MORPHOLOGICAL AND PHENOLOGICAL CHARACTERIZATION OF WILD BEAN (Phaseolus) SPECIES

Abstract

In order to generate useful information for the increase and conservation of accessions of wild bean, a morphological and phenological characterization of 12 species of the genus Phaseolus was performed. The species of tropical and subtropical origin were grown in a greenhouse and the native tempered or temperate cold sites were grown under a mesh shade. In the characterization the common bean (Phaseolus vulgaris L.) varietal descriptors of the Inspection and Certification of Seed Service from México as well as the scale of growth stages established for the International Center for Tropical Agriculture from Colombia. A plot of a single row of 4 m in length per species was used and 39 order qualitative and quantitative variables were recorded. The value of quantitative, is the average of 10 records. Great morphological and phenological variability between species were observed. The length of primary leaves ranged from 1.4 to 5.4 cm and leaflet of 3.1 to 8.5 cm; the length of pod 1.2 to 6.3 cm, the number of pods per plant of 21 to 314, and seed 3.0 to 7.9 mm length; pollen size varied from 41.7 to 55.48 μm. Six of the 12 species showed cotyledons epigeal, six pink hypocotyl, eight purple flowers and eight of the 12 taxa perennial cycle. In early stages of development the species showed similar response, whereas in the reproductive phase, the species showed notable differences in the days to reach a stage and its duration. Bean species were grouped into two main sets related to the size of the plant and biological cycle; the biggest similarity arose between P. vulgaris and P. acutifolius, P. microcarpus and P. macvaughii, and P. nodosus and P. scrobiculatifolius. The information obtained can support actions for increases in seed, conservation, efficient use and genetic improvement.