玉米茎腐、鞘腐、穗腐病中不同镰孢菌间关系研究

摘要

[Objective] The objective of this study is to understand the pathogenicity of stalk,sheath and ear rots pathogens.[Method] Three kinds of methods which are soil inoculation,puncture inoculation and spore suspension inoculation were used.[Result] Stalk rots of maize was mainly caused by Fusarium proliferatum and F.verticillioides,and direct inoculation confirmed that F.graminearum caused ear and sheath rots of maize and F.oxysporum caused many types of rots by accompanied infection.[Conclusion] By inoculation of the pathogens onto maize sheath,ear and stalk at various periods,plant height,lesion size,grain fullness of maize were observed for analyzing their pathogenicity,best infection period and the relationships among the pathogens of stalk,sheath and ear rots.It is concluded that all of the four Fusarium pathogens could infect stalk,sheath and ear without parts specialization through wound although their pathogenicity varied with different infection periods.%[目的]为了明确不同镰孢菌对玉米茎腐病、鞘腐病和穗腐病的致病性.[方法]采用土壤接菌、穿刺接菌和孢子悬浮液接菌的方法.[结果]证明层出镰孢菌(Fusarium proliferatum)、轮枝镰孢菌(F.verticillioides)可引起玉米茎腐病,禾谷镰孢菌(Fgra-minearum)可引起穗腐病、鞘腐病,而尖孢镰孢菌(Foxysporum)则通过复合侵染引起病害.[结论]将各类镰孢菌分别接种不同生育期的玉米植株,观察株高、病斑大小、玉米发育程度和籽粒的形成情况,研究各镰孢菌菌株对玉米植株的影响程度,分析各菌株的致病力,最佳侵染时期及茎腐、鞘腐、穗腐之间的侵染关系,证明玉米茎腐、鞘腐、穗腐之间病原菌侵染部位没有特异性,不同时期侵染引起的茎腐、鞘腐及穗腐发病程度不同.