IDENTIFICATION OF EFFECTIVE INDICATORS OF ERECT PLANT ARCHITECTURE IN DRY BEAN

Applying the concept of ideotypes in a breeding strategy presupposes that the breeder already knows what traits to select. This study was conducted to determine the substantive indicators of erect plant architecture in dry bean (Phaseolus vulgaris L.). In the first of two field studies, data on 17 architectural traits were collected at two locations on parental plants and progenies originating from five distinct cycles of a phenotypic recurrent selection program. In the second study, similar data were collected at one location on 480 F3 lines from six crosses. A stepwise multiple regression procedure was used to determine traits that are effective indicators of erect plant architecture. Hypocotyl diameter, plant height, branch angle, and pods on the main stem and especially in the midsection were selected for inclusion in the regression model, suggesting their important contributory role in a dry bean ideotype. Dry bean breeders should emphasize these four traits for effective selection and efficiency in a breeding program for erect plant architectures.