Fertile backcross and allotetraploid plants from crosses between tepary beans and common beans

Abstract

Crosses were made between 14 lines of tepary beans (Phaseolus acutifolius A. Gray) and 15 lines of common beans (P. vulgeris L.) in an attempt to transfer characters from teparies to common beans. Pods with hybrid embryos remained on common bean plants 6 days longer than on teparies before aborting. Twenty-nine of the 39 mature F1 hybrid plants reared by embryo culture had either or both the common bean, ‘Masterpiece’, or tepary P1321638 as one parent. Among 16 mature F1 genotypes, five produced BC1 and/or allotetraploid progeny. Fertility of some backcross and allotetraploid lines increased with selfing or a second backcross generation.