STANDARDIZATION OF PRESERVATION SCHEDULE FOR MULTIBIVOLTINE LAYINGS OF BOMBYX MORI L, A POTENTIAL BIO RESOURCE, IN THE TROPICS OF EASTERN INDIA

Disease free layings (dfls) of silkworm, Bombyx mori L., have to be consigned after production. Details study has been done to standardize the techniques of consignment of disease free layings of silkworm for prolong period in different condition in grainage. Layings of multibivoltine race collected after 24-30 hours of oviposition are processed and 30 samples of 5 difls (1 gm) each are consigned in 5°C and 80% relative humidity in walk-in-cold room controlled with microprocessor up to a maximum period of 115 days with double step consignment technique and decoldstored one by one after different period following specific techniques and their performances are tested over a control sample which was not consigned. Similar consignments of layings are done with another two sets collected after 36-40 hours and 44-50 hours of oviposition and their porformances are also tested with the control sample. The multibivoltine difls can safely be consigned in 5"C and in 80% RH up to a period of 25 days without sacrificing their yield attributing characters. The hatching of the difls can further be postponed by following double step consignment technique. The dils are started to 15°C for 48 hours to reach C and C. stage and then shifted to 2.5"C for longer period of consignment. Each of the cases the RH is strictly maintained up to 80%. By adopting double step consignment method the hatching of the multi x bivoltine difls can be postponed safely up to 85, 75 and 65 days for the layings of 24–30, 36-40 and 44-50 hours of oviposition, respectively.