Browsing by Author "Ravikumar"
Now showing 1 - 4 of 4
Results Per Page
Sort Options
ThesisItem Open Access Evaluation of Advanced Breeding Lines for Mungbean Yellow Mosaic Virus (MYMV) Resistance in Mungbean [Vigna radiata (L.) Wilzeck](University of Agricultural Science, Dharwad, 2016-08) Ravikumar; Suma MogaliIn the present investigation, eighty nine advanced breeding lines were evaluated for Mungbean Yellow Mosaic Virus (MYMV) resistance during two successive seasons summer2014 and summer 2015, amongst which, twenty fouradvanced lines showed moderate resistance to MYMV. Further, twenty four lines were evaluated in two replications for MYMV resistance during summer season 2015 under protected and unprotected condition. Out of twenty four advanced breeding lines, seventeen were found to be moderate resistant, three moderate susceptible, two susceptible and only one wild relatives of mungbean Vigna trilobata were found to be immune to MYMV during summerseason 2015.The genetic variability was also studied. Among the twenty four advanced breeding lines yield per plant were significantly and positively associated with number of pods per plant and number of seeds per pod. These advanced breeding lines which are high-yielding and also possess moderate resistance to MYMV can be released as new variety after large-scale field testing. The study was also conducted to validate molecular markers that were previously reported to be linked to major locus/QTLs governing MYMV resistance. Thirty markers were used for marker-trait analysis.Among the thirty,ten markers (viz.,CEDG008, CEDG257, CEDG006, CEDG244, CEDG115, CEDG041, CEDG084, CEDG201, CEDG304 and CEDG191) showed parental polymorphism. But these markers did not show association with MYMV resistance in advanced breeding lines. The crosses between MYMV susceptible and MYMV resistant parents were carried to develop mapping population for MYMV resistance. All the F1 plants from the cross between DGGV2 × Vigna trilobata were validated with thirty markers. Only two markers (CEDG006 and CEDG088) showed parental polymorphism in F1s. Two markers were used for molecular confirmation of F1 derived from a cross between DGGV2 × Vigna trilobata.ThesisItem Open Access EVALUATION OF ORGANICS AND INDIGENOUS PRODUCTS FOR THE MANAGEMENT OF Helicouerpa armigera (Bubner) IN CHILLI(UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BANGALORE, 2004) Ravikumar; Basavana Goud, K"A field trail was carried out using chilli var. Byadagi Dyavanoor during kharif season of 2002-03 at Main Agricultural Research Station, University of Agricultural Sciences, Dharwad to evaluate the organic amendments and indigenous products for the management of H. armigera. Studies on the effect of organic amendments on H. armigera revealed that among the different organic amendments, soil application of neem cake @ 1 t/ha was very effective in recording lowest eggs (0.69), larval population (0.62) and lowest fruit damage (6.5%) being on par with vermicompost @ 2 t/ha. Next best treatments were neem cake @ 0.5 t/ha + 50 per cent RDF, vermicompost @ 1 t/ha + 50 per cent RDF and RDF, Neem cake @ 1 t/ha recorded highest green chilli yield of 83.47 q/ha being on par with RDF (79.00 q/ha) and RPP (89.33 q/ha). These were followed by vermicompost @ 2 t/ha + 50 per cent RDF (76.00 q/ha) and neem cake @ 0.5 t/ha + 50% RDF (72.00 q/ha). Highest B:C ratio of 3.88 was noticed in neem cake @ 1 t/ha from among the organic amendments evaluated. Studies on the effect of indigenous sprays on H. armigera in chilli revealed that from among the indigenous products NSKE 5 per cent recorded lowest mean egg (1.15/plant), larval population (1.01/plant) and per cent fruit damage in NSKE 5 per cent (7.57%). This was followed by garlic chilli kerosene extract 3 per cent, NSKE 5 per cent + cow urine 10 per cent and NSKE 5 per cent + garlic extract 10 per cent. The efficacy of NSKE 5 per cent (79.32 q/ha), NSKE 5 per cent + cow urine 10% (78.00 q/ha), garlic chilli kerosene extract 3 per cent (76.23 q/ha), NSKE 5 per cent + garlic extract 3 per cent (83.67 q/ha) remained same in recording higher yield of green chilli. All the organic amendments evaluated either alone or their half doses in combiantion with 50 per cent RDF were safe to coccinellids {Menochiilus sexmaculatus Fab and Coccinella septumpunctata Thumb.) and Chrysoperal carnea Steph. in chilli ecosystem. All the indigenous sprays included in the study were safe to coccinellids and C. carnea except garlic chilli kerosene extract 3 per cent."ThesisItem Open Access SEASONAL INCIDENCE. VARIETAL PREFERENCE AND MANAGEMENT OF BER FRUIT BORER AND FRUIT FLIES(UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, DHARWAD, 2004) Ravikumar; Nandhihalli, B S"Investigation on the Seasonal incidence, Varietal preference and management of ber fruit borer and fruit flies were carried out from 1997-98 at the Regional Agricultural Research Station, Bijapur. The incidence of fruit borer and fruit flies started in second week of August and first week of October respectively. The borer activity reached high from second week of November to the end of January. Whereas, high incidence of flies noticed from November to third week of January. Among the eight varieties of ber screened, Illaichi recorded lowest infestation and is considered as moderately resistant against fruit borer and fruit flies. Umran recorded highest infestation of fruit borer while Sanaur-2, Umran, kadaka and Sanaur-6 were moderately susceptible to fruit flies infestation. Umran recorded maximum of 5 fruit borer larvae per fruit while Sanaur-2 had recorded maximum of 10 larvae of fruit flies per fruit. Increase in the fruit size resulted in the increase of oviposition by both the pests. Maximum emergence of adults was observed when pupae were at a depth of 2 cm below soil and loss due to fruit borer and fruit flies together was found to vary from 70.81 to 71.28 with an average of 71.05 per cent. The maximum loss due to damage by borer was 42.92 and that by flies was 28.12 per cent. Monocrotophos 36 SL was found effective against fruit borer and the same with jaggery was effective against fruit flies and NSKE 5% was found effective among botanicals in reducing the pest infestation and for effective control of pests three sprays at 12,14 and 16^ week after 50 per cent flowering was more economical. The residues of the chemicals after the last spray were below the tolerance limit."OtherItem Open Access முயல் தீவனத்தில் காய்கறிகளின் இலைகளை அளிப்பதன் மூலம் உடல் வளர்ச்சியில் ஏற்படும் மாற்றம் பற்றிய ஆய்வுKathirvelan, C.; Ravikumar; Viswanathan, K.; Kumarasamy, P.; TANUVAS