近年来在10年生以上的国外松林中,相继发生根腐病,严重危害着这些松林。一、病害的症状与病原物国外松根腐病是一种真菌性病害,树木感病后,不抽新梢,从枝桠基部针叶开始变黄,逐步向上蔓延,直至整株枯死。树干基部出现流脂现象;地下部分表现为根系流脂,结成脂块,根系干枯腐烂,病根皮层与木质部脱离。病原菌首先从根尖侵入,沿根部逐渐蔓延到根颈部分,导致根系腐烂。解剖病根可见明显病斑。病原菌为土壤中的杂居菌镰刀菌 In recent years, more than 10-year-old pine forests in the world, have occurred in the root rot, a serious threat to these pine forests. First, the disease symptoms and pathogens Foreign pine root rot disease is a fungal disease, the trees after the disease, do not smoke new shoots, starting from the branches of the needle stalks turn yellow, and gradually spread until the whole plant died. Trunk flow at the base of the phenomenon of fat; the underground part of the performance of the root flow fat, the formation of fat, dry roots rot, diseased cortex and xylem detachment. The pathogen first invades from the root tip and gradually spreads to the root neck along the root, causing root decay. Anatomy of the root visible obvious lesion. Pathogenic bacteria in soil Fusarium