不同氮吸收效率水稻品种蔗糖代谢酶的活性比较

Comparison on the Activity of Sucrose Metabolic Enzyme in Rice Variety with Different Nitrogen Absorption Efficiency

[目的]阐明氮素代谢效率的高低与蔗糖代谢强度的关系。[方法]以不同浓度的NH4NO3(0.1、0.5、2.5、12.5 mm/mol)对2个水稻品种桂单4号(GD)和南光(NG)进行水培处理,并对不同供氮水平下不同水稻品种的蔗糖代谢酶的活性进行了比较。[结果]GD叶片蔗糖磷酸合酶以及叶片和根中酸性转化酶活性高于NG,蔗糖含量和低氮水平下谷氨酰胺合成酶(GS)活性高于NG,而中性转化酶的活性在不同供氮水平下的两品种间差异不显著。在所有供氮水平下NG叶片和根中的硝酸还原酶(NR)活性均高于GD。[结论]GD的氮素代谢水平高与低氮水平下GS的活性、蔗糖的合成与分解活性较高有关,而与NR活性无关。

[Objective] The aim was to illustrate the relationship between the nitrogen metabolic efficiency and the sucrose metabolic intensity.[Method] Two rice（Oryza sativa L.） varieties of Guidan 4（GD） and Nanguang（NG） was made by hydroponic culture with different concentration of NH4NO3（0.1,0.5,2.5,12.5 mm/mol）,and the activity of sucrose metabolic enzyme in different rice cultivars was compared under various nitrogen supply levels.[Result] The sucrose phosphate synthase（SPS） in leaves and the acid invertase activities in leaves and roots of GD were higher than that of NG,the sucrose content and glutamine synthetase（GS） activity under low nitrogen supply level was higher than that of NG,but the difference of the neutral invertase activity between the two rice varieties under different nitrogen supply levels were not obvious.The activities of nitrate reductase（NR） in leaves and roots of NG under all nitrogen supply levels were higher than that of GD.[Conclusion] The high nitrogen metabolic level of GD was related to the GS activity,sucrose synthesis and higher degrading activity under the low nitrogen supply level,but it had no relation with NR activity.