Comparative Of Winter Wheat Cultivars In Injury Degree And Expression Analysis Of CBFs Under Cold Stress

Planting winter wheat in high-cold area,also called northward relocation of winter wheat,is one of the possible measure to improve the production efficiency of wheat. Winter wheat "Dongnongdongmai1" cultivated by Northeast Agricultural University in2007can safely overwinter in Heilongjiang Province, but its cold resistance mechanisms have not been fully revealed. Currently evaluation of hardiness in winter wheat mostly used field survey reviving rate, however, because of the climate impact of different years may not reflect the true breed hardiness. This requires to clear the real hardiness of winter wheat under severe temperature conditions, in this experiment,field planted winter wheats were retrieved in the lab to give continuous cooling treatment, recorded survival rate simultaneous determination of physiological indicators and the degree of plants’injury. CBF genes play important roles in stress transcription factor, screening to CBF genes differentially expressed in two varieties based on our previous expression profiling sequence in different winter wheat with cold resistance, analysis the expression of these CBF genes between winter wheat cultivars under different temperatures, clearly CBF gene family members play key roles at low temperatures. The experiment showed the following results:The results show that electrical conductivity of winter wheat was significantly negative correlated with survival rate,the correlation coefficient is-0.66;half of winter wheat plants dead when electrical conductivity of tillering node reaches70%or more;plants were sampled from early frozen field were given-12℃in laboratory,species survival difference was significant during6-9days;plants were sampled from field which was frozen after30days were given-20℃in laboratory,after6-8days were easy to distinguish cold resistance between varieties;plants were sampled from depth of frozen field were given-27℃in laboratory,after6-8hours were able to distinguish cold resistance between varirties of winter wheats.The injury dregree of cell nucleus can be clearly observed under agarose gel electrophoresis of DNA, Clarity of thestrips can be correspondenced with survival rate.10genes were picked from the CBF family to compare the difference of the expression of2winter wheat with different cold resistance. The results show that the10CBFs in this experience all raise up to max under frozen treatment at different times.And the cold resistance of Donongdongmai1is higer than Jimai22.Explains that a large expression of the CBFs in tillering node of winter wheat can improve the cold resistance through some special channels.But the expression of winter wheat wont’t continue,only raise up at special times. In which the expression of CBF Ⅲ d-D19, CBF IV b-D21, CBF Ⅳ d-B4, CBF IV a-2.2, CBF Ⅳ d-B9genes time up to20under freezing temperature in cold variety, of which genes worthy of further study.