The Exogenous Genes Responsible For Delay Senescence And Resistance To Fusariuam Head Blight In Wheat Cultivars

Wheat is one of the world’s most important food crops, wheat production have a lot of growth than in the past after years of efforts by the breeders, however, it was limited by genetic background, such as the diversification of the genetic background and variation. Currently, the wheat production suffered from the restrictions of the disease or self-factors, which become the main obstacle in wheat breeding technology. We can now clearly aware of the wheat wild relatives is a great resource that we can use. They grow in naturally harsh environment to experienced a variety of natural conditions resulted in owning a large number of aviabliable genes. These favorable genes were transferred into the wheat genome by distant hybridization, which can improve wheat resistance to adverse natural conditions and diseases, to achieve the purpose of improving the quality of wheat and wheat production. This experiment is divided into two parts, in the first part, we chose two stay-green wheat cultivars, Chuannongl2(CN12) and Chuannongl7(CN17), harboring the wheat-rye1BL/1RS translocated chromosome and MY11, the agronomical parent of both CN12and CN18, which was used as the control as material. By means of adding the paraquat, we investigated the content of MDA, the activity of SOD, CAT, APX and photosynthetic index during the whole senescence stage.forldentification of the physiological and biochemical basis of the exogenous chromosome of wheat resistance to reactive oxygen stress. In the second part, we identify the scab resistance of the new lines661,693,696and699, all of which selected from the cross of MY11and Yu25, Yu25comes fron the distant hybrization of wheat and Thinopyrum intermedium, through both the single flower Injecting and spores smearing methods.The results are shown as follow:1The results showed that693is ideal resistant source for both initial infection and spread,696and699are bad on resistance to initial infection, but moderately on pread,661is susceptible lines which is bad both on initial infection than spread resistance.2At the whole paraquat induced senescence stage, stay-green wheat cultivars CN12, CN17have a higher content of chlorophyll than that of MY11. 3At the whole paraquat induced senescence stage, stay-green wheat cultivars CN12, CN17have a higher activity of SOD, CAT, APX,which means maintained a high level of activity of SOD,CAT, APX to scavenge the excessive ROS.4Compared with MY11,stay-green wheat cultivars CN12,CN18not only decrease the content of H2O2, regarding as the promoting factor for senescence, to protect the photosynthetic apparatus in membrane5The analysis of chlorophyll fluorescence parameter showed stay-green wheat cultivars CN12, CN17have a better activity and integration of photosynthetic apparatus in thylakoid membrane, which exhibited the construction was maintained well during the whole senescence stage.Above all, by investigating the Wheat materials with exogenous chromosome, it showed that exogenous chromosome contributed to resistance to Fusarium head blight and paraquat induced senescence.