A. Prabhuraj ¹, K. S. Girish ¹, Shivaleela ¹, B. V. Patil ¹

Affiliations
1 Department of Entomology, College of Agriculture, Raichur, 584101, Karnataka, IN

Abstract

A successful management strategy was developed against chickpea pod borer, Helecoverpa armigera (Hub) by integrating locally isolated entomopathogenic nematode, Heterorhabditis indica (RCR) with other entomopathogens like Helicoverpa armigera nuclear polyhedrosis virus (HaNPV) and Bacillus thuringiensis (Bt) and botanicals. Preliminary laboratory studies were conducted, to standardize the optimum dosage of nematodes required for field application, to evaluate the compatibility of nematode with entomopathogens and botanicals and their combinations. The optimum dosage of infective juveniles was standardized to third (LC₅₀ of 145 IJs/larva) and fourth (LC₅₀ of 195 IJs/larva) instars based on the concentration mortality response. Persistence study on chickpea foliage in field condition indicated that, infective juveniles along with 0.1 % glycerol survived better (80%) compared to other anti-dcssicants. In compatibility studies, though H. indica was compatible with other entomopathogens, but was susceptible to higher concentrations of aqueous leaf extracts of some selective botanicals. A series of laboratory bioassay was carried out to select best combinations of H. indica with other entomopathogens and botanicals against third and fourth instar H. armigera and these were tested in field for two consecutive years. Two year field evaluation indicated that, sequential application of H. indica + Prosopis juliflora (1 lakh IJs/I + 10%) at 50 and 75 days after sowing was superior with highest larval reduction (23.47%), minimum pod damage (11.27%) and maximum seed yield (19.24 q/h).

Keywords

Heterorhabditis indica, Helicoverpa armigera, Management, Chickpea, Botanicals, HaNPV, Entomopathogens, Mortality.

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A. Prabhuraj ¹, B. V. Patil ¹, K. S. Girish ¹, Shivaleela ¹

Affiliations
1 Department of Entomology, College of Agriculture, Raichur, 584 101, Karnataka, IN

Abstract

A field experiment was conducted at Agricultural College, Raichur, Karnataka to evaluate the effect of Heterorhabditis indica (RCR), an insect parasitic nematode in combination with other entomopathogens and botanicals against Helicoverpa armigera (Hübner) in chickpea ecosystem. Pooled data on per cent larval reduction after two sprays revealed that the highest reduction of 47.63 was achieved in chlorpyriphos/quinalphos (0.04/0.05%) treatment at seven days after spraying. However, sequential application of H. indica + Pa. pinnata (1.0 lakh IJs +2.5%) and H. indica + Pr. juliflora (1.0 lakh Us +10%) recorded maximum yield (1.96 and 1.83 kg/plot, respectively) with minimum pod damage (10.9 and 11.5 %, respectively). Thus there is a scope for integration of H. indica with botanicals viz. Pa. pinnata and Pr. juliflora for the effective management of chickpea pod borer.

Keywords

Bacillus thuringiensis, Heterorhabditis indica, Larval Reduction, Pongamia pinnata, Prosopis juliflora, Seed Yield.

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A. Prabhuraj ¹, B. V. Patil ¹, Shivaleela ¹, K. S. Girish ¹

Affiliations
1 Department of Entomology, College of Agriculture, University of Agricultural Sciences, Raichur 584 101, Karnataka, IN

Abstract

The bio-efficacy of Heterorhabditis indica Poinar in combination with Helicoverpa armigera nuclear polyhedrosis virus (HaNPV) against Helicoverpa armigera (Hiibner) was evaluated during 2002 in the laboratory. Results revealed thut combination of H. indica and HaNPV at all concentrations recorded highest mortality (100%) and were on par with alone inoculation of H. indica treatment, but significantly superior over HaNPV alone against third instar larva. Fourth instar larva suffered cent per cent mortality when inoculated with H. indica plus HaNPV at all concentrations after 48 h compared to H. indica alone (@ 200 Usl larva) which recorded 75 per cent mortality. The results indicate the synergistic effect when both the bioagents were combined against fourth instar larva.

Keywords

Entomopathogenic Nematode, HaNPV, Helicoverpa armigera, Heterorhabditis indica, Infective Juvenile.

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A. R. Prasanna ¹, V. B. Nargund ², M. Bheemanna ², B. V. Patil ²

Affiliations
1 Department of Entomology, G K V K, UAS, Bangalore, 650 065, IN
2 Department of Agricultural Entomology and Department of Pathology, College of Agriculture, University of Agricultural Sciences, Raichur 584 101, Karnataka, IN

Abstract

Laboratory experiment was conductcd to study the compatibility of 1 hiamethoxam 70WS with growth and sporulation of Trichoderma harzianum. There wn no inhibition of mycelial growth of T. harzianum in all the concentrations except at 1.25 percent. The spore count was 1xl0⁴ spores/ ml at seven days after inoculation of Trichoderma. The reduction in the radial growth of Rhizactonia solani was 40.2 percent in presence of T. harzianum whereas no inhibition was observed In thiamethoxam at 10g/kg seed. In combination with thiamethoxam at 2,85g/kg seed+Trichoderma, 4.28g/kg seed+Trichoderma and l0g/kg seed+Trichoderma, the reduction in radial growth of R. solani was 37,3, 35,95 and 32.4 percent, respectively. The study indicated that it is possible to use Trichoderma @ 4g/kg seed and thiamethoxam l0g/kg seed as seed treatment, which find a place in the integrated insect pest and disease management.

Keywords

Bioefficacy, Compatibility, Rhizoctonia solani, Seed Treatment, Thiamethoxam, Trichoderma.

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Mahabaleshwar Hegde ¹, K. Thulsi Ram ¹, B. V. Patil ¹

Affiliations
1 Department of Agricultural Entomology, College of Agriculture, Raichur - 584101, Karnataka, IN

Abstract

Interaction between the phytoseiid predator, Amblyseius longispinosus (Evans) and the red spider mite, Tetranychus macfarlanei Baker and Pritchard on cotton at ratios of 1:5, 1:10, 1:20 and 1:30 indicated that irrespective of prey ratios, the predator consumed sufficient numbers to counter the increasing prey population. The prey elimination was slightly prolonged at 1:10, 1:20 and 1:30 ratios whereas in case of 1:40 and 1:50 ratios, the prey population was not suppressed on potted cotton plants kept under green house condition, even after fifth week. The curves obtained by the functional and numerical responses between prey egg density and prey eggs destroyed and number of eggs laid by the predator, reached a plateau and the shape of the curves in both the responses is curvilinear.

Keywords

Amblyseius longispinosus, Functional and Numerical Responses, Interaction, Tetranychus macfarlanei.

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Mahabaleshwar Hegde ¹, B. V. Patil ¹

Affiliations
1 Department of Agricultural Entomology, College of Agriculture, Raichur, IN

Abstract

The phytosciid predator, Amblyseius longispinosusisp (Evans) has heen proved to he a very good predator of Tetranychid mites (Mallik, 1974). Biology of A.longispinisus has been studied on Tetranychus ludeni Zacher (Mallik, 1974) and Oligonychus indicus Hirst (Manjunatha, 1988; Anil, 1990). The feeding preference and feeding potential of the predator has been studied by Anil (1990) only on O. indicus. However, information on its biology, feeding potential and fceding preference on the red spider mite, Tetranychus macfarlanei Baker and Pritchard is not available and so experiments were conducted under laboratory conditions to study these parameters.

Keywords

Amblyseius longispinosus, Tetranychus marfarlanei, Biology, Feeding Potential, Preference.

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Mahabaleshwar Hegde ¹, B. V. Patil ¹

Affiliations
1 Department of Agrl. Entomology, College of Agriculture, Raichur, IN

Abstract

Mass rearing of different phytoseiid mites had been attempted using tetranychid mites (McMurthy and Scriven, 1965; Hoy et al., 1982; Karuppachamy et al., 1988; Anil, 1990). However, the mass rearing of Amblyseius longispinosus (Evans) on Tetranychus macfarlanei Baker and Pritchard has not been adequately studied and also the method employed earlier were a bit complicated, time consuming and difficult to commercialise. Therefore keeping these points in view, an experiment was conducted under laboratory condition.

Keywords

Amblyseius longispinosus, Tetranychus macfarlanei, Mass Rearing.

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Mahabaleshware Hegde ¹, B. V. Patil ¹

Affiliations
1 Department of Agricultural Entomology, College of Agriculture, Raichur, IN

Abstract

Red spider mite, Tetranychus macfarianei Baker and Pritchard assumed major pest status on cotton in Tungabhadra Project area of Karnataka (Patil, 1986). A potential phytoseiid predator Amblyseius longispinosus (Evans) was reported to occur in the same agro ecosystem (Thulsiram, 1991).

Keywords

Amblyseius longispinosus, Tetranychus macfarlanei, Toxicity, Pesticides.

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Shekharappa ¹, Somasekhar ¹, B. V. Patil ¹

Affiliations
1 Department of Agricultural Entomology, University of Agricultural Sciences, Raichur, Karnataka, IN

Abstract

The groundnut leafminer, Aproaerema modicella Deventer, is a serious insect pest of groundnut in many South Asian and South-East Asian countries. In India, it has been reported in severe form on groundnut from Karnataka (Usman and Puttarudraiah, 1955), Andhra Pradesh (Krishnamurthy Rao et al., (1962), Maharashtra and Tamil Nadu (Rai, 1976). The Leafminer however is attacked by many species of parasitoids in nature.

Keywords

Groundnut, Aproaerema modicella, Parasitoids.

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