| Agropyron, an important wild relative species to wheat, occur at three ploidy levels (i.e., 2n = 14, 2n = 28, and 2n = 42). Agropyron cristatum (2n=28, genomes PPPP) is the model species having many useful traits, such as tolerant to abiotic stresses caused by drought, low temperature and salinity, and biotic stresses arising from various pathogens and pests. Intergeneric hybrids of common wheat with tetraploid A. cristatum have been obtained. And 19 wheat- A. cristatum disomic addition lines were obtained. 19 wheat- A. cristatum disomic addition lines and their parents were used to study their morphology, resistance to leaf rust, SSR and EST-SSR molecular markers.1. By comparing morphological and agronomic traits, 19 disomic addition lines can be divided into nine groups. It was found that Fukuho is susceptible to leaf rust, but addition lines ofâ…¡-30-5,â…¡-1-3,â…¡-3-1,â…¡-9-3 andâ…¡-11-1 and Z559 are immune to leaf rust. The results indicated that the A.cristatum chromosomes of the five addition lines have resistant gene to leaf rust and are important materials to find useful resistant gene to leaf rust.2. When comparing the transferability of common wheat SSR and EST-SSR to A. cristatum, 89.0% of SSR markers and 89.5% of EST-SSR markers gives a useful amplification in Fukuho, and the primers of 42.3% of SSR markers and 73.5% of EST-SSR markers amplified clear products in Z559, which indicated that the EST-SSR markers had higher transferability to A.cristatum than SSR markers. At the same time, EST-SSR primers have the higher ratio of strong bands on PCR products compared with SSR primers, and the identical result was obtained when comparing the polymorphism among three common wheat cultivars. On the other hand, the result obtained by EST-SSR markers was similar to that by SSR markers among three A.cristatum accessions. The analysis showed that the EST-SSR markers and SSR markers explored from common wheat can be used to the research of A.cristatum, while the former is the better.3. In order to obtain SSR and EST-SSR molecular markers of A.cristatum, PCR amplification were done in ninteen wheat-A. cristatum disomic addition lines and their parents. And these addition lines were devided into two groups, the first group is thirteen addition lines, the second is six ones. Sixty two EST-SSR and SSR markers of A. cristatum chromosome-specific were obtained. By PCR analysis of 13 addition lines, nineteen markers were found, five molecular markers of those (i.e., marker ksum41208, ksum62148, cnl123240, swes160228 and Xgwm124126) can be used in detecting P chromosomes of addition lineâ…¡-21-2 andâ…¡-21-6. Six markers of those (such as, marker hafl18146, swes19220, swes22170, swes157205, swes143272 and Xgdm107316) are suitable to detect P chromosomes in addition lineâ…¡-4-2, 5038,â…¡-5-1 and 5043. Seven markers of those , swes90126, swes160228, swes220170, swes223132, swes236180, cfe37158 and Xgwm162182 ,can be used in detecting P chromosomes of addition lineâ…¡-30-5,â…¡-1-3,â…¡-3-1,â…¡-9-3 andâ…¡-11-1. Ksum154148 is the only marker for addition lineâ…¡-7-1 and cfe37158 is the only one for addition lineâ…¡-8-1. Furthermore, these markers obtained from tetraploid A. cristatum were suitable to detect P chromosomes of diploid and hexaploid A. cristatum.By PCR analysis to the other six wheat-A.cristatum disomic addition lines, 43 primers have amplification to the A.cristatum specific chromosome of wheat-A.cristatum addition lines, of which 29 primers have specific bands of A. cristatum in six addition lines, at the same time, most of them were the primers of the sixth homeologous groups of wheat, only a few were the primers of other homeologous groups of wheat. So it is concluded that the A. cristatum chromosomes of wheat-A.cristatum disomic addition lines have partial homeology with the sixth homeologous groups of wheat, and it may be rearranged with the other six homeologous groups chromosomes, and it is designed to 6P of wheat-A.cristatum addition lines. In addition, a simple genetic model map of the six addition lines was drawn; which are little different with P chromosomes of A. cristatum. As a result, 19 disomic addition lines can be divided into six groups based on molecular marker combined with their morphological characters.In summary, the SSR and EST-SSR molecular markers obtained in this research not only be able to detect the alien chromatin of A. cristatum of wheat-A.cristatum addition lines, but also can used on grouping the addition lines. Based on molecular markers and morphological traits, 19 disomic addition lines could be divided into six groups. The first group is addition lineâ…¡-21-2 andâ…¡-21-6; The second is addition lineâ…¡-4-2, 5038,â…¡-5-1 and 5043, the A. cristatum chromosomes of those may be the seventh homeologous group; The third is addition lineâ…¡-30-5,â…¡-1-3,â…¡-3-1,â…¡-9-3 andâ…¡-11-1, A.cristatum chromosomes of those have resistant gene to leaf rust, and were rearranged; The fourth is addition lineâ…¡-7-1; The fifth is addition lineâ…¡-8-1; The sixth is addition lineâ…¡-29-2ii, 5114, 5113,â…¡-26, 5106 and 4844-12, the A. cristatum chromosomes of those may be the sixth homeologous groups. Those results could be used on determination the homeologous groups of A.cristatum of wheat-A.cristatum addition lines, construction of the genetic maps of the A. cristatum chromosome and comparison of genomes of A. cristatum.
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