Evaluation of commercial traits in three strains of Eri Silkworm (Samia ricini) reared on different host plants

Abstract

This study evaluates the commercial traits of three eri silkworm (Samia cynthia ricini) strains—Green, Yellow, and Hybrid—reared on different host plant combinations: Local Green + Local Green castor, Local Green + Local Pink castor, and Local Green castor + Tapioca. Key parameters, including matured larval weight, fifth instar larval duration, cocoon weight, cocoon yield, shell weight, shell yield, shell ratio, silk productivity, and pupal weight, were assessed using a factorial Completely Randomized Design and analyzed via two-way ANOVA at a 5% significance level. Results revealed significant variations driven by host plants, strains, and their interactions. The Yellow strain reared on Local Green and Local Pink castor exhibited superior performance in matured larval weight (5.777 g), cocoon yield (70.55 kg/100 layings), silk productivity (8.067 cg/day), and pupal weight (2.18 g). The Hybrid strain on the same host plant combination achieved the highest cocoon weight (2.903 g) and shell weight (0.337 g). Shell yield and shell ratio were predominantly influenced by host plants, with Local Green and Local Pink castor proving optimal. Fifth instar larval duration was longest for the Yellow strain on Local Green castor and Tapioca (5.33 days). These findings underscore the critical role of host plant selection in optimizing eri silkworm performance and highlight the Yellow and Hybrid strains, when reared on Local Green and Local Pink castor, as ideal for maximizing silk production, offering valuable insights for sustainable sericulture practices in North-East India.