Using SSR Marker To Map The Mutant Sites Of The Wheat Salt-Tolerant Mutant And The Study On The Difference Of Its MtDNA

Salinization of soil is a severe problem that has negative effects on farm production and ecological environment. Much attention is paid to raising salt-tolerant plants, studying salt-tolerance mechanism, locating and isolating salt-tolerance genes. In this experiment, F2 population was used as the population of mapping genes. The F2 population was derived from the hybrids of wheat salt-tolerant mutant RH8706-49 and salt-sensitive mutant H8706-34 (both of them are derived from a single seed). The relative salt-tolerance gene of wheat salt-tolerant mutant was mapped by using microsatellite marker and BSA. Among the 246 pairs of microsatellite primers, there were 10 pairs had polymorphism between RH8706-49 and H8706-34 (the polymorphic index is 4.07%). When further verification was taken in the salt-tolerant pool and the salt-sensitive pool, only the PCR products of WMS299 showed difference in the two pools. After WMS299 was amplified in the F2 population, most of the salt-tolerant plants had the same band as that of RH 8706-49, and most of the salt-sensitive plants had the same band as that of H8706-34. This suggested that there be a linkage between microsatellite marker WMS299 and the mutant site which had been located on the 3BL. By mapping the gene with Joinmap 1.4 (software), the genetic distance between the site and WMS299 is 14.003cM. This result had established the fundament for isolating salt-tolerance genes from the experiment materials.In our lab, RH8706-49 and a salt-sensitive material had been chose as parent plants to be hybridized and anti-hybridized. The F1 of the two hybridized combinations had higher salt-tolerant index than the salt-sensitive parent's. FI of the combination that took RH8706-49 as female parent had higher salt-tolerant index than that of FI of the anti-hybridized combination. This indicated that the heredity of plants' salt-tolerance might be relevant to cytoplasmic genes. In the second part of the experiment, RH8706-49^ H8706-34 and their female parent Punong3665 were used as experimental materials, and RAPD was used to find the differences among their mtDNA. Out of the 53 random primers, there were 2 primers whose products had specific bands in RH8706-49. The specific bands of RH8706-49 were collected cloned and sequenced.