Ram BhajanBhim Jyoti2016-06-142016-06-142013-07http://krishikosh.egranth.ac.in/handle/1/67352Thesis-PhDDeterioration in seed quality during ageing is a natural phenomenon. This is caused by alterations in various physiological/ biochemical parameters such as seed germination, seedling length, seed vigour increased in seed leachate, decreased of seed viability and dehydrogenase activity. Changes in these parameters adversely affect seed yield and related characters. A series of laboratory and field experiments were, therefore, conducted in the Department of Genetics and Plant Breeding and at the NEB Crop Research Center, G.B. Pant University of Agri. & Tech. Pantnagar, Distt. U.S. Nagar (Uttarakhand) from Jan 2010 to March 2012 to elucidate the effect of ageing periods on physiological, biochemical parameters, and seed yield and related traits in rapeseed-mustard. The material consisted of three oilseed Brassicas- toria (Brassica rapa var toria), yellow sarson (B. rapa var yellow sarson) and mustard (B. juncea L) and four varieties each of these namely PT-303, PT-507, T-9, and Bhawani of toria; Ragini, B- 9, PPS-1, and NDYS-2 of yellow sarson; and Vardan, Varuna, Kranti and NDRE-4 of mustard stored for one, two, three and four years in cloth bags under ambient conditions. Results showed decline in all the three physiological parameters with increase in ageing period. Significant reduction in all physiological and biochemical parameters were observed in 3 and 4 years old seeds. Maximum decline in physiological parameters was found in yellow sarson than mustard and toria. At varietal level, significant differences were observed for all physiological parameters. Rapid decline in physiological parameters was observed in PT-303 variety of toria, Ragini of yellow sarson and Varuna of mustard whereas, Bhawani of toria, B-9 of yellow sarson and Kranti of mustard showed less reduction for all physiological traits than other three varieties. At biochemical level, significant differences were observed due to crops and their varieties during ageing. In general, as ageing period increased, viability and dehydrogenase activity decreased but seed leachate increased. Significantly high leakage of seed leachate was observed in yellow sarson than mustard and toria. Less pronounced effect of seed viability and dehydrogenase activity during ageing was found in toria than mustard and yellow sarson. Significantly higher leakage of seed leachate accompanied by more reduction in seed viability and dehydrogenase activity was found in PT-303 of toria, Ragini of yellow sarson, and Varuna of mustard than other three varieties. Less reduction in these traits was found in Bhawani in toria, B-9 in yellow sarson, and Kranti in mustard. SDS-PAGE showed non-significant alterations in protein profiling during ageing for crops as well as varieties. Seed ageing delayed flowering more in mustard followed by in toria and yellow sarson. Higher reduction in seed yield was observed in yellow sarson than mustard and toria. At varietal level higher reduction in seed yield was observed in PT-507 of toria, Ragini of yellow sarson, Varuna of mustard. Bhawani of toria, B-9 of yellow sarson and Kranti of mustard showed less reduction in seed yield than other three varieties. On the basis of physiological, biochemical parameters and yield related traits it was inferred that seed of toria and mustard could be stored for two years without reduction in germination % under ambient condition. Toria was good storer than other two crops. Yellow sarson lose viability and vigour after one year ageing, may be due to high oil content, thin transparent seed coat and high leakage of seed leachate. At varietal level, Bhawani in toria, B-9 in yellow sarson, and Kranti in mustard showed better storability than others studied. Irrespective of crops, brown and small seeded types were less sensitive to ageing than yellow and bold seeded varieties.enbiochemistry, plant physiology, seed quality, seed aging, oilseeds, vigour, dehydrogenase, seed germinationThesis