A mutation causing self‐fertility (SF) in perennial ryegrass was studied at the tetraploid level. The aim of this work was to determine a) whether SF remains functional in a tetraploid population and b) whether the SF mutation expresses dominance in heterozygous pollen grains. A tetraploidized plant carrying SF alleles was self‐pollinated to create a segregating F₂ population. In the F₂ individuals, pollen compatibility ranged between 38% and 84% showing that SF remained functional. The SF locus genotype was the main determinant of pollen compatibility explaining 78% of the variation. The observed segregation was significantly different from the expected under both SF being dominant or recessive models (P_(χ2)≤0.001) and tended to be intermediate between them, indicating partial dominance or additive gene action. The frequency of the different genotypes suggested that pollen grains homozygous for the mutation have a competitive advantage over heterozygous pollen and that pollen compatibility is affected by the interaction with additional loci. The implications of our results for breeding polyploid grasses are discussed.

中文翻译：

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四倍体多年生黑麦草（黑麦草）种群中自育基因的遗传模式

在四倍体水平上研究了多年生黑麦草中导致自育（SF）的突变。这项工作的目的是确定a）SF是否在四倍体种群中仍然保持功能，以及b）SF突变是否在杂合花粉粒中表达优势。带有SF等位基因的四倍体植物被自花授粉，形成了一个分离的F ₂种群。在F ₂个体中，花粉相容性在38％至84％之间，表明SF保持功能性。所述SF轨迹基因型花粉兼容性说明的变化的78％的主要决定因素。SF是显性模型或隐性模型，观察到的偏析与预期的显着不同（P _（χ2）≤0.001），并且倾向于介于两者之间，表示部分优势或加成基因作用。不同基因型的频率表明，纯合突变的花粉粒比杂合花粉具有竞争优势，并且花粉相容性受与其他基因座相互作用的影响。讨论了我们的结果对多倍体草育种的意义。