苹果是四川的主要果树之一。为害苹果枝干的病害有苹果腐烂病、干腐病和轮纹病等。1974年在蓬溪县回马地区的“麻皮”(果品名称青苹)树上新发现一种严重为害大枝及主干的真菌病害。此病能造成枝干腐烂,影响果树寿命和产量。当时调查4个果园均有发生、为害,最重的果园病株率达55.0％,部分病树已死亡。经过鉴定,认为是苹果树疱溃疡病Nummularia discreta(Schw.)。 Apple is one of the main fruit trees in Sichuan. Diseases of apple branches damage apple rot disease, rot and rot disease and so on. In 1974, a serious damage to the branches and stems of fungal diseases was newly discovered in the tree of “Ma Pi” (fruit name Qing Ping) in the Hui region of Pengxi County. The disease can cause rotting branches, affecting fruit tree life and yield. Four orchards were investigated at that time, causing damage. The heaviest orchard disease rate reached 55.0% and some diseased trees were dead. Identified as Nummularia discreta (Schw.), An apple blister canker.