Citation: N/A Interpretive Summary: Tepary beans are related to dry beans (pintos, navies, blacks, kidneys) and useful traits have been moved from one to the other. Tepary beans themselves are grown on thousands of acres worldwide. We evaluated select tepary bean germplasm for reaction to bean golden mosaic virus, a devastating disease of common bean, in tropical North and South America. Some lines showed higher levels of tolerance to the disease than others. These tolerant lines may enable production of tepary bean in regions mildly affectly by the virus, and may provide a useful trait for the improvement of dry beans.
Technical Abstract: Cultivated tepary bean (Phaseolus acutifolius A. Gray var. latifolius Freeman) has potential for production during the hot, dry seasons in the tropics. Bean golden mosaic virus (BGMV), however, seriously limits production of Phaseolus spp. in such environments. Twelve select tepary bean were evaluated for reaction to BGMV across four field nurseries near Isabela, Puerto Rico. Disease reaction was principally determined by measurement of seed yield (kg ha**-1) and weight (g 100/seeds). All tepary beans possessed some tolerance to BGMV, as they produced comparatively moderate seed yield despite expression of severe foliar yellow mosaic symptoms. On average, tepary bean yielded 133% of the BGMV resistant dry bean (Phaseolus vulgaris L.) control `Dorado'. Four teparies expressed superior tolerance to BGMV as they yielded above the trial mean in at least three of four trials. Harvested seed quality was uniformly poor across all lines, averaging 18% less weight than in the non-BGMV trials. The combination of the observed tolerance with escape mechanisms and cultural disease control practices may enable production of tepary bean in regions and seasons that experience moderate to severe BGMV epidemics.