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梨锈病又名梨赤星病,是南方梨树上的重要病害。由于今年春季雨水多,我省不少地区的梨锈病发生严重,如宣汉、苍溪、会理等地的不少梨园的发病率几乎是100%,果农反应十分强烈。此病为转主寄生病害,病菌除寄生为害梨树外,尚需在桧柏等松柏科树木上寄生一段时间,方能完成其侵染循环。梨锈病可引起叶片早枯,幼果畸形、早落,对梨的产量和品质影响很大,应引起足够的重视。一、症状梨锈病主要为害梨树的叶片和新梢,严重时也能为害幼果。叶片受害,开始在叶正面发生橙黄色、有光泽的小斑点,然后逐步扩人,直径可达3—6毫米,表面密生针头大的橙黄色小粒点,此为病菌的性孢子器,内有大量的性孢子。小粒点逐渐变黑,病斑变肥厚,背面隆起,正面微陷。在叶背隆起部位长出
Pear rust Also known as pear brown spot, is an important disease on the southern pear. Due to the heavy rainfall in spring this year, pear rust in many areas of our province is serious. For example, the incidence of many pear orchards in Xuanhan, Cangxi, Huili and other places is almost 100%. The response of farmers is very strong. The disease is transferred to the main parasitic disease, in addition to parasites parasitic pests outside the tree, still need to cypress cypress cypress trees such as parasites for some time before they can complete the cycle of infection. Pear rust can cause leaf early withered, young fruit deformity, early fall, a great impact on the yield and quality of pear, should cause enough attention. First, the symptoms Pear rust mainly pear leaves and new shoots, serious damage to young fruit. Leaf damage, beginning in front of the leaves orange yellow, glossy small spots, and then gradually expand the diameter of up to 3-6 mm, surface dense needle large orange-yellow small particles, which is the germ sporulation device, which has A lot of spores. Small particles gradually darken, lesion becomes hypertrophy, back bulging, positive subsidence. Back up in the back part of the leaves