The Studies On Parthenogenesis And Fertility Regulation Of Photo-thermo-sensitive Genic Male Sterile Wheat

The studies on photo-thermo-sensitive genic male sterile wheat and two-line hybrid wheat breeding in China are the most advanced in the world. However, the male sterility of photo-thermo-sensitive genic male sterile wheat is not stable in hybrid seed production, and usually the purity of hybrid seeds is not high enough for hybrid wheat production. In this study, photo-thermo-sensitive genic male sterile wheat was induced to create parthenogenesis and adjust its male fertility, and the hybrid seeds were produced by means of plastic mulching technology. Major results are described below:1. Three kinds of reagents, selected from ten kinds of reagents, which had better effect on inducing parthenogenetic seeds in Funan, respectively were 2,4-D( 100mg/kg), KT( 100mg/kg) + Inositol(50mg/kg) + 2,4-D(50mg/kg) + DMSO(2%) and NAA(400mg/kg). The frequency of ovary expanding respectively was 69.26%, 69.23%, and 74.41%, and the frequency of seed setting was 0.45%, 1.67%, and 0.63% respectively.2. 8,836 emasculated florets were treated by reagent A(2,4-D) and reagent B(KT + Inositol+ 2,4-D+ NAA+ 6-BA+ DMSO), and 7409 ovaries expanded, 62 parthenogenetic seeds set in Beijing. The frequency of ovary expanding was 88.54%, and the frequency of seed setting was 0.71%. It suggested that the mean effect of reagent A and reagent B in Beijing was in accordance with that in Funan.3. Parthenogenesis progeny of F1 (BS20/ Yanzhan4110) and F1 (BS366/Guan35) were identified by SSR. The SSR results showed that Pal (3) from F1(BS20/Yanzhan4110) was not parthenogenesis progeny, and others were true.4. 2,4-D, 6-BA, ABA, Proline, CoCl₂ and Polyamine could be used to increase the fertility of male sterile lines, which increased the fertility of BS366 and BS400 in this study. ABT, CaCl₂, Ethephon and MH decreased the fertility of BS366 and BS400, especially the ethephon, which decreased the fertility of BS366 and BS400 to 0.5. In this study, the heading stage and flowering stage of BS366 covered by plastic wereboth three days earlier than CK, the sterility was 98.9%, and the sterile spikes accounted for 82.7% of the total. The results laid the groundwork for the new techniques for two-line hybrid wheat seed production.