PATTERNS OF GENETIC DIVERSITY IN LANDRACES OF COMMON BEAN (PHASEOLUS-VULGARIS L.) FROM GALICIA

Knowledge of patterns of genetic diversity among existing cultivars he lps to broaden the genetic base of new cultivars and maximizes the use of available germplasm resources. This study examined the organizatio n of diversity for morphological traits in 66 landraces of cultivated common bean (Phaseolus vulgaris) from Galicia and its relationship wit h phaseolin seed protein diversity. Data on growth habit, seed and pod trails obtained from field evaluations at two locations during the 19 89-91 cropping seasons were subjected to multivariate statistical anal ysis. Cluster analysis based on 14 quantitative variables and five qua litative variables identified 11 groups. The landraces were also chara cterized by phaseolin electrophoresis. The results allowed separation of these landraces into Middle and Andean American groups, which could be further divided into at least eight groups within the Andean Ameri can cultivars and three within the Mesoamerican cultivars. These group s in turn corresponded to the previously described races Nueva Granada and Peru of South American origin, and races Durango, Jalisco and Mes oamerica from the Middle American domestication centre. These results confirm the existence of two major groups of germplasm in the cultivat ed common bran landraces from Galicia, Mesoamerican vs. Andean America n.