葡萄穗轴褐枯病主要危害葡萄果穗幼嫩的穗轴组织 ,已成为葡萄生产上的一种主要病害之一。1 .危害症状　病源菌在 5月上旬葡萄花序分离期侵染发病 ,发病初期先在幼穗的分枝穗轴上产生褐色水浸状斑点 ,迅速扩展后致穗轴变褐色 ;5月中下旬花期是危害高峰期 ,果粒失水萎蔫或脱落。 Cotyledon sheath blight is one of the major diseases in grapes production, which mainly endangers the young cob tissue of grape berries. 1. Harmful symptoms of pathogenic bacteria in early May inflorescence isolation of inflorescence onset, the early onset of panicle spike in young panicle brown spots, rapid expansion of the brown shaft brown; late May Florescence is the damaging peak, fruit wilting or loss of water.