Assessment of Stable Strains of Eri Silkworms (Samia ricini) for Commercial Silk Production under the Climate of Manipur

Abstract

Aims: This study evaluates the performance of six Eri silkworm (Samia ricini) strains across multiple quantitative traits to identify the most suitable rearing period and stable strains for commercial silk production in Northeast India. Study Design: A field experiment was conducted to assessed the productivity and stability of different Eri silkworm strains across four seasons. Place and Duration of Study: The study was carried out in Imphal, Manipur, over four different rearing seasons. Methodology: Six Eri silkworm strains were evaluated for eight quantitative traits, hatching percentage, fecundity, effective rate of rearing, larval weight, pupation rate, single shell weight, single cocoon weight and shell percentage. Data were collected across four seasons, and hierarchical clustering analysis was performed to classify the strains based on genetic and phenotypic similarities. Results: The findings indicate that the April-May season provides optimal rearing conditions, resulting in higher survival rates, improved fecundity, and superior silk yield compared to other seasons. The Yellow Zebra strain performed consistently across multiple attributes and seasons, showing the highest stability among the strains that were studied. Hierarchical clustering analysis grouped the strains into three distinct clusters, reflecting their genetic and phenotypic relationships. Conclusion: The identification of stable strains and optimal rearing periods is crucial for enhancing Eri silkworm productivity and sustainability. These findings provide a scientific basis for strain selection and breeding strategies, benefiting both farmers and researchers involved in Eri silk production.