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2009 - 200912020 - 20244
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Subject: Agricultural Entomology × Start date: 2009 ×
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    ThesisItemOpen Access
    STUDY ON THE DYNAMICS OF INSECT PESTS OF SUGARCANE IN THE TARAI REGION OF UTTARAKHAND AND EVALUATION OF VARIOUS SUGARCANE GERMPLASM AGAINST MAJOR INSECT PESTS
    (G. B. Pant University of Agriculture & Technology, Pantnagar-263145, 2023-07) Tanveer, Saba; Maurya, R. P.
    Study on the population dynamics of insect pests and varietal screening of sugarcane was carried out at N.E.B. Crop Research Centre, G. B. Pant University of Agriculture and Technology, Pantnagar during 2022-23. During study, a total of eight insects viz. early shoot borer, top shoot borer, internode borer, pyrilla, mealybugs, whitefly, ash weevil and grasshopper were found infesting sugarcane. The maximum percent infestation by early shoot borer (26.67 percent) was observed in the second fortnight of June, top borer (36.67 percent) activity was reported maximum in first fortnight of September. The internode borer (26.67 percent) and pyrilla (3.03 eggs, 5.50 nymphs 6.23 adults/leaf) maximum activity was recorded in the month of November and December, respectively. Peak activity of whitefly (2.03/3 leaves) and mealybug (49 percent) was observed in the month of October and November, respectively. Correlation studies revealed that minimum temperature positively correlated with early shoot borer infestation (r = 0.696*) while negatively correlated with infestation of internode borer (r = - 0.709*) and pyrilla egg population (r = - 0.614**); maximum temperature had inverse effect on internode (r = - 0.677*) and pyrilla egg population (r = -0.474*). The morning humidity and afternoon humidity had significant positive correlation with internode borer (r = 0.763), mealybug (r = 0.492*), top borer (r = 0.632*) and ash weevil infestation (r = 0.708*). Rainfall had a positive impact on early shoot borer infestation (0.749*). The activity of natural enemies namely, coccinellids (0.27 adults/plant) and spider (1.20/plant) were found to be maximum in second fortnight of December and August, respectively. Cheiloneurus sp., an egg parasitoid was reported and found parasitizing the eggs of pyrilla from second fortnight of August, 2022 till first fortnight of January and maximum parasitisation was observed in the first fortnight of November (73 percent). An ectoparasitoid F. melanoleuca marked its appearance in field in first fortnight of July and reached maximum in the second fortnight of October (2.30 cocoons/leaf) and highest parasitization of nymph (58.33 percent) and adults (51 percent) of pyrilla was observed in second fortnight of October, respectively whereas, no record of natural enemies of borers associated with sugarcane was found. Evaluation of sugarcane germplasm for their reaction against borer complex and sucking pests was conducted with ten germplasm and five checks. The results of the screening revealed that germplasm CoPant 12221 was found least susceptible against all borers, pyrilla and mealybug infestation followed by CoPant 13224 and CoPant 12226. Other germplasm viz. CoPant 17223 and CoPant 19221 were found moderately susceptible against borers and sucking insect pests whereas, CoPant 17224 and CoPant 18222 were found to be least susceptible only against sucking pests. All the germplasms were found to be least susceptible against internode borer and mealybug infestation. Biophysical and biochemical studies were also performed for determining resistance traits in germplasm against borers and sucking pests. The results revealed that at 90 DAP, leaf number showed significant positive correlation with early shoot borer infestation (r = 0.609*) and with pyrilla (r = 0.644**), at 180 DAP leaf width was significantly correlated with top borer infestation (r = 0.767**) and leaf number showed positive correlation with pyrilla (r = 0.614*) and mealybug (r = 0.519*). At 270 DAP, leaf number was found to be positively correlated with pyrilla infestation (r = 0.610*). The percent infestation of early shoot borer was significant positively correlated with total soluble carbohydrates (r = 0.609*). Those germplasm that incurred resistance showed these traits such as narrower leaf width, low number of leaves, wider leaf angle, higher levels pf antioxidant and phenol and decreased total carbohydrate content. These characteristics effectively led to reduced insect pests attack.
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    ThesisItemOpen Access
    STUDY ON THE DYNAMICS OF INSECT PESTS OF SUGARCANE IN THE TARAI REGION OF UTTARAKHAND AND EVALUATION OF VARIOUS SUGARCANE GERMPLASM AGAINST MAJOR INSECT PESTS”
    (G. B. Pant University of Agriculture & Technology, Pantnagar-263145, 2023-07) Tanveer, Saba; Maurya, R. P.
    Study on the population dynamics of insect pests and varietal screening of sugarcane was carried out at N.E.B. Crop Research Centre, G. B. Pant University of Agriculture and Technology, Pantnagar during 2022-23. During study, a total of eight insects viz. early shoot borer, top shoot borer, internode borer, pyrilla, mealybugs, whitefly, ash weevil and grasshopper were found infesting sugarcane. The maximum percent infestation by early shoot borer (26.67 percent) was observed in the second fortnight of June, top borer (36.67 percent) activity was reported maximum in first fortnight of September. The internode borer (26.67 percent) and pyrilla (3.03 eggs, 5.50 nymphs 6.23 adults/leaf) maximum activity was recorded in the month of November and December, respectively. Peak activity of whitefly (2.03/3 leaves) and mealybug (49 percent) was observed in the month of October and November, respectively. Correlation studies revealed that minimum temperature positively correlated with early shoot borer infestation (r = 0.696*) while negatively correlated with infestation of internode borer (r = - 0.709*) and pyrilla egg population (r = - 0.614**); maximum temperature had inverse effect on internode (r = - 0.677*) and pyrilla egg population (r = -0.474*). The morning humidity and afternoon humidity had significant positive correlation with internode borer (r = 0.763), mealybug (r = 0.492*), top borer (r = 0.632*) and ash weevil infestation (r = 0.708*). Rainfall had a positive impact on early shoot borer infestation (0.749*). The activity of natural enemies namely, coccinellids (0.27 adults/plant) and spider (1.20/plant) were found to be maximum in second fortnight of December and August, respectively. Cheiloneurus sp., an egg parasitoid was reported and found parasitizing the eggs of pyrilla from second fortnight of August, 2022 till first fortnight of January and maximum parasitisation was observed in the first fortnight of November (73 percent). An ectoparasitoid F. melanoleuca marked its appearance in field in first fortnight of July and reached maximum in the second fortnight of October (2.30 cocoons/leaf) and highest parasitization of nymph (58.33 percent) and adults (51 percent) of pyrilla was observed in second fortnight of October, respectively whereas, no record of natural enemies of borers associated with sugarcane was found. Evaluation of sugarcane germplasm for their reaction against borer complex and sucking pests was conducted with ten germplasm and five checks. The results of the screening revealed that germplasm CoPant 12221 was found least susceptible against all borers, pyrilla and mealybug infestation followed by CoPant 13224 and CoPant 12226. Other germplasm viz. CoPant 17223 and CoPant 19221 were found moderately susceptible against borers and sucking insect pests whereas, CoPant 17224 and CoPant 18222 were found to be least susceptible only against sucking pests. All the germplasms were found to be least susceptible against internode borer and mealybug infestation. Biophysical and biochemical studies were also performed for determining resistance traits in germplasm against borers and sucking pests. The results revealed that at 90 DAP, leaf number showed significant positive correlation with early shoot borer infestation (r = 0.609*) and with pyrilla (r = 0.644**), at 180 DAP leaf width was significantly correlated with top borer infestation (r = 0.767**) and leaf number showed positive correlation with pyrilla (r = 0.614*) and mealybug (r = 0.519*). At 270 DAP, leaf number was found to be positively correlated with pyrilla infestation (r = 0.610*). The percent infestation of early shoot borer was significant positively correlated with total soluble carbohydrates (r = 0.609*). Those germplasm that incurred resistance showed these traits such as narrower leaf width, low number of leaves, wider leaf angle, higher levels pf antioxidant and phenol and decreased total carbohydrate content. These characteristics effectively led to reduced insect pests attack.
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    ThesisItemOpen Access
    SCREENING OF BLACKGRAM & GREENGRAM GERMPLASM AND COMBINED EFFECT OF Baciillllus tthuriingiiensiis ((Berlliiner)) WITH SOME SECONDARY PLANT METABOLITES AGAINST Spodopttera lliittura ((Fabriiciius))
    (G. B. Pant University of Agriculture & Technology, Pantnagar-263145, 2022-08) Gejo,Tribikram; Purwar, J. P.
    The present investigations were carried out to study the screening of blackgram and greengram germplasm under field conditions at the Norman E. Borlaug Crop Research Centre during the kharif season of 2021. Compatibility of B. thuringiensis with some secondary plant metabolites and combined effect of B. thuringiensis with some secondary plant metabolites against S. litura (Fab.) infesting blackgram and greengram were conducted in PGR Lab, Department of Entomology, College of Agriculture, G. B. Pant University of Agriculture and Technology, Pantnagar, Uttrakhand. On the basis of data recorded among various entries DAFTRI 471 & JLPU 819-18 were found superior against whitefly and IPU 2-43, RVSTU 21-1& RUG 59 were found tolerant against M. distalis & Jassids respectively, whereas PU 1706 found superior against defoliators in blackgram. In case of greengram MH 1468, MH 1857, PUSA M 21-71 were found superior against jassid & thrips, whitefly, defoliators respectively. Compatibility study of B. thuringiensis with different secondary plant metabolites indicated that α- pinene, saponin, maleic acid and oxalic acid were found compatible with B. thuringiensis at all the concentration, while quercetin was found incompatible. Bio assay study was carried out to evaluate the combined effect of B. thuringiensis with some secondary plant metabolites against 6 days old larvae of S. litura (Fab.). All the combinations showed higher dose-mortality response than the sole treatment of B. thuringiensis or the secondary plant metabolites. The combination of the secondary plant metabolites with B. thuringiensis showed 1.06–1.30 fold increase in toxicity of secondary plant metabolites over sole treatment.
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    ThesisItemOpen Access
    STUDIES ON MAJOR INSECT PESTS AND DEFENDER FAUNA IN VARIOUS BITTER GOURD VARIETIES/LINES GROWN IN OPEN AND PROTECTED CONDITIONS
    (G. B. Pant University of Agriculture & Technology, Pantnagar-263145, 2024-02-01) Kumar, Nilesh; Srivastava, R. M.
    The present research work “STUDIES ON MAJOR INSECT PESTS AND DEFENDER FAUNA IN VARIOUS BITTER GOURD VARIETIES/LINES GROWN IN OPEN AND PROTECTED CONDITIONS” is based on population studies of insect pests and defender/natural enemies fauna in bitter gourd crop in open as well as protected conditions and their correlation with various abiotic factors. Various varieties/lines of bitter gourd have been screened against insect pests of bitter gourd and categorized as low, moderate and high tolerance levels. During the investigation, it has been find out that population of insect pests were observed from 12th SMW to 24th SMW. The peak incidence of all insects i.e., fruit fly (20th SMW), aphid (18th SMW), jassid (15th SMW), whitefly (18th SMW), thrips (18th SMW) and semilooper (17th SMW) was witnessed from the fourth week of April to third week of May. Population of insect pests was compared in open and protected condition. It was found that population level of all pests was higher in open condition except whitefly, which was found higher in protected/green house condition. Defenders fauna was also studied. Thirty five genotypes of bitter gourd was screened out against infestation of fruit fly (B. cucurbitae) and categorized as low, moderate and higher tolerance levels. Three cultivars were found highly tolerant against infestation of fruit fly whereas six were resistant, nineteen moderately resistant and eight were susceptible. The current study will be helpful in developing integrated pest management strategies for bitter gourd crop in view of resistance cultivars, population management and conservation of defender fauna.
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    ThesisItemOpen Access
    Insect pest complex of tea [Camellia sinensis (L.) O. Kuntze] and their natural enemies in Uttarakhnd
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2009-01) Sharma, Rajesh Kumar; Bisht, R.S.
    Extensive surveys carried out during 2005-2008 revealed the occurrence of 58 arthropods pests associated with tea crop. All the species appeared new to Uttarakhand. Significantly, the class Insecta has been found as the predominant group of arthropods (56 species) over Arachnida (2 species) both qualitatively and quantitatively. Considering the species spectrum, the order Hemiptera and Orthoptera has been reported as the most prevalent insect order (14 species of each), followed by Lepidoptera and Coleoptera (10 species of each), Thysanoptera (5 species), Isoptera (2 species) and Diptera (1 species). The subtropical zone is represented highest number of 56 species of arthropods in comparison to tropical zone where only 23 species associated with tea. The seasonal incidence and relative abundance of these arthropods in tropical and subtropical localities has also been discussed in the thesis. Out of 58 species of arthropods reported Toxoptera aurantii (Boyer.), Thrips hawiiensis (Morgan), T. flavus Schrank, Caloptilia theivora Walsm.and Xenocatantops humilis Serville have been identified as the predominant species and therefore considered as the pests of major importance. A total of 18 species of natural enemies of tea pests have been reported for the first time from this region. The subtropical zone represented a total of 14 species and 04 species of predators and parasitoids respectively. In contrast to tropical zone where only 7 predators were recorded. The distribution, relative abundance along with prey/ host relation of these natural enemies in different phytogeographical locations has been also incorporated. The population density and seasonal fluctuations in population of some major insect pests of tea viz., tea aphid, tea thrips, Grasshoppers, and leaf roller on 5 commonly growing germplasms of tea viz., T-78, BSS-449, AV-2, UPASI-9 and Kangra Jat have been studied at Kausani with respect to different plucking seasons. The congenial seasons for tea aphid, thrips and leaf roller has been observed during Easter and Summer plucking seasons whereas for grasshoppers it was during autumn plucking season. Seven categories of pests attacking tea plantation have been identified on the basis of their nature of damage viz., sap suckers, defoliators, leaf rollers, leaf folders, leaf miners, root feeders and borers. The highest number of 22 species have been reported as sap suckers followed by defoliators (17 species), root feeders (11 species), leaf folders (4 species), borers (2 species), leaf roller (1 species) and leaf miner (1 species). Field experiments have been carried out to screen the tea germplasm viz., T - 78, BSS - 449, AV - 2, UPASI - 9, BSS - 379, RR - 17/44, P – 383 and P - 312 against some major insect pests of tea (tea aphid, tea thrips, Grasshoppers, and leaf roller) for resistance. The germplasms viz., BSS-379, RR-17/44, P-383 and P-312 have been identified to be resistant for major pests of tea and therefore may be promoted for the betterment of the tea industry in Uttarakhand. The thesis also incorporates the results of bioefficacy of some local plant extracts against the tea aphid, T. aurantii and tobacco caterpillar, Spodoptera litura Fabr. Out of 10 plant extracts tested in laboratory the extracts of Giardinia heterophylla, Zanthoxylum atmatum and Agave americana have beeb found to exhibit promising effect against the tea aphid and tobacco caterpillar. Laboratory experiment on the feeding propensity of the larvae of the syrphid, Episyrphus balteatus de Geer and larvae and adults of Coccinella septempunctata L. on third instar nymphs of tea aphid have been conducted. It has been observed that the larvae of these predators destroyed more number of aphids as compared to the adult of C. septempunctata (average feeding propensity 46.40, 33.20 and 29.96 third instar nymphs/ 24 hours respectively). the thesis also incorporates the results of per cent parasitisation by hymenopteran larval parsitoids on tea leaf roller, C. theivora and tea tortix, Homona coffearia at subtropical location, Kausani. Feeding propensity of common grasshopper, X. humilis observed in laboratory revealed that the insect consumed on an average of 0.550 mg of tea foliage/ 24 hours.