Variability within the common bean phaseolus vulgaris germ plasm

Abstract

Genetic variability is the most important aspect in any crop breeding. Bean production in Uganda is characterized by
much variation in environmental conditions, cropping systems, preferences and constraints. The breeding programme
aims at improving national bean production through provision of superior varieties released periodically and also
conserve genetic variability ex-situ. The modern agricultural tendency of exclusive use of widely adapted and widely
diffused varieties enhances local adaptation and performance at the expense of genetic variability. Farmers' varietal
selection criteria were found to be variable and partially responsible for genetic variability on-farm. However, with
introduced improved cultivars narrowing of genetic variability on-farm may compromise production stability for
farmers. The germ plasm collected over the past years represent the variation in morphological as well as agronomic
traits within the varieties grown in various districts of the country. The implications of the above factors and the
characterization of the available germ plasm form the discussion basis of this paper.