Chawla, H.S.Mall, Neetu2016-07-122016-07-122011-08http://krishikosh.egranth.ac.in/handle/1/68665Thesis-PhDThe present study was carried out on 24 maize and 11 French bean varieties with the objectives: i) To provide a detailed description of morphological DUS descriptors for maize and French bean varieties over two years as per the DUS guidelines; ii) To determine the relative extent of distinctiveness, uniformity and stability of morphological DUS descriptors; iii) Characterization of the varieties by biochemical and molecular markers to complement the morphological DUS descriptors. The field experiments for maize and French bean were conducted in the two kharif seasons and two Rabi seasons of 2008-2009 and 2009-2010 at Crop Research Centre and Vegetable Research Centre respectively. Data were recorded for 31 and 22 morpho-physiological DUS descriptors for maize and French bean respectively. Among 31 descriptors of maize, 19 were visually assessed, 4 neither visual nor measurable and 8 were measurable characteristics. 1 character was monomorphic, 12 were dimorphic and 5 were polymorphic for visual characters. All neither visual nor measurable characters were dimorphic. Out of 8 measurable characteristics 1 was monomorphic, 5 were dimorphic and 2 were polymorphic. Among 19 visual characters of French bean, 13 were dimorphic and six were polymorphic. All the 3 measurable characters were polymorphic indicating their potential for varietal characterization. No intra-varietal variation was observed for any of the visual characteristics except for one character in French bean and expression of characters in different varieties remained same for two consecutive years confirming the uniformity and stability of the varieties. COY-D analysis was made on 8 and 3 measurable DUS descriptors of maize and French bean respectively. COYD analysis supported with MJRA analysis revealed that the slope of the MJRA curve and regression probability were too negligible which indicated that all the considered characteristics were independent and their interactions with environment as well as with themselves were negligible in both the years respectively. This indicates the distinctiveness of all the candidate varieties. COY-U analysis revealed that all the varieties were more or less uniform for measurable characters. However, 2 varieties in maize and six varieties in French bean requires further purification for one more year. PCV and GCV showed greater magnitude of differences in maize which indicates less stability however in French bean high heritability indicated the presence of additive gene action in the expression of characters, emphasizing their consistency and stability over the years and their utility in varietal characterization. On the basis of grouping characteristics unique morphological profiles were obtained for 14 maize and 3 French bean varieties. When all the morphological descriptors were considered then all the varieties of maize were distinguished and seven varieties of French bean were discriminated. Seed storage protein profiling of varieties discriminated six varieties by SDS-PAGE in maize and four varieties in French bean. Molecular marker analysis was conducted with two markers viz. RAPD and SSR in maize and SSR in French bean. RAPD and SSR analysis with 10 primers each exhibited high level of polymorphism. Unique specific bands were obtained for fourteen varieties with RAPD marker and 8 varieties in maize with SSRs marker. When both the molecular markers were considered, a total of 16 varieties could be discriminated in maize. SSRs in French bean with 10primers revealed very high degree of polymorphism. Distinctive profiles were obtained for four varieties. When biochemical and molecular markers were considered then overall nine varieties were discriminated out of 11 varieties in French bean. Thus, DUS descriptors were found reliable and reproducible for establishing the distinctiveness of the varieties but sometimes morphological DUS descriptor alone may not be sufficient for establishing the distinctiveness of varieties. However, when supplemented with different biochemical and molecular markers majority of the varieties could be delineated. The varieties satisfying the DUS criteria can be registered with PPV&FR authority for obtaining breeders and Farmer’s rights.encharacterization, maize, zea mays, phaseolus vulgaris, plant morphology, biochemistry, molecular markers, DUS, plant physiologyThesis