A S Vastrad
University of Agricultural sciences Dharwad, Agril. Entomology, Faculty Member
Study on seasonal incidence of Aphis gossypii infecting chilli was carried out at College Farm, UAS Dharwad, during rabi 2018-19. The crop was grown in a plot size 20x20 m with spacing of 60x60 cm. The aphid population was recorded on... more
Study on seasonal incidence of Aphis gossypii infecting chilli was carried out at College Farm, UAS Dharwad, during rabi 2018-19. The crop was grown in a plot size 20x20 m with spacing of 60x60 cm. The aphid population was recorded on chilli from 6 th Week After Transplanting (WAT) (2.37 aphids leaf-1) and reached to a peak level of 32.20 aphids leaf-1 during 10 th WAT. Later it followed decreasing trend and attained least incidence of 6.50 aphids leaf-1 at 14 th WAT. Among the two natural enemies investigated, ladybird beetle showed significant positive correlation (r=0.560) with aphid incidence whereas, non-significant positive association noticed with green lacewing population (r= 0.429).
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This study evaluated the biochemical changes in 15 chickpea genotypes artificially infested with pod borer Helicoverpa armigera (Hubner). Infested samples revealed significantly more phenols, malic acid and protein, and less reducing... more
This study evaluated the biochemical changes in 15 chickpea genotypes artificially infested with pod borer Helicoverpa armigera (Hubner). Infested samples revealed significantly more phenols, malic acid and protein, and less reducing sugar contents. Significant differences among the genotypes for all the biochemicals were observed in the infested samples. These differences were influenced by genotype and pod damage both individually and together. Correlation analysis indicated significant associations of parameters with pod damage.
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Combined treatment of chitosan and Pseudomonas spp.induced a significant increase in the activities of polyphenoloxidase (PPO), peroxidase (POD), chitinase, phenylammonia lyase (PALase) and enhanced the content of phenolic compounds in... more
Combined treatment of chitosan and Pseudomonas spp.induced a significant increase in the activities of polyphenoloxidase (PPO), peroxidase (POD), chitinase, phenylammonia lyase (PALase) and enhanced the content of phenolic compounds in tomato plants. Application of Pseudomonas spp.in combination with chitosan reduced the severity of Tomato leaf curl virus (ToLCV) diseased plants by 75–100% at 45 days after inoculation (DAI) relative to ToLCV control. Application of chitosan or the bacterial inoculant alone was not very effective. The plants inoculated with a mixture of Pseudomonas spp.(206(4) +B-15+ JK-16) + Chitosan recorded the highest phenol content, peroxidase activity, polyphenol oxidase activity, chitinase activity and PALase activity (65.78%, 110.59%, 95.65, 69.26 and 71.76% higher than the diseased control, respectively). This treatment also recorded maximum plant height, biomass and chlorophyll content, which were increased by 86.42, 41.27 and 91.50 per cent, respectively o...
Research Interests: Horticulture and Biology
Abstract: Studies on release and recovery of native parasitoids viz. Megastigmus sp and Aprostocetus gala Walker of eucalyptus gall wasp, Leptocybe invasa Fisher & La Salle, were conducted during 2008-09. The results indicated that there... more
Abstract: Studies on release and recovery of native parasitoids viz. Megastigmus sp and Aprostocetus gala Walker of eucalyptus gall wasp, Leptocybe invasa Fisher & La Salle, were conducted during 2008-09. The results indicated that there was a gradual increase in the per cent ...
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... M. Sc. (Agri.) Thesis, Univ. Agric. Sci., Dharwad (India). Thangavel, P., Balagurunathan, R., Divakaran, J. and Prabhakaran, I., 2003, Effect of vermiwash and vermicast extract on soil nutrient status, growth and yield of paddy. Adv.... more
... M. Sc. (Agri.) Thesis, Univ. Agric. Sci., Dharwad (India). Thangavel, P., Balagurunathan, R., Divakaran, J. and Prabhakaran, I., 2003, Effect of vermiwash and vermicast extract on soil nutrient status, growth and yield of paddy. Adv. Plant Sci., 16 (1): 187-190. ...
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The genus Megastigmus was described by Dalman in 1820 with Pteromalus bipunctatus Swederus as its type species. This genus belongs to the subfamily Megastigminae of the family Torymidae. This genus consists of 133 species worldwide of... more
The genus Megastigmus was described by Dalman in 1820 with Pteromalus bipunctatus Swederus as its type species. This genus belongs to the subfamily Megastigminae of the family Torymidae. This genus consists of 133 species worldwide of which 20 species were reported from the Oriental Region and 8 species from India (Noyes, 2003; Sure shan, 2009). Most species are phytophagous but some are parasitic in gall-forming insects (Narendran, 1994; Noyes, 2003). In this paper, two new species viz., Megastigmus sonneratiae Narendran and Girish Kumar sp. nov. emerged from the leaf galls of the mangrove plant Sonneratia apetala Buch. Ham and Megastigmus dharwadicus Narendran and Vastrad sp. nov. emerged from the galls of Eucalyptus, are described. The new species M. dharwadicus is an important parasitoid of Leptocybe invasa Fisher and LaSalle which is a serious invasive pest (Narendran, 2007; Mendel et al., 2004) of Eucalyptus in India and adjacent countries. A revised key to separate Indian spe...
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Studies conducted on ovicidal action of methomyl, profenophos, cypermethrin, thiodicarb, fipronil, polytrin C-44, lufenuron, fenvelerate + sesame oil and fenvelerate + honge oil revealed that profenofos and combinations of fenvalerate +... more
Studies conducted on ovicidal action of methomyl, profenophos, cypermethrin, thiodicarb, fipronil, polytrin C-44, lufenuron, fenvelerate + sesame oil and fenvelerate + honge oil revealed that profenofos and combinations of fenvalerate + honge oil and fenvalerate + sesame oil caused 57.85 to 69.26% egg mortality of P. xylostella and were significantly superior to other treatments. Among the vegetable oils tested alone, honge oil recorded significantly higher egg mortality (17.18 per cent) than sesame oil (9.50 per cent). The egg mortality was generally higher on the upper leaf surface (60.55%) than the lower (39.12%).
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Investigations were carried out to assess the efficacy of Maharastra isolates of Bacillus thuringiensis against lepidopteran insects viz., cabbage leaf webber, Diamond Back Moth and bioassays were also done to assess its safety to... more
Investigations were carried out to assess the efficacy of Maharastra isolates of Bacillus thuringiensis against lepidopteran insects viz., cabbage leaf webber, Diamond Back Moth and bioassays were also done to assess its safety to silkworm. Ten native isolates from Maharastra were bioassayed and these isolates revealed variations in the mortality.
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Since 2000 a new invasive pest is wreaking havoc on eucalyptus plantations throughout the world. First reported from northern and eastern Africa, the Middle East and Mediterranean countries, the pest has expanded its range like wild fire... more
Since 2000 a new invasive pest is wreaking havoc on eucalyptus plantations throughout the world. First reported from northern and eastern Africa, the Middle East and Mediterranean countries, the pest has expanded its range like wild fire in every continent. Presumed to have originated from Australia, the pest was subsequently identified as a gall wasp, Leptocybe invasa Fisher & La Salle (Hymenoptera: Eulophidae) (Mendel et al., 2004). In India it was first noticed in 2001 at Mandya district in Karnataka and later in 2002 at Marakkanam in Villupuram district of Tamil Nadu. It was also reported from Andhra Pradesh, Kerala, Pondicherry, Gujarat, Madhya Pradesh, Uttar Pradesh, Maharashtra, Goa, and Delhi (Kumar et al., 2007). Adult female measures 1.1 to 1.4 mm and lays eggs inside tender leaves and stem. Larvae after hatching out of eggs remain in a cavity formed within the plant tissues and feed on the tissues which results in formation of galls.
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Commercial eucalyptus plantations are important global assets providing wood and wood fiber products to modern societies and offer a wide range of social, environmental and economic benefits to millions of people. Eucalyptus meets... more
Commercial eucalyptus plantations are important global assets providing wood and wood fiber products to modern societies and offer a wide range of social, environmental and economic benefits to millions of people. Eucalyptus meets requirements of people, industries and has helped to reduce pressure on natural forests. More than 16 million hectares of eucalyptus is planted around the world for various purposes including pulp for paper manufacture, solid wood and structural timbers and as woodlots for fuel.
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Rhizobacterial isolates were investigated for biocontrol efficacy against bhendi yellow vein mosaic virus (BYVMV) in bhendi plants. Bioformulations of rhizobacteria applied to seed, soil and foliage significantly reduced BYVMV, with a... more
Rhizobacterial isolates were investigated for biocontrol efficacy against bhendi yellow vein mosaic virus (BYVMV) in bhendi plants. Bioformulations of rhizobacteria applied to seed, soil and foliage significantly reduced BYVMV, with a concomitant increase in plant growth and fruit yields under glasshouse condition. Of all the rhizobacterial isolates evaluated, fluorescent Pseudomonas 218 (1) was the most effective strain. It reduced the incidence of BYVMV to the maximum extent (up to 86.6 per cent), through induced systemic resistance by triggering defense molecules. Biosynthesis of peroxidase and PALase were improved by 79 and 47 percent respectively over the diseased control.
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A field experiment was laid out in a randomized complete block design with three replications on vertisol at Main Agricultural Research Station (MARS), University of Agricultural Sciences (UAS), Dharwad during the rainfed seasons of 2007... more
A field experiment was laid out in a randomized complete block design with three replications on vertisol at Main Agricultural Research Station (MARS), University of Agricultural Sciences (UAS), Dharwad during the rainfed seasons of 2007 and 2008 to assess the performance of Bt and non-Bt cotton genotypes under leaf reddening situation. The experiment consisted of ten treatments (cotton hybrids) viz., T1-Bunny (BG I) Bt, T2-Bunny non-Bt, T3-RCH-368 (BG I) Bt, T4-RCH- 368 non-Bt, T5-JK Durga (BG I) Bt, T6-JK Durga non-Bt, T7-Neeraja (BG II) Bt, T8-Neeraja non-Bt, T9-DCH-32 non-Bt hybrid and T10-Sahana non-Bt variety were sown at 90 cm x 60 cm spacing. Results indicated that, Neeraja (BG II) Bt produced significantly higher seed cotton yield (2483 kg/ha) as compared to the other genotypes. The yield levels of Bt and non-Bt cotton genotypes under study were in the range between 2483 kg/ha and 1131 kg/ha. The lowest seed cotton yield was observed in RCH-368 non-Bt (1131 kg/ha). Mean red...
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Among the six oils screened, sesamum, honge and linseed oils greatly synergised fenvalerate. Honge oil alone at higher dosage (0.3 and 0.4%) showed significant insecticidal activity. Sesamum oil (0.2 per cent) recorded highest larval... more
Among the six oils screened, sesamum, honge and linseed oils greatly synergised fenvalerate. Honge oil alone at higher dosage (0.3 and 0.4%) showed significant insecticidal activity. Sesamum oil (0.2 per cent) recorded highest larval mortality of 81.50 and 99.99 per cent at 24 and 48 h, respectively and was significantly superior to other oils. Larval mortality with honge and sesamum oils in combination with synthetic pyrethroids increased with the increase in dosage and interval of observation. At the shortest interval of 24 h, honge oil and sesamum oil at 0.2 per cent synergised all the pyrethroids tested. Both sesamum and honge oils at 0.2 per cent can be utilized to prolong the efficacy of pyrethroids. Under field conditions these combinations showed varying degrees of synergism, which increased up to three days and declined there after indicating instability of these combinations.
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Utilization of native parasitoids viz. Megastigmus dharwadicus Narendran and Vastrad (Hymenoptera: Torymidae) and Aprostocetus gala Walker (Hymenoptera: Eulophidae) for biological control of eucalyptus gall wasp, Leptocybe invasa Fisher... more
Utilization of native parasitoids viz. Megastigmus dharwadicus Narendran and Vastrad (Hymenoptera: Torymidae) and Aprostocetus gala Walker (Hymenoptera: Eulophidae) for biological control of eucalyptus gall wasp, Leptocybe invasa Fisher and LaSalle (Hymenoptera: Eulophidae) is reported. Two native parasitoids multiplied in the greenhouse were released in a severely affected eucalyptus plantation spread over an area of 1000 ha. A total of 14,000 heavily parasitized galled seedlings, 1400 M. dharwadicus and 300 A. gala were distributed over a period of six months. The per cent parasitization by these native parasitoids was ascertained before distribution of galled seedlings. Though there was a gradual increase in per cent parasitization, the reduction in gall incidence was not evident up to three months. However, drastic reduction in gall incidence and pest emergence accompanied by very high per cent parasitization was evident within eight months. Post release evaluation conducted dur...
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Cotton is being cultivated in 70 countries of the world with a total coverage of 32.30 m ha (Anon., 201 1b). Area wise, India ranks first in global scenario (about 33% of the world cotton area). However , in production it ranks second... more
Cotton is being cultivated in 70 countries of the world with a total coverage of 32.30 m ha (Anon., 201 1b). Area wise, India ranks first in global scenario (about 33% of the world cotton area). However , in production it ranks second next to China. In India, cotton was cultivated in an area of 11.16 m ha with a production of 31.20 million bales of seed cotton during 2010-11. Average productivity of cotton in India is 494 kg lint/ha, which is low when compared to world average of 725 kg lint/ha (Anon., 2011a).The important cotton growing states in India are Maharashtra, Gujarat, Andhra Pradesh, Madhya Pradesh, Punjab, Haryana, Karnataka, Rajasthan and Tamil Nadu. In India, Bt cotton since its release in 2002 by Genetic Engineering Approval Committee (GEAC) replaced more and more conventional cotton area. There was an exponential increase in Bt cotton area from 29,000 ha in 2002 to 11.16 m ha in 2010 accounting for a staggering 92% of the total cotton area in India. It is estimated t...
Sesame is attacked by numerous pests which reduce its yield both in quality and quantity. To study the pest complex of sesame and their natural enemies, roving survey and fixed plot survey was conducted in North Karnataka and in... more
Sesame is attacked by numerous pests which reduce its yield both in quality and quantity. To study the pest complex of sesame and their natural enemies, roving survey and fixed plot survey was conducted in North Karnataka and in Agricultural Entomology field, MARS, UAS, Dharwad during Kharif -2011 and summer-2012. Altogether 55 species of arthropods were found to be associated with sesame, out of which 30 species were identified as pest and 25 as natural enemies including 2 strains of entomopathogen. Among the different insect pests recorded, highest number of species was obtained in Heteroptera followed by Homoptera, Lepidoptera, Coleoptera and Thysanoptera. During Kharif 2011, 25 species were recorded however in summer 2012, only 22 species were recorded and their relative abundance was 53.19 and 46.81 per cent respectively. Out of 30 species recorded, Acherontia styx, Spilarctia oblique, Nezara viridula, Dolycoris indicus, Orosius albicinctus and Bemisia tabaci were the major pes...
A field experiment was conducted at the University of Agricultural Sciences, Dharwad, Karnataka, during Kharif 2007 to study the effect of vermicompost and vermiwash on the activity defoliator pests, pod borer and yield attributes of... more
A field experiment was conducted at the University of Agricultural Sciences, Dharwad, Karnataka, during Kharif 2007 to study the effect of vermicompost and vermiwash on the activity defoliator pests, pod borer and yield attributes of soybean. The results indicated that application of vermicompost @ (2 t/ha) and split application of vermicompost (2 t/ha + four vermiwash (1:3) sprays were effective in reducing the incidence of defoliators and pod borer, being comparable to RPP. Significantly highest seed yield was registered in the treatments receiving vermicompost @ 3 t/ha + four sprays of vermiwash (1:5) (30.00 q/ha) and vermicompost @ 1 t/ha + four sprays of vermiwash (1:1) (25.83 q/ha) which were on par with each other, were comparable to RPP (30.80q/ha). Untreated crop yielded significantly lowest yield at 10.58 q/ha.
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Investigations were carried out to assess the efficacy of Sikkim Bacillus thuringiensis isolates against lepidopteran insects viz., Cabbage leaf webber, Diamond Back Moth and bioassay were also done to assess the safety nature of Bt to... more
Investigations were carried out to assess the efficacy of Sikkim Bacillus thuringiensis isolates against lepidopteran insects viz., Cabbage leaf webber, Diamond Back Moth and bioassay were also done to assess the safety nature of Bt to silkworm. Bacillus thuringiensis isolates of Sikkim (Thirty five isolates) were assessed. Among these isolates mortality of each isolate was varied from insect to insect. The mortality of 86.67% was registered by the isolates 1554/b, 1526B/b and 1598d against Cabbage leaf webber. The isolates 6a4, 1598a, 1526B/b, 1622A/a and 1642A/a recorded maximum (93.33%) mortality against Diamond Back Moth. Whereas, 93.33 and 90.00 per cent mortality was recorded in 1620b and 1598d, respectively, against silkworm.
Fifty rhizobacterial isolates were screened against Tomato leaf curl Virus (ToLCV) disease under glasshouse condition. Application of rhizobacteria based bioformulations to seed, soil and foliage significantly reduced the disease severity... more
Fifty rhizobacterial isolates were screened against Tomato leaf curl Virus (ToLCV) disease under glasshouse condition. Application of rhizobacteria based bioformulations to seed, soil and foliage significantly reduced the disease severity of ToLCV from 28.58 to 85.72% with Pseudomonas sp 206 (4) and Pseudomonas sp. B-15. All isolates induced systemic resistance to the disease. The plants inoculated with Pseudomonas sp. 206 (4) recorded highest phenolic content, and peroxidase, polyphenol oxidase, chitinase and PALase activities with reduction in insect population. Semi quantitative PCR analysis revealed lower viral load in plants inoculated with these isolates. Electron microscopic examination of ToLCV revealed the presence of isometric and pentagonal Gemini virus, (20 × 30 nm to 24 × 30 nm). Treatment with fluorescent Pseudomonas 206(4) recorded maximum plant height, total biomass and chlorophyll content.
An experiment was undertaken at the Department of Agricultural Entomology, University of Agricultural Science, Dharwad. It involved bioassay of indoxacarb, flubendiamide, chlorpyrifos and Bacillus thuringiensis subsp.kurstaki (Btk)... more
An experiment was undertaken at the Department of Agricultural Entomology, University of Agricultural Science, Dharwad. It involved bioassay of indoxacarb, flubendiamide, chlorpyrifos and Bacillus thuringiensis subsp.kurstaki (Btk) against Spodoptera litura (Fab) and Helicovepa armigera (Hubner) populations collected from different host crops. S. litura was collected from cabbage, soybean and groundnut while H. armigera from tomato, chickpea and cotton. S. litura collected from groundnut was highly susceptible with lower LC50 values against the insecticides viz., indoxacarb (15.91 ppm), flubendiamide (11.69), chlorpyrifos (50.36) and B. thuringiensis subsp. kurstaki. S. litura collected from cabbage was found to be more resistant with higher LC50 values against all of the insecticides. Similarly, H. armigera larvae collected from cotton was more susceptible with lower LC50 values against indoxacarb, flubendiamide and chlorpyrifos, whereas the larvae collected from tomato showed resi...
The recent outbreak of the invasive gall wasp, Leptocybe invasa Fisher & La Salle has threatened the productivity of the existing eucalyptus plantations and has become a constraint in the expansion of the plantations throughout India. In... more
The recent outbreak of the invasive gall wasp, Leptocybe invasa Fisher & La Salle has threatened the productivity of the existing eucalyptus plantations and has become a constraint in the expansion of the plantations throughout India. In the present study among the different coloured sticky traps evaluated, yellow trap was most effective in trapping the pest (146.83/trap) followed by green (67.33), white (66.33), blue (49.08) and red (48.92) which were on par with each other. The results indicated that yellow sticky traps can be used both for monitoring the pest in general and mass trapping it in nursery and under protected cultivation. Among the three sticky materials used with or without eucalyptus oil, insect gum with and without oil trapped 192.00 and 169.25 wasps respectively followed by petroleum jelly with oil (122.25/trap). Automobile grease (with or without eucalyptus oil) trapped the lowest number of wasps (54.25 to 56.25/trap). Among the different shapes evaluated, flat t...
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An investigation was carried out to assess the bio-efficacy and cry profile of hundred native Bacillus thuringiensis isolates against Cabbage Leaf Webber viz., Crocidolomia binotalis and Spodoptera litura at the Department of Entomology,... more
An investigation was carried out to assess the bio-efficacy and cry profile of hundred native Bacillus thuringiensis isolates against Cabbage Leaf Webber viz., Crocidolomia binotalis and Spodoptera litura at the Department of Entomology, University of Agricultural Sciences, Dharwad. Among the hundred native isolates used, isolates DBT-763, DBT-787, DBT-754 and DBT-2370 reported 86.67 per cent mortality against Crocidolomia binotalis and DBT-772 showed 73.33 per cent mortality against Spodoptera litura . Lepidopteron specific cry genes viz., cry1, cry2, cry8, and cry9 genes amplified in native isolates viz ., DBT-2367, DBT-2366, DBT-2299, DBT-2299, respectively and none of the studied native isolates shown amplification for the cry20 gene.
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Roving survey was conducted during 2010-11 to assess impact of native parasitoids on eucalyptus gall wasp in Belgaum, Dharwad, Haveri, Davangere, Chitradurga, Tumkur and Bengaluru Rural districts of Karnataka, India. It was observed that... more
Roving survey was conducted during 2010-11 to assess impact of native parasitoids on eucalyptus gall wasp in Belgaum, Dharwad, Haveri, Davangere, Chitradurga, Tumkur and Bengaluru Rural districts of Karnataka, India. It was observed that the gall incidence declined drastically since its outbreak in 2007 due to the activity of native parasitoids. Activity of native parasitoids was more in southern districts. Among the native parasitoids Megastigmus dharwadicus Narendran et al was the most dominant. The eucalyptus gall wasp which had become a production constraint during 2007 threatening the productivity of paper and pulp industry is efficiently kept under check by the native parasitiods.
Investigations were carried out to assess the efficacy of crude protein of some of Bacillus thuringiensis isolates against lepidopteran pest viz., cabbage leaf webber (CLW) Crocidolmia binotalis Zel. mortality. The native isolate 1526B/b... more
Investigations were carried out to assess the efficacy of crude protein of some of Bacillus thuringiensis isolates against lepidopteran pest viz., cabbage leaf webber (CLW) Crocidolmia binotalis Zel. mortality. The native isolate 1526B/b recorded highly virulent (LC 50 = 682.420 ppm) where as M-126 recorded lowest virulent (LC 50 = 6572.822 ppm). To identify the spectrum of insecticidal genes in the native B. thuringiensis isolates, the polymerase chain reaction (PCR) was carried out and the results show that none of the isolates amplified cry3, 4 and 18 genes.
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Bioefficacy of 100 native Bacillus thuringiensis isolates were evaluated. Isolates DBT-772 and DBT-338 recorded 100 per cent mortality against 3rdinstar larvae of Plutella xylostella and molecular characterization of lepidopteran specific... more
Bioefficacy of 100 native Bacillus thuringiensis isolates were evaluated. Isolates DBT-772 and DBT-338 recorded 100 per cent mortality against 3rdinstar larvae of Plutella xylostella and molecular characterization of lepidopteran specific cry1, cry2, cry8, cry9 and cry20 genes reviled that cry1 as the dominant gene (54.7%) and none of the eleven isolates recorded the presence of cry20 gene. Consortium of four isolates DBT-787, DBT-338, DBT-772 and DBT-2370 recorded synergistic effect on DBM larvae.
Thiodicarb, lufenuron, Spinosad and Bacillus rhurengiensis (Biobit) emerged as the most promising insecticides for managing field populations of DBM resistant to conventional insecticides. Reduction of larval population in plots treated... more
Thiodicarb, lufenuron, Spinosad and Bacillus rhurengiensis (Biobit) emerged as the most promising insecticides for managing field populations of DBM resistant to conventional insecticides. Reduction of larval population in plots treated with these chemicals ranged from 57.13 to 99.99 per cent. Incidentally efficacy of these products resulted in higher yields during two field trials. Fipronil, carbosulfan, indoxacarb and diafenthiuron also performed well compared to the standard check (malathion) which recorded lowest reduction (30.63 to 64.18%) in larval population as well as lowest yield (498.40 and 542.70 q ha") during both trials. Due to diverse modes of action these chemicals could be excellent choices in a rotational strategy aimed at prolonging their efficacy by delaying the onset of resistance development.