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ThesisItem Open Access Ecofriendly Management of Fungal Foliar Diseases of Groundnut (Arachis hypogaea L.)(University of Agricultural Sciences, Dharwad, 2018-06) Aditya, Sanghmitra; Hegde, Gurudatt M.Groundnut is an important oilseed and food crop of India. An experiment was conducted in the Bioresource farm, IOF, UAS, Dharwad during kharif 2017 to know the relationship of weather factors with fungal foliar disease development and to manage them organically. The results from survey indicated that, the severity of early leaf spot (ELS), late leaf spot (LLS) and rust ranged from 20.00 to 42.22 PDI, 17.78 to 66.66 PDI and 17.78 to 60.88 PDI respectively. Maximum severity of fungal foliar diseases was recorded in Dharwad and minimum in Bagalkote district. Epidemiology studies revealed that early sowing on 22nd June 2018 escaped the rust infection while late sowing on 25th July 2018 escaped leaf spot infection. Spore load was highest during 38th standard meteorological week (SMW) for ELS and 40th SMW for LLS and rust. The correlation studies of PDI with weather parameters indicated a significant positive correlation with cumulative rainfall (CRF) and cumulative number of rainy days (CRD), irrespective of the dates of sowing. Regression studies indicated that fungal foliar disease development was significantly positively affected by CRD. In vitro spore germination studies revealed that all the botanicals evaluated (Adhatoda vasica, Azadirachta indica, Pongamia pinnata) were more effective at five per cent concentration against fungal foliar diseases. In vivo studies revealed that, minimum disease severity was recorded in consortia of bioagents (Trichoderma harzianum – Pseudomonas fluorescens – Bacillus subtilis) treated plots which was on par with wettable sulphur. All the plant growth and yield parameters were positively influenced in all the treatments when compared to the untreated control. The highest yield (41.51 q/ha), highest net returns (Rs. 1,21,712) and B:C ratio (3.75) was recorded in the consortia of bioagents treated plots.ThesisItem Open Access Synthesis, Characterization and Evaluation of Green Sulphur and Silver Nanoparticles Against Foliar Fungal Pathogens of Greengram(University of Agricultural Sciences, Dharwad, 2018-06) Srikanth H.N.; Nargund, V.B.In this study, synthesis of sulphur nanoparticles (SNPs) and silver nanoparticles (AgNPs) were attempted using pomegranate peel, aril and periwinkle leaf extract at the College of Agriculture, University of Agricultural Sciences, Dharwad. Reduction process in SNPs synthesis was assisted by addition of citric acid with sodium thiosulphate. Reduction process in AgNPs was done from AgNO3 by exposure to microwaves at 800 W for 90 sec. Change in the colour from colourless to dull white precipitate in SNPs and colourless to dark brown in AgNPs indicted the formation of nanoparticles. SNPs showed mean diameter of 61.1 - 83.4 nm in Particle Size Analyser (PSA) and shape was confirmed as spherical to irregular by Atomic Force Microscope (AFM) and Scanning Electron Microscope (SEM). AgNPs showed absorbance peak of 420 - 435 nm by UV-visible spectrophotometer, with mean diameter ranging from 46.8 - 81.8 by PSA and spherical in shape was confirmed by AFM and SEM. Characterised SNPs and AgNPs did not inhibit mycelial growth of Colletotrichum truncatum in food poison technique. However, they influenced the sporulation of C. truncatum. AgNPs at 3 ppm completely inhibited the germination of conidia of C. truncatum. Pomegranate aril based SNPs at 1000 ppm recorded the least PDI (7.15) which is on par with wettable sulphur @ 3000 ppm (6.48) and hexaconazole (8.52). AgNPs at 50 ppm completely inhibited the development of Cercospora leaf spot and anthracnose in glasshouse experiment. SNPs showed phytotoxicity at 5000 ppm and AgNPs at 500 ppm. Further sodium thiosulphate and AgNO3 showed phytotoxicity at 1500 and 169 ppm respectively. Pomegranate aril based SNPs against powdery mildew and pomegranate peel based AgNPs against Cercospora leaf spot and anthracnose, were effective in management at 1,000 and 50 ppm respectively under glasshouse condition.ThesisItem Open Access Loss Assessment and Integrated Management of Leaf Blight of Sweet Sorghum Caused by Exserohilum turcicum (Pass.) Leonard and Suggs.(University of Agricultural Sciences, Dharwad, 2018-06) Kiran B.M.; Patil, P.V.Field experiment on loss assessment was conducted at the Main Agricultural Research Station, UAS, Dharwad, during kharif 2017 in randomized complete block design with three replications and seven treatments involving the different number of sprays with hexaconazole (0.1 %) at weekly intervals. The results revealed, loss in the fodder yield to the extent of 37.20 per cent and reduction in sucrose content (21.17 %), crude fibre content (9.64 %), leaf ash content (62.91 %) and crude protein (13.00 %) was observed at the PDI of 67.40. Epidemiological study indicated significantly positive correlation with morning and evening relative humidity, rainfall and number of rainy days without any association with maximum and minimum temperature. Grain sorghum, bajra, foxtail millet and Johnson grass expressed the symptoms of leaf blight under artificial inoculation with E. turcicum. However, grain sorghum and Johnson grass showed the symptoms under natural conditions also. In vitro studies revealed, hexaconazole 5 EC at 0.1 per cent (100%), multineemore at 0.5 per cent (67.50 %) recorded maximum inhibition of mycelial growth and consortium of three bioagents, Trichoderma harzianum + Pseudomonas fluorescens + Bacillus subtilis at 3.3 g each/l and panchagavya at 5 per cent inhibited 80.44 and 19.50 per cent spore germination, respectively. In integrated management spray schedule under filed condition, hexaconazole at 0.1 per cent - hexaconazole at 0.1 per cent - hexaconazole at 0.1 per cent effectively reduced the severity of leaf blight (PDI-26.54, AUDPC-542.29) and increased the fodder yield (40.35 t ha-1) and sucrose content (12.42 %) with highest BC ratio (1:1.42) followed by hexaconazole at 0.1 per cent - multinemor at 0.5 per cent - hexaconazole at 0.1 per cent, which has recorded the PDI and AUDPC of 29.51 and 626.84, respectively with fodder yield and brix value of 37.96 t ha-1 and 11.15 per cent, respectively.ThesisItem Open Access Studies on Leaf Blight of Turmeric Caused by Alternaria alternata (Fr.) Keissler(University of Agricultural Science, Dharwad, 2017-09) Savar, Izazahammad; Virupaksha Prabhu H.ThesisItem Open Access Studies on Yellow Mosaic Disease of Soybean [Glycine max (L.) Merrill](University of Agricultural Science, Dharwad, 2017-09) Gaddeppa; Ashtaputre, S.A.ThesisItem Open Access Epidemiology and Management of Foliar Fungal Diseases of Greengram (Vigna radiata (L.) Wilczek)(University of Agricultural Sciences, Dharwad, 2017-07) Hulikatti, Vidya; Benagi, V.I.ThesisItem Open Access Studies on Bacterial Blight of Sesame Caused by Xanthomonas campestris pv. sesami Sabet and Dowson(University of Agricultural Science, Dharwad, 2017-09) Praveenkumar; Palakshappa, M.G.ThesisItem Open Access Studies on Collar Rot of Brinjal Caused by Sclerotium rolfsii Sacc.(University of Agricultural Science, Dharwad, 2016-12) Wahid, S A.; Kamanna, B.C.Brinjal (Solanum melongena L.) is one of the important vegetable crop. Collar rot of brinjal caused by Sclerotium rolfsii Sacc. is serious soil borne disease. A study on this was undertaken at the University of Agricultural Sciences, Dharwad during kharif 2015-16. Survey revealed that disease incidence ranged from 2.33 to 24.25 per cent. Highest mean disease incidence (9.75 %) was recorded in black soil. Dhruva hybrid showed high mean disease incidence of 11.52 per cent. . Significantly highest per cent disease incidence of 59.75 was recorded in plants of 15 days old in pot culture studies to know susceptible stage of brinjal. None of the genotypes were found resistant to collar rot pathogen. Among the six systemic fungicides tested under in vitro difenconazole, tebuconazole, hexaconazole and propiconazole at 0.1 per cent and 0.15 per cent concentrations inhibited cent per cent growth of S. rolfsii. Among the five contact fungicides mancozeb at 0.3 % concentration recorded maximum inhibition (60.25 %) of S. rolfsii followed by captan at 0.3 per cent concentration (55.19 %). Combi-products fungicides viz., thiram 37.5 % + carboxin 37.5 % WP and hexaconazole 4 % + zineb 68 % WP at 0.1, 0.2 and 0.3 per cent concentrations inhibited cent per cent o growth of S. rolfsii. Among six bioagents Trichoderma harzianum recorded maximum inhibition. Among thirteen botanicals, parthenium leaf extract recorded maximum inhibition (64.57 %). Among the different treatment combinations tested under pot conditions the combination of seedling dip with thiram 37.5 % + carboxin 37.5 % WP @ 2 g/l + application of FYM @ 200 g/pot + soil application of Trichoderma harzianum @ 4 g/kg followed by soil drenching with thiram 37.5 % + carboxin 37.5 % WP @ 2 g/l on 0, 15, 30, and 45 days after transplanting recorded the least per cent disease incidence (12.04 %).ThesisItem Open Access Studies on Yellow Mosaic Disease on Mungbean [Vigna radiata (L.) Wilczek](University of Agricultural Science, Dharwad, 2017-07) Rekha A.S.; Patil, M.S.A study on Mungbean yellow mosaic virus (MYMV) disease involving survey of four districts (Belagavi, Dharwad, Haveri, Gadag) in kharif 2016 and summer 2017, molecular characterization, host range, seed transmission, screening of advanced breeding lines and disease management was carried out during 2016-2017. During kharif 2016, the highest incidence (16.12 %) was in Haveri and the least (11.7 %) was in Gadag. During summer 2017, highest incidence (22.54 %) was in Dharwad and the least (20.73 %) was in Belagavi. The coat protein gene of MYMV (642 bp) was amplified using specific primers. PCR amplification, sequencing and construction of phylogenetic tree showed that MYMV Dharwad isolate was 99 per cent homology with different isolates of Horsegram yellow mosaic virus (HYMV). Therefore, MYMV of Dharwad isolate is the close relative of HYMV. MYMV was transmitted to seven crop plants except bhendi namely soybean, pigeonpea, blackgram, horsegram, frenchbean, cowpea, fieldbean and three weed hosts viz., Ageratum conyzoides, Corchorus trilocularis and Sida acuta and these hosts acts as collateral hosts. Studies revealed that MYMV was present in MYMV infected seeds and detected seed borne nature. Twenty-one of 24 advanced genotypes screened against MYMV during summer 2016 showed resistant reaction. Among different modules tested for the management of Mungbean yellow mosaic disease, adoptive module (M3) including seed treatment with Rhizobium (5 g/kg), border crop of maize (3 lines), yellow sticky trap (20/ha), Verticillium lecani (5 g/l), Triazophos (1.5 ml/l) at 30 DAS and spray of neem oil (5 ml/l) at 45 DAS recorded least disease incidence (8.94 %) and lowest whitefly population (2.20 whiteflies) with highest yield of 11.61 q/ha with B: C ratio of 3.00. Hence, adoptive module is best for management of yellow mosaic disease.
