Comparison Of Some Physiological Traits In Over-wintering Stage And Genes Expression In Sugar Metabolism In Winter Wheat

Heilongjiang province is located in the northern cold area and the winter temperature is very low,so cold hardiness level become one of the main breeding objectives in the breeding process of winter wheat.Now the researchers have studied in many fields about hardiness of winter wheat in the morphology,cytology, physiological and biochemical indexes and molecular biology research and so on, they find hardiness of winter wheat is because of their physiological characteristics, genetic factors, and the external environment result of combined action. Winter wheat varieties can overwintering is less in the northern cold area. On the one hand, instructions for production application of winter varieties of safe choice is limited, on the other hand also suggests that to foster a breakthrough progress in overwinter is quite difficulty.With the rapidly development of molecular biology theory and technology, the mechanism of the winter wheat hardiness has further deepening the researches and acquired a lot of cold hardiness genes,but we can’t clear these genes is winter wheat hardiness improve main factors. The experiment is to cold hardiness differences of4winter wheat varieties as the research material by the way of field planting,winter wheat samplings from cold acclimation and freezing in winter that comparison between different hardiness winter wheat varieties (lines) and different period the change of osmotic regulation substances in the leaf.At thesame timealsotocold resistancevarieties DONGNONGDONGMAI1and cold sensitive varieties wheat JIMAI22as the research material by the way of indoor low temperature incubator plant,winter wheat samplings from the cold acclimation (CK),,4℃6h,4℃40d、-10℃、-12℃、-14℃、-168、-18℃2h8sampling period for testing different cold hardiness of winter wheat under low temperature stress of sucrose metabolism enzyme gene expression differences.For cold area provide theoretical basis to wheat genetic basis and genetic improvement potential.This study concluded that:1. Winter wheat tillering the water content of all varieties (lines) all showed a downward trend in during the winter, the stronger the cold hardiness of varieties (lines), the slower the decrease of water content; MDA content showed a trend of increasing, frozen period after the end of each testing varieties of MDA content for cold resistance varieties MDA content is the lowest, cold sensitive varieties MDA content is higher; During cold acclimation cold sensitive varieties proline content increased significantly, and increase the size of the content were higher than cold hardiness varieties in the end of the cold acclimation, testing varieties similar change trend of proline in the freezing proline content difference was not significant, therefore proline is not as cold hardiness index of winter wheat freeze; Soluble protein in cold acclimation during which there is no obvious difference, after entering freezing a significant difference between. Cold sensitive variety trend of the content of soluble protein decreased obviously, and the cold resistance of varieties increase the content of soluble protein smoothly and keep the high content of soluble protein can be used as evaluation index of varieties of hardiness strength; Cold resistance varieties (lines) soluble sugar in the overwintering period shows the trend to increase, cold sensitive varieties (lines) of change is steady, starch content during the overwintering period of decline, but cold resistance varieties decreased slowly.2.Associated with cold resistance of8physiological indexes related analysis, the correlation coefficient of main cold resistance index of cold acclimation period> over-wintering stage> freezing, winter wheat physiological and biochemical changes of cold acclimation period is the key to the winter of the winter wheat in cold area, the stronger the cold resistance of varieties (orlines) after freeze cold resistance related physiological indicators (MDA, soluble protein, soluble sugar, fructose and sucrose) stability is better than not cold resistance varieties.3.4related to sucrose metabolism enzyme genes expression, strong cold resistance varieties were higher than that of cold hardiness of weak varieties, in4℃treatment under the condition of strong cold resistance varieties of TaSS(sucrose metabolism enzyme gene) expression of the quantity increased, with4℃treatment40d to the maximum,-10℃treatment2h TaSS gene expression after falling rapidly, with the low temperature processing deepening the degree of cold hardiness of winter wheat varieties with different TaSS overall showed a rising trend,-18℃treatment2h after expressing quantity no difference; Different cold hardiness of winter wheat varieties TaFBA (fructose1,6diphosphate aldolase gene) in4℃cold acclimation period expression gradually rise,4℃treatment40d express maximum amount, following a downward trend; Different cold hardiness of winter wheat varieties TaSPS (sucrose phosphate metabolic enzyme gene) and TaADPG focal phosphorylase gene (glucose) in4℃domestication period showed a rising trend, to-10℃treatment2h TaSPS and TaADPG expression decreased, along with the temperature falling, after expressing quantity continues to rise, anti-cold variety TaSPS and TaADPG in-18℃treatment2h maximum. TaSPS in cold sensitive varieties-16℃treatment2h to handle, TaADPG maximum under-18℃.4sucrose metabolism related genes expression quantity differences are the biggest TaSPS in handle-18℃treatment2h, differences are the smallest TaSPS in-18℃treatment2h processing.