SSR Marker Loading And RAPD Analysis Related To The Maize Male Sterility Gene Obtained By Space Flight

It is an important method of obtaining heterosis by using maize male sterility. The maize cytoplasm male sterile materials are infected easily by Bipolaris maydis race T toxin, so recently the search of maize male sterility was transferred from cytoplasm male sterile materials to nuclear male sterility materials. We sent maize seeds for satellite abroad in 1996 and got a nuclear male sterile mutant in the offspring of the single hybrid-chuan Dan No. 9. In order to analysis this material, the population RP³195(A) x S₃₇ was detected with Simple Sequence Repeat molecular marker and Random Amplified Polymorphic DNA, Products from PCR reaction were resolved by electrophoresis in 3% and 1.5% agrose gel containing ethidium bromide.The main results concluded as follows.1. Sterility investigation in fields showed that the population I (138 plants) were segregated in sterility. 33 among them were totally sterile and 105 were totally fertile. Aptness examination showed that xc² =0.0387, which was smaller than x²_0.01,1=6.63. While the population â…¡ (247 plants), among which 71 were totally sterile and 176 were totally fertile. Aptness examination showed that xc² =0.304, which was less than x²_0.01,1 =6.63. Thus the two populations with different spikes both conformed to the segregation law of 3:1, which showed that the sterile character was controlled by a pair of recessive gene.2. Maize GMS gene was located with SSR molecular marker and campestral sterility analyzing. Among the 326 pairs of microsatellite primers selected, 56 were found polymorphic. Linkage analysis of F2 populations with the 56 pairs of primers showed that microsatellite markers bnlg197 and umc1012 were linked to the male sterility gene. The genetic distance between marker bnlg197and the male sterility gene in the two different F₂ populations was 7cM and 14.5cM respectively. The genetic distance between primer umc1012 and the male sterility gene was 28.5cM. Therefore the male sterility gene was located on 3L.3. Bulked segregation analysis (BSA) strategy was employed to identify random amplified polymorphic DNA (RAPD) marker linked to the maize male sterility gene a totalof 152 random 10-mer oligonucleotide primers were screened on the DNA of fertile and sterile bulks. Primer SBSK-14(CCCGCTACAC) and SBSR-3(ACACAGAGGG) give repeatable polymorphism between the two bulks. Through the linkage analyzing of the each plant of F2 segregation populations, the results indicated that the RAPD makers, SBSK-1485(^ SBSK-H475 and SBSR-3400 were linked to the maize male sterility gene, and genetic distance of 49.6cM> 26.6cM and 31.7cM respectively.