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Jeyarani S., Sathiah N., Karuppuchamy P. (2010): Field efficacy of Helicoverpa armigera nucleopolyhedrovirus isolates against H. armigera (Hübner) (Lepidoptera: Noctuidae) on cotton and chickpea in Tamil Nadu. Plant Protect. Sci., 46: 116-122.Field efficacy of seven geographical isolates of Helicoverpa armigera nucleopolyhedrovirus (HaNPV) along with an insecticide control was evaluated against H. armigera on cotton and chickpea in the Coimbatore district of Tamil Nadu, India. Among the HaNPV isolates, CBE I (Coimbatore) and NEG (Negamum) applied at 3.0 × 10 12 POB/ha to cotton and 1.5 × 10 12 POB/ha to chickpea with an adjuvant, crude sugar, significantly reduced the H. armigera larval population and increased the yield. CBE I and NEG recorded the highest yield of 2038 kg/ha and 2033 kg/ha, which was on a par with endosulfan (2026.7 kg/ha) with cost/benefit ratios of 1:2.32, 1:2.48, and 1:1.12, respectively, on cotton. In chickpea grain yields of 980, 983, and 973.3 kg/ha and cost/benefit ratios of 1:1.36, 1:1.48 and 1:0.87, respectively, in CBE I, NEG and endosulfan treated plots were obtained. The isolate RAJ (Rajasthan) recorded the lowest yield comparable to that of the untreated control in both crops.

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ABSTRACT. Okra (Abelmoschus esculentus(

Background: Parasitoid wasps have received a great share of heed in the biological control of pests. However, they are often difficult to identify because of their small body size and profound diversity. In this view, biodiversity indices of parasitic fauna was reckoned and proper identification of those biocontrol agents were done through morphological and molecular technique such as DNA barcoding.Methods: Biodiversity indices of parasitoid of Groundnut Leafminer (GLM), Aproaerema modicella Deventer were reckoned for three agroclimatic zones viz., Irrigated Eastern zone (IE), Rainfed zone (R) and Irrigated Western zone (IW) of Tamil Nadu. Biodiversity indices viz., Relative density, Simpson’s Index, Shannon-Wiener Index, Pielou’s Evenness Index, Margalef Index and Beta diversity were assessed for the parasitic fauna associated with GLM. Apart from this, morphological characterization of prominent parasitoids were done with the help of available literatures and taxonomic experts. The molecular characterization of parasitoids were done using mitochondrial Cytochrome Oxidase I (mtCOI).Result: The relative density of parasitoid families and species indicated the dominance of braconidae and Chelonus blackburni Cameron. Among the agroclimatic zones, rainfed zone had higher species diversity, richness and evenness. In addition, the morphological and molecular confirmation revealed that the parasitoids associated with A. modicella as Temelucha spp., Stenomesius japonicus, Bracon hebetor, Sympiesis dolichogaster, Chelonus blackburni and Avga choaspes. The amplified sequences were submitted to NCBI database and accession numbers were obtained.

Biopesticides are promising alternatives to chemical pesticides, and they have opened up new panorama in insect pest management to aid in the promotion of safe, eco-friendly pest management. They are relatively host specific and do not interfere with other biotic systems. Research concerning the development of biopesticides has focused mainly on identification of virulent isolates of bioagents for effective management of the target pests. However, information pertaining to their effects on natural enemies, non-target pests, and environment is scanty. In the present study, oil formulation of fungal pathogen, Beauveria bassiana (Bb 112) was tested against adults of Cryptolaemus montrouzieri Mulsant (Coleoptera:Coccinellidae), under laboratory condition. Oil formulation of B. bassiana (Bb 112) has been found to be safer to C. montrouzieri adults with maximum adult survival of 92.62 per cent at the highest dose (10 8 spores ml-1) and 100 per cent survival at lower dose tested (10 4 spores ml-1) respectively.

Microplot field trial was conducted from March to May 2017 to assess the efficacy of various biopesticides, pathogen, predator and parasitoid against M. vitrata on lablab (var. Co Gb 14). The experiments were carried out in a randomized block design (RBD) with nine treatments and three replications. Results revealed that spinosad 45% SC @ 75 ml ha-1 was significantly superior to all other treatments by recording a cumulative mean population reduction of 72.58 per cent. The next in the order of efficacy were emamectin benzoate 5% SG @ 200 ml ha-1 (65.16 %) > sequential application of emamectin benzoate (200 ml ha-1) + Bracon brevicornis (2000 adults ha-1 released after fortnight) (63.70%) > emamectin benzoate (100 ml ha-1) + B. brevicornis (1000 adults ha-1) @ half the dose each (62.06 %) > azadirachtin 0.03% @ 2.5 L ha-1 (39.33 %) > B. brevicornis @ 2000 adults ha-1(32.77 %) > Crude suspension of B. bassiana (Bb 112) @ 108 Spores ml-1 (25.95 %) > Xylocoris flavipes @ 40,000 adults ha-1 (20.22 %).