Research
Cluster Analyses Based on Yield and Yield Components in Fenugreek (Trigonella foenum-graecum L.) Accessions
In Ethiopia, there are insufficient information on genetic diversity in the Ethiopian fenugreek germplasms and need to study associations among seed yield and yield related traits. The overall objective of this investigation was cluster analysis using divergence and ranging the traits which were the most contributors to variation by principal component analysis. It was undertaken on 36 geographically diverse Ethiopian germplasms of fenugreek. The germplasms were collected from different regions of the country. These germplasms were tested in a 6x6 simple lattice at South Nation and Nationality Peoples Region (NNPR), Gesha Woreda, Kefa Zone, Deka, Ethiopia in 2013 main cropping season. Distances square (D2) analysis showed that 36 fenugreek germplasms grouped into six clusters. The distances were significant difference which helps for maximum genetic segregation and genetic recombination for crosses as well as obtaining heterotic response in breeding program for improving yield and yield related traits. Clustering pattern of genotypes was not related to geographical differentiation.
Effect of Curing and Top Removal Time on Quality and Shelf life of Onions (Allium cepa L.)
Onion (Allium cepa L.) is an important vegetable crop for small and commercial growers in Ethiopia where it is produced for both the local and export markets. But loss can be as high as 66% during storage due to loss in bulb fresh mass and sprouting. A study was therefore, conducted with the objective of optimizing curing and topping time for maximum bulb and storage life of onion quality and maximum days of storage on Onion cv. Bombay Red, at Melkassa Agricultural Research Center, Ethiopia, from January to May 2012. Bulbs were cured under shade for 0, 5, 10 and 15 days, respectively. The tops removed immediately, or removed 5, 10 or 15 days after curing or not at all. The experiment was laid out as a RCBD factorial(4x5x7 curing, topping, storage time respectively) and each treatment combination replicated three times. Data were collected with 15 days interval up to 90 days after curing. Data collected included spouted and rotted bulb percentage, bulb total soluble solids (TSS), bulb dry matter, and bulb fresh mass total loss and bulb color.
Test Cross Performance and Combining Ability of Maize (zea mays l.) Inbred Lines at Bako, Western Ethiopia
Information on combining ability and heterotic grouping for newly developed inbred lines is of paramount importance to design future breeding strategies for the development of hybrid and synthetic varieties. The objectives of the present study were to examine combining ability and to determine heterotic groups of the inbred lines for grain yield and other desirable traits. Twenty five inbred lines were used for the formation of the experimental crosses using line x tester mating design. The resulting 50 F1 crosses plus two standard checks (BH540 and BH543) were evaluated at Bako, Western Ethiopia in 2012 main cropping season. The entries were arranged in alpha lattice design with three replications. Data on grain yield, other agronomic traits and disease reactions were recorded under field condition. The highest grain yield was recorded from L24 x T1 (CML312/CML442) (9.97 t ha-1). The analysis due to mean squares for crosses was highly significant for all traits except for plant aspect, ear per plant, and number of plants per plot, and thousand kernel weights indicating the existence of genetic variability for all traits. GCA of line was significant for grain yield, agronomic traits and disease severity index. The mean square due to SCA for line by tester combinations were also significant for grain yield, stalk lodging, root lodging, ear rot, husk cover, maturity date, 50% silking day, and Turcicum leaf blight. Significant GCA and SCA effects were indicative of the importance of both additive and non additive gene effects in the control of the traits. However, in all traits, the proportion of GCA sum of square was higher than SCA sum of squares indicating the preponderance of additive gene effects in the control of all traits. Based on the SCA of crosses, the two testers used in this study successfully classified nine out of 25 tested inbred lines into two heterotic groups, A and B: six inbred lines belong to heterotic group A, while the remaining three belong to h
