利用Ta_1不育基因进行抗小麦赤霉病的轮回选择育种

Recurrent selection breeding by using Tai sterile gene for resistance to scab in wheat:

选用浙麦1号等5个带有Ta_1不育基因的农艺亲本和苏麦3号等15个赤霉病抗源,组建成抗小麦赤霉病轮回选择的基础群体。在对其进行二次表型轮回选择后,通过抗扩展性的改进,群体病穗的感病小穗率降低了9.55％,R和MR抗性级个体的频率分别提高了15.3％和12.8％,同时原群体的株高水平逐步降低,并在一定程度上削弱了株高与抗性间的不良连锁关系。从群体中选择的优良单株育成了120个纯系,经抗性鉴定,获得了23份抗赤霉病品系,其中2个品系的抗性超过了苏麦3号。本文还提出了利用Ta_1不育基因进行抗小麦赤霉病轮回选择育种的程序和方法。

Five agronomical parents (Zhemai 1 and so on) with Ta_1sterile gene and 15 scab resistance parents (Sumai 3 and so on) were selected to establish the basic population of recurrent selection for wheat scab resistance. After 2 times of phenotype recurrent selection and an improvement of the resistance to colonization, the disease rate of the population decreased 9.55％, the frequencies of R and MR individual resistance were increased 15.3％ and 12.8％ respectively, which showed that the resistance levels of the population and the individual were all upgraded. The plant hieght of the original population lowered gradually, as well as the undesirable chain relationship between plant hieght and its resistance were weakende. 120 pure lines bred from the excellent lines through the population selection were got, and 2 lines out of the 20 had higher resistance than sumai 3. The process and the methods of recurrent selection breeding by using Ta_1 sterile gene for the resistance to scab in wheat are discussed in the paper.