H. K. Jyothi ¹, G. Veeranna ¹, Geetha Bali ²

Affiliations
1 Karnataka State Sericulture Research and Development Institute, Thalaghattapura, Bangalore 560 062, Karnataka, IN
2 Bangalore University, Jnana Bharathi, Bangalore 560056, Karnataka, IN

Abstract

Biology of Dirhinus anthracia Walker was investigated on its natural host, Exorista bombycis Louis at six constant temperatures (10-35°C). The lower threshold for development for male and female was 10.5° and 11°C, respectively. Entire development from egg to adult required 475.05 and 550.96 day degrees, respectively for male and female. Sex ratio was in favour of female at all temperatures except 35°C where a reversal of sex ratio was observed. Reduction in doubling time and generation time was observed as temperature increased.

Keywords

Dirhinus anthracia, Exorista bombycis, Parasitoid, Temperature, Uzi Fly.

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M. R. Nirmala ¹, G. Veeranna ¹

Affiliations
1 Karnataka State Sericulture Research and Development Institute, Thalaghattapura, Bangalore 560 062, Karnataka, IN

Abstract

Biology of indigenous parasitoids namely. Trichopria sp., Exoristobia philippinensis Ashmead and Spalangia endius Walker of the uzi fly Exorista bombycis Louis was studied in the laboratory. All the parasitoids lived significantly longer in the presence of host and diet compared to either diet or host. They preferred to parasitize 2-4 days old host pupae and per cent parasitism was highest (4.23,5.0 and 8.43) on this age group. Adult parasitoids mated soon after emergence. The average fecundity was higher in E. philippinensis and Trichopria sp. compared to S. endius. Arrhenotokous parthenogenesis occurred in all the three species of parasitoids.

Keywords

Biology, Exorista bombycis, Exoristobia philippinensis, Gregarious parasitoid, Spazangia endius, TrichopriaSp.

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H. K. Jyothi ¹, G. Veeranna ¹, Geetha Bali ²

Affiliations
1 Karnataka State Sericulture Research and Development Institute, Thalghattapura, Bangalore 560062, Karnataka, IN
2 Department of Zoology, Bangalore University, Bangalore 560 056, Karnataka, IN

Abstract

Possibility of low temperature storage of indigenous hymenopteran parasitoids of uzi fly (Exorista bombycis Louis) namely, Nesolynx thymus (Girault), Dirhinus anthracia Walker and Pachycrepoideus veerannai Narendran and AniI at various stages of life cycle, was investigated. Egg, larvae, pupae and adults of all the three parasitoids died when stored at 5 and 1 ODC. However, Dirhinus anthracia and Pachycrepoideus veerannai could be stored for 90 and 45 days, respectively at 15°C without hampering their reproductive potential. With increase in the duration of storage, a reduction in the adult parasitoid longevity and fecundity at ambient temperature was noticed.

Keywords

Dirhinus anthracia, Exorista bombycis, Nesolynx thymus, Pachycrepoideus veerannai, Storage, Uzi Fly.

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G. Veeranna ¹, M. R. Nirmala ¹

Affiliations
1 Entomology Unit, Karnataka State Sericulture Development Institute, Thalaghattapura, Bangalore - 560 062, IN

Abstract

The uzifly Exorista sorbillans Wied. is a serious larval endoparasite of silkworm, Bombyx mori L. causing heavy damage to an extent of 15-20% to sericulture industry (Mukherjee, 1919; Gosh, 1949; Jolly, 1981; Kasturi Bai et al., 1986). Biological control methods have gained increasing acceptance and popularity because of its specificity to target pest and also being non-hazardous to human welfare, attempts are being made to contain uzifly menace using its parasitoids. Several larval/pupal parasitoids of E. sorbillans have been recorded. They are Nesolynx thymus (Pradip Kumar et al., 1986), Trichopria sp, Exoristibia philippinensis (Veeranna et al., 1987 a; 1987 b), Dirhinus anthracia, Pachycrepoideus veerannai (Veeranna and Jyothi, 1988. 1991), Spilomicrus karnatakensis (Pradip Kumar et al., 1988) and Brachymeria lugubris (Samson and Ramadevi, 1985). In this report, yet another parasitoid Spalangia endius Walker of E. sorbillans has been reported for the first time. The life cycle of this species and its population growth rate have also been studied. The identity of S. endius was established by Dr.T.C.Narendran, Professor of Zoology, University of Calicut, India.

Keywords

Uzifly, Exorista sorbillans, Parasitoid, Spalangia endius.

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