| In this paper, the genetic diversity of Roegneria kamoji was studied with gliadin and SSR analyse. And the genetic regularity and molecular marker of the resistant gene of the goatgrass from CIMMYT was researched, the results showed as fallows:1) The genetic diversity of 97 germplasm of Roegneria kamoji in Qingyijiang River and Mingjiang River Valley involved in 7 populations was analysed by gliadin A-PAGE. The result shows: (1) A total of 27 gliadin bands are separated by electrophoresis, of 26 showing polymorphism , which amounts to 96.3 %; and there are 86 different gliadin patterns in the 97 germplasms, which 77 gliadin pattern are unique; (2) The total genetic diversity index is 0.3451,and that of Qingyijiang River valley(0.3400) is higher than Mingjiang River valley's(0.3100),indicated that material of Qingyijiang River valley possess higher variance and genetic diversity; (3)There are abundant variation among populations within valleys. In Qingyijiang River valley, populations can be clustered significantly except Emei population, Menshan population is the most abundant of genetic diversity(0.3398) and the Hongyis the least(0.0947); In Mingjiang River valley, materials can be clustered based on upriver, middle reach and downriver, the upriver population posses greatest genetic diversity(0.3017),the downriver population is the least (0.1317);Based on genetic diversity of all the populations, the result indicated that the genetic diversity level is higher in vertical distributed area than those in horizontal area, and in Mingjiang River valley, because of fragmental habitat, the genetic diversity level of sub-populations is increased, and the genetic diversity level of total valley is decreased.2) The genetic diversity and genetic structure of seven natural population of Roegneria kamoji in Sichuan basin was investigated by SSR-PCR analyses. The result indicates that the genetic variation level of Roegneria kamoji is relatively high, the total genetic diversity is up to 0.3428. There is also upper genetic differentiation among populations, the coefficient of gene differentiation among population is 35.17%. Among all populations, Mengshan and Emei mountain population is the highest ones in diversity. The diversity of population is closely related with their distribution, which is to say, (1) the germplasms' genetic diversity of neighbor populations is nearly; (2) the population genetic diversity is decreased from west to east; (3) the genetic diversity level of vertical distributed populations is higher than those of horizontal distributed. This experiment makes it clear that SSR primers developed in goatgrass could be used for genetic diversity study on Roegneria komoji.3) Based on the study on the genetic diversity of Roegneria kamoji, the author make an advice for collection and conservation of Roegneria kamoji germplasm resources, i.e., establish natural conservation area in higher genetic diversity level area, such as Menshan mountain area and Emeishan mountain area; at the same time, collect the accession from the habitat fragmentation trifle plant multi-sitely and transplant to the natural conservation area.4) The genetic regularity of twelve goatgrass parents, which come from CIMMYT, resistant to stripe rust physiological strain CYR 32 was surveyed by analyzing Fi, and F2 populations from the crosses of them with the susceptible parent CD459. At the same time, cross combination of resistance multiply resistance was established to analyze resistance genetic regularity. The results shows in resistance multiply susceptible cross combination, plants are all resistant or immunity to CRY32 in Fi population, shows that the resistance of twelve elite parents is completely dominant, and in F2 populations, segregation ratio of resistance plants and susceptible plants was 3:1, indicated that their resistance to stripe rust is controlled by one dominant gene. Allelism analyse of resistance gene indicated that the resistance gene among resistance accession seems to be the same one dominant gene.5) Based on resistance identification and genetic analyse, the goatgrass accessionSQ-214 schlep a dominant gene resistance to stripe rust. Using SSRs molecular and group analyse in F2 segregate colony, this resistant gene is located on 7D chromosome, and linked with xgwm437 which genetic distance is 12 cM. And in F2 progeny, SSR primer WMC94 spread special band only in immune—neraly immune individual which is not produced in the parent individuals. Maybe it could be a useful tool of molecular marker in assistant breeding.
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