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University of Agricultural Sciences, Dharwad

The University of Agricultural Sciences, Dharwad was established on October 1, 1986. The University has 5 Colleges, 27 Research Stations, 6 Agriculture Extension Education Centers, 6 Krishi Vigyan Kendras and ATIC. The University has its jurisdiction over 7 districts namely Bagalkot, Belgaum, Bijapur, Dharwad, Gadag, Haveri, and Uttar Kannada in northern Karnataka. Greater diversity exists in soil types, climate, topography cropping and farming situations. The jurisdiction includes dry-farming to heavy rainfall and irrigated area. Important crops of the region include sorghum, cotton, rice, pulses, chilli, sugarcane, groundnut, sunflower, wheat, safflower etc. The region is also known for many horticultural crops. Considerable progress has been registered in the field of education, research and extension from this University.

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Thesis Type: Ph.D × Subject: Plant Pathology ×
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Now showing 1 - 9 of 86
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    ThesisItemOpen Access
    Synthesis, Characterization and Evaluation of Coppera and Sulphur Nanoparticles Against Major Plant Pathogens
    (University of Agricultural Sciences, Dharwad, 2018-03) Swamy, Chikkanna; Nargund, V.B.
    Green nanotechnology is the current requirement in plant pathology and considering the magnitude of this novel technology, investigations were undertaken on green synthesis of copper nanoparticles (CuNPs) and sulphur nanoparticles (SNPs), characterization and evaluation against the major plant pathogens to mitigate the disease problem effectively both in vitro and in vivo condition at College of Agriculture, University of Agricultural Sciences, Dharwad. Green syntheses of NPs were attempted from seven plants by six methods in copper and two methods in sulphur. Particle Size Analyzer confirmed the average diameter of nanoparticles was < 100 nm [CuNPs (32.5 nm) and SNPs (56.00 nm)]. Circular to irregular in shape of NPs was confirmed by AFM and SEM. Recovery of CuNPs and SNPs was highest in pome granate pericarp mediated synthesis. Major five fungal and three bacterial plant pathogens were isolated by standard procedure and characterized by molecular techniques. CuNPs inhibited the cent per cent spore germination of Exserohilum turcicum at 500 ppm. SNPs showed cent per cent inhibition of spore germination of Golovinomyces cichoracearum at 10 ppm. Mango leaf based CuNPs inhibited the growth of Xanthomonas axonopodis pv. punicae (17.33 mm) and Ralstonia solanacearum (12.00 mm) at 2,000 ppm. In chickpea, SNPs at 1,000 ppm recorded highest seed quality parameters by paper towel method and was on par with carboxin (37.5 %) + thiram (37.5 %). Under glasshouse condition, SNPs at 500 and 1,000 ppm managed the greengram and cowpea powdery mildew diseases respectively. Citrus canker and bacterial wilt of tomato diseases were significantly managed by CuNPs over untreated control and remained on par with standard antibiotic check. Green synthesized CuNPs and SNPs were found effective in reducing the diseases caused by major fungal pathogens compared to bacteria at lower concentrations. No phytotoxic symptoms were observed on tomato seedlings at 2000 ppm.
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    ThesisItemOpen Access
    Studies on Soil Borne Fungal Diseases of Chickpea
    (University of Agricultural Science, Dharwad, 2015-11) Ravichandran S.; Hegde, Yashoda R.
    Chickpea (Cicer arietinum L.) is the most important Rabi pulse crop in India. Important soil borne fungal diseases observed during survey were wilt caused by Fusarium oxysporum f.sp. ciceri,(FOC) (27.07%), dry root rot caused by Rhizoctonia bataticola (RB) (37.06%) and collar rot caused by Sclerotium rolfsii (0.65%), alone and in combination (34.32%) with the disease incidence ranging from 1.4 to 23.4 per cent. In interaction studies, JG 11 and JAKI 9218 were moderately resistant to FOC, however were susceptible to RB and S. rolfsii. In cultural studies, FOC and RB attained maximum growth at 16 and 14 days respectively. Temperature of 25 – 300C and pH of 6 to 7 were optimum for growth of these two pathogens. 32 isolates of FOC were collected and classified into three groups based on growth rate virulence index and dry mycelial weight. 20 isolates of RB collected varied in growth and dry mycelial weight. In race identification of FOC by using differentials indicated that all isolates belong to race 1a and further confirmed by amplification with specific primer. ITS rDNA sequence analysis and specific primers confirmed the identity of isolates of FOC and RB. Twenty six genotypes showed resistant reaction against FOC in wilt sick plot in two years and five genotypes remained resistant even in glasshouse screening. All tested triazoles and comi product fungicides and eucalyptus leaf extract was effective in mycelial inhibition of both pathogens. Highest inhibition of FOC was observed in Trichoderma harzianum and RB was by Pseudomonas fluorescens. Seed treatment with carboxin + thiram recorded the lowest per cent disease incidence with the highest yield and cost benefit ratio in field experiment studies in Farmer’s field, (Bailhongal) and sick plot at Kalaburgi.
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    ThesisItemOpen Access
    Bacteriophages : Characterization and Utilization as Biocontrol Agents Against Xanthomonas Axonopodis pv. citri (Hasse) Vauterin et al. And Ralstonia solanacearum (Smith) Yabuuchi et al.
    (University of Agricultural Science, Dharwad, 2015-10) Manyam, Pradeep; Nargund, V. B.
    Citrus canker and solanaceous bacterial wilt are the most devastating diseases which leads to heavy economic losses. In present study, bacteriophages are used as biocontrol agents against Xanthomonas axonopodis pv. citri (Xac) and Ralstonia solanacearum. Five native cultures of Xac and R. solanacearum were isolated, confirmed for their pathogenicity and molecular identity. Three phages of Xac (Xacpv1, Xacpv2 (phylloplane) and Xacpv3 (rhizosphere)) and two phages of R. solanacearum (Rspv1 (pond water) and Rspv2 (rhizosphere)) were isolated. Host range studies revealed Xacpv1and Rspv1phages with broad lytic activity on their respective hosts. All the Xac and R.solanacearum phages were chloroform insensitive and non-specific to other tested bacteria. Xacpv3 and Rspv2 phages completed their entire life cycles in 70 and 90 min with average burst sizes of 25 and 85 Plaque Forming Units (PFU) per infected cell respectively. Phage morphology of Xacpv1 and Xacpv2 showed icosahedral heads with short tails (Podoviridae). Xacpv3 and Rspv1 showed an icosahedral heads with long contractile tails (Myoviridae) and Rspv2 appeared in long contractile fibers (Inoviridae). RAPD analysis with four random primers showed that all the Xac and R. solanacearum phages were diverse in nature. In phage stability studies, Xac phages on citrus phylloplane population rapidly came down after four days of application from 8 to 3 log PFU/ml. Significant difference between formulated and unformulated phages was observed after eight days of application. In rhizosphere of tomato seedlings, both formulated and unformulated phages of R. solanacearum retained high phage concentration for 16 days. In glasshouse studies, the per cent disease reduction of citrus canker over control was maximum (61.55%) in T3 (Copper oxy Chloride (0.3%) + Streptocycline (500 ppm)) followed by T4 (Phage mix) (58.59%). The seedling stages of both tomato and brinjal phages performed better than other individual components of IDM in reducing bacterial wilt.
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    ThesisItemOpen Access
    STUDIES ON ZONATE LEAF SPOT OF SORGHUM CAUSED BY Gloeocercospora sorghi D. Bain & Edg
    (University of Agricultural Sciences, Dharwad, 2001) PALAKSHAPPA, M G; HIREMATH, R V
    ABSTRACT NOT AVAILABLE
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    ThesisItemOpen Access
    BIOLOGICAL CONTROL OF CHARCOAL ROT OF SORGHUM [Sorghum bicolor (L .) Moench] CAUSED BY Macrophominaphaseolina (Tassi) Goid
    (University of Agricultural Sciences, Dharwad, 2000) DESAI, SUNIL A; KULKARNI, SRIKANT
    ABSTRACT NOT AVAILABLE
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    ThesisItemOpen Access
    DEVELOPMENT OF BIO-INTENSIVE INTEGRATED MANAGEMENT STRATEGIES AGAINST ROOT-KNOT NEMATODE Meloidogyne incognita (KOFOID AND WHITE) CHIT WOOD INFECTING TOMATO
    (University of Agricultural Sciences, Dharwad, 1999) RAMASWAMY, S D; PARVATHAREDDY, P
    ABSTRACT NOT AVAILABLE
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    ThesisItemOpen Access
    INTEGRATED MANAGEMENT OF PHYTOPHTHORA FOOT ROT OF BLACK PEPPER THROUGH VA MYCORRHIZA AND HOST PLANT RESISTANCE
    (University of Agricultural Sciences, Dharwad, 2000) Lokesh, M S; Anahosur, K H
    The black pepper vines of both cultivated and vines in the forest areas are invariably associated with the native isolates of VA mycorrhiza viz., Glomus fasciculatum and Acaulospora sp. The native isolates VA mycorrhiza were effective in combating the Phytophthora foot rot of black pepper alone and its effects is synergestic when integrated with either Trichoderma viride or potassium phosphonate (Akomin, @ 0.3 per cent). The cuttings of black pepper viz., Vokkalu , Mottakare, Thirupukare showed least incidence of disease when the cuttings were preinoculated with native isolates of VA mycorrhiza then challenged with Phytophthora capsici. Vokkalu type 1 and 2, Uddakare accession 1 and 2, Thimpukare, Balankotta - II, Neelamundi-ll, Narayakodi-IV and Kudargutta showed tolerance to P. capsici at lower inoculum potential i.e., 25 zoospores/vine. The explant initiated the callus in presence of 0.5 mg I-1 BA in combination with either 1.0 mg I-1 2,4-D or 2.0 mg I-1 NAA or IBA or lAA whereas, the callus could be easily maintained in half strength MS medium supplemented with 1.0 mg I-1 2,4-D. Callus of cultivars viz., Vokkalu type-1 and 2 are having slight tolerance at one per cent toxic metabolites of Phytophthora capsici The shoot tip explant of Uddakare and Thimpukare produced multiple shoots in half strength MS medium with 2.0 mg 1 BA and 0.01 mg I-1 NAA. NAA (1.0 mg 1-1) and IBA (1.0 mg I-1) were found effective in rooting of the shoot. Micro propagated plantlets of black pepper were hardened by planting in 1:1 sand and coir pith in humid chamber for 30 days.
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    ThesisItemOpen Access
    MANAGEMENT OF WILT AND ROOT ROTS OF COTTON WITH SPECIAL REFERENCE TO BIO FUNGICIDES
    (University of Agricultural Sciences, Dharwad, 2002) CHATTANNAVAR, S N; KULKARNI, SRIKANT
    Survey was revealed that wilt caused by Fusarium solani up to 20 per cent followed by Rhizoctonia solani and Rhizoctoina bataticola up to six percent and Sclerotium rolfsii was negligible. Among nine isolates of F. solani, the Raichur isolate was more virulent.Among twelve cultures of Trichoderma and two cultures of Gliocladium virens against all four pathogens. T. harzianum of Dharwad isolate was the best and G. virens of TNAU was the best. In growth period studies, T. harzianum reached its peak on 12th day and maltose and dextrose were best to support the growth. Transparent polythene bag was superior. Among substrates wheat bran was superior. In seed treatments, @ 8g/kg of seed and among soil applications, three percent was superior. In the combination, seed treatment @ 8g/ kg with 1% soil applicaiton was superior. Among agro chemicals tested for both T. harzianum and pathogens, the fungicides, carbendazim and benomyl were inhibitory to T. harzianum. Benomyl and carbendaizim were excellent to control F. solani. Similarly, benomyl, methoxy ethyl mercury chloride (MEMC), carboxin, thiram and MEMC were superior to control R. solani and R. bataticola respectively. For S. rolfsii, carboxin was the best. Among insecticides, chlorpyriphos was inhibitory to T. harzianum followed by imidachloprid. Endosulfan was least inhibitory. Carbofuran, phorate and endosulfan were less effective to pathogens. Among herbicides, alachlor was more deletorius than paraquat. Diuron was effective against all four pathogens. Among organic amendments neem cake was superior in suppressing the growth of all four pathogens. In storage studies, increase in temperature lowered cfu and at 0°C it was maximum and wheat bran was the best and can be stored upto five months. Culture filtrates of all twelve Trichoderma and two G. virens on seed germination of Jayadhar and Abhadita with delinted and fuzzed seeds revealed that delinted seeds had better germination and culture filtrates enhanced seed germination.
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    ThesisItemOpen Access
    STUDIES ON RACES, ECOLOGY, DETECTION AND CONTROL OF Xanthomonas campestris pv. vesicatoria (Doidge) Dye CAUSING BACTERIAL SPOT OF TOMATO (Lycopersicon esculentum Mill.)
    (University of Agricultural Sciences, Dharwad, 1997) RAVI KUMAR, M R; Nazir Ahmed Khan, A
    ABSTRACT NOT AVAILABLE