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ThesisItem Open Access Ecofriendly management of Rhizoctonia solani causing black scurf of potato(CCSHAU, 2018) Manoj Kumar; Anil KumarIn recent years, among different fungal diseases of potato, black scurf disease has emerged as a serious problem caused by Rhizoctonia solani in most of the potato growing areas of India with 2-70 per cent disease incidence leading to considerable yield losses up to 50 per cent. Due to difficulties in disease management and lack of stable genetic resistance in potato cultivars against R. solani, different ecofriendly management aspects including fungicides, bioagents, organic amendments and cultural practices as well as systemic acquired resistance (SAR) activators in vitro and in vivo conditions were undertaken for effective management of the disease in present investigation. The in vitro and in vivo management study involving fungicides, bioagents or organic amendments indicated that among fungicides, Monceren, MEMC were most effective, whereas, in bioagents Trichoderma harzianum produced better results followed by T. viride. Among the organic amendments, vermicompost was found most effective followed by neem cake against black scurf of potato. Besides chemicals and biological control, cultural practices have also been used to minimize the inoculums level from the soil and tubers. Black scurf incidence is significantly influenced by irrigation level and depth of planting. As the irrigation frequency and depth of planting were increased, disease incidence and severity of potato black scurf was also increased. The delayed date of planting also affects disease incidence and severity. It was observed that soil moisture content is directly proportional to increased irrigation frequency and depth of planting. Black scurf disease incidence and severity showed a linear and negative correlation with soil temperature, whereas, a linear and positive correlation with soil moisture. Biochemical analysis indicated roles of systemic acquired resistance (SAR) inducing chemicals viz., salicylic acid, jasmonic acid, β-aminobutyric acid, γ-aminobutyric acid and hydrogen peroxide against black scurf of potato caused by R. solani. SAR activators play an important role in biochemical composition viz., total phenol, peroxidase, polyphenol oxidase and phenylalanine ammonia lyase and enhanced defense mechanism in potato crop for black scurf. It was also inferred from the study that all the biochemical constituents initially increased up to peak concentration after that, it decreased. Tubers dipping of SAR activators were found more effective to control the disease by reducing disease incidence as compared to foliar spray.ThesisItem Open Access Quantitative and qualitative losses due to Tyrophagus putrescentiae Schrank (Acari: Acaridae) in pearl millet and its management(CCSHAU, 2017) Manoj Kumar; Gulati, RachnaMonthly observations on the average population of T. putrescentiae in pearl millet grains revealed that mite number increased significantly at each observation period. The population was 73.33, 313.33, 680.67, 1065.67, 1316.00 and 1720.33 mites/5g grain after 30, 60, 90, 120, 150 and 180 days with the initial infestation density of 10 pairs of mites. On pearl millet flour, the population of T. putrescentiae was 439.00, 968.33, 1707.33, 2121.00 2366.00 and 3487.33 mites/ 5g flour after 30, 60, 90, 120, 150 and 180 days, respectively which differed significantly with each other from pre count of 10 mite pairs. Pearl millet flour was found significantly better in harbouring T. putrescentiae population as more number of mites (1587.00 mites/ 5g flour) was recorded than on pearl millet grains (741.33 mites/ 5g grain). Irrespective of the form of pearl millet, maximum number of mites (2603.83 mites/ 5 g pearl millet) was witnessed at 180 days which showed significant difference with mite numbers at other observation periods. Between the two forms of pearl millet, per cent weight loss was significantly more (10.50%) on pearl millet flour, as compared to pearl millet grain (6.00%). A significant negative correlation between the mite population and grain weight (r = - 0.99), flour weight (r = - 0.98) was obtained. Qualitative estimation of infested grains and flour revealed the decrease in total soluble sugars (19.72, 18.99mg/g), non reducing sugars (12.14, 10.01mg/g) starch (554, 454.13 mg/g) and protein (119.10, 114.77 mg/g) after 180 days of infestation, respectively as compared to 20.91, 13.90, 602.23 and 128.63mg/g at 0 day; depicting significant negative correlation. However, the reducing sugars exhibited a significant increase from 7.01 to 7.58, 7.65mg/g at 180 days of mite exposure in pearl millet grains and flour, respectively when subjected to initial count of 10 mite pairs, showing significant positive correlation. Percent loss in pearl millet germination due to T. putrescentiae population at different durations was recorded as 4.00, 20, 69.22, 98.67 and 99.33 per cent after 0, 30, 60, 90 and 180 days. All concentrations (0.2, 0.4, 0.6 and 0.8%) of aqueous extracts of lemon and orange peels in pearl millet grains caused 100 percent mortality in T. putrescentiae 20 and 28 days post treatment, respectively. In Aonla fruits extract treated grain, 13.20 mites were recorded from 8 percent concentration as compared to 20.11 mites in 0.8 percent.ThesisItem Open Access Inheritance And Association Studies For Yield, Its Components And Quality Traits In Tomato ( Lycopersicon Esculentum Mill(Chaudhary Charan Singh Haryana Agricultural University; Hisar, 2006) Manoj Kumar; Malik, Y. S.ThesisItem Open Access Effect Of Nutrients, Pinching And Growth Retardants On Growth, Flowering And Yield Of African Marigold (Tagetes Erecta L.)(Chaudhary Charan Singh Haryana Agricultural University; Hisar, 2006) Manoj Kumar; Joon, M. S.ThesisItem Open Access Study Of Relative Efficiency Of Sampling Strategies Under Super Population Models(Chaudhary Charan Singh Haryana Agricultural University;Hisar, 2002) Manoj Kumar; Goyal, K. C.ThesisItem Open Access Critical Analysis of Problems and Prospects of Groundnut Cultivation in Sub-Humid Southern Plain and Aravalli Hills (Zone IVa) of Rajasthan(Department of Extension Education, Rajasthan College of Agriculture: Udaipur, 2008) Manoj Kumar; Sharma, F. L.