N、P、Mg肥对甜菜谷氨酰胺合成酶

In pool culture experiments the quadratic rotation-orthogonal combination design was adopted. Experimental factors were as follows: NO3--N, NH4+-N, MgO and P2O5. In paper the regulation of four experimental factors on the glutamine synthetase (GSA) of roots and leaves of sugar beet. Results of this experiment are as following: At seedling stage, the foliage formation initial stage, and the initial and the end stage of root growth every single factor were related significantly with the activity of GSA of roots, and in every stage of sugar beet there were significantly correlations between single factor and GSA of leaves. Increasing the amount of nitrogen or magnesium made GSA of boot at earlier stage increase and GSA of boots at later stage decrease; at the earlier stage increasing the amounts of NO3--N and magnesium made GSA of leaves be inhibited and higher amount NH4+-N improved GSA of leaves, and at the later stages increasing the amount of NO3--N was helpful to enhancing GSA of leaves and the higher amount of NH4+-N and magnesium would inhibit the increasing of GSA of leaves. At the root growth earlier stage the interactions of two factors were related significantly with GSA of roots and in the whole growth period there were significantly correlations between the interactions of two factors and SPSA of leaves. At the root growth earlier stage higher NO3--N and lower NH4+-N, or higher magnesium andlower NH4+-N made GSA of boots increase; and applying NO3--N and NH4+-N or NH4+-N and magnesium together all has a greater effect on the GSA of leaves. And the contributors of four factors on the GSA of roots and leaves at different growth and information stage were different. At same time we obtained the different treatment combinations at the highest activities of GS of sugar beet when the effects of four factors were outstanding.