http://ir.bdu.edu.et/handle/123456789/13994 Sat, 13 Jan 2001 06:33:22 GMT 2001-01-13T06:33:22Z http://ir.bdu.edu.et/handle/123456789/16731 Genetic Variability and Association Traits among Upland Rice (Oryza Sativa L.) Genotypes in Benishangul Gumuz, North Western Ethiopia Desalew Wondiferaw Rice (Oryza sativa L.) is one of the most important staple crops in the world, serving as a primary source of food for over half of the global population, though it has relatively short history of production and research in Ethiopia. Hence, genetic improvement is of paramount importance to increase the production and productivity of the crop, which requires understanding of genetic variability in the crop. The study was conducted during 2023/2024 main cropping season at Pawe Agricultural Research Center, Ethiopia, to determine the magnitude of genetic variability and interrelationships of yield and yield related traits in 80 upland rice genotypes.in an alpha lattice design with two replications, focusing on genetic analysis of variance showed significant differences among genotypes for 12 traits such as DH, DM, PH , PL, NPT ,NFGPP, BM, HI, TSW, SW and GSP .The highest genotypic variation (12.85) and phenotypic variation (20.51) was recorded for the number of productive, tiller per plant while the lowest GCV (0.96) and PCV (1.44) was recorded for days to maturity. Broad sense heritability value ranged from 80.18% for plant height to 29.51% for seed width. High genetic advance as a percent of the mean was observed for the number of productive tillers, plant height, grain yield, and thousand seed weight, indicating the presence of additive genes, making selection based on these traits successful. The highest positive correlations with grain yield were found for harvest index, biomass, and number of fill grains per panicle at both genotypic and phenotypic levels (r = 0.829, r = 0.541, r = 0.439). These indicated that improving upland rice through selection would be effective considering these traits. Path coefficient analysis revealed the maximum positive direct effect of harvest index and biomass yield on grain yield, indicating that considering these traits during the selection of rice genotypes would be more rewarding in evolving potential varieties of upland rice. The first five principal components with Eigen values greater than one accounted for 77.23% of the total variation among genotypes. Cluster analysis showed that genotypes were grouped into five clusters with the maximum inter-cluster distance between clusters IV and II (D2 = 2813.08), while the minimum inter-cluster distance was between clusters II and V (D2 = 574.91). Six rice genotypes with grain yield above 57.5 - 61.9 qt/ha-1 have been identified and based on the data for future breeding program that employ hybridization, parental material selection should be carried out between clusters rather than within clusters Fri, 01 Nov 2024 00:00:00 GMT http://ir.bdu.edu.et/handle/123456789/16731 2024-11-01T00:00:00Z http://ir.bdu.edu.et/handle/123456789/16730 Genetic Variability and Association of Yield and Yield Related Traits of Tef *Eragrostis Tef (Zucc.) Trotter+ Accessions at Alem Ketema Research Sub-Center, Centeral Ethiopia Tesfaye Sisay Tef is the most important staple cereal crop and is widely grown in Ethiopia, recognized as the center of origin and diversity in the country. Knowledge on genetic variability and trait associations is a key step in tef breeding programs. This study was conducted to evaluate the genetic variability, traits association, direct and indirect effect of yield related traits on grain yield of tef accessions. A total of 63 tef accessions collected from different parts of Ethiopia and one improved variety (Quncho, DZ-Cr-387) were evaluated for three qualitative and eighteen quantitative traits in 8x8 simple lattice design at Alem Ketema research sub-center during the 2023 main cropping season. The qualitative traits result showed that tef accessions collected from 2001-2500 m.a.s.l. had maximum H’ (0.86), whereas the lowest H’ (0.38) was obtained below 1500 m.a.s.l. The analysis of variance revealed significant differences among the tested accessions for all traits except thousand seed weight, indicating the existence of variability and potential for selection of the accessions for desirable traits. High GCV and PCV were observed for number of total tillers per plant, number of fertile tillers per plant, number of spikelets per panicle and flag leaf area. High heritability and high genetic advance as a percentage of mean were observed for days to heading (98.01%, 32.7%), days to physiological maturity (92.36%, 25.97%), plant height (90.9%, 26.97), panicle length (85.32%, 29.65%), culm length (86.92%, 27.57%), peduncle length (71.01%, 20.73%), number of spikelets per panicle (88.4%, 69.05%), number of primary panicle branches per main shoot (82.11%, 34.3%), flag leaf area (72.86%, 40.75%) and harvest index (81.48%, 28.93%) respectively. A positive and highly significant correlation was observed in genotypic level of grain yield and peduncle length (r=0.43), number of total tillers per plant (r=0.41), number of fertile tillers per plant (r=0.41), above ground biomass (r=0.35) and harvest index (r=0.76). A positive and highly significant correlation was observed in phenotypic level of grain yield and peduncle length (r=0.26), above ground biomass (r=0.62) and harvest index vii (r=0.67). Days to physiological maturity, plant height, number of primary branches per main shoot, flag leaf length, flag leaf width, above ground biomass and harvest index had positive direct effect on grain yield at genotypic level. At phenotypic level, positive direct effect on grain yield was exerted by days to heading, grain filling period, flag leaf area, above ground biomass and harvest index. This suggested that above ground biomass, grain yield and harvest index are the most important traits in selection of tef improvement. Cluster analysis grouped the accessions into five clusters consisting of 1 up to 27 accessions. The highest inter-cluster distance was noted between clusters I and III (372.87), while the lowest was between clusters IV and V (67.92). Principal components analysis revealed that three principal components with eigenvalues greater than one accounted for 82.8% of the total genetic variation among the tested tef accessions. The present results showed that the presence of wide range of genetic variations among tef accessions with desirable traits. This variation among traits could be used to develop varieties through selection and hybridization for tef grain yield improvement. Mon, 01 Jul 2024 00:00:00 GMT http://ir.bdu.edu.et/handle/123456789/16730 2024-07-01T00:00:00Z http://ir.bdu.edu.et/handle/123456789/16729 Genetic Variability and Association of Traits in Common Bean (Phaseolus Vulgaris L.) Genotypes in Sekota, in North-Westrn Ethiopia Abebe Assefa Common bean (Phaseolus vulgaris L.) is one of the most important pulse crops in Ethiopia, contributing to income generation and food security. Information on the genetic variability and trait associations of common bean in the Sekota district of north Western Ethiopia is inadequate. This study was initiated with the objective to assess variability, heritability and trait association among 64 common bean genotypes for quantitative traits using 8x8 simple lattice design at Aybra main research site 2023 under rain fed conditions. Analysis of variance was performed using SAS software and the ANOVA revealed highly significant variations among genotypes for all the traits considered in the study. The yield ranged from 1633.1 to 3702.10 kg ha-1 with a mean of 2542.53 kg ha-1. There was a yield advantage of 24.56 to 55.89% over the checks. A moderate genotypic coefficient of variation coupled with high heritability and high genetic advance as a percentage of the mean was obtained for plant height, branches per plant, hundred seed weight, seed yield, and harvest index. Branches per plant, aboveground biomass and harvest index had significant positive correlations and direct effects on seed yield at the genotypic and phenotypic levels while days to maturity had a significant negative correlation and indirect effect with seed yield at the genotypic. The maximum inter cluster distance was found between clusters VII and 8 (D2 =351.39), followed by clusters V and VIII (D2 =331.23). The first five principal component axes accounted for 74.3% of the total variation, with eigenvalues greater than unity. The number of days to maturity, plant height, number of pods per plant, number seeds per pod, seed yield, and harvest index were the traits that contributed most of the variation in the first PCs. Generally, the presence of variability, and strong positive association of traits among the genotypes were observed in the traits under study. Therefore, selection based on agronomic performance and hybridization based on cluster distance could be possible for the improvement of common bean in the study area. Mon, 01 Jul 2024 00:00:00 GMT http://ir.bdu.edu.et/handle/123456789/16729 2024-07-01T00:00:00Z http://ir.bdu.edu.et/handle/123456789/16497 Genetic Variability and Association Yield and Yield Component Traits in Tef [Eragrostis Tef (Zucc.) Trotter] Genotypes in Moisture Deficit Area of North Wollo, Ethiopia Yordanos, Demsie Tef [Eragrostis tef (Zucc.) Trotter] is one of the cerial crops in both area coverage and production in Ethiopia; however, its productivity is still lower due to absence of adapted varieties. Hence, a study on genetic variability is mandatory to identify and develop adapted varieties. Forty-nine tef genotypes were evaluated in 2022 to quantify the genetic variability of traits, and determine the association among traits using a simple lattice design. The analysis of variance result revealed the mean square values due to genotypes were very highly significant (p ≤ 0.001) for grain filling period, plant height, main shoot panicle length, fertile tiller number, lodging index, above ground biomass yield and grain yield. The highest estimated phenotypic and genotypic coefficients were recorded for days to heading(60.5-122.59), grain filling period(63.44-133.54), days to maturity(31.85-92.54), plant height(133.27-209.96),, main shoot panicle length(41.33-76.08) and loading index(29.94-50.40). The highest heritability coupled with high genetic advance as a percentage of mean (GAM) was recorded for above ground biomass yield, plant height and grain yield, implying the possibility of improving through effective direct selection. In addition, grain yield is positively and significantly correlated with above ground biomass yield both at genotypic and phenotypic levels. Above ground biomass yield (rg=0.85 and rp=0.55) and harvest index (rg=0.84 and rp=0.59) showed highest magnitude in path coefficients analysis at both phenotypic and genotypic levels.The 49 tef genotypes were clustered into four groups with an inter cluster distance ranging from 23.31 to 50.74. The first three principal components (PCs) accounted for 73% of the total genetic variation. Mon, 01 Jan 2024 00:00:00 GMT http://ir.bdu.edu.et/handle/123456789/16497 2024-01-01T00:00:00Z