44份玉米自交系对镰孢穗腐病的抗性鉴定

Evaluation of Resistance to Fusarium Ear Rot in 44 Maize Inbred Lines

在2016年和2017年分别对44份不同来源的在自然发病条件下对穗腐病表现为抗病或感病的玉米自交系,分别人工接种拟轮枝镰孢和禾谷镰孢,对其抗性进行了鉴定。结果表明,塘四平头群的自交系发病最重,旅大红骨群的自交系发病最轻,瑞德群的自交系之间抗性差异较大。玉米自交系吉V203、承351和丹598对拟轮枝镰孢和禾谷镰孢均表现为高抗,而PHTD5和掖81162对两种致病菌均表现为高感。44份自交系在不同年份的抗性评级存在一定的差异,说明玉米穗腐病的发病受环境因素影响较大,也在一定程度上说明玉米穗腐病抗性遗传的复杂性。高抗和高感的玉米自交系在不同年份发病稳定,而中等抗性水平的自交系在不同年份的发病程度存在差异,受环境因素影响较大。本研究结果将为玉米穗腐病的抗性遗传改良提供一定的参考依据。

Forty-four maize inbred lines,which were from different heterotic groups with known levels of ear rot resistance,were tested for resistance to ear rot by artificial inoculation using Fusarium verticilloides or Fusarium graminearum in 2016 and 2017.As observed,those inbreds lines from Tangsipingtou group showed overall susceptible,while those inbred lines from Lvdahonggu group showed overall resistant to ear rot.Within the Raid group,different inbred lines represented the variation of resistance.The inbred lines Ji V203,Cheng 351 and Dan 598 showed simultaneously highly resistant against infections of Fusarium verticilloides and Fusarium graminearum,while PHTD5 and Ye81162 were highly susceptible.We also observed the differences on levels of resistance of 44 inbred lines in two calendar years,suggesting that the incidence of corn ear rot was greatly affected by environmental factors.That also provided an explanation on the complexity of resistance to ear rot.Notably,the resistant phenotype in highly-resistant and highly-susceptible inbred lines were reproducible over years,while inbred lines with moderate resistance were largely influenced,likely associated to the environmental factors.Taken together,these results provided insight in genetic improvement of resistance to ear rot in maize.