COMPARISON OF SELECTION METHODS FOR DRY BEAN POPULATIONS DERIVED FROM CROSSES BETWEEN GENE POOLS

New approaches are needed to broaden the genetic base and improve the yield potential of large-seeded ed beans (Phaseolus vulgaris L.). The objectives of this research were to compare the effectiveness of two recurrent selection methods to develop indeterminate red-seeded bean populations that yield more than determinate red-seeded varieties. The original base population was produced from crosses between genotypes from the Andean and Middle American gene pools. The performance of the populations developed by recurrent selection was tested in field trials conducted over three growing seasons in Puerto Rico. Both recurrent selection with F-2 evaluation and recurrent selection with F-5 evaluation were successful in developing tropically adapted indeterminate bean populations having seed type and seed size suitable for the Caribbean. Recurrent selection with F-5 evaluation produced a larger number of indeterminate populations with greater seed yields than the determinate check cultivars. The greater seed yield of these indeterminate populations was attributed to longer reproductive periods and a greater number of days to physiological maturity. Heterosis for seed yield, the large amount of segregation for seed type and agronomic traits, and the lack of evidence of a linkage between small-seed size and erect, indeterminate plant architecture favor the use of recurrent selection with advanced generation evaluations to improve bean populations derived from different gene pools.