New Bivoltine Hybrids of the Silkworm (Bombyx mori L.) Performance at Farmer’s Site

Abstract

The rise in atmospheric temperature, due to global warming, offers a great challenge to make a successful cocoon harvest, as it not only affects the progression of the larvae but also leads to outbreak of diseases. Thus, silkworm breeds have potential to thrive well under such harsh fluctuating climatic conditions without sacrificing commercial traits of cocoon and silk are in-need. Towards this, new bivoltine breeds developed employing heat shock technology, for the first time, were used to develop four bivoltine double hybrids (NBH1 × FC1, NBH2 x FC1, FC1 x NBH1, and FC1 x NBH2) and two poly hybrids (PM x NBH1 and PM x NBH2) and subjected to evaluation for their performance at the farmer's site. Notably, all four double hybrids distributed to farmers performed very well with substantial cocoon yield. Among them, NBH1 x FC1 and NBH2 x FC1 were outperformed with their high fecundity (675 and 700 eggs/dfl) and cocoon yield of 549 and 228 kg, out of 579 and 225 dfls reared by the farmers respectively. On the other hand, 360 and 248 kg of cocoons were harvested as against a total of 325 dfls and 250 dfls of PM x NBH1 and PM x NBH2 distributed to farmers. Eventually, all the farmers were delighted to rear these new double hybrids and poly hybrids, as it fetched a good price to sell the cocoons. Thus, we suggest all these new double hybrids and poly hybrids shall be used for large-scale silkworm rearing in the field conquering the climate change threat to produce both qualitatively and quantitatively better cocoons and silk that shall protect the wealth of Seri-farmers and silk reelers