Identification, Pathogenicity, and Sensitivity to Fungicide of Colletotrichum Species That Causes Walnut Anthracnose in Beijing

Walnuts (Juglans regia L.) are a major food crop in Beijing. Recently, walnut anthracnose has become serious problem plantations of Beijing, and the diversity pathogens that cause this disease is poorly understood, making targeted treatment difficult. This study investigated incidences seven districts Beijing (Changping, Fangshan, Haidian, Huairou, Mentougou, Miyun Pinggu). A total 377 isolates Colletotrichum spp. were obtained from infected leaves fruits. Morphological observation multigene phylogenetic analysis genes ACT, CAL, CHS-1, GAPDH, ITS TUB2 revealed consisted six species, C. aenigma, fructicola, gloeosporioides, siamense, liaoningense sojae. Among these, gloeosporioides was dominant and, for first time, sojae found to walnuts. Sensitivity tests showed prochloraz SYP-14288 had strongest inhibitory effect on mycelial growth. These findings have clarified species these which provides scientific basis diagnosis control anthracnose.