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2000 - 200944
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Subject: Plant Pathology × End date: 2009 × Start date: 2000 × Thesis Type: Ph.D ×
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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
    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
    EPIDEMIOLOGY AND MANAGEMENT OF ALTERNARIA LEAF BLIGHT AND RUST OF SUNFLOWER (Helianthus annuus L.)
    (University of Agricultural Science, Dharwad, 2000) Amaresh, Y S; Nargund, V B
    "Alternaria leaf blight caused by Alternaria 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 hydroxy -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 ACC.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."
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    ThesisItemOpen Access
    STUDIES ON VIRAL DISEASES OF POTATO WITH REFERENCE TO EPIDEMIOLOGY AND MANAGEMENT
    (University of Agricultural Science, Dharwad, 2000) Devaraju; Patil, M S
    "Potato is one of the most important commecial vegitable crops cultivated in Kamataka Among the viral diseases mosaics and leaf roll are most common. The survey was conducted during kharif 1999 and summer 2000, the incidence of viral diseases was ranged from 4.20 to 66.75 per cent. Incidence of severe mosaic ranged from trace to 36.00 per cent and leaf roll incidence ranged from 4.20 to 40.75 per cent in both Hassan and Kolar districts, whereas mild mosaic incidence was not noticed in both the districts The. mild mosaic virus (PVX) was sap transmissible to different indicator plants and produced systemic symptoms on tobacco, Micotiana glutinosa, tomato and Capsicum annuum and local lesions on cowpea, beans, Gomphrena glohosa and Chenopodtum amaranticolor. Severe mosaic virus (PVY) produced systemic symptoms on tobacco, Nicotiana tabacum var. white burley and samsun, Nicotiana glutinosa, Datura metel, Nicandra physaloids. Petunia hyhrida and Capsicum annuum and local lesions on Chenopodium amaranticolor. The mild mosaic, severe mosaic and leaf roll viruses were transmitted through seed tubers. Aphids {Myzus persicae) transmitted severe mosaic and leaf roll viruses in a non-persistent and persistent manner, respectively. The mosaics had slight effect on yield and yield parameters, whereas the leaf roll infection at early stages resulted in greater yield loss than later stages infection. The lower disease incidence and the higher tuber yield was obtained in early planted crop (June 1st to June 21st) than late planted crop, therefore the spread of diseases could be minimised by adopting early planting Mulching with polyethylene sheet and aluminium foil immediately after emergence resulted in reduction of severe mosaic and leaf roll diseases incidence. In tissue culture studies, maximum number of PVY free potato plantlets were obtained by meristem-tips obtained from seedlings of true potato seeds (94.44) than that of severe mosaic (PVY) infected plants (69.44%)."
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    ThesisItemOpen Access
    EPIDEMIOLOGY AND MANAGEMENT OF LEAF BLIGHT OF WHEAT CAUSED BY Exserohilum hawaliensis (BUGNICOURT) SUBRAM. AND JAIN, Ex. M. B. ELLIS
    (University of Agricultural Science, Dharwad, 2000) Patil, Vasant Shamrao; Kulkarni, Srikanth
    "The leaf blight of wheat caused by Exserohilum hawaiiensis is one of important diseases of wheat. The survey revealed maximum disease incidence in Raibag, Gokak, Athani and Dharwad taluks in Kamataka and Mahabaleshwar, Pane, Karad, Niphad taluks in Maharashtra. The loss assessment study indicated reduction in thousand grain weight (18.12%), grain yield (31.30%), height of plants (7.05%) and biomass (19.17%). Crop loss model using input variable PDI was of the farm y = -32.33+1.16 (PDI). The pathogen stirvived only for few weeks in soil, as it was highly aerobic. The pathogen survived under laboratory conditions for 21 months, 15 months under natural conditions, 27 months under refrigerated conditions and remained viable in seed for 28 months. The pathogen could infect Chloris barbata, Dectyloctenium aegypticum, Eleusine coracana, Oryia saliva, Sorghum bicolor and Zea mays. The perfect state of the pathogen could not be detected. The spore load of E. hawaiiensis showed fluctuations over time from 2.38 to 8.08 per microscopic field per day. Eight isolates obtained from field of different localities. The variability among hyphal tip isolates was assessed on the basis of morphological, cultural, physiological, nutritional and pathogenicity characters. The isolates were classified into four groups such as Group-I: E, F, G, Group-11: B and C, Group-Ill: D and H, Group-IV: A based on their cultural characters. On the basis of pathogenicity, isolates were classified into three group as highly virulent (Mahabaleshwar and Ugar Khurd), Moderately virulent (Arabhavi, Dharwad and Sangankerij and least virulent (Kannur, Digraj and Pune). Seed treatment with captan or mancozeb or combination of either of them with Trichoderma viride recorded cent per cent control of primary seed borne inoculum. Among the fungicides, propiconazole was found effective. The plant extracts viz., Eucalyptus globus, Lantana camara, Flacourtia ramontchi, Acacia concina, Memecylon edule and Ma^nifera indica were found effective against E. hawaiiensis."
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    ThesisItemOpen Access
    HOST PREFERENCE OF Bemisia tabaci (Gennadius) AND MANAGEMENT OF TOMATO LEAF CURL VIRUS DISEASE
    (University of Agricultural Science, Dharwad, 2001) Ganesha Naik, R; Muniyappa, V
    ABSTRACT NOT AVAILABLE
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    ThesisItemOpen Access
    STUDIES ON BLIGHT DISEASE OF CHICKPEA CAUSED BY Colletotrichum dematium (Pers. ex Fr.) GROVE
    (University of Agricultural Science, Dharwad, 2000) VARAPRASADA RAO, C H; NARAYANA, Y D
    ABSTRACT NOT AVAILABLE