Reglation Of Nitrogen Nutrition To Sucrose Metabolism In Sugar Beet (Beta Vulgaris L.) Roots

In this dissertation, Tianyan 7 of NZ sugar beet and Tianyan 8 sugar beet were selected as experimental sample, and experiments were made in the campus and practice base of NEAU from 2007 to 2008. Experimental factors were as follows: NO3--N,NH4+-N,CHM and pH. In experiments the L16(45) design was adopted. We studied on dynamic changes and regulation approaches of key enzymes and main products of nitrogen assimilation and sucrose metabolism with different treatments on Tianyan7 of sugar beet, the mechanism of nitrogen assimilation and sucrose metabolism, further analyzed interaction mechanism between nitrogen assimilation and sucrose metabolism, and announced the regulation effect of different treatments on Tianyan7 and Tianyan8 nitrogen assimilation, sucrose metabolism, yield and quality. This dissertation will fill in the infrastructure data of sugar beet physiology, provide theoretical basis for identifying, evaluating, reforming and using germplasm resources, and making reasonable cultivation measurement. Results of this experiment are as following:1.In the process of nitrogen assimilation, the ammonium and nitrate with different treatments on key enzymes have different effect. In this examination, on singleness NO3--N,NH4+-N treatment,NR activity and GS activity all enhanced with treatment.On singleness NO3--N treatment,with NO3--N level enhance,synthesis activity of SS in sugar beet roots was reduced and decomposition activity of SS was increased. On singleness NH4+—N treatment,with treatment level enhance,synthesis activity of SS in sugar beet roots was reduced and decomposition activity of SS in sugar beet roots was increased.2.Different treatment on NO3-/NH4+ ,have different effect for key enzyme nitrogen assimilation and sucrose metabolism of sugar beet. NR activity were gradually enhanced with increasing the concentration of NO3- and reduced with increasing the concentration of NH4+, and while NO3-/NH4+ on 4:1 was the best for activity of NR;activity of GS on sugar beet roots were gradually enhanced with increasing the concentration of NH4+ , and while NO3-/NH4+ on 1:4 was the best for activity of GS.Different treatment on NO3-/NH4+, SS synthesis activity was higher than that single nitrogen nutrition of SS synthesis activity, while NO3-/NH4+ on 3:1was best for SS synthesis activity, and effect on of sugar content rate was in the order: 3:1>1:1>1:3>4:1>1:4;NO3-/NH4+ on 4:1 was the best for decomposition activity of SS, and effect on of sugar content rate was in the order: 4:1>3:1>1:1>1:3>1:4。3.In different consistence of CHM treatment,NR activity in sugar beet leaves was reduce with CHM consistence enhanced.Activity of GS in sugar beet root was enhance when CHM increasing.pH have some effect to key enzyme nitrogen assimilation.pH on 7.0 is the best for activity of GS in sugar beet roots.Activity of SS synthesis and decomposition were enhance with CHM.but activity of SS decomposition was lower than activity of SS synthesis.The effect on pH for activity of SS synthesis was in the order: 7.5>7.0>6.5>6.0;and activity of SS decomposition was in the order: 7.0>7.5>6.5>6.0.4. Regulation to Tianyan 7 and Tianyan 8 in earthnut rise time and sugar accumulate time ,the result show that, different factor have different contribution rate to yield,the effect on root yield the four factors for Tianyan7 was in the order: NO3->CHM>pH>NH4+;for Tianyan8 was in order: NO3->NH4+>pH>CHM.Different treatment have different influence on sugar content rate for Tianyan7 and Tianyan8.The four factors on roots sugar content rate for Tianyan7 was in order: NO3->pH>NH4+>CHM;for Tianyan8 was in order: NO3-> pH> NH4+> CHM.Regulating substances had different influence on sugar yield of the same sugar beet variety, effects on on sugar yield was of Tianyan7 in the order: NO3-> CHM > pH> NH4+, for Tianyan8 was in order: NO3-> NH4+ > pH > CHM.