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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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1998 - 199912000 - 20011
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Subject: Plant Pathology × Author: AMARESH, Y. S. × Start date: 1961 × Type: Thesis ×
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    ThesisItemOpen Access
    STUDIES ON FOLIAR DISEASES OF SUNFLOWER (Helianthus annuus L.) WITH SPECIAL REFERENCE TO ALTERNARIA LEAF BLIGHT CAUSED BY Alternaria helianthi (Hansf.) Tubaki and Nishihara
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK BANGALORE, 1998-08-19) AMARESH, Y. S.; NARGUND, V.B.
    Among the several diseases affecting sunflower crop, foliar diseases contributed more loss in yield. These include Alternaria leaf blight caused by Alternaria helianthi (Hansf.) Tubaki and Nishihara and rust caused by Puccinia helianthi Schw. Survey on incidence of Alternaria leaf blight and rust revealed that Alternaria leaf blight was more severe in Kharif and rabi seasons, while rust was less severe during 1996-97. Survival oi A.helianthi in infected stalks was more than 360 days in the laboratory conditions, while under natural conditions its survival was upto 240 days. The safflower was found to be collateral host for A. helianthi. The culture filtrate of A. helianthi showed the wilting symptoms within 24 hr. on tomato and sunflower seedlings and also inhibited the germination of both sunflower and sorghum seeds. Further, the culture filtrate inhibited root and shoot elongation of sunflower and sorghum. Toxin was partially purified. It was host specific and thermostable, produced typical symptoms on sunflower leaves without yellow halo. Among the 110 sunflower genotypes screened only three genotypes viz HPM-15R HPM-116 and HPM-140 were found resistant to both Alternaria leaf blight and rust. In case of m vitro evaluation of fungitoxicants mancozeb (0.3%), cyproconazole (0.1 %) were most effective in inhibiting mycelial growth and also per cent inhibition of spore germination of A. helianthi. Plant extracts were not effective. For rust tridemorph (1000 ppm) and cyproconazole (1000 ppm) were most effective in inhibiting uredospore germination of P.helianthi. In field evaluation of fungicides and plant extracts, chlorothalonil (0.2%), cyproconazole (0.1%) and mancozeb (0.2%) gave the best control of Alternaria leaf blight and rust resulting into increased seed and oil yield.
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    ThesisItemOpen Access
    EPIDEMIOLOGY AND MANAGEMENT OF ALTERNARIA LEAF BLIGHT AND RUST OF SUNFLOWER (Helianthus annuus L.)
    (UNIVERSITY OF AGRICULTURAL SCIENCES GKVK BANGALORE, 2001-08-04) AMARESH, Y. S.; NARGUND, V. B.
    Alternaria leaf blight caused by Altemaria helianthi and rust caused by Puccinia helianthi are two major foliar diseases of sunflower. The yield loss due to Alternaria leaf blight and rust was estimated to be 43.90 and 32.65 per cent during 1998-99 and 1999-2000 respectively. AUDPC value was found to be a better parameter for yield loss assessment and epidemiological model was developed. Autoregressive method of seventh order was used for estimating both uredospore and condial load interms of previous successive seven days. The disease development was predicted by first order autoregressive model and logistic model. The toxin produced by A.helianthi was purified and identified as 3 propyl 4 hydroj^ -2oxy -2-3 dihydro furone. The toxin produced typical brown necrotic spots without yellow halo on susceptible sunflower cv. Morden. PAC-36, PAC-304 and DSH-34 were identified as slow blighters and PAC-36, PAC-304 GK-2002 and GAUSUF-15 as slow rusters. Sugars and phenols were more in diseased leaves than healthy leaves. The isozyme studies on catalase, peroxidase and polyphenol oxidase revealed their role in disease development. The higher incidence of Alternaria leaf blight and rust was noticed in kharif and rabi sown crop respectively. Among 30 plants screened, Allium sativum, A.cepa, Amamthus viridis, Ocimum sanctum, Tridax procumbens, and Melia azedarach were found effective against both pathogens. Chlorothalonil, mancozeb, propiconazole and hexaconazole were most effective against both the pathogens. Pseudomonas fluorescens was found to be a better bioagent in the management of both diseases. Among 140 sunflower genotype AGO.No.405, 1583, PAC-36 and PAC-336 were found resistant to both Alternaria leaf blight and rust. In integrated disease management of Alternaria leaf blight the treatment fungicide followed by Pongamia and P. fluorescenss was found to be effective in reducing the disease.