The International Bean Yield and Adaptation Nursery (IBYAN) was first distributed in 1976. This report covers the fourth and fifth series of tests conducted between January and July 1979 (IBYAN 1979A), and between August 1979 and July 1979 (IBYAN 1979B). The material for IBYAN 1979B was divided into two groups according to grain color; one consisted only of black-grained materials, and the other consisted of grain materials of various colors. A total of 130 tests were distributed and data were received from 73 of them.

In this report, both the results of each trial and the combined analysis of all of them are reported. For this analysis, the experiments whose coefficient of variation (CV) did not exceed 35% were taken into account, and only those received up to December 1980, the deadline for receipt of data. Cuadro 3 in the attachment shows the black-grained bean accessions evaluated.