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ThesisItem Open Access EXPLOITATION OF Nomuraea rileyi (FARLOW) SAMSON AGAINST IMPORTANT LEPIDOPTEROUS PESTS OF POTATO, COTTON AND CHICKPEA(University of Agricultural Science, Dharwad, 2001) Hegde, Rajendra; Lingappa, S"Investigations were carried out from 1999 to 2001 at the main campus of the University of Agricultural Sciences, Dharwad to evaluate the pathogenicity of Nomuraea rileyi against important pests and beneficial insects, to establish the field effectiveness of the mycopathogen in potato and chickpea, to know the effect of habitat manipulation to enhance N. rileyi, to evaluate natural substrates for mass production of the fungus and to assess the agrochemical compatibility with the fungus. The fungus proved pathogenic to Helicoverpa armigera, Spodoptera litura, Thysanoplusia orichalcea, Agrotis spp., IVIythimna separata and Chilo partellus. The mycopathogen @ 2 x 10^ conidia /1 sprayed thrice against S. litura in potato at 1 5 days interval from 50 days after sowing proved as effective as SINPV and Bt and reduced the defoliator upto 32 per cent. Increase in tuber yield due to entomofungal protection was upto 21 per cent over untreated and the incremental benefit considerably higher (9.32) compared to SINPV (2.93), Bt (3.01) and chemical protection (4.21). Lucerne and groundnut intercropping in cotton favoured incidence of the mycopathogen on H. armigera and in these habitats cotton experienced significantly lowered larval density and fruiting body damage than untreated control. Though kapas yield was maximum in chemical control (13.56 q/ha), with the addition of cotton equivalent yield of intercrops, both cotton + lucerne and cotton + groundnut systems proved equally productive. Cotton + lucerne intercropping system proved highly profitable. In chickpea, N. rileyi @ 2 x 10^ conidia/l proved as effective as HaNPV and Bt in restricting the larval load of H. armigera in the early part of crop growth but failed to establish superiority in lowering the pod damage. In cost effectiveness it (5.59) was next to NSKE (10.23). Rice and barley were the most suitable substrates for quicker and better mass multiplication of N. rileyi \NWh 1.22 x 10^ and 1.1 7 x 10^ conidia/g of substrates after 20 days of inoculation followed by sorghum, bajra, maize and setaria which prolonged harvest time. Fungicides proved highly toxic to the fungal pathogen in vitro by inhibiting 82.71 per cent conidial germination compared to insecticides (53.99%) and weedicides (21.50%). Endosulfan, carbaryl, thiodicarb, deltamethrin, fenvalerate and alphamethrin were highly detrimental to the entomopathogenic fungus."ThesisItem Open Access Exploitation of Nomuraea rileyi (Farlow) samson against important Lepidopterous pests of Potato, Cotton and Chickpea(University of Agricultural Sciences ;Dharwad, 2001) Hegde, Rajendra; Lingappa, S.