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2016 - 20202
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Subject: Genetics and Plant Breeding × Author: Bairwa, Anil Kumar × Type: Thesis ×
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    ThesisItemOpen Access
    Studies on seed longevity and genetic diversity in soybean [Glycine max L. (Merrill)] germplasm
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2020-02) Bairwa, Anil Kumar; Shukla, P.S.
    Soybean ranked first among all the oilseed crops grown in India. It is highly adapted in varied agroclimatic conditions of plain as well as hills of the country. Non availability of good quality seed longevity soybean for sowing is one of the major constrain in soybean cultivation. Loss of seed longevity results in destitution of plant stand which is important for appropriate production and expansion of the crop. Planned utilization of genetic diversity present in land races, cultivars and wild relatives for any of the economically important traits aims at pyramiding of genes for higher productivity, better quality, and resistance to biotic and abiotic stresses to ultimately develop high yielding varieties. The amount of variability present in breeding material plays an important role in the progress of improvement of crop plants through selection. Genetic diversity and heterotic pooling are important parameters in selecting diverse parents to obtain heterosis.The present investigation was carried out during kharif-2016 and 2017 in augmented block design at N.E. Borlaug Crop research Centre, G. B. Pant University of Agriculture and Technology, Pantnagar to screen soybean germplasm for seed longevity and genetic diversity along with study of various genetic parameters. Two hundred eighty diverse germplasm lines were tested in completely randomized design with three replications for seed longevity on the basis of standard germination, methanol stress and seed morphological test. The analysis of variance for different characters revealed highly significant differences among the treatments for all the characters studied indicating the presence of sufficient variability among the experimental material. The genotypes CAT 451, CAT 2858, CAT 703, G 288, PP 26, CAT 953 and CAT 984 exhibited good germination percentage at both standard germination and after methanol stress test. The genotype G 288 showed maximum mean germination % after 18 month of storage with methanol stress test hence had maximum storability period than other genotypes. The genotypes CAT 451, CAT 2858, CAT 703, G 288, PP 26, CAT 953 and CAT 984 can be utilized in soybean crop improvement programme as a donor for high seed longevity and seed yield. All the studied traits revealed the presence of additive gene effect as these were considered highly heritable as they revealed to be connected with high broad sense heritability. The analysis of genetic diversity was performed by using Hierarchical method of cluster analysis. In pooled analysis 10 clusters were obtained and out of them cluster VII had the highest number of genotypes i.e. 162. Highest intra-cluster distance was recorded for cluster IV while the inter-cluster distance was highest between clusters I and cluster III. Cluster I, III and X showed highest cluster mean for the maximum number of trait. Selection of parents for hybridization could be made from these clusters to get desirable recombinants in order to improve the yield of soybean. Accessions of cluster I, III, IV, V, VI, IX and X can be included in the breeding program as donor for improving yield and yield contributing traits. Seed yield per plant was observed higher for germplasm lines CAT 2239, CAT 883 and CAT 294, which also shows superiority over best check. The study of pooled analysis revealed that two viz. numbers of pods per plant and dry matter weight per plant had high direct effect as well as significant and positive correlation with seed yield per plant hence direct selection for these traits will be beneficial and result in yield improvement. During amplification of SSR markers different genotypes like CAT 275, CAT 451, CAT 993 A, PP26, CAT 703 and CAT 748 were found significantly associated with markers for good seed longevity.
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    ThesisItemOpen Access
    Genetic variability and divergence analysis in early generation sugarcane (Saccharum species complex) clones based on morphological characterization
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2016-06) Bairwa, Anil Kumar; Singh, S.P.
    The present investigation was carried out in augmented block design, with 93 clones [which included 6 check varieties viz., Co Pant-3220, Co Pant-97222, Co Pant-90223, Co Pant84212, Co Pant-5224, Co S-8436 and 87 early generation (C2) clones] during 2014-15 at the Sugarcane Breeding Experimental Block of Norman E Borlaug Crop Research Centre, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Distt. U. S. Nagar, Uttarakhand. Genetic variability and divergence analysis were studied for fourteen morphological as well as juice quality parameters. The observation were recorded based on morphological characters viz., germination percent, number of tillers, number of millable cane, cane height, cane diameter, single cane weight, average number of internodes per cane, average inter nodal length, and quality characters viz., juice brix percent, juice sucrose percent, juice purity percent, CCS percent, CCS yield and cane yield. Data was analyzed statistically for Analysis of variance, Mean performance of genotypes, Estimation of variability, heritability, genetic advance and Genetic Divergence. Analysis of variances was carried out for all the 14 morphological as well as juice quality parameters revealed significant differences among clones for the characters studied like NMC, cane weight, inter node length and cane yield. Analysis of variances also revealed that there were significant differences among checks varieties for the Number of millable canes, cane height, inter nodal length and cane yield. NMC exhibited highest GCV. High heritability coupled with high genetic advance as percent of means was observed for germination percent, NMC/ha, cane height and inter node length. This indicated greater role of additive genetic effect in control of these characters and suggested that selection for these characters will be effective. The 93 genotypes including 6 checks were grouped in 9 clusters based on hierarchical cluster analysis and Cluster IX had the highest number of genotypes (34) and Cluster I, V and VII each had 1 genotype. Among all the clusters, cluster I and VI showed highest cluster mean across the maximum number of traits. It was observed that the accessions from cluster I, II and VI were suitable for higher germination percent, tillers/ha, NMC/ha, cane diameter, Brix percent, juice sucrose percent, CCS percent, cane yield and CCS yield. These traits comprised of the yield contributing characters thus they can be included in the breeding programme for the enhancement of yield.