The Central Silk Board (CSB), the apex body of the Indian sericulture industry, is involved in developing new hybrids to improve bivoltine silk production in sub-tropical Northern India.
Among northern states, Jammu and Kashmir, Himachal Pradesh, and Uttaranchal are the traditional bivoltine silk producers in the region. Despite more potential for bivoltine silk in these states, their combined contribution remains low, when compared to other states like Karnataka, Andhra Pradesh, and Tamil Nadu. One of the major reasons for such a low production is lack of region-specific and acclimatised productive hybrids, CSB officials said.
Currently, ?SH6? and ?NB4D2? variety silkworm breeds are widely used, irrespective of season and environmental conditions in these states.
In this perspective, officials said the Regional Sericultural Research Station (RSRS) in Jammu, initiated a silkworm breeding programme for developing new breeds and potential hybrids for use in two potential rearing seasons in the sub-tropical belts of these three states.
Accordingly, RSRS has developed a new breed christened RSJ, which raised hopes in the silk rearing community in the northern states, officials added.
In fact, RSJ breeds have been evolved through the systematic breeding programmes at RSRS. The newly found RSJ breeds were subjected to a preliminary combining ability evaluation, and subsequently two hybrids in the RSJ combination were selected for field trials for the spring and autumn seasons.
According to CSB, the yield potential of the spring specific RSJ combination breed is 70-80 kg/100 dfls (disease free layings), as against 65-75 kg/100 dfls produced from traditional hybrids. The potential yield of the autumn specific RSJ hybrid is 50-60 kg/100 dfls, as against 40-50 kg/100 dfls produced from the traditional hybrid. The field trials of RSJ hybrids conducted through the department of sericulture in J&K, Punjab, and Uttaranchal, have confirmed their superiority over the current hybrids like SH6 and NB4D2 in various economic traits, yield, and cocoon characteristics in particular.