Abstract

                                Autumn silkworm crop is distinguished by high temperature and high humidity in Jammu and there is an urgent need to develop hardy bivoltine breeds/hybrids, which can withstand the autumn conditions of Jammu region to make sericulture activity profitable in the traditional sericultural state of Jammu and Kashmir. Though mulberry leaves are available in plenty during this season the silkworm crop during autumn season is generally a failure in Northern India. In order to identify suitable silkworm races, selected bivoltine silkworm germplasm were evaluated under abiotic stress conditions of high temperature and high humidity prevailing during autumn season in Northern India. Ten test accessions out of 230 bivoltine silkworm accessions were selected based on economically important rearing and post cocoon parameters and evaluated in the RSRS, Jammu conditions. The accessions were BBE-0173, BBE-0174, BBE-0178, BBE-0186, BBE-0189, BBE-0192, BBE-0198, BBE-0226, BBI-0239 and BBE-0266 with two control accessions (one local, ie., BBI-0116 for Jammu) and one common national control ie., BBI-0290). Six trials were conducted in the location in both the favourable (Spring) and unfavourable (Autumn) seasons. Test accessions BBE-0178 and BBE-0266 performed better during both spring and autumn seasons not only for rearing traits but also for post cocoon parameters. These accessions can be used to evolve suitable silk worm breeds or breed combinations through breeding programmes to stabilize autumn crop rearing.

Key words : Germplasm, Abiotic stress, Bivoltine Accessions, Spring, Autumn