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ThesisItem Open Access Developmental biology of yellow stem borer, Scirpophaga incertulas Walker and diversity of soil arthropods in rice under elevated CO2 condition(Department of Entomology, OUAT, Bhubaneswar, 2022-08-04) Mohapatra, Munmun; Mohapatra, S.D.; Padhi, J.; TripathY, S.K.; Mishra, M.K.The studies on “Developmental biology of Yellow stem borer, Scirpophaga incertulas Walker and diversity of soil arthropods in rice under elevated CO2 condition” was conducted in Open Top Chamber (OTC) at ICAR-National Rice Research Institute (NRRI), Cuttack, Odisha during the rabi 2017-18 and 2018-19. Elevated CO2 exhibited negative effect on the biology of YSB with delayed developmental period. The incubation period and adult longevity were decreased but the larval and pupal period were significantly increased under elevated CO2 compared to ambient. Thus elevated CO2 prolonged the total life-cycle by 5-6 days (Female: 48.5 and 45.53 days; Male: 48.4 and 45.4 days under 700 & 550 ppm CO2 respectively) from ambient (F: 42.8 days; M: 42.65 days). The adult emergence, sex-ratios and fecundity were significantly reduced under elevated CO2 than ambient. The reduced fecundity (139.8 and 143.7) under elevated CO2 (700 and 550ppm respectively) over ambient (154.3) may decrease the number of generations in future. The length, width, head width and body weight of larval instars were increased whereas the weight of pupae was decreased under elevated CO2 than ambient condition. The biochemical contents such as chlorophyll, carbohydrate content of healthy rice plant (leaf and stem) were increased but protein and phenol content were decreased under elevated CO2 compared to ambient CO2. After YSB infestation, the above biochemical contents in infested plant were significantly decreased under elevated CO2 than ambient condition. Elevated CO2 had significant positive effect on the growth and yield of healthy rice plant. The plant growth parameters such as number of tillers per hill, number of reproductive tillers per hill, plant height, number of leaves per hill, stem weight and yield attributing parameters such as number of grains per panicle, number of filled grains per panicle were increased resulting increase in yield of rice under elevated CO2. Elevated CO2 exhibited higher YSB infestation in the form of “Dead heart” and “White ear head” than ambient. Despite the positive effect of elevated CO2 higher YSB infestation reduced the growth of rice plant resulting in higher yield losses under elevated CO2 compared to ambient CO2. Elevated CO2 significantly affected abundance of soil arthropod population in the rice field due to changes in soil edaphic factors such as temperature and moisture. The density and relative abundance of soil arthropod population were decreased with increase in temperature and decrease in moisture content of soil under elevated CO2. Collembola was the most dominant group followed by Acari and other groups under both ambient and elevated condition. The soil arthropod population were more diverse under elevated CO2 compared to ambient condition.ThesisItem Open Access Genetic diversity, insecticide resistance development and semiochemicals synergism of fall armyworm, Spodoptera frugiperda Smith (Lepidoptera: Noctuidae)(Department of Entomology, OUAT, Bhubaneswar, 2022-04-30) Krishnarao, Gandham; Sarangi, Pravat Kumar; Jayanthi, P. D. Kamala; Samal , T.; Samal, K. C.The Fall Armyworm (FAW), Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), is an invasive pest, and has become a threat to global food security vis-à-vis Indian agriculture. Because of its polyphagous nature, quick dispersal behaviour across wide geographical areas, and year-round occurring, FAW is a far more damaging pest than any other invasive pest. Understanding the distribution, population diversity, insecticide resistance development (if any), and adult olfaction of S. frugiperda is crucial for developing a comprehensive management approach. The occurrence and intensity of S. frugiperda in commercially grown maize fields of different geographical regions in Odisha, Andhra Pradesh and Telangana during 2019 to 2021 revealed that the infestation of FAW ranged from 14.33 ± 2.33 to 45.66 ± 1.45 per cent. Simultaneously, highest per cent incidence was observed in Telangana (35.72 ± 2.66) followed by in Andhra Pradesh (26.51± 1.62 per cent) and Odisha (23.16 ± 1.97). The current study highlights that the FAW has spread all over the Odisha, Andhra Pradesh and Telangana causing potential damage to the maize crop in these regions. Documenting the nature of population genetic variation, its magnitude and distribution is essential in understanding FAW behaviour, its response to selection pressure and population structure. Accordingly, molecular characterization of different populations belonging to various maize growing regions in India was carried out using Mitochondrial Cytochrome Oxidase-I (mt COI). Phylogenetic analysis of the mt COI, indicated no significant molecular diversity across the populations of S. frugiperda from different geographical locations of India. Across the globe, FAW has acquired insecticide resistance, thus it's crucial to test its sensitivity to different functional groups of insecticides to chalk out management strategies. In the current study, low to moderate resistance levels were found against nine distinct insecticides from various mode-of-action groups that are mostly used in India. LambdaCyhalothrin had the highest resistance ratio in Odisha, whereas Chlorantraniliprole had the highest resistance ratio in Andhra Pradesh. The present findings establish a baseline for future FAW resistance monitoring initiatives and emphasize the need of insecticide resistance management strategies in India for managing the alien pest. Olfaction plays a fundamental role in modulating the insect behaviours’ such as mating, foraging and oviposition. In the present investigation, electrophysiological studies, choice assays involving healthy, HIPVs (Herbivore induced plant volatiles), EAD (Electro antennographic detection) active compounds and synthetic blends were carried out to find potent host cues that influence gravid S. frugiperda. Findings revealed that gravid female moths strongly respond to maize volatiles. Moreover, gravid females preferred volatiles released by healthy plant over HIPVs. Definite concentration of specific cues released by healthy maize plant like D-Limonene, n-Undecane, Ethyl benzoate, Methyl Salicylate, n-Decanal and βCaryophyllene might play decisive role in selection of healthy maize plant. This preference for healthy plants may reflect an adaptive strategy of moths to avoid competitors and natural enemies for their offspring. Further, laboratory experiments were also conducted to find a suitable pheromone blend for trapping FAW. Results revealed that pheromone blends with (Z)- 9-tetradecenyl acetate: (Z)-7-dodecenyl acetate: (E)-7-dodecenyl acetate and (Z)-9-tetradecenyl acetate: (Z)-7-dodecenyl acetate: (Z)-11-hexadecenyl acetate in the ratio of 95: 5: 10 was found to be more effective in attracting the male S. frugiperda. Unfortunately, synergism studies of kairomone and pheromone blend exhibited non significant response to both male and female S. frugiperda. In conclusion, the present study revealed host plant volatile induced antagonism in S. frugiperda male and female moths, which can be a potential clue for semiochemical based behavioral manipulation in the field.ThesisItem Open Access Development of insecticide resistance in Black legume aphid, Aphis craccivora Koch. to thiamethoxam(Department of Entomology, OUAT, Bhubaneswar, 2020) Routray, Snehasish; Mishra, H.P.; Rath, L.K.; Mishra, M.K.; Mohanty, I.C.A laboratory study was undertaken to assess the magnitude of resistance development to thiamethoxam in black legume aphid, Aphis craccivora Koch. reared in cowpea crop at the Department of Entomology, College of Agriculture, Odisha University of Agriculture and Technology, Bhubaneswar during 2015-2017. Adult apterous aphids were collected from untreated cowpea crop from Central Research Station, OUAT, Bhubaneswar and reared in the insectary of Department of Entomology for several generations in cowpea plants (cv. Gomati) without thiamethoxam spray to obtain a susceptible parental line. The baseline toxicity of thiamethoxam to A. craccivora was determined to be 2.62 ppm using leaf-dip bioassay method. Further selection progressed with a selection pressure of LC60 of thiamethoxam every alternate generation. The degree of resistance to thiamethoxam was estimated to be 1.32 (F2), 2.71 (F4), 8.96 (F6), 11.95 (F8), 17.96 (F10), 18.61 (F12), 28.97 (F14), 69.36 (F16), 75.02 (F18), 76.17 (F20), 79.08 (F22) and 86.19 (F24)- folds when compared with the parental line (F0). The projected rate of resistance development to thiamethoxam calculated from realized heritability (h2 ) studies revealed 13 to 5 generations would be required for a 10-fold increase in the resistance as the selection intensities increase from 50 to 95 per cent, respectively. While studying the reversion pattern of resistance, taking off the selection pressure of thiamethoxam from F24 generation resistant strain of aphids, it was found that only 18 generations are required by the resistant strain to revert to susceptibility indicating that thiamethoxam resistance in A. craccivora is unstable and acquired one. The persistent toxicity studies revealed that different doses of thiamethoxam persisted in cowpea plants for 11 to 23 days. The relative efficacy of insecticides evaluated in terms of persistency was thiamethoxam @ 35 g a.i./ha > imidacloprid @ 25 ml a.i./ha > thiamethoxam @ 30 g a.i./ha > thiamethoxam @ 25 g a.i./ha > diamethoate @ 300 ml a.i./ha > thiamethoxam @ 20 g a.i./ha when mortalities of aphids were studied 24 hours after release. Elevated levels of the detoxifying enzymes, Carboxylesterase (×42.02), Glutathion-s-transferase (×3.01) and Mixed function oxidases (×7.05) in the resistant strain of A. craccivora compared to susceptible strain indicated the role of detoxifying enzymes in resistance development in the black legume aphid, more particularly the Carboxylesterases whose activity was maximum in ‘R-strain’. The fitness of the thiamethoxam strain of aphids decreased in terms of reduced fecundity which was 16.00±5.34 in F24 compared to 54.71±7.63 in F0. The pre oviposition period (0.57±0.18 days in F0 to 1.60±0.34 days in F24), oviposition period (7.78±1.40 days in F0 to 8.89±1.27 days in F24) and post-oviposition period (1.14±0.24 days in F0 to 2.00±0.37 days in F24) was found increased in R-strain of aphids compared to its susceptible counterparts indicating reduced fitness of resistant aphids.ThesisItem Open Access Role of silicon in enhancing resistance of rice plants to brown planthopper, Nilaparvata lugens (Stal) under acidic soil of Odisha(Department of Entomology, OUAT, Bhubaneswar, 2021) Roy, Subhalaxmi; Panda, S.K.; Rath, L.K.; Pattnaik, S.K.; Rout, G.R.; Swain, S.K.An investigation entitled “Role of silicon in enhancing resistance of rice plants to brown plant hopper, Nilaparvata lugens (Stal) under acidic soil of Odisha” comprising field, pot culture and laboratory experiments was undertaken in Orissa University of Agriculture and Technology, Bhubaneswar during Kharif and rabi seasons of 2016 and 2017 to ascertain the role of silicon in inducing resistance against brown plant hopper (BPH) and understand the underlying mechanisms. Two organic products such as diatomaceous earth (DAE) at 0.15, 0.30 and 0.45 t/ha and rice hull ash (RHA) at 2, 3, 4 t/ha along with one in organic source, calcium silicate (CaSiO3) at 2, 3, 4t/ha were soil applied as basal for studying the source specific Si mediated plant response to BPH. Silicon amendment through different sources and doses significantly reduced BPH population under field situation during the entire crop growth stages. The dose-response was positive in all the test products exhibiting better performance in restricting pest damage at its higher dose. At the peak activity of hoppers the supremacy of medium and high doses of DAE was observed in arresting the pest population to 11.6-15.7 and 15.6-20.5 hoppers/hill during kharif and rabi seasons respectively compared to 65.6 and 57.3 hoppers/hill in control. The residual effect of RHA at low dose was good enough to restrict hopper build up till the flag end of the crop signifying the importance of this cheap technology. On the other hand Si amendments have no adverse impact on predatory spiders and mirid populations that varied in a pest density-dependent manner. Si supplements resulted in increase in plant height, tiller thickness and leaf length by a maximum of 17.9, 24.0 and 18.9 percent respectively in plots received high dose of RHA over control. The chlorophyll content was also increased in different Si amended treatments highest (1.65 mg/gm) being in high dose of CaSiO3 compared to control (1.33 mg/gm ). Invariably the medium doses of all the three sources yielded higher and remained on par with those of high doses. RHA at 3 t/ha consistently yielded more than 30 % extra over control exhibiting its importance as a cheap and abundantly available local source of Si. Studies on insect growth parameters revealed a significant reduction in nymphal duration (13.77-14.13 days) and adult emergence (3.33-66.67 %) at higher doses of amendments compared to 16 days and 90-93% in control. A marginal reduction in growth index (4.2-5.35) due to addition of silicon over control (5.55-5.79) was observed in a dose dependent manner. Scanning electron microscopy revealed higher number of silica cells and silica body per unit leaf length in Si amended plants, which varied in a dose dependent manner as against a sparsely distributed silica bodies in control sample. Laboratory estimates showed increased proline accumulation in Si amended infested rice plants (9.01-11.88 μ moles/g) compared to its healthy counterparts (4.25 -10.37 μ moles/g) but remained lower than that of control (11.78-12.21 μ moles/g). On the other hand there was a significant increase in phenol contents due to greater accumulation of Si in rice. BPH feeding altered the phenol content of plants at both vegetative (7.23-12.21 mg/g) and reproductive stages (9.10-12.68 mg/g), which were significantly higher over the healthy ones (2.48-6.11 and 4.54-8.50 mg/g). Carbohydrate content increased in Si amended plants with a strong evidence of greater carbohydrate accumulation in response to BPH feeding. Lower protein content in plants receiving Si and prominence of 20 KDa fragment amongst 10-14 numbers of 0.5-96 KDa protein bands was attributed towards plant defense against this hopper. Silicon mediated plant response through alterations in insect defence enzyme activity showed a significant reduction in catalase (CAT) activities to the tune of 85% in Si treated plants in reproductive phase and 65% in vegetative stage compared to control (without Si amendment) indicating the role of Si in down regulating the CAT activity in rice plants. Similarly, reduced POD activities in plants with higher doses of DAE and CaSiO3 supposed to have contributed to plant resistance during both vegetative and reproductive stages. Si amendment also down regulated the SOD production in rice plants both at vegetative and reproductive stages, which was further reduced when coupled with BPH infestation. Thus, results of this study clearly demonstrated the role of organic and inorganic sources of Si through soil basal application in effectively containing the BPH severity in rice field, which may either be due to direct effects of intensified silicification of leaf tissues or indirect effect of activity priming of both antioxidative enzymes and secondary metabolic compounds. Considering the overall impact of Silicon amendments on N.lugens, its availability in the locality and price, RHA at 3 t/ha considered to be the best treatment, and should be recommended for integration as an eco-friendly approach into the BPH management programme in hopper endemic pockets.ThesisItem Open Access Bioecology and feeding potential of some important coccinellid predators of Odisha(Department of Entomology, OUAT, Bhubaneswar, 2019) Mishra, Ipsita; Sontakke, B.K.; Rath, L. K.; Mohapatra, S. S.; Sahoo, N.K.Laboratory and field experiment were conducted during 2013-14 to study the bioecology and feeding potential of some important coccinelid predators of Odisha. About 17species of predatory coccinellids were identified from different crops.The most important being C.septempunctata , C.transversalis and C.sexmaculata in aphid infested plants and B sutularis and S coccivora being abundant in mealy bug infested plants. The biological parameters indicated that C.septempunctata was the largest and C.sexmaculata was the smallest among the aphidophagous coccinellids. Similarly, C montrouzieri was the largest and S coccivora was the smallest among the coccidophagous ones. The studies on the feeding potential of the predatory coccinellids revealed that C.septempunctata consumed maximum aphids followed by C.transversalis and C.sexmaculata whereas among the coccidophagous predatory coccinellids, C montrouzieri consumed maximum mealy bugs followed by B sutularis and S coccivora. The grubs of all the predatory coccinellids were found to be most susceptible to the rising temperatures. Therefore, it was observed that mortality of the grubs was highest in the month of May and lowest in the month of January. Pre pupae and pupae were least affected by the fluctuation of temperature. Significant negative correlation was observed for all the species in respect of fecundity and egg viability. The correlation was also highly significant and negative in respect of all the larval stages. Total developmental period of all the beetles had significant negative correlation with maximum, minimum and mean temperatures whereas, there was insignificant negative correlation with relative humidity. C. septempunctata and C. montrouzieri showed highest survivor fraction and lowest apparent mortality, mortality survival ratio indispensable mortality and k-values as compared to the other species of aphidophagus and coccidophagus coccinellids respectively. Minimum total generation mortality (k) was recorded (k=0.1427) for C.septempunctata and C montrouzieri (k=0.1676) among the aphidophagus and coccidophagus coccinellids indicating that they are the best survivors among the lot. Among the predatory coccinellids, Coccinella septempunctata and Cryptolaemus montrouzieri were found to be the most efficient in regards to their feeding potential on aphids and mealy bugs respectively. Therefore, these two were evaluated under field trials during 2013 and 2014 Kharif in Brinjal affected by mealy bugs and Cowpea affected by aphid. It was cobserved that, the release of 10 and 20 numbers of beetle grubs could successfully control the mealy bug and aphid and the yield was also at par with that of insecticidal application. Among the insecticides evaluated against the coccinellids for their toxicity, it was observed that Methyl demeton was the most toxic one followed by Dimethoate. The newer molecules were found to be comparatively less toxic to the predatory beetles. Therefore, it can be concluded that, the sucking pests of crops can be managed by the use of coccinellid predators in combination with the judicious use of safer molecules of insecticides.ThesisItem Open Access Combined action of silicon and bio-fertilizers in inducing resistance against major insect pests of rice(Department of Entomology, OUAT, Bhubaneswar, 2021) Dash, Subhashree; Rath, L. K.; Mukherjee, S. K.; Rout, G. R.; Mohanty, S.The field and laboratory study on “Combined action of silicon and bio fertilizers in inducing resistance against major insect pest of rice” were undertaken during kharif, 2016, kharif, 2017 and rabi, 2016-17 in the Department of Entomology, College of Agriculture, OUAT, Bhubaneswar to evaluate the importance of exogenous application of silicon and bio fertilizers alone and/or in combination for controlling major insects pests of rice like yellow stem borer, Scirpophaga incertulas, leaf folder , Cnaphalocrocis medinalis and white backed plant hopper, Sogatella furcifera through induced resistance. One organic compound i.e. Rice hull ash (RHA) @ 4 t/ ha and one inorganic source i.e. CaSiO3 @ 2t/ ha with two bio fertilizers Pseudomonas fluorescence (PF) @ 10 kg/ha and Potassium solubilising bacteria (KSB) @ 10 l/ha were evaluated for their efficacy in controlling the above three insects of rice and compared with control treatment. A total of twelve treatments were evaluated both under field and laboratory situation. The standard method for field efficacy study and laboratory analysis of plant samples were followed. The study revealed that CaSiO3 +PF+KSB (T5) reduced the yellow stem borer, leaf folder and white backed plant hopper infestation substantially followed by RHA +PF+KSB (T8) and CaSiO3 + KSB (T4), respectively. The treatments, T5 (CaSiO3 + PF + KSB), T8 (RHA + PF + KSB) and T4 (CaSiO3 +KSB) caused 59.68, 56.03 and 58.10 per cent decline in stem borer incidence during kharif, seasons (pooled) while the same treatments in rabi, 2016-17 caused 50.13, 50.92 and 45.41 per cent reduction in stem borer incidence. Similarly, these three treatments (T5, T8 and T4) caused 59.07, 60.40 and 53.87 per cent reduction in leaf folder infestation during kharif, seasons whereas, the per cent reduction in leaf folder infestation during rabi, 2016-17 were, 60.92, 57.04 and 53.17 per cent, respectively. So far WBPH population was concerned there was decline in infestation to the tune of 71.53, 71.59 and 68.95 per cent in T5, T8 and T4, respectively during kharif seasons whereas, during rabi, 2016-17 these three treatments caused 72.84, 68.44 and 58.27 per cent reduction, respectively. These three treatments possessed higher silicon content both at vegetative and reproductive stages of rice which favoured mirid bug populations. Higher silicon content in these three treatments caused higher grain yield with higher benefit cost ratio. High silica content caused lowering in N, Fe and Mn content whereas, favoured enhanced level of P, K, S, Ca and Mg content. Silicon at higher level in the above mentioned treatments had lower soluble protein and proline content whereas, induced more phenol, SOD and POD activity. Induction of more phenol and enhanced SOD and POD activities are considered to be antibiosis component against herbivores. The results of pot culture study with only YSB infestation on rice also indicated that the treatment viz., CaSiO3 + PF + KSB, RHA + PF + KSB and CaSiO3 +KSB reduced DH percentage. These three treatments also caused a rise in silicon content which ultimately exercised induced defence mechanism in rice through improvement of phenol, SOD and POD content that are considered as induced defence parameters in rice.ThesisItem Open Access Seasonal incidence and bio-intensive management of fall armyworm, spodoptera frugiperda (J.E.Smith) (Lepidoptera: Noctuidae) on maize(Department of Entomology, OUAT, Bhubaneswar, 2021) Pasayat, Manasi Madhubhasini; Samal, Tribikram; Rath, L. K.; Mishra, M.K.Field experiments on “Seasonal incidence and bio-intensive management of fall armyworm, Spodoptera frugiperda (J.E. Smith), (Lepidoptera: Noctuidae) on maize” were conducted during rabi 2020-21 at Research Farm of Department of Entomology, Odisha University of Agriculture and Technology, Bhubaneswar. The incidence of S. frugiperda commenced from the 50thstd week (10 Dec-16Dec) and continued up to 9thstd week(Feb26- March4) of the next calendar year. The mean larval population of S. frugiperda ranged 0.03 to 3.90 /plant with the peak during 5thstd week (Jan29-Feb04) synchronizing with vegetative growth stage. The pest damaged 7.20 to 30.32 per cent plant damage during growth stages of the crop. Minimum temperature, and rainfall had a negative influence on the population fluctuation of S. frugiperda during Rabi 2020-21 where as maximum temperature adversely affected S. frugiperda population. Maximum activity of ladybird beetle (0.69/plant) was noticed during 5 th SW (Jan29-Feb04) coinciding with the peak occurrence of S. frugiperda(3.90 larvae/plant).Among the various bio-intensive and insecticidal modules tested against S. frugiperda, foliar spray of Emamectin benzoate 5% SG @ 0.4g/l at 30,45 and 60 DAS(days after sowing) afforded excellent control of S. frugiperda with the highest cob yield of 14.70thousand cobs/ha and benefit cost ratio (8.09: 1) but was injurious to natural enemies(64.20% reduction of population of spider). Among all the bio-intensive modules, releases of (Trichogramma pretiosum @ 1card/acre and Metarhizium anisopliae NBAIR Ma-35 @0.5%) at 30, 45 and 60 DAS (days after sowing) was found moderately effective by decreasing the incidence of S. frugiperda (65.75%larval population reduction), producing a higher cob yield (13.00thousand cobs/ha) with higher benefit cost ratio (4.06:1). Hence, this combination of (T.pretiosum @ 1card/acre and Metarhizium anisopliae NBAIR Ma-35 @0.5%) may be recommended for control of fall army worm in maize.ThesisItem Open Access Insecticide management of foliage feeding insects in potato(Department of Entomology, OUAT, Bhubaneswar, 2021) P. G., Sathvik; Sasmal, Arundhati; Rath, L. K.; Mishra, AshokA field experiment was conducted at experimental plots of AICRP on potato, Bhubaneswar, in collaboration with Regional Research and Technology Transfer Station (RRTTS), Coastal zone, OUAT, Bhubaneswar, Odisha in randomized block design with seven treatments replicated thrice during Rabi seasons of 2019-20 and 2020-21 to evaluate the efficacy of insecticides viz., Azadirachtin 0.03% w/w@1500ml/ha, Cypermethrin 25% EC @200ml/ha, Fipronil 5% SC@1000ml/ha, Spinosad 45% SC @187.5ml/ha, Cartap hydrochloride 50% SP @1000g/ha, Chlorpyriphos 20% EC @2000ml/ha sprayed twice at 30 days after planting and 45 days after planting against foliage feeding insect pests of potato (Solanum tuberosum) cv. “Kufri Jyoti” compared with untreated control. On introspection in to the results it was revealed that the treatment Cartap hydrochloride 50% SP @1000g/ha was most effective in suppressing foliage feeding insect pests of potato i.e., epilachna beetle (0.7 beetles/ plant with 85.41% reduction over control (ROC), flea beetle (0.8 beetles/plant with 82.98% ROC), Tobacco caterpillar (0.3 caterpillars/ plant with 90.91% ROC), cut worms (0.2 caterpillars/ plant with 88.89% ROC), semilooper (0.2 caterpillars/ plant with 93.10% ROC), in Helicoverpa it was the second-best treatment (0.8 caterpillars/ plant with 79.49%ROC), and was found relatively safer to predatory coccinellids (1.4 coccinellids/ plant) while Azadirachtin 0.03% w/w@1500ml/ha was the safest (2.6 coccinellids/ plant). The plots treated with Cartap hydrochloride 50% SP @1000g/ha also recorded the highest pooled mean yield (14.10 t/ha) and gave the highest monetary benefit of Rs. 85,480 /ha.ThesisItem Open Access Effect of biopesticides on Chrysoperla zastrowi sillemi (Esben-Peterson) (Neuroptera- Chrysopidae)(Department of Entomology, OUAT, Bhubaneswar, 2021) Devi, Moirangthem Monalisa; Mukherjee, S. K.; Rath, Ladu Kishore; Biswal, G.The laboratory experiment entitled “Effect of biopesticides on Chrysoperla zastrowi sillemi (Esben-Peterson) (Neuroptera:Chrysopidae)” was carried out at Biocontrol laboratory, Department of Entomology, College of Agriculture, OUAT, Bhubaneswar during 2020-21. During this course of investigation, the effect of 5 biopesticides viz. Bacillus thuringiensis, Lecanicillium lecani, Beauveria bassiana, Metarhizium anisopliae, Azadirachtin and chemical check, fipronil were evaluated on Chrysoperla zastrowi sillemi for different parameters by residue deposit method and diet contamination method in the same and subsequent generation. Lowest larval mortality was obtained in Bacillus thuringiensis(17.76%) followed by Metarhizium anisopliae(28.64%) in residue deposit methods. While in case of diet contamination, Lecanicillium lecani registered 10.00% larval mortality followed by Metarhizium anisopliae(11.33%). Morerover, in both the methods, highest mortality was observed in Fipronil (82.67%) in residue deposit and 89.33%-in diet contamination methods followed by Azadirachtin. With respect to egg length and egg period Bacillus thuringiensis was comparable with the untreated check (distilled water) as evident from residue method. In case of diet contamination method, Lecanicillium lecani had least influence on egg causing maximum length of 1.64mm and maximum egg duration of 3.27days.Azadirachtin and fipronil caused detrimental effect of egg affecting egg size and egg period. With respect to 3rd instar larval size and larval duration Lecanicillium lecani and Bacillus thuringiensis had least effect and comparable with that of distilled water treatment. Similarly Bacillus thuringiensis had least effect on larval biology followed by Lecanicillium lecani comparing to other treatments as evident from residue deposit method. In case of 3rd instar larval size and larval duration, maximum record was observed in Bacillus thuringiensis(5.67mm larval length and 9.80days larval duration) followed by Lecanicillium lecani (5.58mm larval length and 9.59 days larval duration) indicating that in case of residue deposit method, Bacillus thuringiensis had least effect on larval biology followed by Lecanicillium lecani comparing to other treatments. In diet contamination method, maximum larval length and larval duration was recorded in Lecanicillium lecani(larval length-5.68mm, larval duration-9.85 days) followed by Metarhizium anisopliae. Pupal size in both the methods was highest in Lecanicillium lecani (3.10mm in residue deposit and 3.13mm in diet contamination methods) followed by Metarhizium anisopliae (3.06mm in residue deposit and 3.10mm in diet contamination methods). Among the treatments Bt(6.77days) and Lecanicillium lecani (6.61days) gave longest pupal duration (pupal stage)and comparable with the untreated control . Adult size (length and breadth) in residue deposit method for male and female were recorded maximum in Bt treatment(8.26mm and 9.50mm-length, 1.39mm and 1.84mm-breadth) than other treatments whereas in diet contamination method, maximum length was found in Lecanicillium lecani (male-8.56mm and female-9.54mm) and maximum breadth was found in both Lecanicillium lecani and Metarhizium anisopliae (1.41mm) for male and Bacillus thuringiensis (1.85mm) for female. Duration of adult male and female in residue deposit method maximum duration was recorded in Bacillus thuringiensis(31.09 days and 39.11days respectively) whereas in diet contamination method, maximum duration was recorded in Lecanicillium lecani (30.47 days in male and 37.80 days in female ). Maximum Fecundity of adult female was recorded in Bacillus thuringiensis(331.42) in case of residue deposit method and in Lecanicillium lecani (311.67) in case of diet contamination method. In both the methods the chemical check fipronil recorded lowest fecundity indicating that this treatment had influence the fecundity in subsequent generation. While considering the over performance of different biopesticides, Lecanicillium lecani, Metarhizium anisopliae and Bacillus thuringiensis were found relatively less toxic and safer for Chrysoperla zastrowi sillemi (Esben-Peterson)
