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玉米茎基腐病是由病原菌复合侵染所引起的病害,在山西省分布广、危害重,是玉米的主要病害之一。此病可以危害幼苗,但主要发生在生长后期。其症状分急性型和慢性型,前者整株很快青枯死亡:后者一般在吐丝后发病,较常见,一般表现为:叶片由下向上逐渐枯死,发病后期茎基纵剖面髓部变色收缩,果穗下垂,易倒伏。经试验证明:其主病原(uajor pathogen)为串珠镰刀菌(Fusarium moniliforme)、串珠胶孢变种(F. moniliforme var.subglutinans)、禾谷镰刀菌(F. graminearum)、长蠕孢菌(Helminthosporiumsp.),其中串珠镰刀菌致病力最强。通过玉米不同发育阶段的连续分离证明:四种主病原都有潜伏侵染现象,串珠可以扩展到茎基第三节间,但并不扩展到穗部。次病原(Minor pathogen为木贼镰刀菌(F. equiseti)、交链孢菌(Alternaria spp)、半裸镰刀菌(F. semitectum)、多隔镰刀菌(F. decemcellulare)、弯角镰刀菌(F. camptoceras)等,它们是在主病原侵入后才侵入寄主的,本身致病力弱,但与某些主病原有协生作用,可加重病害的发生。
Corn stem rot is a disease caused by complex infection of pathogenic bacteria, widely distributed in Shanxi Province, endangering heavy, is one of the major diseases of corn. The disease can endanger seedlings, but mainly in late growth. The symptoms of acute and chronic sub-type, the former rapid death of whole plant dead: the latter generally after the onset of silkworm, the more common, generally as follows: the leaves gradually wither from the bottom up, late onset of the longitudinal section of the liver stem discoloration Shrinkage, ear hanging, easy to lodging. It has been proved through experiments that the major pathogens of the pathogen are Fusarium moniliforme, F. moniliforme var.subglutinans, F. graminearum and Helminthosporium sp. Among them, Fusarium moniliforme has the strongest pathogenicity. The continuous separation of different stages of development of corn proved that all four major pathogens had latent infection and beaded beads could extend to the third node of stem base but did not extend to the ear. Minor pathogen is F. equiseti, Alternaria spp, F. semitectum, F. decemcellulare, Fusarium oxysporum (F camptoceras), etc., they invade the host after the invasion of the host, its own pathogenicity is weak, but synergistic with some of the main pathogens can exacerbate the disease.