Heritability and Correlations Among Popping Characteristics and Seed Weight in a Broad-based Temperate-adapted Nuña Bean (Phaseolus vulgaris L.) Population

Abstract

Nuña beans are a type of common bean (Phaseolus vulgaris L.) from the Andean region of South America that possess the unique property of popping. To develop temperate-adapted nuña bean cultivars, knowledge is needed regarding the inheritance and relationships among popping characteristics and seed weight. Nuña bean landraces are often photoperiod-sensitive; thus, to obtain estimates of the genetic parameters associated with seed characteristics, populations adapted to the long days of northern temperate climates were developed. Four sets of 10 families, sampled from a temperate-adapted population, were crossed in a Design II mating design. The heritabilities of seed weight, popping percentage, and the coefficient of expansion were relatively high, 0.77 ± 0.04, 0.87 ± 0.07, and 0.74 ± 0.09, respectively. Large positive phenotypic (0.773) and additive genetic (0.539) correlations were observed between popping percentage and the coefficient of expansion. Correlations with seed weight were not significant. The results indicate that direct selection for either increased popping percentage or coefficient of expansion will simultaneously improve both traits with little or no change in seed weight.