【作者】 樊少华；

【导师】 李敏权；

【作者基本信息】 甘肃农业大学 ， 植物病理学， 2007， 硕士

【摘要】 针对近年来苜蓿镰刀菌根腐病普遍发生并逐年加重的现状,本试验以甘肃农业大学苜蓿试验田土壤镰刀菌为研究对象,在前期土壤镰刀菌的分离、鉴定工作完成的基础上进行了致病性测定、接种不同致病性镰刀菌后苜蓿酶活性测定及不同作物上镰刀菌致病性测定等试验,为今后生防菌株的筛选提供依据。通过在品种德宝上的致病性测定一共得到16个强致病性菌株:其中茄病镰孢(F.solani)4个、尖孢镰孢(F.oxysporum)6个、砖红镰孢(F.lateritum)1个、黄色镰孢(F.culmorum)1个、半裸镰孢(F.semitectum)1个、雪腐镰孢(F.nivale)1个、拟丝孢镰孢(F.trichothecioides)2个;23个中等强度致病性菌株:茄病镰孢(F.solani)8个、尖孢镰孢(F.oxysporum)3个、砖红镰孢(F.lateritum)8个、木贼镰孢(F.equiseti)1个、三线镰孢(F.tricinctum)1个、潮湿镰孢(F.udum)1个、半裸镰孢(F.semitectum)1个。致病性测定共筛选出12个非致病性菌株:茄病镰孢(F.solani)4个、尖孢镰孢(F.oxysporum)4个、木贼镰孢(F.equiseti)2个、砖红镰孢(F.lateritum)1个、黄色镰孢(F.culmorum)1个、串珠镰孢(F.moniliforme)1个。接种致病性不同的镰刀菌后苜蓿酶活性的变化情况也不相同;通过试验发现各接种镰刀菌后超氧化物歧化酶(SOD)、过氧化物酶(POD)、多酚氧化酶(PPO)、苯丙氨酸解氨酶(PAL)酶活高峰接种后9d出现,而过氧化氢酶(CAT)酶活高峰在接种后6d到达。接种强致病性菌株的苜蓿酶活变化幅度远大于接种非致病性菌株的苜蓿。对在品种德宝上表现为非致病性的12个菌株和随机选取的10个致病性菌株在苜蓿品种德福、玉米、小麦、胡麻、小扁豆、萝卜6种作物上分别进行致病性测定,12个非致病性菌株中只有少数菌株在个别作物品种上表现出强致病性或中等强度致病性,如:茄病镰孢3号在小扁豆品种定选1号上表现强致病性;尖孢镰孢1在小扁豆品种定选1号、茄病镰孢3在胡麻品种陇亚七号上表现为中等强度的致病性,但多数菌株在供试作物品种上表现为弱致病性或非致病性,所以可以用于以后生防菌株的筛选研究。更多还原

【Abstract】 Fusarium root rot of Alfalfa, a kind of soil-brone disease, became more and more serious in the alfalfa-planting areas of Gansu, China. The Fusarium spp were obtained from the soil samples of alfalfa experiment field in campus of Gansu Agriculture University. Then the pathogenicity of Fusarium spp, enzyme activity after inoculation with different Fusarium and the pathogenicity of Fusarium isolates on different crops varieties were tested. So they can be used for biocontrol in the future.16 strong pathogenic isolates, 23 middle pathogenic isolates and 12no-pathogenic isolates were obtained. Strong pathogenic isolates were 4 strains of F.solani, 6 strains of F.oxysporium, 1 strains of F.culmorum, 1 strains of F.nivala,1 strains of F.lateritium, 1 strains of F.semitectium, 2 strains of F.trichothecioides; 23 middle pathogenic isolates were 8 strains of F.soalni, 3 strains of F.oxysporium, 8 strains of F.lateritium, 1 strains of F.equiseti, 1 strains of F.tricinctium, 1 strains of F.udum, 1 strains of F.semitectium; 12 no-pathogenic isolates were 4 strains of F.solani, 4 strains of F.oxysporium, 2 strains of F.equiseti, 1 strains of F.lateritium, 1 strains of F.culmorum, 1 strains of F.moniliforme.The activities of enzyme were different after inoculated with different Fusarium spp ; The results showed that variations of enzyme activities of POD,PPO,PAL,CAT and SOD were closely related to the pathogenicity of Fusarium spp after inoculation; The maximum value of CAT content was appeared after 6d inoculation, the maximum value of SOD, POD,PPO,PAL content was appeared after 9d inoculation. Moreover, the strong pathogenic strains value of enzyme content after inoculated were much higher than that of no-pathogenic strains.The 12 no-pathogenic isolates on Derby showed a little different pathogenicity on other 6 crops. a little part showed strong pathogenicity or middle pathogenicity.But most of them were the weak or no-pathogenicity.更多还原