Phenotypic characterization of the exotic Genotypes and widely cultivated common bean Genotypes in Southern Highlands of Tanzania

Abstract

Common bean (Phaseolus vulgaris L.) is a key legume crop that is prized for its nutrition, adaptability, and ability to promote sustainable agriculture through nitrogen fixation. In Tanzania southern highlands, common bean characterization creates limitations to its potential yield and responsiveness to varying environments. In this research, phenotypic characterization of 12 popular common bean genotypes in southern highlands of Tanzania and imported genotypes from CIAT Colombia were studied. In the evaluation, promising genotypes with desirable phenotypic characteristics were identified. The genotype 22ACC02333 was characterized by strong growth and heavy leaf intensity, 22ACC03221 were characterized by medium-sized leaves and heavy curvature of pods, 22ACC02881 was characterized by pale green leaves with pigmented stems, and 22ACC02433 was characterized by spreading growth and twining habit. All the above genotypes shown favorable phenotypic characters of flowers, yielding, testa color, and heavy growing structure, indicating their suitability for future breeding programs. The study highlighted the market worth of such genotypes since they complied with market requirements for the uniformity of pod size, seed pigmentation, storage capacity, and yield potential, making them suitable for consumer and processing uses. Further, the phenotypic characteristics scored for these genotypes rate them with ability to withstand against biotic and abiotic stress which are vital for small scale farmers’ common bean production in the regions. The study is a strategic manual to breeding programs seeking to develop better productive, resistant and marketable improved varieties that are valued materials for viable agriculture development across Tanzania's southern highlands and other areas affected by climate variability.