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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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201919
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Subject: Plant Pathology × End date: 2019 × Start date: 2019 × Type: Thesis ×
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Now showing 1 - 9 of 19
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    ThesisItemOpen Access
    STUDIES ON PYTHIUM SOFT ROOT ROT DISEASE OF MULBERRY
    (University of Agricultural Sciences, Bangalore, 2019-08-28) RAVICHANDRA; Y. M. SOMASEKHARA
    Mulberry crop affected by many diseases and threatening the mulberry cultivation. Recently, some of the mulberry gardens were infected with soft root rot disease with symptoms like withering and drying of leaves, mucilaginous matrix on bark of the roots resulting roots become soft and ultimately the plant showed epinasty and wilting. The soft root rot disease was observed in Agara (43.76 %), Kebre (32.57%), Thattekere (18.79%) and Gerehalli (13.58%) villages of Ramanagara district and Maddur (7.89 %), Halaguru (16.78 %) and Malavalli (6.58 %) of Mandya district. The pathogen Pythium sp. Was isolated from infected roots and identified based on morphological characters and proved pathogenicity. The maximum growth of the pathogen was found at 25 °C with pH 7. PDA (90 mm) and V-8 agar (90 mm) supported maximum growth of the pathogen. Among the fungicides evaluated in vitro condition Captan (86.29 %), Mancozeb + Metalaxyl, Carbendazim + Mancozeb, Fenamidone + Mancozeb, Azoxystrobin + Mancozeb (94.44 %), and Tebuconazole (100 %) were found effective. Among botanicals, neem extract (14.02 %) had highest inhibition of the pathogen. Trichoderma viride-1 (95.54 %) and Bacillus pumilis (58.88 %) were effective in vitro conditions. The bio-agents T. viride-1 and T. viride-2 found effective in glasshouse and field conditions. The effective fungicides Mancozeb + Metalaxyl (0.1 %) and Captan (0.2 %) reduced disease under field conditions up to 31.96 and 27.45 per cent, respectively. These fungicides, botanicals and bio-agents can be exploited for the management of soft root rot disease of mulberry.
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    ThesisItemOpen Access
    MANAGEMENT OF Alternaria LEAF BLIGHT OF SUNFLOWER USING COMPOST TEA AND SEAWEED FORMULATION
    (UNIVERSITY OF AGRICULTURAL SCIENCES, GKVK, BENGALURU, 2019-08-13) SHADAB, M. KHATIB
    Sunflower crop suffers from many diseases of which Alternaria blight has been considered as a potentially destructive disease. In vitro evaluation of compost tea revealed that maximum inhibition of A. helianthi was recorded in compost tea at 25 per cent (60.50%) followed by compost tea at 20 per cent (58.50%) and 15 per cent (53.80%). In field conditions, foliar spray of compost tea at the rate of 1:10 ratio at 30, 45 DAS and propiconazole at 1mlL-1 at 60 DAS increased the growth parameters like plant height (245.93 cm), stem girth (4.60 cm), number of leaves (9.35) and chlorophyll content (42.97). Foliar spray of compost tea with propiconazole was effective in controlling the Alternaria blight of sunflower with least disease severity (10.37%) and higher yield (2201.41 Kg ha1) which was on par with foliar spray of seaweed formulation (LBD-1) at 30, 45 DAS and propiconazole at 60 DAS with disease severity 12.32 per cent and seed yield of 1928.04 Kg ha-1. The defense enzymes such as superoxide dismutase (39.47 µg/50 per cent inhibition) and peroxidase (16.86 µg/ min/ mg protein) and also secondary metabolites such as phenolics (67.92 mg/g FW) and flavonoids (60.01 mg/g FW) increased in foliar spay of compost tea with propiconazole treated plants which resulted in least disease severity.
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    ThesisItemOpen Access
    ASSESSMENT ON THE IMPACT OF BANANA TISSUE CULTURE PLANTLETS ON MAJOR VIRAL DISEASES
    (UNIVERSITY OF AGRICULTURAL SCIENCES, GKVK BENGALURU, 2019-11-11) ANJALIDAS; PRAMEELA, H. A
    Tissue culture is a widely adopted technology for the propagation of virus-free banana plants. Survey for assessment of major viruses viz., BBTV, BSV, CMV and BBrMV in banana growing regions in southern Karnataka with tissue culture and sucker propagated banana gardens revealed the highest mean per cent incidence of BBTV (3.41%) followed by BBrMV (0.19%). The mean incidence of virus diseases was less (0.66%) in tissue culture gardens compared to gardens grown using suckers (2.65%). The mean incidence of virus disease was less (1.04%) in gardens grown using the main crop compared to ratoon established gardens (2.13%). Colorimetric detection for banana major viruses were standardized using nucleic acid fluorescent dyes viz., SYBR Green, Thiazole orange and VeriPCR to the PCR amplified product of BBTV, BSV, CMV and BBrMV infected samples produced bright green in case of SYBR green and VeriPCR whereas bright orange in case of thiazole orange. HNB dye changed the colour from pink to violet in infected samples of BBTV, BSV, CMV and BBrMV when applied before amplification. Standardization of HNB dye concentration for detection of BBTV indicated that 3mM @ 2µL, 5mM @ 2µL, 8mM @ 1µL and 2µL produced distinct violet with PCR product from infected samples and pink with healthy samples. HNB dye of 3mM at the rate of 2 µL was suitable for the detection of BBTV infected samples. The colorimetric detection methods in the current study are cost-effective and quick as they do not require the additional steps of electrophoresis and gel documentation
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    ThesisItemOpen Access
    DEVELOPMENT OF IDM MODULE FOR Tomato leaf curl virus AND ALTERNARIA BLIGHT IN TOMATO
    (UNIVERSITY OF AGRICULTURAL SCIENCES, GKVK, BENGALURU, 2019-08-17) ANUSHA KANCHAN, H. M.
    Tomato leaf curl disease (ToLCD) caused by Tomato leaf curl virus (ToLCV) and alternaria blight caused by Alternaria solani are the most threatening diseases for tomato production worldwide. Among the different plant defence activators and antibiotics tested, foliar application of silicic acid @ 4 mL L-1 and foliar application of LBD-1 @ 2 mL L-1 were found effective in reducing per cent incidence (PI), per cent disease index (PDI) of ToLCD and preference of whiteflies. The incidence and severity of ToLCD were reduced when the treatments were imposed to both source plants and healthy plants than the treatments imposed either to source plants or healthy plants. Amongst the different plant defence activators evaluated against A. solani, potassium phosphite @ 2 g L-1, silicic acid @ 4 mL L-1 and LBD-1 @ 2 mL L-1 were found effective in reducing growth of alternaria in vitro and in vivo. Two modules: M1 (newly designed module) and M2 (recommended package of practice) were evaluated for their field efficacy in reducing the incidence and severity of ToLCD and alternaria blight at two locations viz., Kadur and GKVK, Bengaluru. M1 module was consistently effective in reducing the incidence and severity of ToLCD, number of whiteflies per compound leaf and severity of alternaria blight throughout the study period at both the locations. Module M1 was found superior over M2 by recording highest gross and marketable yield of tomato.
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    ThesisItemOpen Access
    DETECTION AND CHARACTERISATION OF VIRUS CAUSING SUNFLOWER MOSAIC DISEASE
    (UNIVERSITY OF AGRICULTURAL SCIENCES, GKVK, BENGALURU, 2019-08-19) SANGEETA SABANNA BHAJANTRI
    Sunflower mosaic disease caused by Sunflower mosaic virus (SuMV) is one of the important viral diseases in sunflower. Sunflower plants inoculated mechanically with SuMV, exhibited mosaic symptoms followed by mottling, puckering, chlorotic rings, reduction in leaf lamina and stunted growth. Addition of 0.5 per cent sodium sulphite to phosphate buffer resulted in maximum transmission of virus. The SuMV was transmitted by Aphis gossypii with transmission efficiency of 16.00 to 24.00 per cent. The optimum pre-acquisition starvation period, acquisition feeding period and inoculation feeding periods required for successful transmission of SuMV was 60, 15 and 15 minutes respectively that resulted in 24.00 per cent transmission. In host range studies Nicotiana tabacum, Phaseolus vulgaris, Chenapodium amaranticolor and Gomphrena globosa exhibited chlorotic lesions and Cucumis sativus produced mosaic symptoms whereas, Datura stramonium and Solanum nigrum exhibited both mosaic and mottling symptoms. SuMV infected samples strongly reacted with potyvirus specific antisera in DAS ELISA. The virus was detected by RT-PCR using coat protein (CP) gene specific primers. The amplified product was ~500 bp in size. SuMV CP gene sequence analysis revealed that SuMV causing mosaic in GKVK, Bengaluru showed 98.95 per cent nucleotide identity with SuMV reported from USA and between 90-95 per cent with Sunflower chlorotic mottle virus (ScMoV) isolates reported from other countries. Out of the 11 genotypes screened under glasshouse condition, KBSH-41, KBSH-53 and AHT-5 were found to be resistant for SuMV. Among the 45 genotypes screened in field condition, only five genotypes exhibited mosaic symptoms.
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    ThesisItemOpen Access
    STUDIES ON FALSE SMUT [Ustilaginoidea virens (COOKE) TAKAHASHI] OF RICE
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU, 2019-12-14) SAVITHA, A. S.; NAGARAJA, A.
    False smut recently has become a threat for the successful production of rice. Roving survey of disease affected areas revealed that the disease severity ranged from 3.95 to 18.59 per cent and 3.89 to17.04 per cent during Kharif 2017 and 2018, respectively. Twenty isolates were obtained from five rice ecosystems of Karnataka and cultural variability of five selected representative isolates from each ecosystem revealed that the isolate Uv-12 recorded maximum colony diameter of 43.90 mm on potato sucrose agar (PSA) with typical yellowish white colony. Amongst 20 isolates of U. virens, isolate Uv-15 recorded maximum colony diameter of 70.00 mm on PSA media with raised flat, whitish to dark green colony and brown coloured chlamydospores. Maximum mycelial width of 6.37 μm was recorded in Uv-19 with the chlamydospore size of 28.82 to 90.16 μm. Scanning electron microscopy revealed hyaline, globose to irregularly rounded, ornamented chlamydospores with prominent spines. Among the ideal carbon and nitrogen sources, while Uv-1 recorded maximum growth on glycerol as carbon source, but Uv-12 did so on media supplemented with sodium nitrate. The higher number of chlamydospore germination was recorded in 2 per cent sucrose at 24 h of incubation. The DNA of 20 U. virens isolates was successfully amplified at 600-700 bp with ITS1 and ITS4 primers and the dendrogram drawn based on sequence data separated these isolates into two major clusters. The size of RAPD-PCR amplified products of U. virens isolates ranged from 290-3400 bp with Jaccard similarity coefficient values of 0.00 to 0.79. Foliar application of trifloxystrobin 25 % + tebuconazole 75 WG or tebuconozole 250 EC or azoxystrobin 25SC or propiconazole 25 EC at booting or at 50 % panicle emergence was effective for the management of false smut of rice.
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    ThesisItemOpen Access
    STUDIES ON DIVERSITY OF Sclerotium rolfsii Sacc. AND SCREENING OF GROUNDNUT COLLECTIONS AGAINST STEM ROT DISEASE
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU, 2019-09-06) SACHIN HAWALADAR; Jahir Basha, C. R.
    Studies on diversity of Sclerotium rolfsii Sacc. and screening of groundnut collections against stem rot disease were carried out during 2018-19 at the Department of Plant Pathology, University of Agricultural Sciences, Bangalore. Survey was conducted in major groundnut growing districts of Karnataka to know the prevalence of groundnut stem rot disease. The disease is prevalent in the entire groundnut growing areas surveyed with maximum (18.65 %) and minimum (11.63 %) incidence recorded in Bagalkot and Dharwad district, respectively. Ten isolates of Sclerotium rolfsii were collected from different locations of Karnataka and its variability were studied. The morphological and cultural characters of these isolates varied with respect to their growth rate, time taken to initiate sclerotia, size and weight of sclerotial bodies. Guledagudda isolate (SrB2) produced largest sclerotial body (2.33 mm) and Madhugiri isolate (SrT2) proliferated much faster compared to other isolates (12 days). Variability of these isolates were analyzed by amplifying and sequencing the ITS rDNA region. Among the ten isolates, seven isolates viz., SrY1, SrY2, SrD1, SrD2, SrC1 and SrT1 shared more per cent identity with Athelia rolfsii, two (SrB2 and SrC2) share more identity with Sclerotium delphini and two (SrB1 and SrT2) share identity with both Athelia rolfsii and Sclerotium dolphini. The groundnut genotypes were screened against the stem rot disease to identify the resistance source. Among the 31 genotypes screened in disease sick plot, 15 genotypes were moderately resistant with disease incidence ranging from 10.10-30.00 per cent, 15 genotypes were susceptible and one genotype TMV-2, was highly susceptible.
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    ThesisItemOpen Access
    STUDIES ON DIVERSITY OF Sclerotium rolfsii Sacc. AND SCREENING OF GROUNDNUT COLLECTIONS AGAINST STEM ROT DISEASE
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU, 2019-09-06) SACHIN HAWALADAR; Jahir Basha, C. R.
    Studies on diversity of Sclerotium rolfsii Sacc. and screening of groundnut collections against stem rot disease were carried out during 2018-19 at the Department of Plant Pathology, University of Agricultural Sciences, Bangalore. Survey was conducted in major groundnut growing districts of Karnataka to know the prevalence of groundnut stem rot disease. The disease is prevalent in the entire groundnut growing areas surveyed with maximum (18.65 %) and minimum (11.63 %) incidence recorded in Bagalkot and Dharwad district, respectively. Ten isolates of Sclerotium rolfsii were collected from different locations of Karnataka and its variability were studied. The morphological and cultural characters of these isolates varied with respect to their growth rate, time taken to initiate sclerotia, size and weight of sclerotial bodies. Guledagudda isolate (SrB2) produced largest sclerotial body (2.33 mm) and Madhugiri isolate (SrT2) proliferated much faster compared to other isolates (12 days). Variability of these isolates were analyzed by amplifying and sequencing the ITS rDNA region. Among the ten isolates, seven isolates viz., SrY1, SrY2, SrD1, SrD2, SrC1 and SrT1 shared more per cent identity with Athelia rolfsii, two (SrB2 and SrC2) share more identity with Sclerotium delphini and two (SrB1 and SrT2) share identity with both Athelia rolfsii and Sclerotium dolphini. The groundnut genotypes were screened against the stem rot disease to identify the resistance source. Among the 31 genotypes screened in disease sick plot, 15 genotypes were moderately resistant with disease incidence ranging from 10.10-30.00 per cent, 15 genotypes were susceptible and one genotype TMV-2, was highly susceptible.
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    ThesisItemOpen Access
    IDENTIFICATION AND CHARACTERIZATION OF POTENTIAL ENDOPHYTES AGAINST Sclerotium rolfsii Sacc. A STEM ROT CAUSING PATHOGEN OF GROUNDNUT
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU, 2019-09-06) RAJANNA, H. HADIMANI; Jahir Basha, C. R.
    Endophytes are living microorganisms present inside the plant tissues imparting tolerance against abiotic and biotic stress, in turn getting food and livelihood from plants. Exploration for fungal and bacterial endophytes as potential biocontrol agents against Sclerotium rolfsii. infecting groundnut was made by conducting in-vitro studies. Fungal and bacterial endophytes isolated from three selected varieties of groundnut viz., ICGV- 91114, ICG-13902 and JL-24 at three different time intervals (30, 60 and 90 days after sowing). Total of 237 fungal and 310 bacterial endophytes were obtained from 324 processed tissue segments, and were morphologically categorized into 96 fungal and 86 bacterial Operational Taxonomic Units (OTU’s) by considering the colony colour, pattern and texture of the endophytes and evaluated against Sclerotium rolfsii. infecting groundnut by dual culture technique. Out of 96 fungal OTU’s, one OTU and out of 86 bacterial OTU’s twelve OTU’s showed more than 50 per cent inhibition. Bacterial endophytic OTU 8ns1 isolated from ICG-13902 showed highest per cent inhibition (83.28) of Sclerotium rolfsii. Molecular characterization of potential endophytes by amplifying ITS region (ITS1 and ITS4 primers) for fungus and 16s rRNA region for bacterial endophytes revealed that, fungal endophyte as Fusarium solani (4pr2) and the bacterial endophytes as Lysinibacillus sp (4nr1), Alcaligenes feacalis (4nr1), Alcaligenes sp (8ns1), Orchobacterium intermedium (8ns2), from 30-days old sample. Similarly, Burkholdera cepacia (8nl3), Orchrobacterium intermedium (4nl2), Orchrobacterium intermedium (17nr4), Paenibacillus sp (4nl3), from 60-days old sample and Orchrobacterium sp (4nl4), Bacillus subtilis (8nl1), Alcaligenes sp (8ns1), Bacillus subtilis (17nl2) from 90-days old sample.