1发生特点1.1残留田间地表和玉米秸秆内残留在病叶组织中的菌丝体及附着的分生孢子均可越冬,成为第2年的初侵染来源。玉米生长季节,越冬菌源产生孢子,随雨水或气流传播到玉米叶片上,适宜温、湿度条件下萌发入侵。病菌侵入后迅速扩展,约经14d,即可引起局部萎蔫,组织坏死,进而形成枯死病斑,潮湿的气候条件下,病斑上可产生大量分生孢子,随气流传播,进行多次再侵染,造成病虫害流行。 1 Occurrence characteristics 1.1 Residues in the field and corn stalk residue leaves in the diseased leaves of mycelium and attached conidia can wintering, becoming the source of the first two years of infection. During the growing season of maize, the spores of overwintering bacteria spores propagate to the leaves of maize with rain or air currents and are suitable for germination and invasion under temperature and humidity conditions. After the invasion of bacteria rapidly expanding, about 14d, can cause local wilting, tissue necrosis, and thus the formation of dead spots, humid climatic conditions, the lesion can produce a large number of conidia, with the air flow, repeated re-invasion Dyeing, causing pests and diseases.