Construction of Life-tables for Some Bi-voltine Crosses of Mulberry Silkworm (Bombyx Mori Linnaeus) Under Lab Condition

Abstract

The commercial production of silk is called as "Sericulture" Which is a labour intensive, agro-based cottage industry, ideally suitec1 not only to India but to all developing country of tropical belt. Mulberry Silk worm (Bombyx mori. L) is an monophagous and multivoltine insect without diapauses. The Present study entitled "Construction of Life-Tables for some Bi-Vol tine crosses of mulberry silkworm (Bomi>yx mori Linnaeus) under lab condition" was carried out on Sericulturc Research, Demonstration and Training Unit lab, Department of Entomology, College of Agriculture, S. V. P. Univers.ity of Agriculture and Technology Modipuram, Meerut (U .P.) during 2011-12. Investigations were undertaken to record the (j) Construction of age specific life table. (ii) Construction of stage specific life table (iii) C<nstruction of life and fertility table for female. The age specific life table revealed that the age specific survivorship on the two hybrid cross of mulberry silkworm viz, NB4D2xSII6 and KC2xFC1. The Bombyx mori L. hybrid cross NB4D2xSH6 took the shortest time 37 days to completes its generation while hybrid cross KC2xFC1 required the maximum, 43 d~ys. The apparent highest mortality rate was recorded on NB4D2xSH6 (14%) and the lowest (11%) or. KC2xFC1 at room temperature and the potential fecundity. Was recorded 333 o;; NB4D;;xSH6 and the lowest 314 on KC2xFC1 at control temperature. Based on the results obtained from the present study, it may be concluded that among the hybrids cross of mulb(Try silkworm NB.1D2xSH6 was the most economic hybrid cross of mulberry silkworm for the S·~riculture growers.