Sixteen faba bean genotypes were evaluated in 13 environments in Ethiopia during the main cropping season for three years (2009)(2010)(2011). The objectives of the study were to evaluate the yield stability of the genotypes and the relative importance of different stability parameters for improving selection in faba bean. The study was conducted using a randomized complete block design with four replications. G × E interaction and yield stability were estimated using 17 different stability parameters. Pooled analysis of variance for grain yield showed that the main effects of both genotypes and environments, and the interaction effect, were highly significant (P ≤ 0.001) and (P ≤ 0.01), respectively. The environment main effect accounted for 89.27% of the total yield variation, whereas genotype and G × E interaction effects accounted for 2.12% and 3.31%, respectively.Genotypic superiority index (P i ) and FT3 were found to be very informative for selecting both high-yielding and stable faba bean genotypes. Twelve of the 17 stability parameters,, W i , σ i 2 , EV, P 59 , and ASV, were influenced simultaneously by both yield and stability. They should accordingly be used as complementary criteria to select genotypes with high yield and stability. Although none of the varieties showed consistently superior performance across all environments, the genotype EK 01024-1-2 ranked in the top third of the test entries in 61.5% of the test environments and was identified as the most stable genotype, with type I stability. EK 01024-1-2 also showed a 17.0% seed size advantage over the standard varieties and was released as a new variety in 2013 for wide production and named "Gora". Different stability parameters explained genotypic performance differently, irrespective of yield performance. It was accordingly concluded that assessment of G × E interaction and yield stability should not be based on a single or a few stability parameters but rather on a combination of stability parameters.

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Storage insect pests cause significant losses of food legumes particularly in the Tropics and the Sub-tropics. The most important species of storage insect pests of food legumes include Callosobruchus chinensis, C. maculatus, C. analis, Acanthoscelides obtectus, Bruchus incarnatus, B. rufimanus, B. dentipes, B. quinqueguttatus, B. emarginatus, B. ervi, B. lentis and B. pisorum. Effective post-harvest insect pest control measures should constitute part of the overall crop husbandry practices for preserving the quality of produce. Storage insect pests are commonly controlled using chemical insecticides which, however, bear many drawbacks related to high cost, environmental pollution and food safety risks. Breeding legume crops to improve their resistance against storage insect pests, although having technical limitations, is the best way of overcoming these disadvantages in an environment-friendly manner. In this paper, we present the findings of our extensive reviews on the potential of breeding resistant varieties of food OPEN ACCESS Sustainability 2011, 3 1400 legumes against storage insect pests along with the major technical limitations one would likely encounter and the prospective ways of tackling them.

Plant breeding is one way to confront the challenge of bridging the widening gap between the demand and supply of food. Despite the importance, however, plant breeding has its own negative side effects. The replacement of landraces with a few genetically uniform varieties depletes genetic diversity and provides ideal conditions for diseases and insect pests that called genetic vulnerability. The increasingly growing human population and the subsequently rising demands for more food, on the one hand, and the success of such efforts like the "Green Revolution" from adoption of genetically uniform varieties in many parts of the world, on the other, are the main driving force towards this narrow genetic base. It is, therefore, important to understand the phenomena and plan to minimize the risks from genetic vulnerability. Under marginal conditions where resource-poor farmers dominate, the current plant breeding strategies, variety release, registration and certification procedures leading to genetic uniformity should be reconsidered and some level of genetic diversity should deliberately be maintained in variety development programs. Genetic diversity can be introduced at different levels and in different ways which may include intra-varietal, inter-varietal, inter-parental and inter-specific diversities. Breeding for specific adaptation instead of wide adaptation, systematic spatial and temporal gene deployment, use of inter-specific varietal mixtures and integration of horizontal and vertical resistances have been suggested as solutions.

The common bean (Phaseolus vulgaris L.) is among the most important grain legume crops in Africa. However, the common bean grain is heavily damaged by the Mexican bean weevil (Zabrotes subfasciatus Boheman). This study was conducted to determine the population structure and genome‐wide marker–trait associations of bruchid resistance in the common bean. The phenotypic diversity and population structure of 297 genotypes were analyzed, using the Illumina BARCBean6K_3 SNP BeadChip. The genotypes consisted of landraces, released varieties, breeding lines, and Mexican bean weevil resistant lines. A population structure analysis based on a Bayesian genotype clustering approach classified the 297 genotypes into two subpopulations, namely, Middle American and Andean. Similar population patterns were also observed using principal component analysis. The genome‐wide association study analysis identified 24 single‐nucleotide polymorphisms (SNPs) on nine chromosomes, with a significant (P < 0.05) association with the percentages of adult emergence and seed weight loss. The SNPs located on Pv4 and Pv7 were significantly (P < 0.001) associated with the two traits. Other significant SNPs were identified on other chromosomes of the common bean, but none of them was above the cutoff point (1.00 × 10−4). Therefore, further verification of the SNPs that have a significant marker–trait association at P < 0.05 will be vital, and accessions with these SNPs may be useful as parental materials.

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.

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Chickpea (Cicer arietinum L.) is an economically and ecologically important food legume crop. Ethiopia has a large collection of chickpea germplasm accessions; but, it has not been extensively characterized for desirable sources of agronomic and symbiotic significance for use in breeding programs. A study was conducted at two locations (Ambo and Ginchi) in 2009/2010 to characterize and evaluate Ethiopian chickpea germplasm accessions for symbiotic and agronomic performance. One hundred and thirty-nine germplasm accessions were evaluated with 16 other genotypes including non-nodulating reference checks. Differences among genotypes, locations and genotype by location interaction effects were significant for a number of characters. A number of accessions better performing over the improved genotypes were identified for both symbiotic and agronomic characters. The amount of fixed nitrogen ranged from 13 to 49% in foliage, 30 to 44% in grain and 28 to 40% in total above-ground biomass. Grain yield performance varied from 31 to 70 g per 5 plants and seed size ranged from 82 to 288 g per 1000 seeds. For both symbiotic and agronomic characters, landraces were found to be overwhelmingly superior to introduced genotypes, except for seed size, where the best genotypes were all from exotic sources. The result indicated that Ethiopian chickpea landraces have better genetic potential for improving a number of symbiotic and agronomic characters over the varieties currently in use. Selection of best individuals within and among the accessions would be expected to be effective.