苹果根腐病是病果的根部病害,常于春季地温上升时发病。发病时,花后叶片不鲜,呈暗绿色,不久叶片迅速萎蔫,继而由小枝开始,向下逐渐枯死.发病重时可引致死树.根腐病病源,是寄生真菌,在树体健壮时,虽染菌但不发病。这是因为健壮树体具有较强的抵抗力,能够限制病菌的蔓延,树体不显病。如树体衰弱,则抵抗力差,发病柳率就高。因而,防治苹果树根腐病的关键,是加强土、肥、水管理,促 Apple root rot is the root cause of diseases and diseases, often in the spring when the temperature rise. Occurrence, the flower is not fresh leaves, dark green, and soon leaves rapidly wilting, and then by the branchlets, gradually dying down.When the incidence of dead can lead to dead tree root rot disease, is a parasitic fungi, when the tree is robust Although bacteria, but not disease. This is because the robust tree has strong resistance, can limit the spread of germs, the tree is not obvious disease. If the tree is weak, then the resistance is poor, the incidence is high. Therefore, the key to preventing and curing apple tree root rot is to strengthen soil, fertilizer and water management and promote