Wax apple (Syzygium samarangense) is an important fruit crop in Taiwan. Severe decline of wax apple trees was noticed in 2003 in northern suburban Taiwan. A fungus consistently isolated from diseased twigs of declining wax apple trees, was identified as Fusarium solani based on morphological characteristics. Fusarium solani from wax apple shared 92.0 to 98.6% and 93.0 to 99.6% intraspecific sequence similarity of ITS and 28S, respectively, with those available in GenBank. Upon inoculation, the isolated F. solani caused twig blight on healthy wax apple trees, and F. solani was reisolated from the diseased twigs, thus fulfilling Koch's postulates. All the control trees remained healthy throughout the experiment. Numerous microconidia of F. solani produced on the cut surfaces of diseased twigs under moist conditions were considered to be the main inoculum source for secondary infection of diseased trees and primary infection of healthy trees.
