Journal of Environment and Sociobiology

Subrata Trivedi ¹, Kunal Sarkar ¹, Susanta Kumar Chattopadhyay ¹, Gopinath Baur ¹, Manmatha Mandal ¹, Somdip Majumdar ¹

Affiliations
1 Department of Sericulture, Krishnath College, Berhampore, Murshidabad-742101, West Bengal, IN

Abstract

Of all factors that govern productivity in sericulture, the role of silkworm egg is of prime importance. It is the sheet anchor of sericulture industry. Timely supply of appropriate quality and adequate quantity of disease free silkworm eggs to the sericulturists is crucial for successful harvest of cocoon crops. Silk moths have a tendency to pair immediately after emergence from cocoons. The present study indicates that in case of N×M₁₂W, N×NB₄D₂ and N×YB crossbreeds at least 95%-99% fertilized eggs can be procured by using a single male moth for 4 times in crossing. So, if male moths are used 4 times during multiple crossing it would not affect the fertility of eggs. The present investigation also reveals that total fecundity almost remained same with control when male moths were even used for seven times in crossing. This suggests that that a single male moth can be used for four times by giving them sufficient rest in crossing with female moth and in this way a grainure can save considerable cost and hazards during the purchasing of seed cocoons of male components.

Keywords

Bombyx mori, Multiple Crossing, Silkworm Eggs, Fecundity, Fertilized and Unfertilized Eggs.

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Subrata Trivedi ¹, Gopinath Baur ¹, Somdip Majumdar ¹, Alak Ranjan Goswami ¹

Affiliations
1 Department of Sericulture, Krishnath College, Berhampore, Murshidabad-742101, West Bengal, IN

Abstract

Mulberry is the host of the pathogens of different parasitic diseases. In West Bengal three fungal foliar diseases, viz., Powdery mildew, Leaf spot and Leaf rust, one fungal Root Rot, one bacterial Leaf blight and one nematode infected Root knot (in some restricted places of West Bengal) are common. They may cross economic threshold level every year and cause total 25-30% crop loss on an average. These diseases, their symptoms, causal organisms, occurrence and control measures have been discussed.

Keywords

Mulberry, Diseases, West Bengal.

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Kunal Sarkar ¹, Gopinath Baur ¹, Somdip Majumdar ¹

Affiliations
1 Post Graduate Department of Sericulture, K. N. College, Berhampore, Murshidabad-742101, West Bengal, IN

Abstract

Mulberry plants are seriously damaged by various types of sap sucking insect pests in West Bengal. Most remarkable sapsuckers are mealy bug, white fly and thrips. Mealy bug sucks nutrient rich plant sap from tender top and injects toxic saliva to it causing serious morpho-physiological abnormality called 'Tukra'. White fly is a major sap sucking minute polyphagous pest which seriously damages the crop by sucking the plant sap from leaves and young shoots and secretes honey dew to welcome other sooty moulds. Thrips, both nymphs and adults, tear the epidermal leaf tissues with their stylets and suck the plant sap causing low nutritive value of leaves.

Keywords

Insect Pests, Tukra, Whitefly, Thrips.

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