• International Journal of Industrial Entomology and Biomaterials
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• 제17권1호
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• pp.153-155
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• 2008

Pathogenic infection in tasar silkworm, Antheraea mylitta Drury is common and there is a breed specific response regarding tolerance. Hence, the tolerance level of three eco-races of tasar silkworm viz. Daba, Sarihan and Raily to Antheraea mylitta cytoplasmic polyhedrosis virus (AmCPV) infection was tested. The survival of Daba, Sarihan and Raily eco-races was significantly different (p<0.05) when challenged with the same concentration ($1{\times}10^5$ polyhedra/ml) of AmCPV. Daba eco-race was more tolerant to the AmCPV infection having higher survival (65.7%) and $LC_{50}$ values (1000893.17 polyhedra/ml) of AmCPV followed by Sarihan eco-race (50.7% survival and $LC_{50}$ value of AmCPV 187203.6168 polyhedra/ml) and Raily eco-race (24.3% survival and $LC_{50}$ value of AmCPV 5176.37 polyhedra/ml). The tolerance level of Daba and Sarihan eco-races against AmCPV was more than two times than Raily eco-race.

• International Journal of Industrial Entomology and Biomaterials
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• 제20권1호
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• pp.13-17
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• 2010

Ten numbers of plants, based on their medicinal value, were used to test their efficacy against virosis (caused by cytoplassmic polyhedrosis virus) in tasar silkworm, Antheraea mylitta Drury. in indoor rearing conditions. The aqueous extracts of leaf of Azadirichita indica (neem), Acharanthus aspera, Psoralea corylifolia, Asparagus racemosus, Adhatoda zelanica (Basak), Andrographis paniculata (Kalmegh), Moringa oilephera (sahjan), whole plant of Phyllanthus urinaria (Bhuiamla), Centella asiatica (Veng sag) and Curcuma longa (Haldi powder) in different concentrations were used for containment of virosis in silkworm larvae. The tasar silkworm larvae were orally inoculated with PIBs ($1\times10^6$) of AmCPV in $2^{nd}$ instar and treated with plant extracts in each instar ($2^{rd}$ instar onwards). The mortality due to virosis was recorded during larval period. The plant extracts, irrespective of their concentrations, were found effective in suppressing the virosis where P. urinaria reduced the virosis to 56.90% followed by A. paniculata (53.82%) and least in C. asiatica (5.15%). The lowest pooled larva mortality 36.99% was recorded in the treatment of P. urinaria. Comparatively higher larva mortality 39.91% was observed with the treatment of A. paniculata. The highest larva mortality in treatment was with C. asiatica (81.99%). In treated control larva mortality was 86.50%.

• International Journal of Industrial Entomology and Biomaterials
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• 제10권1호
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• pp.69-72
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• 2005

Bleaching powder solution (1 to $5\%$), slaked lime solution (0.1 to $0.5\%$) and formalin (1 and $2\%$) were tested for their efficacy against cytoplasmic polyhedrosis virus and Nosema mylittansis spores to control virosis and pebrine respectively in tasar silkworm, Antheraea mylitta in indoor rearing condition. All the disinfectants tested were found effective in suppressing the infection of virosis and pebrine significantly. Complete inactivation of Antheraea mylitta cytoplasmic polyhedrosis virus (AmCPV) was recorded when treated with $4\%$ bleaching powder, $0.4\%$ slaked lime for 20 min and $2.0\%$ formalin for 30 min. Similarly treatments of $3.0\%$ bleaching powder solution for 20 min and $2.0\%$ formalin for 30 min were found effective in complete inactivation of N. mylittanis spores.

• International Journal of Industrial Entomology and Biomaterials
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• 제13권2호
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• pp.97-101
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• 2006

The efficacy of wood ash from Terminalia arjuna (arjun) and T. tomentosa (asan) has been tested against virosis of tasar silkworm, Antheraea. mylitta D. The Polyhedral Occlusion Bodies (POBs) of Cytoplasmic Polyhedrosis Virus of A. mylitta (AmCPV) were exposed to the aqueous solution (0.5 to 4%) of wood ash for 5 to 30 minutes. The treated suspension of POBs was orally inoculated once to tasar silkworm larvae after 24 hours of $1^{st}$ moult, and larvae reared in indoor on arjun leaves till spinning. The application of aqueous solution of wood ash has established its potential as antiviral agent against cytoplasmic polyhedrosis virus. Two percent aqueous solution of wood ash from arjun and asan dissolved the Polyhedral Occlusion Bodies (POBs) of cytoplasmic polyhedrosis virus of tasar silkworm and inactivated the virions within a short period of 20 to 30 minutes. In vivo efficacy of aqueous solution of wood ash resulted in reduction of larval mortality due to virosis. The mortality was reduced to $2.56{\pm}0.21\;and\;3.03{\pm}0.32%$ when treatment of 2.0% solution of wood ash of arjun and asan respectively were applied for 20 minutes, compared to inoculated control $(92.18{\pm}7.52%)$. No mortality was recorded when treatment of 2.5% solution of wood ash of arjun and asan were applied for 10 minutes or more.