Breeding for common bacterial blight resistance in common bean (Phaseolus vulgaris L.) in Ethiopia.

Doctoral Degree. University of KwaZulu-Natal, Pietermaritzburg.Abstract available in PDF

Grouping of environments for testing navy bean in Ethiopia

Common bean variety selection within its production environment is often challenged by the occurrence of significant genotype-by-environment interactions (GEI) in the variety development process. Grain yield performance of 16 navy bean (Phaseolus vulgaris L.) lines was tested in a multi-environment variety trial during 2010 and 2011 main growing seasons of Ethiopia. Field experiments were conducted in Randomized Complete Block Design (RCBD) with three replications in 14 rainfed environments of the major common bean growing areas. The objectives were to assess the line by environment interactions (LEI), determine stable genotypes, and grouping of test environments. Significant differences were found among the lines for grain yield on each environment and combined over environments. The combined analysis of variance across environments indicated that both environment and LE interactions were significantly influenced lines yield. All interactions in relation to L×E showed high significant difference (P<0.01) for grain yield. Statistical methods as AMMI, GGE and some stability parameters were used to describe the LE interaction and to define stable lines in relation to their yield. The highest yield (2435 kg ha-1) was obtained from the line ICA BUNSI X SXB 405/1C-C1-1C-87. The stability analysis also identified lines ICA BUNSI X SXB 405/1C-C1-1C-87 and ICA BUNSI X SXB 405/1C-C1-1C- 37 as the most stable lines. Lines identified as superior differed significantly from the standard varieties and can be recommended for use by farmers in the bean growing areas of Ethiopia. Cluster analysis, based on grouping of locations showed that Melkassa, Alemtena and Haramaya as potential and high yielding, but Jimma, Bako, Pawe, Areka, Assosa and Sirinka as low to medium yielding locations

Analyses of African common bean (Phaseolus vulgaris L.) germplasm using a SNP fingerprinting platform: diversity, quality control and molecular breeding

Common bean (Phaseolus vulgaris L.) is an important staple crop for smallholder farmers, particularly in Eastern and Southern Africa. To support common bean breeding and seed dissemination, a high throughput SNP genotyping platform with 1500 established SNP assays has been developed at a genotyping service provider which allows breeders without their own genotyping infrastructure to outsource such service. A set of 708 genotypes mainly composed of germplasm from African breeders and CIAT breeding program were assembled and genotyped with over 800 SNPs. Diversity analysis revealed that both Mesoamerican and Andean gene pools are in use, with an emphasis on large seeded Andean genotypes, which represents the known regional preferences. The analysis of genetic similarities among germplasm entries revealed duplicated lines with different names as well as distinct SNP patterns in identically named samples. Overall, a worrying number of inconsistencies was identified in this data set of very diverse origins. This exemplifies the necessity to develop and use a cost-effective fingerprinting platform to ensure germplasm purity for research, sharing and seed dissemination. The genetic data also allows to visualize introgressions, to identify heterozygous regions to evaluate hybridization success and to employ marker-assisted selection. This study presents a new resource for the common bean community, a SNP genotyping platform, a large SNP data set and a number of applications on how to utilize this information to improve the efficiency and quality of seed handling activities, breeding, and seed dissemination through molecular tools

Planteome/CO_335-common-bean-traits: 1st release

<p>This is the first release of the Common Bean repository</p&gt