‘Bella’ (Reg. No. CV‐321, PI 681720) is a multiple disease–resistant white‐seeded common bean (Phaseolus vulgaris L.) cultivar adapted to the humid tropics developed and released cooperatively by the University of Puerto Rico Agricultural Experiment Station and the USDA‐ARS. Bella combines resistance to Bean common mosaic virus (BCMV), Bean common mosaic necrosis virus (BCMNV), Bean golden yellow mosaic virus (BGYMV), common bacterial blight, and web blight. The performance of Bella was evaluated across 5 yr in eight environments in Puerto Rico. It tolerated higher temperatures and performed well in soils with low fertility. Bella was developed by pedigree selection to the F7 generation based on superior agronomic traits (early maturity, erect plant architecture, and good pod set) and commercial seed type. Marker‐assisted selection was used to identify the presence of the bgm‐1 gene and the SW12 quantitative trait locus for resistance to BGYMV and the I and bc‐3 genes for resistance to BCMV and BCMNV. Greenhouse inoculations were used to confirm the presence of the I and bc‐3 genes and to screen the line for reaction to strains of common bacterial blight. Mean seed yield of Bella was comparable to the check cultivars. Bella produced among the highest yields in the Bean Adaptation to Stress Environments (BASE) trials planted at Isabela, PR. Bella should allow the successful production of common beans in Puerto Rico throughout the year in soils with lower N fertility. It should also be useful as a parent to enhance the virus, common bacterial blight, and web blight resistance of white, small red, and black beans.

Introduction. Common beans (Phaseolus vulgaris L.) in Central America and the Caribbean are often produced on low fertility soils which reduces crop yield. Bean breeding programs need to identify genotypes that have superior adaptation to these conditions. Objective. Identify Mesoamerican bean germplasm lines with superior adaptation to low soil fertility. Materials and methods. The performance of twenty-seven Mesoamerican bean (Phaseolus vulgaris L.) lines from the Bean Abiotic Stress Evaluation (BASE) 120 panel were evaluated in an unfertilized oxisol at Isabela, Puerto Rico over five growing seasons (four-year period from 2015-2018). The lines were inoculated with a mixture of Rhizobium etli and R. tropici to promote symbiotic nitrogen fixation (SNF). Results. Four lines produced mean seed yields >1,200 kg ha-1 and had estimates of nitrogen derived from the atmosphere (NDFA) >50 %. Greater nodule number was positively correlated with % NDFA, later maturity and seed yield. The heat and drought tolerant small red cultivar ‘Rojo Chortí’ and the heat tolerant white cultivar ‘Verano’ had among the smallest apparent C isotope discrimination values suggesting greater water use efficiency. Among the elite lines in the trial, root rot damage was minimal and the basal root growth angles were intermediate (40-60 %), which favored the uptake of water and soil nutrients. Conclusion. Mesoamerican bean lines with superior seed yield and enhanced symbiotic nitrogen fixation in a low fertility soil were identified. Many of these lines also possess resistance to other biotic and abiotic factors that limit bean seed yield in Central America and the Caribbean.