1. KAUTIR (Kerala Agricultural University Theses Information and Retrieval)
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Item Studies on the granulosis virus of Pericallia ricini Fabricius (Arctiidae: Lepidoptera)(Department of Agricultural Entomology, College of Agriculture, Vellayani, 1978) Babu M Philip; Abraham JacobThe black headed hairy caterpillar, Pericallia ricini Fab., is a polyphagour pest feeding on a wide variety of crops such as castor, cotton, banana, cucurbits, sunflower, field beans, and gingelly. The occurrence of a granulosis in this insect was recorded in 1972, but no detailed studies have so far been made on this disease. A through knowledge of the disease including the host pathogen relationships and the physico-chemical properties of the pathogen is essential to judge its suitability in practical pest management programmes. With a view to collect these information the present studies were taken up. Studies were made in the laboratory and in field cages. Larvas of P. ricini reared in the laboratory on castor leaves were used. Third instar larvas were used in all studies except those on symptamatology and larval susceptibility. A purified suspension of granules derived from 300 dead larvae in 3 litres of distilled water formed the inoculam. All the experiment were conducted at room temperature and humidity.Item Nuclear polyhedrosis of Opisina arenosella WLK. (= Nephantis serinopa Meyr;) (Cryptophasidae: Lepidoptera) and its utility for the control of the pest(Department of Agricultural Entomology, College of Agriculture, Vellayani, 1985) Babu M Philip; Mohandas, NThe black headed caterpillar, Opising arenosella Hlk. (= Nephantis serinopa Meyrick) is a serious pest of coconut. The slender caterpillars found under the leaves in galleries made of silk and foreign matter feed on the chlorophyll tissues . Philip et al., (1982) reported the occurrence of a nuclear polyhedrosis virus in the larvae of O. arenosella. Basic information for judging the suitability of this pathogen for the control of the pest were lacking. Hence detailed studies were made on the symptamatology, morphology of the pathogen, histopathology, mode of transmission of the virus to the progeny, cross infectivity to other species of lepidoptera, bioassay of the virus , persistence of the virus on coconut foliage , effect of physical factors on the persistence of the virus, safety of the pathogen to non target organisms and the efficacy of the virusin controlling the pest in field.Item Investigations on nuclear polyhedrosis of black hairy caterpillar, Pericallia Ricini fabricius (Arctiidae: Lepidoptera)(Division of Entomology, College of Agriculture, Vellayani, 1975) Vasudevan Nair, K P; Abraham JacobDetailed investigations were carried out on the nuclear polyhedrosis of the black hairy caterpillar,Pericallia ricini (Arotiidae) covering symptomatology, larval susceptibility, effect of the virus on the larval moulting, changes in the number of circulating haemocytes in the infected larvae, nature of causative agent, effect of temperature and sunlight on the infectivity of the virus and the cross infectivity of the virus to other species of lepidoptera. The virus infected larvae exhibited a ll the typical symptoms of nuclear polyhedrosis infection as reported from other lepidopterous larvae. The larvae infected in the early instars appeared paler and thinner. The infected larvae showed loss of appetite and became sluggish. The dead or dying larvae showed the characteristic symptom of hanging head downwards from the top o f the containers with the aid of prolegs. In the advanced stages of infection the cuticle became fragile and it ruptured liberating the liquefied body contents. The susceptibility of the larvae to virus infection decreased with increase in the age of the larvae. The averageincubation period varied from 5*24 days for the second instar to 8 days for the sixth instar larvae. The virus infection inhibited moulting in the later stages of the disease. No significant difference was observed in the THC of healthy larvae and virus infected larvae up to 24 hours after inoculation; there was significant reduction in the THC of diseased larvae after 24 hours of inoculation.Item Phenotypic and molecular characterisation of phytophthora sp. inciting leaf fall of nutmeg(Department of Plant Pathology, College of Horticulture, Vellanikkara, 2015) Sumbula, V; Sally K Mathew