Study concerning the variability of the main climbing bean characteristics under the environmental conditions of south-eastern Romania

In Romania, there are many traditional vegetable areas that are cultivated with local bean populations. In 2010, a national program was initiated in order to preserve and valorize this species. The research led to a germplasm collection that contains over 150 accessions, and it identified greater variability in the main plant characteristics of climbing bean (Phaseolus vulgaris L. var. communis) compared with dwarf bean (Phaseolus vulgaris L. var. nanus). This paper presents a comparative study, in open-field conditions, of 10 local populations of climbing bean that presented a high degree of phenotypical instability during 2011-2013. L₅₈ presented five different biotypes since the first year of culture, which were harvested and cultivated separately during the following years. Thus, there were plants with green, light violet and violet pods, and two biotypes that had red secondary color, and the main color was green and respectively yellow. The results obtained, corroborated by the floral anatomy of some local populations, show the presence of cross-pollination of climbing bean plants.