Cowpea [Vigna unguiculata (L.) Walp] is one of the important climate-resilient legume crops for food and nutrition security in sub-Saharan Africa. Ethiopia is believed to harbor high cowpea genetic diversity, but this has not yet been efficiently characterized and exploited in breeding. The objective of this study was to evaluate the extent and pattern of genetic diversity in 357 cowpea accestions comprising landraces (87%), breeding lines (11%) and released varieties (2%), using single nucleotide polymorphism markers. The overall gene diversity and heterozygosity were 0.28 and 0.12, respectively. The genetic diversity indices indicated substantial diversity in Ethiopian cowpea landraces. Analysis of molecular variance showed that most of the variation was within in the population (46%) and 44% between individuals, with only 10% of the variation being among populations. Model-based ancestry analysis, the phylogenetic tree, discriminant analysis of principal components and principal coordinate analysis classified the 357 genotypes into three well-differentiated genetic populations. Genotypes from the same region grouped into different clusters, while others from different regions fell into the same cluster. This indicates that differences in regions of origin may not be the main driver determining the genetic diversity in cowpea in Ethiopia. Therefore, differences in sources of origin, as currently distributed in Ethiopia, should not necessarily be used as indices of genetic diversity. Choice of parental lines should rather be based on a systematic assessment of genetic diversity in a specific population. The study also suggested 94 accesstions as core collection which retained 100% of the genetic diversity from the entire collection. This core set represents 26% of the entire collection pinpointing a wide distribution of the diversity within the ethiopian landraces. The outcome of this study provided new insights into the genetic diversity and population structure in Ethiopian cowpea genetic resources for designing effective collection and conservation strategies for efficient utilization in breeding.

The experiment was conducted at Melkassa center of the Ethiopian Institute of agricultural Research for two season to investigate the effect of different onion planting methods on growth parameters and canopy development of onion cultivars. The experiment consisted of three planting methods of onion, namely direct seeding to the field, transplanting of seedlings and planting sets, and three onion cultivars (Adama Red, Bombay Red and Nasik Red). The experimental design was split plot with three replications; cultivars were assigned to the main plot and planting methods to sub-plot. Data were collected at 55, 70, 85 and 100 days after planting. Leaf area index were significantly (P<0.05%) higher on sets and transplants at all dates of observation. The correlation analysis results show highly significant (P<0.001) association between plant height, leaf area, LAI and shoot fresh and dry weight, with correlation coefficient ranging between 0.89 and 0.99. This indicates that any one of these parameters can be used for yield estimator depending on the condition and the facilities available. Regression analysis of total yield on leaf area index showed stronger dependence at 85 days after planting than the other dates as observed by a higher value of coefficient of determination (R 2 = 0.80). This study indicated that planting method has significant effect on the growth and performance of onion cultivars.

Bruchids are a major storage pest of common bean. Genetic resistance is a suitable method to avoid grain losses during storage. The objective of the study was to introgress the arcelin-based resistance locus into selected advanced breeding line and to validate the molecular marker BRU_00261. A total of 208 progeny F 4 families were phenotyped using a randomized complete block design, with three replications. Highly significant differences (P < .001) among the entries, parents and offspring were recorded for almost all traits. There was no significant difference between the two parents in the number of eggs laid. The progenies were grouped as highly resistant (34.3%), resistant (11.9%), moderately resistant (21.4%) and susceptible (32.4%).The levels of broad sense heritability ranged from 68.5%-93.9% for all the traits. Eighty-three most resistant lines and the parental lines were genotyped with the marker BRU_00261 (snpPV0007). The marker segregation deviated significantly from the expected independent segregation towards a strong enrichment for the resistant marker in the selected families. This marker will be useful for selecting promising materials in early generations and phenotypic confirmation of positive lines in later generations.

Multi-location variety trials were conducted to evaluate snap bean genotypes for yield and quality in 2013 and 2014 at Melkassa and Debrezeit agricultural research centers and Wonji. The experiment was laid out in RCBD with three replications. Data on yield and yield contributing traits were collected and subjected to environment wise analysis of variance followed by pooled analysis. The pooled analysis of variance for marketable yield showed significant difference (p< 0.01); and ranged from 7.5 t ha -1 to 9.14 t ha -1. Total green pod yield was also significant (p < 0.05); and ranged from 9.72 t ha -1 to 11.73 t ha -1 for genotypes BC4.4 and Plati respectively. There was also significant difference (p< 0.01) among genotypes in days to 50% flowering, pod diameter and length. Genotype Plati had the largest pod diameter (7.02 mm) and length(119.3 mm). The rest pod characters such as pod shape, color, fiber content and curvature were also diverse among genotypes. On the basis of total yield (11.73 t ha -1 ) and pod characters such as pod diameter(7.02 mm) and length(119.3 mm), low fiber content, green pod color, smooth pod surface, straight pod curvature and round pod shape, genotype Plati was identified as potential variety and thus released for production in the Central Rift Valley and similar agroecologies of Ethiopia.