Mo17抗玉米丝黑穗病的基因效应分析

在人工接种条件下研究了玉米丝黑穗病重要抗源Mo17在不同感病背景下的基因效应差异。两背景下不同世代间玉米抗丝黑穗病程度存在极显著差异，F1和F2的病株率介于双亲之间，偏向与抗病亲本，均无超亲优势，F1与双亲回交，后代的病株率基本偏向于回交亲本；玉米抗丝黑穗病的遗传分别符合六参数和四参数模型，其遗传贡献中主要以加性和显性效应为主，但在黄早四背景下表现为超显性且存在明显的上位效应，而3788背景下加性、显性效应相当，且仅存在加性、显性上位效应；以Mo17为抗病亲本组合的抗病性至少由1对抗性基因控制，估计的基因对数为0.48~1.03。

The gene effect analysis of Mo 17 resistant to maize head smut

The gene effect difference of maize variety Mo17 which is an important resistant germ plasm to maize head smut is studied in this experiment in various susceptible backgrounds on condition of manual inoculation. There is significant difference of resistance degree among generations. The susceptible ratio of F1 and F2 is between the two parents and inclines to the resistant one, and there is no heterobeltiosis among offspring. The susceptible descendant ratio is mostly inclined to the backcross parent when backcross is made between F1 and their parents. The inheritance of maize head smut is in accordance with six parameter model and four-parameter model, and the main genetic effects are additive effect and dominant effect. But there is evident epistatic effect and overdominance effect in the background of the maize variety Huangzao 4, and there is only additive effect and dominant effect in the maize variety 3788, which are almost equal. There is at least 1 pair of resistant gene in the cross of which one parent is Mo 17, and the calculation gene pair is 0.48~1.03.