Molecular Cytogenetics Identification Of Wheat-Thinopurum Ponticum Hybrid Progenies

Thinopurum ponticum is one of the wild herds in Thinoprum, Triticum Aestivum which has widely adaptability and resistance. Thinopurum ponticum is immune to many kinds of diseases and insect pests, and has lots of superior characters such as high content of protein, high seed setting rate, it can be easily hybridized with wheat, so Thinopurum ponticum has became one of the most important species in Thinoprum used for wheat genetic improvement. It has great significance to introduce superior genes in Thinopurum ponticum into wheat and create valuable germplasm resources for breeding for wheat breeding by means of distant hybridization and chromosome engineering. This study identified 5 wheat-Thinopurum ponticum hybridized materials by morphology, micro-morphology, cytology and molecular biology. The purpose of this study is to select germplasm resources like addition lines, substitution lines or translocation lines which can be used for genetic study and wheat variety improvement. The main results are showed as following:⒈The characters of SNTE2007004 and SNTE2007005 was far from stablity by morphology test. SNTE2007004 and SNTE 2007005 need further selection.⒉The comparison of characteristics of pollen and leaf surface bwteen partents and hybrid progenies showed that the hybrid progenies inherited some characteristics of their partents.⒊Disease resistance test showed that all the five progenies were resistant to powdery mildew disease to some degree.⒋Cytology test revealed: In the SNTE2007001 strains,the number of chromosomes in most plant root tips was 40～42, they need further indetification. A few genetic stable individual plant had been selected,some individual plant was 42. PMCMⅠchromosome configuration in most individual plant was 2n=20～21Ⅱ, there were multivalents and low frequency of monovalent in some cells. Chromosome bridges were observed in the metaphase plate. There maybe substitution or translacation in SNTE2007001. The number of other progenies'chromsomes distributed from 40～44 which means gentic unstablity of them.⒌The results of RAPD was the hybrid progenies appears specific bands which was the same in Thinopurum ponticum but can't be found in common wheat by primers S22, S1146 and S1147. The bands can be used as special molecular marker of Thinopurum ponticum.⒍From the four test methods all the hybrid progenies contains the hereditary substance of Thinopurum ponticum, but there were only some individual plants achieved genetic stability and need furter indentification. Character segregation and genetic unstablity were still common in the other plants.