配合施用NH_4^+-N和NO_3^--N对旱作水稻生长与水分利用效率的影响  

WATER UTILIZATION BY RICE GROWING IN AEROBIC SOIL SUPPLIED WITH DIFFERENT RATIO OF NH_4^+-N AND NO_3^--N

作　　者：钱晓晴[1] 沈其荣[1] 徐国华[1] 

机构地区：[1]南京农业大学资源与环境科学学院,南京210095

出　　处：《土壤学报》2003年第6期894-900,共7页Acta Pedologica Sinica

基　　金：国家自然科学基金项目 (3 0 0 70 446;3 9970 449)资助

摘　　要：水稻作物通常被认为是典型的喜铵作物 ,然而越来越多的报道认为混合供应NH+4 N和NO- 3 N更有利于作物生长和产量的形成 ,水稻也不例外。水稻旱作后 ,由于土壤中的无机氮大量以NO- 3 N形态存在 ,因而NO- 3 N已成为旱作水稻的重要氮源。本文采用普通湿润冲积新成土进行盆栽试验 ,旨在探讨不同氮素形态比例对旱作水稻生长、产量形成和水分生产效率的影响。结果表明 :覆盖旱作条件下 ,配合施用NH+4 N和NO- 3 N可以显著降低水稻一生的总需水量 ,改善旱作水稻抽穗后功能叶的光合生产能力 ,提高蒸腾水分的干物质和籽粒生产效率 ;NO- 3 N施用比例在 5 0 %时有利于旱作水稻形成最高的生物学产量和籽粒产量 ;NO- 3 N施用达到和超过这一比例则使成熟期水稻根系质量及根冠比下降。Rice (Oryza sativa L) had been traditionally recognized as the typical plant preferred NH + 4-N as its N source. But more and more reports have shown that plant growth and yield is superior on mixtures of NH + 4-N and NO - 3-N compared with provision of either nitrogen alone and only a few species actually perform well when NH + 4-N was provided as the only N source. NO - 3-N had become the important N source for rice crop cultivated in aerobic condition because of most the inorganic N in soil existed in this fom. To evaluate the effects of mixed nitrogen nutrition on growth and water use efficiency of rice cultivated in aerobic condition,a pot experiment was conducted under different rates of NH + 4-N and NO - 3-N application from 3-leaf stage to earring stage of the crop. The mixed nitrogen solution of NH + 4-N and NO - 3-N was carefully injected into Typicudi-Alluuvic Primosols in pot every other two days at the ratio of 100/0, 75/25,50/50,25/75 and 0/100. The amount of water irrigated everyday photosynthesis rate of functional leaves and yield of rice were measured and counted.The results showed that the total requirement of water by rice could be significantly reduced by proper application of NH + 4-N and NO - 3-N in aerobic cultivation. Meanwhile the photosynthesis of the functional leaves after earring was improved greatly and the dry matter and grain productive efficiency of water by transpiration was raised by utilization of NO - 3-N at a suitable ratio. The highest biomass production and maximum grain yield was obtained when 50% of nitrogen fertilizer as NO - 3-N was applied. Both root weight and ratio of root and shoot would be reduced when the proportion of NO - 3-N was ≥50%.

关 键 词：旱作水稻 生长 水分 利用效率 影响因素 

分 类 号：S511[农业科学—作物学]