不同氮效率水稻苗期对氮素水平及水分胁迫的响应

Different Nitrogen Efficiency Rice Response to Nitrogen Levels and Water Stress at Seedling Stage

本试验利用两种不同氮效率杂交稻品种(氮高效品种德香4103和氮低效品种宜香3724),采用聚乙二醇(PEG-6000)模拟水分胁迫,比较分析不同氮素浓度(N0、N1、N2分别为0、2.5、5 mmol/L)和不同水分胁迫(P0、P1、P2分别为0、5%、10%)条件下,不同氮效率杂交稻苗期在生理指标和农艺性状上表现的差异。结果表明,在不施氮水平,各品种的生理指标、农艺性状明显低于施氮水平,且两品种的光合色素、可溶性糖、脯氨酸含量、氮积累量、苗高和茎粗随水分胁迫程度的增加呈递减趋势;在施氮水平,随水分胁迫程度的增加,德香4103的光合色素、可溶性糖含量(除N2水平下降低)增加,脯氨酸含量先减后增,苗高和茎粗降低,干物质和氮积累量在N1水平下降,N2水平先减后增;宜香3724的可溶性糖含量(除N1水平下降)增加,干物质和氮积累总量先减后增,其余均与德香4103表现一致。复水处理后,均表现为不同程度的升高或降低,即不同程度的补偿效应;且从水分胁迫处理到复水处理后,两品种表现出来的氮素总量积累与干物质积累量呈一定的正相关关系。由以上可以看出不同氮效率品种对不同水氮的反应不同,表现出不同程度的水氮协同作用,也得出N高效品种德香4103比N低效品种宜香3724有更强的适应氮、水胁迫的能力。

Polyethylene glycol（ PEG-6000） was used in this study to simulate water stress and comparatively analyze the differences in physiological index and agronomic traits of two different nitrogen use efficiency hybrid rice varieties（ N-efficient species De xiang4103 and N-inefficient species Yi xiang 3724） under the conditions of different nitrogen concentrations（ N0,N1,N2 respectively 0,2. 5,5 mmol / L） and different water stress（ P0,P1,P2,respectively 0,5 %,10 %） conditions at the seeding stage. The results showed that the physiological index and agronomic traits of all varieties in no nitrogen levels were significantly lower than that of nitrogen levels,and with the increase degree of water stress,the two species of photosynthetic pigments,soluble sugar,proline,nitrogen accumulation,seedling height and Seedling thickness showed a decreasing trend. Under the nitrogen fertilizer condition,with the increase degree of water stress,to De Xiang 4103,the content of photosynthetic pigment,soluble sugar increased（ In addition to N2 level decrease）,the proline content first decreased and then increased,seedling height and Seedling thickness decreased,the accumulation of dry matter and nitrogen decreased in N1 level and decreased at first and then increased in N2 level; to Yi xiang 3724,Soluble sugar increased（ In addition to N1 level decrease）,the accumulation of dry matter and nitrogen decreased at first and then increased,the remaining indicators behaved the same with De Xiang 4103. After rehabilitation treatment,the indicators showed different degrees of increased or decreased,that is the different compensation effects; and from the water stress treatment to after rehabilitation treatment,the accumulation of total nitrogen and dry matter are positively related to certain accumulation in two rice varieties. It can be seen that different nitrogen species showed different reactions to different water and nitrogen efficiency,and different degrees of synergistic effect of water and nitrogen. N-efficient species De xiang 4103 had stronger ability to adapt nitrogen and water stress than N-inefficient species Yi xiang 3724.