MORPHO-AGRONOMIC DIVERSITY OF THE RUNNER BEAN IN THE CENTRAL-EASTERN HIGHLAND PLATEAU OF PUEBLA

Abstract

The studies of genetic diversity enable its quantification and the identification of actions needed for its conservation and use. In Phaseolus coccineus L., even though several diversity studies have been conducted, in none of them the accessions have been evaluated in the area where they were collected, nor have included a large sample of local populations from the central-eastern highland plateau of Puebla, the main production area in México. The objective of this work was to determine the level of morpho-agronomic variation present in the local populations of runner bean cultivated in the aforementioned region, and to identify the main morpho-agronomic traits related to the found diversity. A total of 31 local populations were evaluated, as well as five controls. The evaluation was conducted at two sites within the area of collection, using a lattice experimental design with two replications per site. Data were recorded on 34 morpho-agronomic traits, dealing with attributes of emergence, seedling, leaf, flower, plant, pod, seed and grain yield. The combined analysis of variance revealed that the morpho-agronomic diversity is large, showing that the variation is present in all the structures of the plant, but mostly in variables measured on flower, pod and seed. The cluster and principal components analyses allowed the identification of four groups of populations, differentiated basically by earliness, seed and flower color, and complemented by vigor and height of plant, length of central leaflet and petiole, seed shape and weight of 100 seeds. It is concluded that the morpho-agronomic diversity present in the local populations of runner bean is large, and that days to flowering, flower color and seed color, are the most important traits to explain the existing diversity.