小麦条锈病重要抗源京核8811品系抗性遗传机制

GENETIC MECHANISM OF RESISTANCE OF WHEAT RESOURCE LINE JINGHE 8811 TO PUCCINIA STRIIFORWS

采用常温(昼18℃/夜10℃)、高温(昼24℃/夜15℃)两种温度处理,系统分析京核8811抗条锈性遗传基础及抗性特点。结果表明,京核8811中至少含有1对不完全显性主效抗性基因和2对隐性微效抗性基因。主效基因对温度不敏感,显性纯合时控制0～0;,杂合体控制0;^+～2^+。微效基因高温诱导表达,显性纯合、杂合或隐性纯合均对主效基因的抗性表达有修饰作用,当与杂合状态的主效基因重组,抗性达到高抗或免疫水平,自身隐性纯合可提供0;^+～2^+的抗性。通过主效、微效基因的重组控制较强抗性和较宽抗性谱,反映出不同类型抗性谱互补的抗性基因重组产生的“基因的集团效应”。并就“基因的集团效应”的抗性特点及其在实现品种抗性持久化中的作用进行了探讨。

Genetic basis and characters of resistance of wheat line Jinghe 8811 to Puccirua stri-iformis were analyzed systematically by treated at normal (day 18℃/night 10℃) and high (day 24℃/night 15℃) temperature. The results showed that there were at least one incomplete dominant major gene and two recessive minor genes in this line. The major gene was insensitive to temperature, its dominant homozygote controlled 0 - 0; phenotypes and its heterozygote controlled 0; + - 2 + phenotypes, respectively. Expression of minor genes was induced by high temperature. Minor genes could modify expression of major gene no matter that minor genes were dominant homozygotes, het-erozygotes or recessive homozygotes. The high resistance or immunity to P. striiformis can be obtained in the line Jinghe 8811 when the major gene recombined with minor genes. 0; + - 2+ phenotypes can be controlled by recessive minor genes themselves. Thus, high resistance and wide resistance spectrum were obtained by recombination of major and minor genes in line Jinghe 8811. The results suggested that 'Group Effect of Genes (GEC) ' could be developed from recombination of the different genes with complementary resistance spectra. Characters of ' GEG' and its function on durability of resistance were discussed in detail.