Performance of Eri Silkworm (Samia ricini Donovan) on Primary and Secondary Host Plants in Assam: A Seasonal Analysis of Cocoon Characteristics

The present study evaluated the influence of different host plants on cocoon characteristics of eri silkworm (Samia ricini Donovan) on primary (Castor, Ricinus communis) and secondary (Kesseru, Heteropanax fragrans; Tapioca, Manihot esculenta) host plants in Assam, focusing on cocoon shell weight, pupal weight and shell ratio. Cocoon and pupal parameters were highest with Castor, followed by Tapioca, with Kesseru recording the lowest values. The findings are in conformity with earlier reports highlighting castor as the most suitable host plant for eri silkworm owing to its superior leaf nutritive value and positive influence on larval growth and cocoon traits. Kesseru, although less efficient, still contributed to silkworm production under certain conditions, with seasonal variations playing a critical role in determining the success of rearing. Overall, the study underscores the significant role of host plant and season in determining cocoon quality and productivity of eri silkworm under Assam agro-climatic conditions.