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201812
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Subject: Entomology × End date: 2018 × Start date: 2018 ×
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    ThesisItemOpen Access
    Evaluation of Some Insecticides for the Control of Brahmina coriacea (Hope) in Himachal Pradesh
    (CSKHPKV, Palampur, 2018-09-29) Koranga, Radha; Chandel, R. S.
    The bioassay study of six insecticides viz. chlorantraniliprole, bifenthrin, clothianidin, thiamethoxam, imidacloprid and chlorpyriphos was conducted against grubs and adults of Brahmina coriacea (Hope). Against grubs, these chemicals were evaluated through dip treatment. The LC50 values of chlorantraniliprole for I - III instar grubs of B. coriacea were calculated to be 70.65, 213.30 and 226.1 ppm, while in case of bifenthrin, the LC50 values were determined as 100.2, 259.90 and 337.10 ppm. The LC50 values of clothianidin for I - III instar grubs were calculated to be 139.51, 266.12 and 348.30 ppm. Imidacloprid produced 50 per cent kill (LC50) at a concentration of 156.12, 415.58 and 622.04 ppm in I - III instar grubs, and for thiamethoxam the respective LC50 values were computed to be 205.89, 477.31 and 626.67 ppm. Chlorpyriphos was found to be least toxic among tested chemicals, and it produced 50 per cent kill of I - III instar grubs of B. coriacea at a concentration of 222.60, 506.92 and 556.72 ppm, respectively. These six soil insecticides were also evaluated against adults of B. coriacea by releasing the beetles in soil, contaminated with different insecticides. Among these, chlorantraniliprole was found to be highly effective. The LC50 value of chlorantraniliprole was calculated to be 0.022 g a.i./kg soil. In bifenthrin, and clothianidin the LC50 values were determined to be 0.028 g a.i./kg soil and 0.034 g a.i./kg soil. Thiamethoxam produced 50 per cent kill of beetles at a dose of 0.047 g a.i./kg soil. The LC50 values of chlorpyriphos and imidaclprid for adults of B. coriacea were calculated to be 0.058 g a.i./kg soil and 0.066 g a.i./kg soil. The order of toxicity of tested soil insecticides to beetles was chlorantraniliprole > bifenthrin > clothianidin > thiamethoxam > chlorpyriphos > imidacloprid. All tested soil insecticides at low doses (1.20×10-4 - 0.15×10-4 g a.i./kg soil) induced reduction in egg laying by females beetles of B. coriacea. The egg production decreased in a dose dependent manner in all the treatments. The average number of eggs laid in different treatments ranged from 28.4 - 44.8 eggs/3 females. Maximum curtailment in egg laying was observed in bifenthrin (82.06 %), followed by chlorpyriphos (79.28 %). Against beetles of B. coriacea, dimethoate, indoxacarb, flubendiamide, spinosad, fenazaquin, mancozeb and dodine were tested by leaf dip and topical application methods. In leaf dip method, the LC50 values of dimethoate, indoxacarb, flubendiamide, spinosad and fenazaquin were calculated to be 8.41, 165.20, 186.66, 246.09 and 460.60 ppm, respectively. The order of toxicity was dimethoate > indoxacarb > flubendiamide > spinosad > fenazaquin. Among fungicides, mancozeb and dodine were tested. Mancozeb produced mortality in a dose - dependent manner and its LC50 value was calculated to be 994.96 ppm. Dodine did not induce any beetle mortality up to 2000 ppm. In topical application method, the LC50 values for indoxacarb, dimethoate, flubendiamide, fenazaquin and spinosad were determined to be 69.71, 201.90, 415.42, 474.66 and 492.19 ppm, and the order of toxicity was indoxacarb > dimethoate > flubendiamide > fenazaquin > spinosad. Irrespective of insecticides, leaf dip method proved more effective, except indoxacarb.
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    ThesisItemOpen Access
    BIO-ECOLOGY AND MANAGEMENT OF SCIRPOPHAGA FUSCIFLUA HAMPSON
    (CSKHPKV, Palampur, 2018-07-18) Tandon, Vikas; Srivastava, Ajai
    Detailed studies on white stem borer, Scirpophaga fusciflua (Hampson) were undertaken at Rice and Wheat Research Centre of CSK Himachal Pradesh Krishi Vishvavidyalaya at Malan during Kharif season 2015-2017. The studies included white stem borer annual life cycle, its population build-up, assessment of yield losses inflicted and management with suitable insecticides and biopesticides. Three generations of white stem borer were recorded under laboratory conditions. Life history of white stem borer comprised of four well-defined stages viz., egg, larvae, pupa and adult. At the end of the crop season, as the temperature decreased, the full grown larvae diapaused in rice stubbles, adult of which emerged during last week of April to first week of May under laboratory conditions. The female moths on an average laid 58.4 to 65.6 eggs in masses in different generations with pre-oviposition, oviposition and post-oviposition period of 23.8 to 24.1, 24.9 to 26.0 and 6.0 to 6.6 hours, respectively. The larva passed through five instars to complete the larval development and the head capsule width increased with each instar. Population build-up of S. fusciflua was undertaken at three locations viz., Kohala, Jia and Malan. The pest appearance initiated during the month of July and the peak activity of pest was recorded during the month of August and September. The adult population had a positive relationship with minimum and maximum temperature and relative humidity whereas, rainfall influenced adult population negatively. However, the larval population was found to be negatively correlated with minimum temperature, rainfall, relative humidity (morning and evening). The plant infestation was found to have significant negative correlation with temperature (maximum and minimum), relative humidity (morning and evening) and rainfall. Stepwise regression analysis based on the data clubbed for three cropping seasons (2015-2017) revealed that minimum temperature, maximum temperature and rainfall influenced light trap and sweep net catch, significantly. Predators viz., spiders, dragonflies and damselflies, were found associated with white stem borer in paddy ecosystem. Four species of parasitoids viz., Telenomus sp. Tetrastichus sp. Stenobracon sp. and Xanthopimpla punctata were found to be associated with white stem borer. The plant infestation and losses inflicted to paddy due to different release levels of S. fusciflua viz., 2, 4 and 6 larvae per hill released at tillering stage revealed that maximum infestation in terms of dead hearts and white ears was 11.6 per cent at highest release level (6 larvae per hill) and lowest (6.2%) at release level of 2 larvae per hill and per cent avoidable losses varied from 7.5 to 32.3 per cent. Application of various insecticides viz., flubendiamide 48% SC @ 50 ml ha-1, rynaxypyr 20 SC @ 150 ml ha-1, dinotefuran 20 SG @ 200 g ha-1, monocrotophos 36 SL @ 850 ml ha-1 and two biopesticides viz., melia and eupatorium 5% extract @ 2.5 L ha-1 proved promising in checking white stem borer infestation, with flubendiamide being the most effective and more or less comparable with other insecticides. Among biopesticides, eupatorium application provided a significant check. However, maximum returns were obtained from monocrotophos and flubendiamide.
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    ThesisItemOpen Access
    Eco-friendly Management of Rice Weevil, Sitophilus oryzae (L.) on Stored Wheat
    (CSKHPKV, Palampur, 2018-09-29) Mehta, Vasu; Surjeet Kumar
    The studies were conducted in the laboratory of the Department of Entomology, CSKHPKV, Palampur, India during 2017-18 with the objectives to determine relative susceptibility/resistance of seven cultivars of wheat to rice weevil, Sitophilus oryzae (L.) and to evaluate different plant powders as grain protectants against the weevil. The main aim of the study was to find eco-friendly alternatives to the chemical fumigants used against the weevil in stored wheat. On the basis of biological parameters of rice weevil and extent of its damage none of the varieties was found to be free from weevil infestation and damage. However, HPW-249, HPW-349 and HPW-360 were observed to be less susceptible, HPW-155, HS-490 and VL-892 were categorized as moderately susceptible and HPW-236 was highly susceptible. Among seven varieties, HPW-360 had the lowest oviposition (17.33%) and adult emergence (23.33 adults), the longest developmental period (43.67 days), the lowest monthly increase in population (87.0 days), the lowest value of susceptibility index (7.19) and orientation of the weevil (4.33 adults) and least grain damage (26.22%) and weight loss (6.59) while HPW-236 had the highest oviposition (64.0%) and adult emergence (87.33 adults), maximum orientation (27.33 adults) and monthly increase in population (243.44), highest value of susceptibility index (13.55), grain damage (58.67%) and weight loss (18.92%). Different plant powders, evaluated for their effects on the adult mortality and population build-up of S. oryzae and on the extent of damage by the weevil, proved highly effective in comparison to untreated control. The leaf powder of Ageratum conyzoides proved to be the best treatment against the weevil which resulted into maximum mean cumulative mortality (96.67%), the lowest monthly average of population increase (18.33) and the least grain damage (12.61%) and weight loss (1.75%) in six months of storage. The next best treatment was the drupe powder of Melia azedarach followed by Vitex negundo and Ocimum sanctum. These treatments did not cause significant reduction in seed germination. A. conyzoides, M. azedarach and O. sanctum were found effective even after three months of their preparation. The leaf powder of Murraya koenigii resulted into the lowest mean cumulative adult mortality (14.23%), the highest monthly increase in population (132.78), the highest grain damage (47.50%) and weight loss (11.07%) and the lowest germination (21.67%) after five months of treatment. Thus, this treatment proved to be the least effective against the weevil.
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    ThesisItemOpen Access
    EVALUATION OF DIFFERENT ORGANIC PRODUCTS AGAINST INSECT-PESTS OF CABBAGE
    (CSKHPKV, Palampur, 2018-07-24) Thakur, Suman; Sud, Ajay K.
    Present investigations on the “Evaluation of different organic products against insect-pests of cabbage” were undertaken to study the toxicity, bio-efficacy and persitent toxicity of eight organic products namely, cow urine (5%), Dashparni (10%), Eupatorium leaf extract in cow urine (5%), fermented buttermilk (10%), Jeevamrit (10%), Melia drupe extarct in cow urine (5%), neem leaf extract in cow uirne (5%), Panchgavya (10%) and two biopesticide formulations namely, azadirachtin (0.00045%) and Melia 10EC (0.03%) against Brevicoryne brassicae L., Pieris brassicae L. and Plutella xylostella L. Also, their effect on coccinellids activity was observed. Bioefficacy studies conducted during two cropping seasons (2017 and 2018) at Experimental farm of Department of Entomology, CSK HPKV, Palampur revealed that azadirachtin (0.00045%) was most effective against all the insects and was followed by Melia 10EC (0.03%). Among organic products Melia drupe extract in cow urine (5%), followed by Eupatorium leaf extract in cow urine (5%) and neem leaf extract in cow urine (5%) resulted in maximum population reduction of these insects. Whereas cow urine (10%) was least effective in reducing the population. Reduction in B. brassicae population varied between 12.1 to 31.0 per cent, corresponded to cow urine and azadirachtin whereas in P. brassicae, it ranged between 10.1 to 33.5 per cent. Against P. xylostella, the population reduction varied between 11.6 to 35.0 per cent after two consecutive applications of treatments.The lethal toxicity of these organic products/biopesticide formulations against second instar nymphs of B. brassicae nymphs and second instar larvae of P. xylostella revealed that in all the treatments, mortality increased with increase in concentration as well as increase in duration of treatment from 24 to 72 hr. The descending order of B. brassicae nymphs morality in different products/formulations was azadirachtin (86.7%) > Melia 10EC (83.3%) > Melia in cow urine (70.0%) > Eupatorium in cow urine (65.6%) > neem in cow urine (61.9%) > fermented buttermilk (61.5%) > Dashparni (60.0%) > cow urine (57.5%) > Panchgavya (53.3%) > Jeevamrit (46.7%) and for P. xylostella the order was azadirachtin (90.0%) > Melia 10EC (86.7%) > Melia in cow urine (66.7%) > Eupatorium in cow urine (60.4%) > neem in cow urine (56.7%) > Dashparni (53.3%) > Jeevamrit (48.2%) > fermented buttermilk (46.7%) = Panchgavya (46.7%) = cow urine (46.7%).The persistent toxicity studies undertaken revealed that residues of azadirachtin, Melia 10EC, Melia drupe extract in cow urine, Eupatorium leaf extract in cow urine, neem leaf extract in cow urine persisted for 7 days and least was cow urine (5 days). The order of persistence for B. brassicae was azadirachtin (476.0) > Melia 10EC (448.0) > Melia in cow urine (378.0) > Eupatorium in cow urine (350.0) > neem in cow urine (312.7) >Dashparni (251.8) ≥ Panchgavya (224.0) > Jeevamrit (221.2) = fermented buttermilk (199.2) > cow urine (170.8) and for P. xylostella it was: azadirachtin (456.3) > Melia 10EC (423.6) > Melia in cow urine (381.1) > Eupatorium in cow urine (348.4) > neem in cow urine (310.6) > Jeevamrit (273.8) > Dashparni (237.0) ≥ fermented buttermilk (227.4) ≥ Panchgavya (197.9) > cow urine (156.0). Effect of organic products and biopesticide formulations on coccinellid predator complex activity revealed that the organic products reduced their activity to a low level (2.1 to 11.1%) whereas, their activity was adversely affected by azadirachtin (28.8%) and Melia 10EC (23.0%).
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    ThesisItemOpen Access
    POTENTIAL OF ENTOMOPATHOGENS IN INTEGRATED CONTROL OF WHITEGRUBS IN HIMACHAL PRADESH
    (CSKHPKV, Palampur, 2018-10-15) Sanjta, Suman; Mehta, P.K
    The bioassay studies of five entomopathogens viz. Beauveria bassiana, Metarhizium anisopliae, Heterorhabditis indica, Steinernema carpocapsae and Bacillus cereus were conducted against grubs of Holotrichia longipennis and Brahmina coriacea. The entomopathogenic fungi revealed decrease in susceptibility with increase in age. The LC50 values of B. bassiana for I to III instar grubs of H. longipennis ranged from 7.28 x 107 to 1.6 x 108 conidia/ml. In case of B. coriacea, the LC50 values for I to III instars were determined from 5.04x 107 to 1.17x 108 conidia/ml. In H. longipennis and B. coriacea, first instar grubs were 1.12 to 2.43 and 2.85 to 3.84 times more susceptible than second and third instar grubs, respectively. The LC50 values of M. anisopliae for I to III instars of H. longipennis were calculated from 4.36 x 107 to 1.3 x 108 conidia/ml. In case of B. coriacea, M. anisopliae produced 50 per cent kill at a concentration range of 4.9 x 109 to 3.2 x 108 conidia/ml in I to III instar grubs. In H. longipennis, first instar grubs were 2.06 and 2.98 times more susceptible than second and third instar. In case of B. coriacea, the increase in LC50 for second and third instar in comparison to first instar was 2.24 to 3.67 times. The grubs of H. longipennis were found comparatively more susceptible to both entomopathogenic fungi and B. bassiana was found to be less virulent as compared to M. anisopliae. Two entomopathogenic nematodes viz. H. indica and S. carpocapsae were evaluated by soil inoculation method. Against H. longipennis, the LC50 values of H. indica for I to III instars ranged between 324.15 to 796.18 IJs/ml. In case of B. coriacea, the LC50 values of H. indica against I to III instars were calculated from 444.84 to 845.18 IJs/ml. S. carpocapasae produced 50 per cent kill in respective instars of H. longipennis at concentrations ranging from 408.63 to 910.67 IJs/ml. In B.coriacea, a dose of 474.26 to 1620.34 IJs/ml of S. carpocapsae is required to produce 50% kill. There was 1.70 and 2.4 times increase in LC50 values of H. indica in first instar of H. longipennis as compared to second and third instars, respectively. In B. coriacea, the corresponding increase was 1.4 and 1.89 times. S. carpocapsae proved less effective as compared to H. indica, and H. longipennis was found to be more susceptible to entomopathogenic nematodes as compared to B. coriacea. B. cereus was found to be least effective among tested entomopathogens. In I to III instars of H. longipennis and B. coriacea, the LC50 values of B.cereus varied from 5.62 x 108 to 1.7 x 109 spores/ml. Among tested insecticides, clothianidin was found highly effective with LC50 values ranging from 129.86 to 457.11 ppm. In case of imidacloprid and chlorpyriphos, the LC50 values ranged from 238.38 to 811.81 ppm, and 334.44 to 911.44 ppm in different instars of H. longipennis and B. coriacea. To interaction studies of different entomopathogens with imidacloprid, chlorpyriphos and clothianidin have shown to produce strongest interaction with the tested insecticides in both the species of whitegrubs. Imidacloprid revealed maximum synergism with H. indica and S. carpocapsae. There was consistent antagonistic interaction among B. cereus and imidacloprid or chlorpyriphos. Under field conditions, combined application of H. indica+imidacloprid in potato gave 34.53 to 40.67 % reduction in tuber damage over control.
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    ThesisItemOpen Access
    Bioefficacy of biopesticides and novel insecticides to Leucinodes orbonalis Guenee and their safety to natural enemies
    (CSKHPKV, Palampur, 2018-07) Sharma, Sugandha; Chandel, Y.S.
    Studies on the bioefficacy of biopesticides and novel insecticides to L. orbonalis and their safety to natural enemies was undertaken at CSK Himachal Pradesh Krishi Vishvavidyalaya, Palampur. The lethal concentrations computed against first instar larvae of L. orbonalis revealed cyantraniliprole as most effective with LC50 and LC90 values of 0.18 and 0.95 ppm followed by chlorantraniliprole (1.24 & 8.64 ppm), thiacloprid (14.43 & 95.09 ppm), indoxacarb (19.99 & 106.71), lambda-cyhalothrin (38.62 & 207.78 ppm), azadirachtin (57.06 & 316.34 ppm), melia (73.82 & 378.09 ppm) and eupatorium (97.84 & 477.85 ppm). Under bioefficacy studies, chlorantraniliprole resulted in minimum shoot infestation followed by cyantraniliprole, lambda-cyhalothrin, thiacloprid, indoxacarb, azadirachtin, melia and eupatorium during 2015, whereas, during 2016 the shoot infestation was minimum in cyantraniliprole followed by chlorantraniliprole, thiacloprid, lambda-cyhalothrin, indoxacarb, azadirachtin, melia and eupatorium. Fruit infestation was found minimum in chlorantraniliprole followed by cyantraniliprole, thiacloprid, lambda-cyhalothrin, indoxacarb, azadirachtin, melia and eupatorium during both the years. On the basis of index of mean persistent toxicity of 2015 & 2016, the order of effectiveness of biopesticides and novel insecticides was: chlorantraniliprole (608.34) > cyantraniliprole (580.56) > thiacloprid (519.44) > lambda cyhalothrin (409.72) > indoxacarb (297.50) > azadirachtin (256.67) > melia (213.44) > eupatorium (136.11). Studies on dissipation pattern of insecticides revealed the average recovery of 87.75 and 91.10 per cent of indoxacarb and thiacloprid, respectively through RP-HPLC. The LOD and LOQ were 0.009 and 0.03 mg/kg for indoxacarb, 0.015 and 0.05 mg/kg for thiacloprid, respectively. The initial deposit of indoxacarb and thiacloprid were 0.620±0.025 and 1.078±0.011 mg/kg during 2016 with 0.4 and 1.6 day(s) waiting period, respectively and 0.622±0.015 mg/kg and 1.133±0.044 mg/kg during 2017 with 0.4 and 1.7 day(s) waiting period, respectively. Laboratory and field studies on relative safety of all the treatments to T. chilonis showed azadirachtin, chlorantraniliprole, cyantraniliprole, melia & eupatorium safer to the parasitoid and lambda-cyhalothrin as highly toxic.
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    ThesisItemOpen Access
    Seasonal abundance of insect-pests of brinjal and evaluation of organic products for their management
    (CSKHPKV, Palampur, 2018-08) Sood, Shagun; Sharma, Prem Chand
    The present investigations entitled "Seasonal abundance of insect-pests of brinjal and evaluation of organic products for their management" were conducted at Experimental Farm, Department of Entomology, CSKHPKV, Palampur during Kharif 2017 to study the seasonal incidence and bio-efficacy of seven organic products namely, Agniastra (5%), Brahmastra (5%), Cow urine (10%), Darekastra (10%), Jeevamrit (10%), Panchagavya (10%), Tamralassi (5%) and one insecticide emamectin benzoate (0.002%) against Leucinodes orbonalis. Seasonal incidence of Amrasca biguttula biguttula was apparent from 30th SW and the peak population was observed during 37th SW (8.11 jassids/ 3 leaves). The trap catch data of L. orbonalis adult moths showed that incidence started from 29th SW and maximum number of moths were trapped in 37th SW (19 moths/ week). Bioefficacy studies revealed that among the organic products, Agniastra (5%), Brahmastra (5%) and Cow urine (10%) were effective against L. orbonalis. However, emamectin benzoate was superior to all the organic products. In Set 1(prophylactic sprays), maximum mean shoot infestation was observed 7 days after ninth spray (15.63%) while in Set 2 (sprays applied after the appearance of pest), it was observed 7 days after fifth spray (22.92%). In Set 1, the descending order of efficacy of treatments in terms of shoot infestation by L. orbonalis was emamectin benzoate > Agniastra > Brahmastra > cow urine > Jeevamrit > Darekastra > Panchagavya > Tamralassi. In Set 2, the descending order of efficacy of treatments was emamectin benzoate > Agniastra > cow urine > Brahmastra > Panchagavya > Tamralassi > Darekastra >Jeevamrit. In Set 1, the descending order of efficacy of treatments against fruit infestation (number and weight basis) by L. orbonalis was emamectin benzoate > Agniastra > Brahmastra > cow urine > Jeevamrit > Darekastra > Tamralassi > Panchagavya. In Set 2, the descending order of efficacy of treatments against fruit infestation (number basis) was emamectin benzoate > Agniastra > Brahmastra > cow urine > Darekastra > Panchagavya > Tamralassi > Jeevamrit. In Set 2, the descending order of efficacy of treatments against fruit infestation (weight basis) by L. orbonalis was emamectin benzoate > Agniastra > Brahmastra > cow urine > Darekastra > Tamralassi > Panchagavya > Jeevamrit. In both the sets, maximum mean total number and weight of fruits as well as maximum mean number and weight of marketable fruits were obtained with emamectin benzoate
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    ThesisItemOpen Access
    INSECT PEST COMPLEX OF ONION IN HIMACHAL PRADESH
    (CSKHPKV, Palampur, 2018-07-23) Kaundal, Priyanka; Sood, Ajay K.
    Studies on „Insect pest complex of onion in Himachal Pradesh‟ were made in ten localities representing two agro-ecological zones of Himachal Pradesh and at CSK Himachal Pradesh Krishi Vishvavidyalaya, Palampur. Thirteen species of insects belonging to six orders and nine families, including ten pestiferous and three beneficial insects were recorded from Zone I and II of Himachal Pradesh. The pestiferous insects were Altica sp., Chromatoyia horticola (Goureau), Euconocephalus sp., Gryllus sp., Helicoverpa armigera Hubner, Melolontha furicicauda Ancey, Nezara viridula Linnaeaus, Spodoptera litura Fabricius, Thrips tabaci Lindeman and Trichoplusia orichalacea Fabricius. The beneficial insects namely, Coccinella septempunctata Linneaus, Coccinella transversalis Fabricius and Hippodamia variegata Goeze were associated. In Zone I and II, nine and ten insect species were recorded at different crop growth stages. T. tabaci and C. septempunctata were prevalent in all the ten localities in bulb initiation and bulb development stage. Abundance of T. tabaci was maximum at bulb development stage. In Zone I, diversity and evenness was observed to be maximum at Berthin and Una, respectively. In Zone II, it was observed to be at Palampur. Diversity was maximum during bulb initiation stage and was followed by bulb development. In Zone I, only T. tabaci was found to be eudominant and other eight were subrecedent. Whereas in Zone II, one eudominant (T. tabaci), one recedent (Altica sp.) and eight subrecedent species were recorded. At Palampur, in rabi onion, thrips activity initiated in mid of February with peak population levels of 4.93 and 4.65 thrips/plant occurring in 2nd fortnight of April during 2017 and 2018, respectively. The peak infestation levels of 69.7 and 69.3 per cent corresponded to the peak population. Thrips population was found to be influenced by maximum and minimum temperature positively and significantly. In late kharif onion, thrips activity initiated during the last week of October with peak population of 4.84 thrips/plant occured in mid December and peak of plant infestation (86%) occurring in second fortnight of December. In all the cropping seasons, thrips population was distributed aggregately. For estimation of thrips population the mean number of samples were 16767, 834 and 241 (P=0.1) and 4192, 209 and 60 (P=0.2) for vegetative, bulb initiation and bulb development stage, respectively in rabi onion. For late kharif onion, sample size of 297 and 140 (P=0.1) and 74 and 35 (P=0.2) was required for scape formation and bulb development to maturity stages, respectively. For precise estimation of thrips population in mid-hill regions of the state, 13:00 hours was found to be the appropriate time of sampling thrips in onion.
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    ThesisItemOpen Access
    POPULATION BUILD UP OF RICE CASEWORM AND WHORL MAGGOT UNDER MID HILL CONDITIONS OF HIMACHAL PRADESH
    (CSKHPKV, Palampur, 2018-06-02) Neeru; Srivastava, Ajai
    The present investigation entitled “Population build up of rice caseworm and whorl maggot under mid hill conditions of Himachal Pradesh” were conducted at CSK Himachal Pradesh Krishi Vishvavidyalaya, Rice and Wheat Research Centre, Malan during kharif 2017. Population build up of rice caseworm and whorl maggot through larval population, light trap and sweep net were recorded. Adult activity of both rice caseworm and whorl maggot was observed first in 3rd week of July (29 SW) as recorded through light trap and sweep net. Rice caseworm remained active till 38 SW (4th week of September, 2017) and was at its peak during 32 SW (2nd week of August). Similarly whorl maggot remained active till 38 SW (4th week of September, 2017) and attained its peak during 34 SW (4th week of August, 2017). Correlation studies of light trap collection with abiotic factors indicated that the maximum temperature favours the development of rice caseworm whereas, minimum temperature favours the development of whorl maggot. About eleven natural enemies were found in the paddy fields out of which nine were generalized predators and two i.e. Trichogramma chilonis and Tetrastichus spp. were the specific parasitoid of whorl maggot. Among different treatments, dinotefuran (200 g ha-1) and monocrotophos (850 ml ha-1) were found most effective for the control of rice caseworm and whorl maggot, respectively.