation schedule from 180 days to 300 days was taken up with 20 germplasm accessions of mutant silkworm genetic stocks of Bombyx mori L. to reduce the cost of conservation and minimize the genetic erosion leading to reduced crop cycle. Phenotypic stability was confirmed qualitatively by morphological characterization and quantitatively by growth and reproductive traits. To confirm the genetic stability molecular markers viz; SSR (simple sequence repeat) markers were used. It was found negligible polymorphism existed between control and treatment batches. The overall genetic similarity ranged from 0.9 to 1 in the selected mutant silkworm genetic stocks. Without genetic divergence in all the twenty silkworm races, the control and treatment batches aligned together. Since the longterm preservation in mutant silkworm genetic stocks did not alter their phenotypic and genetic stability, it is quite possible to reduce the number of crop cycles from two to one per year and providing a way for successful conservation of 19 mutant silkworm germplasm accessions.