黑斑病是梨树上的重要病害之一,在主要梨产区普遍发生,梨树整个生育期及各个部位都会发病。叶片染病,先出现小黑斑,后逐渐扩大至直径1厘米的近圆形,微带有淡紫色轮纹,湿度大时表面产生黑色霉层(病菌分生孢子梗和分生孢子);幼果染病,果面形成黑色圆形小斑,后逐渐扩大,略凹陷,产生黑霉,果实长大时果面龟裂,裂缝可深达果心。 Black spot disease is one of the most important diseases on pear trees. It is common in the main pear producing areas. Pear trees will develop throughout the growth period and in all parts of the tree. The leaves appeared first small dark spots, and then gradually expanded to nearly circular 1 cm in diameter with a slight lavender wheel pattern. When the humidity was high, the black mold layer (the conidiophores and conidia of pathogenic bacteria) were formed on the surface. Fruit disease, the fruit surface to form a small round black spots, and gradually expanded, slightly depressed, resulting in black mold, fruits grow up when the fruit surface cracks, cracks can reach deep fruit heart.