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Large seeded Andean dry beans (Phaseolus vulgaris L.) are most preferred in Africa. However, low soil fertility and increasing drought stress conditions due to climate change are among the challenges faced by farmers in this region. The purpose of this study was to identify Andean genotypes with yield stability and to identify the best environments for selection of this trait. GGE-Biplot analysis was used to examine 183 Andean bean genotypes in Tanzania. Results indicated significant environment (E), genotype (G) and genotype x environment (GE) effects for seed yield. The environment explained 46%, genotype 20%, and GE 34% of the total (G + E + GE) variation. Two principal components explained 41.21% (PC1) and 26.35% (PC2) of GGE sum of squares. The Andean genotypes, ADP-102 (Jessica)- purple mottle, large seed, bush plant habit, released by Selian Agriculture Research Institution (ARI) in Tanzania; ADP-220 (G5625)- red, large seed, vine plant habit, from Central America; ADP-276 (G13654) - brown, medium seed, vine, from Mexico; and ADP-648 (‘Red Kloud’) large red kidney, with bush plant habit, were stable across environments and can be recommended for general adaptation across environments. An individual location for selection for yield stability was not identified, thus justifying the continued need for multiple test sites.

INTRODUCTION Nitrogen (N) deficiency is present in common bean (Phaseolus vulgaris L.) fields in most production regions in Central America and the Caribbean (CA/C), especially on small hillside farms where no or sub-optimum levels of fertilizer are used. Under these conditions, Rhizobium inoculants could represent a cheap and effective input to increase bean yield. Despite the potential benefits from increased biological nitrogen fixation, Rhizobium inoculation is rarely used by farmers in CA/C. Nodulation and nitrogen fixation (N2) of bean cultivars in response to Rhizobium inoculation is quite variable due to several biological and edaphic factors (Graham et al. 2003). On the other hand, the response of different bean cultivars and germplasm accessions to different Rhizobium species and strains that nodulate and fix N2 is often difficult to measure on farms. A better understanding of specific bean host-plant-Rhizobium strain interactions would facilitate the selection of superior symbionts with greater response to inoculation and increase bean productivity in N-limited soils