抗白粉病普通小麦-簇毛麦新种质的遗传学及生化鉴定

Genetic and Biochemical Identification of Common Wheat-Haynaldia villosa New Germplasms

普通小麦-簇毛麦抗白粉病新种质94G22-1和94-G33-1都对白粉病免疫。其体细胞染色体数为42,花粉母细胞减数分裂中期Ⅰ染色体构型为21个二价体。用感病小麦品种对其测交,F_1代全部对白粉病表现免疫,F_1代花粉母细胞减数分裂中期Ⅰ染色体构型为20个二价体加2个单价体。测交F_2抗感比符合3:1的预期分离比例。体细胞快速荧光原位杂交表明94G22-1、94G33-1都带有两条簇毛麦染色体;染色体C-分带证明这两条簇毛麦染色体是一对6V;重双端体分析确认6V代换的普通小麦染色体是6D。在谷草转氨酶(GOT)同工酶电泳图潜的GOT-2活性区,94G22-1、94G33-1显示了3条酶带,其中1条来自簇毛麦,由6V上的基因编码,亚基组成分析亦确证94G22-1、94G33-1是6D(6V)异代换系。

Both 94G22-1 and 94G33-1 with the somatic chromosome number of 42 are immune to powdery mildew in resistence test. Twenty one bivalents were observed at metaphase I(M I) in pollen mother cells(PMCs)of 94G22-1 and 94G33-1. When they were crossed with wheat cultivars susceptible to powdery mildew, the F1 plants were all immune to powdery mildew. Twenty bivalents and two univalents were observed at MI in their PMCs. The ratio of the number of plants immune to susceptible to powdery mildew in F2 population fitted to 3:1. Two chromosomes from Haynaldia villosa in 94G22-1 and 94G33-1 were showed by rapid fluorescence in situ hybridization. The two chromosomes were identified as chromosome 6 V by chromosome C-banding. It was confirmed by double ditelo-centric (DDT) analysis that the 6 V substituted for common wheat chromosome 6 D. Three isozyme bands with one coming from H. v, coded by a gene on chromosome 6 V were showed in 94G22-1, 94G33-1 by isozyme analysis of glutamate oxaloacetate transaminase(GOT). It was reassured by GOT-2 subunit analysis that 94G22-1, 94G33-1 were 6 D(6 V)substitution lines.