4 research outputs found
DEVELOPMENT OF A NEW BIVOLTINE BREED OF SILKWORM BOMBYX MORI YX MORI MU51 WITH SHORT LARVAL DURATION
No full textAn exotic bivoltine race of silkworm Bombyx mori namely C108, and an exotic multivoltine race pre, with known genetic background were utilized in different combinations in the cross breeding programme including test crossing and backcrossing at appropriate stages by following suitable selection procedure for the ten economic traits considers at every generation, a hardy new bivoltine breed MU51 is evolved, which is characterized by plain larvae spinning white oval cocoons with shorter larval duration (20-22 days) was isolated in the selected breeding experiment
Comparative study (I): On the longevity/ageing of pupa and adult moths in selected few multivoltine purelines of silkworm Bombyx mori (L) in all the seasons of the year.
Get PDFA comparative study utilizing the six multivoltines, in three seasons of the year between pupal and adult moth stage of silkworm of reveals a positive significance. Pupal duration was calculated after chrysalis stage among six multivoltines clearly indicated that the duration of pupae in the pre race is lowest where as the Daizo race exhibited the longest pupal duration of 240 hours. Silkworm adult life span evaluated in three seasons in the two sexes (male moth and female moth) it is clear that race pre exhibited shortest adult life span of 84 hours in mated males and 114 hours in mated females during pre-monsoon period and Daizo race revealed prolonged adult life span 222 hours in unmated males and 242 hours in unmated females during post-monsoon period.In the present studies among the two sexes, the unmated (virgin) male and females moths exhibited the longest life span than those of mated male and female moths. The influence of three seasons on adult life span is very clear from the experiment. The effect of pre-monsoon is more conspicuous (revealing short lifespan) where as in post-monsoon season lifespan is longest both in the pupal and adult.The results obtained from the present studies clearly demonstrate that racial differences, seasonal impact and sex wise differences are important in the expression of adult longevit
An attempt for Indoor rearing of tasar silkworm Antheraea mylitta Drury on Terminalia catappa in the natural atmospheric conditions of Mysuru
Get PDFThe non mulberry silkworm’s tasar, eri and muga are grown in hilly forest regions of north eastern part of India where climatic conditions are favourable and they feed on various wild food plants and many of them grown in plane lands for ornamental purpose. An attempt made to grow tasar silkworm Antheraea mylitta in the natural atmospheric conditions of Mysuru during the rainy season (June-September) by using the secondary food plant Terminalia catappa, resulted in the larval life span of 30 days on an average and the effective rate of rearing of 27%. The results were proved that the survivability ratio and the quantity and quality of the cocoons produced were found to be affected that may due to the new environmental conditions and secondary food plant provide
Comparative study (II): On the longevity of pupa and adult moths in selected few bivoltine purelines of silkworm Bombyx mori (L) in all the seasons of the year.
Get PDFA comparative study utilizing the six multivoltines, in three seasons of the year between pupal and adult moth stage of silkworm of reveals a positive significance. Pupal duration was calculated after chrysalis stage among six multivoltines clearly indicated that the duration of pupae in the pre race is lowest where as the Daizo race exhibited the longest pupal duration of 240 hours. Silkworm adult life span evaluated in three seasons in the two sexes (male moth and female moth) it is clear that race pre exhibited shortest adult life span of 84 hours in mated males and 114 hours in mated females during pre-monsoon period and Daizo race revealed prolonged adult life span 222 hours in unmated males and 242 hours in unmated females during post-monsoon period. In the present studies among the two sexes, the unmated (virgin) male and females moths exhibited the longest life span than those of mated male and female moths. The influence of three seasons on adult life span is very clear from the experiment. The effect of pre-monsoon is more conspicuous (revealing short lifespan) where as in post-monsoon season lifespan is longest both in the pupal and adult. The results obtained from the present studies clearly demonstrate that racial differences, seasonal impact and sex wise differences are important in the expression of adult longevity
