A greenhouse screening technique for bean golden mosaic virus

Abstract

Dry bean (Phaseolus vulgaris L.) yield in the Caribbean and snap bean production in southern Florida are threatened by bean golden mosaic virus (BGMV). Effective screening techniques are needed in order to transfer BGMV resistance into red kidney, red mottied and snap beans. A greenhouse inoculation method for BGMV using viruiiferous whiteflies (Bemisia tabaci Genn.) has been developed. The use of this inoculation method insures that bean plants are inoculated at the same stage of development with a uniform amount of inoculum. In the greenhouse, the reaction of bean plants to BGMV could be determined within 30 days after planting, whereas field evaluations require up to 65 days. In addition, the BGMV reaction of bean genotypes inoculated in different experiments was found to be repeatable. In susceptible genotypes, such as PC50, typical BGMV symptoms began to appear between five to eight days after inoculation (DAI). In the resistant line DOR364, symptoms did not begin to appear until 10 to 12 DAI and the severity of the symptoms was less than in susceptible genotypes. Pompadour G and lines derived from crosses with DOR303 showed a dwarfing response when inoculated with BGMV.The BGMV resistant lines derived from crosses with A429 did not develop symptoms when inoculated with the viruliferous whiteflies.This greenhouse inoculation technique may facilitate the effort to combine different forms of BGMV resistance.