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201113
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Subject: Agricultural Entomology × End date: 2011 × Start date: 2011 ×
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    ThesisItemOpen Access
    Biology, Seasonal Incidence and Management of Acherontia styx Westwood On Sesame
    (UAS, Dharwad, 2011) Kumar Kanaburgi; R.R. Patil
    The sphingid, Acherontia styx Westwood has assumed a major pest status on Sesame in North Karnataka. The investigations were conducted on biology, seasonal incidence and management of A.styx Westw. on sesame during 2010-11. It was interesting to record that, during off season (Nov-Feb) the pest survived on weed host, Clerodendrum phlomidis completing one generation. A. styx is being recorded for the first time on C. phlomidis. The development of egg, larva, pre-pupa and pupal periods occupied 6.0±0.91, 19.55±0.23, 5.70±0.69 and 19.70±1.65 days on S. indicum and 6.0±0.67, 19.80±1.23, 6.50±0.85 and 20.3±2.99 days on C. phlomidis. In the first fortnight of July, the initial population of sphingid was low with an average of 4.0 larvae per 10 plants with 30% defoliation of S. indicum. The peak population was in August with 5.33 and 5.66 larvae per 10 plants with 38 and 42 per cent defoliation during first and second fortnight, respectively. Among the different chemical insecticides, flubendiamide 480 SC was superior to rest of the chemicals followed by spinosad 48 SL, emamectin benzoate 5 SG, deltamethrin 2.8 EC and indoxacarb 14.5 SC. Among the ovicides, methomyl was effective. The neem based insecticides, nimbicidine was effective followed by NSKE 5%. Use of Trichogramma chilonis in three different doses Viz., T.chilonis @75000, 150000 and 225000 revealed effectiveness of T. chilonis @ 1,50,000/ha with egg parasitization of 72%. Maximum grain yield was obtained with flubendiamide 480 SC (5.92 q/ha). Among neem based insecticides, nimbicidine recorded higher grain yield (2.91 q/ha), while NSKE 5% had minimum (2.48 q/ha). Grain yield of 3.97 q/ha was obtained with T. chilonis @ 1,50,000/ha. Benefit:Cost ratio of different chemicals revealed higher B:C ratio (3.62) with flubendiamide 480 SC compared to other chemicals. NSKE 5% treatment recorded only B:C ratio of 2.00.
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    ThesisItemOpen Access
    Bioefficacy and Molecular characterization of Native Bacillus thuringiesis (Berliner) Isolates Against Lepidopteran Pests of Cabbage
    (UAS, Dharwad, 2011) Prabhakar A.; P.S. Hugar
    The bio-efficacy of one hundred native Bacillus thuringiensis isolates was assessed against five day old lepidopteran insects (Spodoptera litura Fab., Crocidolomia binotalis Z. and Plutella xylostella L.). Molecular characterization and crude protein assay of eleven efficient isolates was done to identify the presence of insecticidal genes and the efficacy to target insects respectively. Based on the bioefficacy and the presence of the cry genes, consortia were developed against P. xylostella. Out of the 100 isolates tested Tx-232 and 531/a recorded cent per cent mortality against P. xylostella, 90 per cent mortality was shown by Tx-379 and 86.67 per cent mortality by Tx-201, AIM-72(1) and AIM-72 (2). Among isolates, Tx-201, Tx-29, Tx-379, AIM-72(2) showed 86.67 per cent and AIM-72(1), Tx-202 showed 80.00 per cent mortality against C. binotalis. Tx-232 registered 73.33 per cent and Tx- 202 recorded 66.67 per cent mortality of S. litura larvae. Out of eleven native Bt isolates tested for lepidopteran specific cry genes, cry1 gene was amplified in six isolates, cry2 amplified in four isolates, cry8 and cry9 was amplified in two isolates. However cry20 was not present in any of the eleven isolates. All the selected eleven isolates performed well against P. xylostella, C. binotalis but not against S. litura in crude protein assay. The consortium of two [531/a + Tx 232 and 531/a + AIM-72(2)] isolates recorded cent per cent mortality, three isolates combinations [Tx 379 + 531/a + Tx 232 and 531/a + Tx 232 + AIM-72(2) and four isolates combination [531/a + Tx 232 + AIM-72(2) + Tx 379] showed cent per cent mortality with quicker knock down effect against P. xylostella compared to the reference.
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    ThesisItemOpen Access
    Functional Dimensions of Mirid Bug, Creontiades biseratense (Distant) (Miridae : Hemiptera) Population Dynamics in Bt Cotton
    (UAS, Dharwad, 2011) Manohar V. Shyadaguppi; Shashikant S. Udikeri
    A season long fixed plot survey was conducted across 13 locations in Haveri district. On Kanaka Bt BG-II, the average population across the district was 128.3 + 18.2 mirids/100 squares with highest (284.5 + 60.2) in November first fortnight and least (14.5 + 3.4) in February. The population was high in Rattihalli (190.4 + 115.6) followed by Aladakatti (164.5 + 108.3) and least in Bisanahalli (87.8 + 70.2). Mirid menance was severe in Hirekerur and Haveri and least in Shiggaon taluk. There was significant positive correlation noticed between mirid incidence and squares on cotton plants. Mirid bug population had negative association with maximum and minimum temperature and positive association with morning and evening relative humidity and rainfall. The important predators viz., Spiders Chrysoperla carnea, Coccinellids and Nabis spp. showed positive correlation with mirid bug population. The species of mirid bug found to infest the cultivated crops viz., pigeonpea, maize, sunflower, safflower, sorghum, amaranths and castor. A total of 65.48 and 28.90 early and late instar mirid bugs were consumed by single C. carnea grub during its developmental period. However, third instar C. carnea was predominant predator with daily consumption of 8.04 and 3.40 mirid bug early and late instar nymphs. The feeding potentiality of Lynx spider, Oxyopes biramanicus was 5.39 nymphs and 2.36 adult mirid bugs per day. The EIL and ETL worked out appeared to be 6.50 and 5.00 nymphs/plant, respectively. Based on molecular study, it was evident that C. biseratense (Distant) occurring in different locations viz., Dharwad, Belgaum, Haveri, Raichur and Gulbarga on Bt cotton, pigeonpea and maize belonged to same species despite colour morphs.
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    ThesisItemOpen Access
    Biology and Management of Rice Earhead Bug, Leptocorisa oratorius, Fabricius (Hemiptera : Alydidae) in Rainfed Ecosystem of Uttara Kannada District
    (UAS, Dharwad, 2011) Basavaraj Ashokappa H.T.; S.T. Prabhu
    Studies on bioecology and management of rice earhead bug, Leptocorisa oratorius, Fabricius (Hemiptera: Alydidae) were undertaken during kharif, 2010 in rainfed ecosystem of Uttara Kannada district. Uttara Kannada district represents three distinct rice ecosystems, namely; ’upghat’ drill sown paddy, ’upghat’ transplanted paddy and coastal transplanted paddy. The roving survey taken up in these ecosystems revealed the two species belonging to the genus Leptocorisa, viz., L. oratorius, and L. lepida. Assuming that all rice earhead bugs were L. oratorius, it was confirmed by observing the characteristic black ventrolateral spots on the abdominal segments of this species. Among the two species L. oratorius was of high abundance and noticed in almost all places of surveyed. The highest incidence of rice earhead bug was recorded at reproductive stage of crop during kharif season than rabi. The maximum population of 3.04 nymphs and adults per hill was recorded, during October (kharif-2010) in Mundgod and least in Sirsi (1.97/hill). Whereas, in rabi (2011) maximum population of 2.04 nymphs and adults per hill was recorded during May in Mundgod and least in Kumta (1.08/hill). The preadatory spiders, coccinellids, ground beetles, dragonflies, damselflies, bugs and roberflies were recorded during both the seasons. Seven alternate hosts of rice earhead bug were observed during survey which included Echinocloa crusagalli (L.), Echinocloa colonum (Link.), Eleusina indica (L.) Gaertn, Digitaria sanguinalis (L.), Cyperes rotundus (L.), Cyperes iria (L.) and Brachiria mutica (Stapf.). Among the various botanicals, entomopathogenic fungi and synthetic insecticides evaluated for the management of rice earhead bug, imidacloprid 17.8 SL @ 0.25 ml/l was found very effective in reducing rice bug population and was at par with thiamethoxam 25 WG @ 0.3 g/l and malathion 5D @ 20 kg/ha. Next best treatments included azadirachtin 3000 ppm @ 3 ml/l and Acorus calamus aqueous rhizome extract @ 10%.
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    ThesisItemOpen Access
    Comparative Performance of Indigenous Bee Attractants in Bt and Non-Bt Cotton Hybrids
    (UAS, Dharwad, 2011) Vinayak Pise; Shashidhar Viraktamath
    Comparative studies on pollinator fauna, foraging activity of honey bees and effect of indigenous bee attractants on bee visitation and yield parameters of Bt and non-Bt cotton were made during Kharif season of 2010 at Dharwad. Among 18 species of pollinators, Apis dorsata F., was the most dominant (29.83 %) followed by A. cerana F. (25.21 %) and A. florea F. (22.54 %). Activity of honey bees was observed throughout the day with a peak at 1200 h in both Bt and non-Bt cotton. No significant difference in the activity was observed between Bt and non-Bt cotton hybrids. Indigenous bee attractants (Citral E, Citral Z, Fagara budrunga, Swertia densifolia) were equally effective in attracting significantly more number of bees (2.25 to 3.25 and 2.17 to 3.17 bees /10m2/5 min in Bt and non-Bt cotton, respectively) which was as good as the Fruit boost, a commercial bee attractant. However, there was no significant difference among Bt and non-Bt cotton hybrids with respect to bee visitation. Bee attractants enhanced the yield parameters viz, good opened bolls (8.37 to 9.56 and 7.18 to 8.25 % in Bt and non-Bt cotton, respectively), seeds per boll (10.82 to 21.89 and 10.67 to 16.64%), lint yield (5.80 to 7.83% and 4.85 to 5.13), seed yield (11.60 to 14.02 and 7.63 to 11.84%) and kapas yield (10.39 to 15.05 and 8.56 to 12.65%). At the same time there was a decline in the bad opened bolls (30.82 to 28.53 and 22.22 to 16.66 %) both in Bt and non-Bt cotton hybrids. The extent of increase in the total yield due to spray of indigenous bee attractants was more or less similar both in Bt (10.39 to 15.05 %) and non-Bt cotton (8.56 to12.65 %) hybrids.
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    ThesisItemOpen Access
    Studies on Insect Pests and Their Predators in Upland Rice Ecosystem
    (UAS, Dharwad, 2011) Girish V.P.; M.G. Hegde
    A study was conducted on the insect pests and predators of upland rice ecosystem at ARS (Paddy), Mugad during kharif 2010. The blue beetle, leafhopper and horned caterpillar appeared in the vegetative phase of the crop and their population was significantly high in drill sown rice, compared to transplanted and aerobic rice. Leaf folder incidence was recorded throughout the season under all the planting methods. Drill sown rice crop supported significantly higher population when compared to aerobic rice. A meager population of grasshopper and earhead bug was recorded across the method without any statistical difference. Yellow stem borer population was significantly high in aerobic method during reproductive phase of the crop. The coccinellids, predatory spiders, ground beetle and odonata population were recorded throughout the season in all the three rice planting methods. The predatory spiders population was significantly high in drill sown and transplanted rice, compared to aerobic crop. The coccinellid, ground beetle and odonata were found throughout the season without any distinct population pattern across the planting methods. Among the newer insecticides and botanical evaluated against leaf folder, emamectin benzoate 5 SG @ 0.25 g/l, spinosad 45 SC @ 0.2ml/l and flubendiamide 480SC @ 0.2 ml/l recorded lowest per cent leaf damage. Similarly, emamectin benzoate, bifenthrin, profenophos, chlorfenpyr and thiocloprid were more toxic to the predatory spiders. The highest grain yield, net profit and B:C ratio was recorded in emamectin benzoate treatment. Among the rice varieties screened against rice leaf folder, Dambarsali, Ratansagar, Champakali, M-18, J-192, Kari Kantiga, Hybrid 258- 1, Kannanur local, Chitiga, MGD-103, MGD-105, MTU-1010, Amrut, MAS-26, ARB-6,and Rajmani showed resistant reaction. All the resistant cultivars showed hairiness as against smooth surface in moderately susceptible and susceptible varieties.
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    ThesisItemOpen Access
    Biophysical and Biochemical Basis of induced Resistance Against Soybean Pests Nourished with Organics
    (UAS, Dharwad, 2011) Jinsa Nazeem; R.S. Giraddi
    The studies on the biophysical and biochemical basis of induced resistance as influenced by organic, inorganic, integrated nutrient management (INM) and natural farming practices in soybean against defoliators and pod borer were undertaken during kharif 2010-11 at the Main Agricultural Research Station (MARS), University of Agricultural Sciences, Dharwad. The results indicated that least larval population of Spodoptera litura (Fab.) and Thysanoplusia orichalcea (Fab.) (0.08 and 2.50 l/m row, respectively at 6 WAS) and minimum per cent pod damage by Cydia ptychora (Meyk.) (3.32%) were recorded in the treatment that received 100 per cent organics followed by 75% organics (2.51, 0.00 l/m row, 3.37%, respectively). The RPP recorded higher larval population (0.17and 3.28 l/m.row, respectively at 6 WAS) and pod damage (5.86%) followed by fully inorganic, natural farming, INM which were on par with each other. The studies on biophysical factors at 45 DAS revealed lower leaf succulency (78.28%) and higher leaf thickness (5.69 mg/cm2) imparted induced resistance against pest infestation in plants receiving organic nourishment compared to inorganic (82.49% and 4.86 mg/cm2 respectively). The biochemical constituent, phenol recorded higher amount (0.61 mg/g fr.wt-1 at 60 DAS) in plants nourished with organics resulting into lower pest incidence owing to induced resistance. The lower amounts of sugars, free amino acids, soluble proteins and prolines also imparted resistance to the plants receiving organics whereas higher quantities recorded in inorganic treatments resulted in susceptibility to pests. Morphological characters like plant height, number of leaves, leaf area index, number of pods, number of nodules etc. were enhanced in organically nourished plants. Also, plants under organic nutrition recorded higher nodule dry weight, 100-seed weight, seed weight/plant and grain yield (2994.25 kg/ha) which were comparable to RPP (3375.75 kg/ha). Microbial activity especially of heterotrophs in soil receiving organics was higher which induced the resistance capacity of plants through the production of antibiotics, psederophores etc., than in other treatments.
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    ThesisItemOpen Access
    Effect of Imidacloprid and Thiamethoxam Seed Treatment on Storability and Sucking Pests in Sunflower
    (UAS, Dharwad, 2011) Asha V. Kencharaddi; R.A. Balikai
    Both laboratory and field experiments were carried out at the Agriculture College, Dharwad during 2009-10 to study the effect of imidacloprid and thiamethoxam seed treatments on storability and incidence of early sucking pests in sunflower hybrid KBSH-41. Laboratory studies indicated that seeds treated with imidacloprid and thiamethoxam seeds could be stored in polythene bag of more than 700 gauges up to ten months without significant reduction in the seed quality. Field studies revealed that the reduction in thrips population was highest in treated check (imidacloprid 200 SL @ 0.25 ml/l) as compared to other treatments. The treated seeds could be stored for one month without loosing any efficacy against thrips. Lowest leaf hopper and whitefly incidence was recorded in seeds treated with imidacloprid 600 FS @ 10 ml/kg seeds followed by imidacloprid 70 WS @ 5 g/kg seeds, thiamethoxam 70 WS @ 5 g/kg seeds and thiamethoxam 35 FS @ 10 ml/kg seeds. Both leaf hopper and whitefly were under control up to 45 days and treated seeds could be stored for two and three months, respectively without loosing any efficacy. The honey bee visitation to sunflower field and head diameter were unaffected by seed treatment with insecticides and different storage periods. Significantly highest gross and net returns were obtained in imidacloprid 600 FS @ 10 ml/kg seeds followed by thiamethoxam 70 WS @ 5 g/kg of seeds and the latter treatment was on par with thiamethoxam 35 FS @ 10 ml/kg of seeds and imidacloprid 70 WS @ 5 g /kg seeds. Seeds stored for one month recorded significantly higher gross returns and net profit as compared to any of the other storage periods. Higher cost benefit ratio (2.63) was recorded from imidacloprid 600 FS @ 10 ml/kg seeds treatment followed by imidacloprid 70 WS @ 5 g/kg seeds.
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    ThesisItemOpen Access
    Biology and Management of Rice Gall Midge, Orseolia oryzae (Wood-Mason)
    (UAS, Dharwad, 2011) Archana D.; Javaregowda
    Biology of rice gall midge Orseolia oryzae (Wood-Mason) was studied in detail during August to October under laboratory conditions at ARS, Sirsi. Egg, maggot and pupal periods occupied 2.50±1.41, 9.00±0.71 and 4.00±0.71 days, respectively. Average fecundity was 96.5±14.85 eggs/female and total life cycle occupied 17.50±3.54 days. Among the rice varieties screened at ARS, Sirsi, forty three were moderately susceptible, nineteen were moderately resistant, ten were susceptible and remaining eight proved to be highly resistant. None of the tested varieties were neither resistant nor highly susceptible at 30 and 50 DAT compared to susceptible check Jaya (21.29% SS). Similarly, among the 48 hybrids screened, forty one were susceptible, two were highly susceptible and remaining five were highly resistant. None of the hybrids could be categorized under resistant, moderately resistant and moderately susceptible group. Among thirty five rice varieties screened at ZARS, Brahmavara, four rice genotypes proved highly resistant (0% SS); thirty one genotypes reacted highly susceptible (>25% SS) but none of the genotypes were resistant (<1% SS); moderately resistant (1-5% SS); moderately susceptible (6-10% SS) and susceptible (11-25% SS) at 50 DAT. Fipronil 40 WG @ 1 g/l was on par with carbofuran 3G @ 10 kg/ha for incidence of silver shoot (8.06 and 8.81), grain (65.98 and 64.05) yield and straw (69.73 and 67.01 q/ha) yield followed by profenophs 50 EC @ 2 ml/l. Among the botanicals evaluated, soap nut extract + neem oil @ 2.5% recorded least per cent silver shoot (17.07) resulting in increased grain (51.19 q/ha) and straw yield (53.15 q/ha) followed by Randia spinosa @ 20 kg/ha, Gnidia glauca leaf extract @ 5% and nimbecidine @ 3 ml/l. Higher C:B ratio of 1:3.04 was obtained from carbofuran 3G @ 10 kg/ha followed by profenophos 20 EC @ 2 ml/l (1:2.77) and fipronil 40 WG @ 1.0 g/l (1:2.52).