供氮形态和水分胁迫对苗期水稻根、冠生长的影响

Effects of nitrogen forms and water stress on root and shoot growth of rice at seedling stage

采用营养液添加聚乙二醇(PEG6000)人为模拟水分胁迫的培养方法,在5种供氮形态(铵硝比为0/100、25/75、50/50、75/25、100/0)和两种水分条件(非水分胁迫与水分胁迫)下,研究了苗期水稻(Oryza sativa L.)根系形态和地上部生长动态.结果表明:不论是在非水分胁迫还是水分胁迫条件下,不同形态、比例的氮素对水稻株高、叶面积,根长、表面积、直径有显著影响.两种培养条件下,水稻均在 NH_4^+-N 和 NO_3^--N 混合营养时生长最好.正常水分条件下培养的水稻幼苗在 NH_4^+-N/NO_3^--N 为50/50时生长最好,而模拟水分胁迫培养的水稻则以25/75处理生长最好.

By using the method of nutrient solution culture and simulated water stress with PEG6000. We discuss the effects of coupling between different nitrogen forms（the ratio of NH4^＋ to NO3^- is 100：0,75：25,50：50,25：75,0： 100）and two water conditions on growing tendency and Root Morphometrics during young seedling of rice. The results showed that the rice plant height leaf area and root length surface area volume and fractal dimension respond to different ratios of NH4^＋ / NO3^- and water stress condition dramatically . The rice crop could grow better under a mixed provision of NH4^＋ - N and NO3^- - N than under single provision of either NH4^＋- Nor NO3^- - N both in nor mal and simulating water stress solution cultures. The best growth of rice seeding was found in the NH4^＋ - N/NO3 - N ratio of 50/50 in nor mal solution cultures while it was in the NH4^＋ - N/NO3^- - N ratio of 25/75 in simulating water stress solution cultures.