The Effet Of Drought Stress Influence In The Proline Metabolism Pathways Of Seedling Period Of Sugar Beet

Sugar beet is important sugar crops in the world. Drought has become the important factor restricting the development of its production and industry in the present production of sugar beet. Reducing sugar beet lack of moisture sensitivity and improving the drought resistance has become a problem urgently to be solved in sugar beet production. Deep digging drought-resistant related enzymes and genes of beet, and studying the drought-resistant mechanism of beet has the vital significance for sugar beet breeding. Under drought stress, the beet will synthesize osmotic regulation substances in a short time to adapt to drought conditions. In all of the osmotic regulation substances, proline is the most widely distributed. This paper selected three different kinds of drought resistance of sugar beet W6-1, CL-6, DY-5, simulating drought treatment for the 2 and 3 true leaf seedling. From the point of view of physiological indexes and molecular biology, this experiments measure the content change of the proline, the content change of proline metabolism related enzymes and genes, and explore the effect of drought stress influence in the proline metabolic pathways of seedling period of sugar beet. The following research results have been achieved:1. Using 15% PEG6000 simulate drought dealing with the sugar beet seedlings under different drought treatment time, mearsuring the content change of the proline, the content change of proline metabolism related enzymes and genes of all the processing samples(a total of 30 samples). The results show that the different materials、different growth periods of the accumulation of proline and the enzyme activity of P5 CR and P5 CS has the time dependence relationship with drought stress.They have positive correlation. There are significant differences between various materials, the proline content of strong drought resistance varieties are higher than that of drought sensitive cultivars in the same period.2. From the points of view of physiological indexes, analyzing correlation of proline content and the content change of proline metabolism related enzymes of the different types of sugar beet varieties of young leaf under drought stress. The results show that as the extension of stress time the accumulation of proline has positive correlation with the P5 CR enzyme activity and P5 CS enzyme activity. P5 CR enzyme and P5 CS enzyme is the key enzyme of proline accumulation, including P5 CS enzyme are the speed limit of proline synthesis enzyme.3. Using q RT-PCR technology analyzing 30 samples of different processing(including control) to test the expression quantity changes of proline metabolismrelated enzyme. Results show that the delta-OAT gene expression has no obvious changes, P5 CR gene and P5 CS gene expression are raised, Pro DH gene expression is declined. It explains that as the extension of stress time the accumulation of proline are realized by activating the synthesis of metabolic pathways.4. Comprehensivly analyzing the effect of drought stress influence in the proline metabolic pathways of seedling period of sugar beet of drought stress on sugar beet seedlings proline metabolic pathways. Results show as the extension of stress time, the accumulation of proline is by activating predominantly P5 CR enzyme and P5 CS enzyme proline synthesis metabolic pathways and Pro DH enzyme inhibition of proline catabolism pathway.The P5 CR enzyme、P5CS enzyme and Pro DH enzyme is a key enzyme of proline accumulation and the P5 CS enzyme is the most relevant enzyme of proline synthesis.