R. K. Gupta ¹, T. C. Narendran ²

Affiliations
1 Division of Entomology, Sher-e-Kashmir University of Agricultural Sciences and Technology Jammu, FOA, Udheywalla, Jammu, 180 002, J & K, IN
2 Department of Zoology, University of Calicut - 673635, Kerala, IN

Abstract

Three species of braconid parasitoids viz, Glyptapanteles agamemnonis Wilkinson, Meteorus sp. and Cotesia ruficrus (Haliday) were recovered from the field collected larvae of Spilosoma obliqua Walker feeding on cultivated Vigna mungo and wild weeds, Xanthium strumarium and Parthenium hysterophorus during kharif 2002 and 2003 in Jammu (J & K). Besides, the prevalence of one ichneumonid parasitoid Agathis sp. and viral disease (Nucleopolyhedrovirus) was also noticed. Meteorus sp. Was considered as most promising parasitoid of this pest with a maximum parasitizatiou of 77.0 percent. Nevertheless, G. agamemuonsis is reported for the first time on S. obliqua in India. While, G agamemuonsis was recovered from the larvae feeding on all the three hosts viz Vigna mungo, Parthenium hysterophorus and Xanthium strumarium, Meteorus sp. was never recovered from P. hysterophorus. However, both these parasitoid co-existed in nature and found together attacking 3-4^th instar larvae from September to October (37-43 SW) with a peak activity within a minimum temperature range of 14.0 to 18.0°C. The natural parasitism by these parasitoids did not reveal significant correlation with aboitic factors, but the relationship between their respective K-valucs and larval density fit into density dependent model K = aN^b. However, C. ruficrus and Agathis sp. were noticed in later season when the mean minimum temperature reached below 10°C. The behaviour and developmental biology of all the three braconid parasitoids of S. obliqua is described.

Keywords

Cotesia ruficrus, Developmental Biology, Field Parasitism, Glyptapanteles agamemnonis, Meteorus sp., Spilosoma obliqua.

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R. K. Gupta ¹, Desh Raj ¹

Affiliations
1 Sher-e-kashmir University of Agricultural Science & Technology Division of Entomology, FOA, Udheywalla Jammu 180002, Jammu and Kashmir, IN

Abstract

Helicoverpa armigera (Hubner) larvae on chickpea were found to be parasitized by Apanteles sp., Diadegema fenestrale (Holmgren) and Campoielis chlorideae Uchida at Palampur, during two consecutive years. Among these, parasitization by the former two parasitoids remained negligible. However, the extent of parasitism by C. chlorideae ranged from 8.33 to 28.00 per cent. The parasitoid remained active from 2^nd week of April to 1^st week of May. Activity of the parasitoid ceased when the mean maximum temperature reached above 40°C and a significant positive correlation with total rainfall was observed. Multiple regression analysis revealed significant effect of relative humidity and total rainfall on larval parasitism, both individually as well as in association with other abiotic factors to the extent of 74.15 per cent.

Keywords

Campoletis chlorideae, Helicoverpa armigera, Parasitism, Parasitoids, Seasonal Incidence.

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Mudasir Gani ¹, S. Chouhan ¹, Babu Lal ¹, R. K. Gupta ², Gulab Khan ¹, N. Bharath Kumar ¹, Pawan Saini ¹, M. K. Ghosh ¹

Affiliations
1 Silkworm Pathology Laboratory, Central Sericultural Research & Training Institute, Central Silk Board, Ministry of Textiles, Government of India, Pampore - 192121, Jammu & Kashmir, IN
2 Biocontrol Laboratory, Division of Entomology, Sher-e-Kashmir University of Agricultural Sciences and Technology- Jammu, Chatha - 180009, Jammu & Kashmir, IN

Abstract

The mulberry silkworm Bombyx mori (L.) (Lepidoptera: Bombycidae) is infected with a baculovirus, Bombyx mori nucleopolyhedrovirus (BmNPV) that causes grasserie disease in silkworm and major economic losses to the silk industry. In India, >50 % of silk cocoon crop losses are attributed to BmNPV infection. Presently, there are no specific preventive measures for the occurrence and spread of BmNPV infection other than sanitized rearing methods, the only commercial practice today is to discard large stocks of worms in case of infection. Although diagnostic kits for detection of BmNPV have been developed, they are not extensively used on a commercial scale and subsequently, they fail to provide the indispensable and timely advantages desired for early disease intervention. The best emerging technology is the use of antibody–based biosensors and lateral flow assays, which have high specificity, sensitivity and the option of “on– site” pathogen detection. The use of disease resistant silkworm breeds or the utilization of inherent resistance in silkworm would be the most economical and effective way to prevent the occurrence of grasserie disease. Further, there is a great need to comprehensively analyze the host genes response to BmNPV infection and its functional analysis to prevent virus replication and its horizontal transmission.

Keywords

Antibody, Biosensor, Bombyx mori, Lateral Flow Assay, Management, Nucleopolyhedrovirus.

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