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University of Agricultural Sciences, Bengaluru

University of Agricultural Sciences Bangalore, a premier institution of agricultural education and research in the country, began as a small agricultural research farm in 1899 on 30 acres of land donated by Her Excellency Maharani Kempa Nanjammanni Vani Vilasa Sannidhiyavaru, the Regent of Mysore and appointed Dr. Lehmann, German Scientist to initiate research on soil crop response with a Laboratory in the Directorate of Agriculture. Later under the initiative of the Dewan of Mysore Sir M. Vishweshwaraiah, the Mysore Agriculture Residential School was established in 1913 at Hebbal which offered Licentiate in Agriculture and later offered a diploma programme in agriculture during 1920. The School was upgraded to Agriculture Collegein 1946 which offered four year degree programs in Agriculture. The Government of Mysore headed by Sri. S. Nijalingappa, the then Chief Minister, established the University of Agricultural Sciences on the pattern of Land Grant College system of USA and the University of Agricultural Sciences Act No. 22 was passed in Legislative Assembly in 1963. Dr. Zakir Hussain, the Vice President of India inaugurated the University on 21st August 1964.

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2012 - 201734
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Subject: Plant Pathology × End date: 2017 × Start date: 2012 × Thesis Type: Ph.D ×
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Now showing 1 - 9 of 34
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    ThesisItemOpen Access
    STUDIES ON ANTHRACNOSE DISEASE OF FIELD BEAN (Lablab purpureus L.) CAUSED BY Colletotrichum lindemuthianum (Sacc. & Magnus) Lams. Scri.
    (University of Agricultural Sciences GKVK, Banglore, 2012-08-01) MANJUNATH, , B.; NAGARAJU
    No Abstract
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    ThesisItemOpen Access
    STUDIES ON ETIOLOGY AND MANAGEMENT OF BETELVINE (Piper betle L.) WILT [Fusarium solani (Mart.) Sacc.]
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU, 2017-12-27) SOMANING NARAYANA, SHANKARANAVAR; SOMASEKHARA, Y. M.
    Betelvine (Piper betle L.) wilt [Fusarium solani (Mart.) Sacc.] is threatening disease in Karnataka due to severe wilting of the plants. Survey revealed that, the highest incidence of wilt in Ramanagar district (33.58%) followed by Hassan (27.42%) and Chikkaballapur (23.05%), whereas lowest wilt incidence in Kolar district (13.25%). Fungus isolated from infected roots and proved pathogenicity, and pathogen produced abundant micro and macro conidia, along with terminal and intercalary chlamydospores in the mycelium. Maximum radial growth as well as mycelial dry matter weight of the pathogen was found in Nash and Snyder’s medium on solid and in liquid form, respectively. In vitro evaluation of fungicides revealed that maximum inhibition of pathogen was found in tebuconazole (91.30%) and tebuconazole + trifloxystrobin (89.81%) followed by carbendazim + mancozeb (88.15%), carbendazim (85.74%) and propiconazole (83.89%). Similarly, Trichoderma harzianum (Th-55) (85.00%) and Bacillus subtilis (P-24) (72.59%) resulted in maximum inhibition of the pathogen in vitro. Under field conditions tebuconazole and propiconazole treated vines showed significantly less wilt incidence of 22.22 and 30.56 per cent, respectively and tebuconazole + trifloxystrobin (44.44%) and carbendazim + mancozeb (47.22%) were on par. Whereas, soil population of the pathogen was significantly reduced in tebuconazole (1.53 ×103 cfu/g of soil) and propiconazole (2.14×103 cfu/g of soil) treated soil. T. harzianum (Th-55) (22.22%) was most effective bio-agent in reducing wilt incidence in comparison with the initial disease level followed by B. subtilis (27.78%), B. subtilis var. amyloliquefaciens (27.78%) and T2+T3+T4+T5 (27.78%) which were on par with each other. The soil population of F. solani was significantly reduced in T. harzianum (Th-55) (2.31 ×103 cfu/g of soil) and T2+T3+T4+T5 (3.57 ×103 cfu/g of soil) treated soil. The fungicides viz., tebuconazole, propiconazole and the antagonist T. harzianum (Th-55) are useful in reducing betelvine wilt disease.
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    ThesisItemOpen Access
    MOLECULAR VARIABILITY AND INTEGRATED MANAGEMENT OF PAPAYA RINGSPOT VIRUS (PRSV)
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU, 2017-09-28) ANIL, PAPPACHAN; Nagaraju, N.
    Papaya Ringspot Virus (PRSV) is posing a major threat to papaya cultivation throughout India by rendering orchards economically unproductive. Survey conducted in 2014-15 revealed that 100 per cent PRSV incidence was observed at some locations of Bangalore rural and Bangalore urban districts of Karnataka, while highest average incidence was recorded at Ramanagara (82 %). In Andhra Pradesh, Kadapa district recorded highest average disease incidence of 70 per cent, while in Telangana, 24 per cent incidence of PRSV was observed in Hyderabad. In Kerala PRSV incidence was highest in Kottayam (77 %) and in Tamil Nadu, highest average incidence of 70 per cent was observed at Coimbatore. Comparison of P1 proteinase gene of PRSV deposited in NCBI GenBank revealed that nucleotide identity of South Indian PRSV isolates ranged from 87 to 72 per cent. None of the fifteen cultivated papaya varieties was found to possess resistance to PRSV both under glasshouse and field conditions. Extracts of Acorus calamus (5 %), Boerhavia diffusa (5 %), Kappaphycus alvarezii (KH-1 %), Eucheuma spinosum (SH-1 %) and Silicic acid (1 %) showed significant inhibitory effect on PRSV. Silver nanoparticles (60 to 100 nm) were prepared by green synthesis process using neem (Azadirachta indica) leaf extract. The extract of B. diffusa (5 %), colloidal Silver nanoparticles (100 ppm), Silver nanoparticles (50 ppm) prepared by green synthesis process and K. alvarezii (LBS3-1 %) showed significant inhibitory effect on PRSV multiplication both under field and glasshouse conditions. Adoption of integrated disease management module (III) a combination of maize (South African tall) as barrier crop, use of silver reflective mulch row cover and spraying with extract of A. calamus (5 %), K. alvarezii extract (KH-1 %) and insecticide imidacloprid (0.05 %) at monthly interval resulted in 142.39 per cent increase in yield over control with highest return per rupee invested (1.91).
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    ThesisItemOpen Access
    MOLECULAR CHARACTERIZATION OF TOBACCO STREAK VIRUS CAUSING SUNFLOWER NECROSIS DISEASE AND ITS INTEGRATED MANAGEMENT
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU, 2017-09-18) MANJUNATH, S. HURAKADLI; Rangaswamy, K. T.
    Sunflower necrosis disease (SND) caused by tobacco streak virus (TSV) and transmitted by thrips is a major constraint for sunflower cultivation in India. Survey conducted to assess the SND incidence in major sunflower growing districts of Karnataka during 2015-17 revealed that, SND incidence and mean thrips population ranged from 0 to 28.57 per cent and 0 to 5.4 thrips per plant, respectively. The DAC-ELISA deployed to detect TSV in weed hosts (21 species) and thrips species (Thrips palmi, Frankliniella schultzei, Scirtothrips dorsalis). Eight weed species (Parthenium hysterophorus, Euphorbia geniculata, Abutilon indicum, Malvastrum coromandelianum, Acanthospermum hispidum, Phyllanthus niruri, Stachytarpheta indicum and Galinsoga parviflora) and T. palmi tested positive for the presence of TSV. The virus causing SND was identified by RT-PCR using newly designed RNA1, RNA2 and RNA3 specific primers which yielded 890, 765 and 717 bp amplicons, respectively. The sequences of GKVK isolate viz., RNA1 gene with TSV-Kad and TSV-Okra, RNA2 gene with TSVPumpkin and TSV-FL1307, and RNA3 gene with TSV-Gulbarga and TSV-CPKAR shared 99 per cent nucleotide similarity. Based on nucleotide sequence similarity and phylogenetic relatedness, the GKVK-isolate identified as a strain of TSV prevalent in India. The stability and integration of coat protein and nptII genes in T5 generation transgenic plants of sunflower genotypes RHA 95-C-1 and NSFH-1 was confirmed by PCR analysis. Expression of coat protein gene was confirmed by RT-PCR and ELISA. For the management of SND, an integrated approach comprising of maize border crop around field (15 days prior to sowing of sunflower) and seed treatment with imidacloprid 600 F.S. @ 5 mL/kg of seeds and spray of defense inducing molecule (oligocarranegen) @ 4 mL/L along with foliar application of fipronil 5% S.C @ 1.5 mL/L at 15, 30 and 45 DAS was found effective.
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    ThesisItemOpen Access
    BIOCHEMICAL BASIS OF RESISTANCE IN CHICKPEA (Cicer arietinum L.) AGAINST DRY ROOT ROT CAUSED BY Macrophomina phaseolina (Tassi) Goid. AND ITS MANAGEMENT
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU, 2016-12-12) JYOTHI, V.; Saifulla, M.
    Chickpea (Cicer arietinum L.), also known as Gram or Bengal gram, is the second most important pulse crop in the world, India accounting for 60 to 75 per cent of the world‟s chickpea production. It is known by a variety of names that includes, poischiche (French), homos (Arabic), chickpea (English), grao-de-bico (Portugese), garbanzo (Spanish), chana (Hindi, Punjabi, and Urdu) and kondaikadalai (Tamil). Chickpea seeds contain high quality easily digestible protein (25 %) and carbohydrates (20 %) making it an important source of protein for the vegetarians of the country and thus it is also called “Poor man‟s meat.” Chickpea is widely used either as grain or vegetable in Indian cuisine and an important source of vegetable protein. The origin of chickpea is thought to have been in South Eastern Turkey and neighbouring Northern Syria (Van der Maesen, 1972). It has since spread to many other geographical regions of the world because of its ability to grow in diverse environmental conditions. There are two main commercial types of chickpea, the “Desi” type with smaller and darker coloured seeds which may vary from yellow to black and the “Kabuli” type with large, smooth and light coloured seeds.
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    ThesisItemOpen Access
    EFFICACY OF COLLOIDAL SILVER PARTICLES AGAINST SELECTED PLANT PATHOGENS
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU, 2016-12-29) SHANTAMMA; Rangaswamy, K. T.
    Studies on efficacy of colloidal silver particles against late blight of potato and bacterial blight of pomegranate were carried out during 2014-16. Colloidal silver was synthesized by the ‘bottom up’ approach of wet chemical synthesis and analyzed by laser Dynamic Light Scattering (DLS). The particle size was in the range between 11.17 to 5186 nm with a mean diameter of 149.4 mm, of which 93.60 per cent particles measured 171.8 nm in diameter. The colloidal silver @ 500 ppm concentration was recorded (86.13 %) significantly maximum inhibition of Phytophthora infestans mycelia growth whereas @ 10 and 25 ppm completely inhibited Xanthomonas axonopodis pv. punicae. The physical incompatibility was noticed when colloidal silver combined with fungicides Cymoxanil 8 % + Mancozeb 64 % WP and Dimethomorph 50 % WP due to change in the pH (8) of mixed solution, but physical compatibility was observed when colloidal silver particles antibiotic Streptocycline (Streptomycin sulphate 90 % + Tetracycline hydrochloride 10 %). The pH of the mixed solution was acidic (5.6). Phytotoxicity was recorded at 750 ppm of colloidal silver alone and in combinations with fungicides and antibiotic on both potato and pomegranate. In field studies, 500 ppm of colloidal silver in combination with 0.2 per cent of Cymoxanil 8 % + Mancozeb 64 % recorded maximum reduction of late blight severity as compared to either colloidal silver alone and its combination with Dimethomorph 50 % WP @ 0.20 per cent. No significant enhancement of inhibitory activity was observed when applied with antibiotic Streptocycline against pomegranate bacterial blight. The increased activity of defense enzymes viz., PO, PPO, PAL, chitinase, total phenols and higher accumulation of chlorophyll was observed in late blight infected potato and pomegranate plants upon treatment with either colloidal silver alone or in combination with fungicides/antibiotics.
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    ThesisItemOpen Access
    MOLECULAR CHARACTERIZATION OF TOSPOVIRUSES AND IDENTIFICATION OF HOST RESISTANCE IN CAPSICUM SP.
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU, 2016-12-27) PAVITHRA, B. S.; Krishna Reddy, M.
    Survey was conducted in different districts of Karnataka, Andhra Pradesh and Tamil Nadu indicated GBNV incidence of 3 to 21 per cent and the infected plants exhibited chlorotic and necrotic ringspot symptoms. The virus was transmitted mechanically and infects systemically to groundnut, beans, soybean, pea, watermelon, potato, marigold and local lesions on cowpea, tobacco, datura, petunia, chenopodium and sunhemp. The electron microscopic observation of virus infected chilli samples showed presence of spherical particles of 80-120 nm in diameter. In DAC-ELISA, the virus showed positive reaction to GBNV specific antisera. Using overlapping primers specific to GBNV, complete genome was amplified and sequenced for three isolates of GBNV. The S RNA has 3057 nt length with two ORFs (NSs and N gene) separated by intergenic region (IGR), the M RNA contains 4815 to 4817 nt in length with two ORFs (NSm and Gp) separated by IGR and the L RNA of 8911 nt has single ORF which codes for RNA dependent RNA polymerase. Among 102 germplasm screened, eight genotypes are highly resistant, eight genotypes are resistant, seven genotypes are moderately resistant. Using RGA primers specifically amplified a DNA fragment of 0.5kb from resistant chilli genotypes but not from susceptible genotypes. After cloning and sequencing, out of 81 clones, 60 clones showed 69.5 to 100 per cent similarities with known RGAs. Eighteen clones of Non TIR-NBS-LRR type of RGAs had similar homology with putative late blight resistance genes of Nicotiana tabacum, N. tomentosiformis, Solanum lycopersicom, S. pennelli, S. tuberosum and PVr9 potyvirus resistance protein. Twelve clones of TIR-NBSLRR type of RGAs had similar homology with TMV resistance protein N like gene of Capsicum annuum, Nicotiana tabacum, N. tomentosiformis, Solanum aculeatissimum, S. bulbocastanum, S. esculentum, S. pennelli and S. tuberosum. RGAs identified will be useful in marker-assisted breeding for GBNV resistance in chilli.
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    ThesisItemOpen Access
    IN VITRO AND FIELD EVALUATION OF DIFFERENT SILICON SOURCES AGAINST SELECTED DISEASES IN TOMATO (Solanum lycopersicum L.)
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU, 2016-12-27) KEDARNATH; Rangaswamy, K. T.
    Studies on evaluation of different silicon sources against major diseases of tomato viz., early blight, late blight, powdery mildew and bacterial wilt were carried out during 2014-16. The studies revealed that, silicon sources inhibited the growth of Alternaria solani (15.67 to 87.50 %), Phytophthora infestans (1.12 to 90.37 %), Oidium neolycopersici (67.40 to 100 %) and Ralstonia solanacearum (0.08 to 2.44 OD @ 600 nm) at different concentrations under in vitro condition. Silixol plus @ 4 ml L-1 found most effective in inhibiting A. solani, P. infestans and O. neolycopersici, whereas, OSAB @ 4 ml L-1 against R. solanacearum under in vitro condition. OSAB @ 4 ml L-1 as foliar spray three times at 15 days intervals effectively reduced the disease severity of powdery mildew (55.50 %) under pot culture study, late blight (50.43 %) and early blight (33.15 %) under field condition whereas, OSAB @ 4 ml L-1 as seedling dip followed by soil application (10 and 20 DAP) reduced the bacterial wilt incidence by 77.33 per cent in pot culture study and 67.80 per cent under field condition besides reducing the soil and rhizosphere population of R. solanacearum at both flowering and harvesting stage. Seedling dip, soil and foliar application of OSAB and Silixol plus @ 4 ml L-1 also increased plant height, number of branches, fresh and dry shoot weight, silicon content, yield and chlorophyll content (SPAD values) besides increased activity of defense related enzymes (peroxidase, polyphenol oxidase, phenylalanine ammonia lyase, β-1, 3 glucanase, chitinase, soil urease and sucrose activity) during post application.
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    ThesisItemOpen Access
    INVESTIGATION ON GANODERMA WILT OF COCONUT AND ARECANUT WITH RESPECT TO PATHOGEN VARIABILITY AND DISEASE MANAGEMENT
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU, 2016-10-23) PALANNA, K. B.; Narendra, T.
    The incidence of Ganoderma wilt of coconut and arecanut was maximum (19.32 %) in Tumkur district followed by Chitradurga and Hassan in southern Karnataka. Diseased root bits and sporocarp were good source(s) for isolation of Ganoderma with Potato Dextrose Agar and Oat Meal Agar that supported highest radial growth and biomass production. Of the nine Ganoderma isolates, CG11 recorded maximum disease severity index (62.50 DSI) in coconut. However, Arecanut isolate AG9 recorded maximum DSI (75) and designated as most virulent isolates. The pileus shape, pileus thicknes, stipe length, stipe attachment and colour of pore surface of sporocarps varied greatly in coconut and arecanut. The molecular characterization of Ganoderma through DNA amplification resulted in 650bp in all isolates tested. The phylogenetic analysis of TIS sequence with other known species of Ganoderma through NCBI web proved that the isolates were related to Ganoderma sp. with 80-100 per cent identity and shown close relationship with India, China and Sri lanka Ganoderma species. Bengalgram, redgram and bhendi were found indicator plants for early detection of disease. Cent per cent inhibition of mycelial growth of Ganoderma was recorded in Tebuconazole, Propiconazole, Hexaconazole, Kitazin, Propineb and combi-products viz., Hexaconazole + Zineb, Hexaconazole + Captan, Fenmidone + Mancozeb, Tebuconazole + Trifloxystrobin WG at >250ppm. Urea recorded 67.34 and 46.89 per cent inhibition against CG14 and AG7 respectively. However, chemical fertilizers supported the development of T viride at lower concentration (250 ppm). ZnSo4 and Gypsum recorded 52.53 and 7.42 per cent inhibition of biocontrol agent at 1000 ppm; MgSo4 supported the growth and sporulation of biocontrol agent. Tebuconazole root feeding in coconut @1.5 ml in 100 ml water/palm at quarterly interval + Soil application of 5 kg neemcake enriched with T. viride/ palm/ half yearly + Pseudomonas fluorescens (talc formulated) @ 50 g/palm/ half yearly + Soil drenching with half yearly 1per cent Bordeaux mixture @ 20 l/palm reduced disease index and which accounted 76.41per cent reduction over in control with maximum nut yield. Similarly, the treatment in arecanut recorded the least increase of 7.39 disease index, which accounted 55.22 per cent reduction over control with maximum nut yield.