论文部分内容阅读
梨树疫腐病又叫颈腐病,是近年来在冀中南部出现的一种新病害,特别是遭受水灾的梨园发病重、传播快,幼树死亡率高,具有毁灭性。一、病原及传播。病原是土壤习居菌侵染致病。这种病由土壤带菌随地面流水传播。树干基部嫁接口、机械伤、冻伤是病菌的主要侵染点。二、发病症状。该病主要发生在幼树主干基部,砧穗接口以上。病部树皮呈黑褐色,皮层逐渐组织坏死,于缩凹陷,当病斑绕树干一周时,形成层被破坏,全树死亡。病树一年生枝衰弱,秋季叶片变红,逐渐变褐而脱落。果实受害后,产生不明显病褐斑,部分果皮与果肉分离,病果略有弹性,极易脱落。
Pear blight known as rot disease, is a new disease in southern Hebei in recent years, especially in flood-prone pear orchard, rapid transmission, sapling mortality, destructive. First, the pathogen and spread. Pathogen is caused by soil habitat infection. The disease is spread by soil-borne water from the ground. Trunk base grafting, mechanical injury, frostbite is the main infection of bacteria. Second, the incidence of symptoms. The disease occurs mainly in the sapling trunk base, scion spike interface above. Sick bark was dark brown, cortical tissue necrosis, shrinkage depression, when the lesion around the trunk a week, the formation layer is destroyed, the whole tree died. Diseased tree annual branches weak, autumn leaves turn red, gradually brown and fall off. After the fruit is damaged, it produces obvious brown spots, part of the peel and pulp separation, the disease is slightly flexible, easy to fall off.