摘要
[目的]应用15N自然丰度法研究盐胁迫条件下沙枣的生物固氮能力,并探讨几个耐盐树种的氮素分配情况。[方法]通过耐盐树种的室内砂培试验,确定盐渍生境条件下以空气氮为唯一氮源的沙枣15N相对丰度B值及其适宜的参比植物;估测室内和野外盐渍生境中沙枣的生物固氮能力;并通过测定碳、氮、磷元素含量探讨了几种耐盐树种的氮素分配情况。[结果]室内盐胁迫砂培试验条件下,沙枣的B值为-1.41‰;柽柳和白蜡可作为沙枣的参比植物;沙枣的生物固氮百分率为55.03%。野外中度盐渍环境中,沙枣生物固氮百分率为69.69%。试验条件下,沙枣、柽柳和白蜡3个耐盐树种中,沙枣植株及其叶、茎、根含氮量最高,且与其它树种差异显著(P<0.05);沙枣植株氮/碳含量比以及氮/磷含量比最高;沙枣叶、茎和根的氮/磷含量比最高。野外中度盐渍环境中,沙枣叶的氮/碳含量比以及氮/磷含量比均为最高。[结论]15N自然丰度法可用于研究盐胁迫条件下沙枣的生物固氮能力,柽柳和白蜡可作为参比植物;沙枣在盐胁迫下的固氮能力较强,是可应用于盐渍土生物改良的优良树种。本文为盐胁迫条件下利用15N自然丰度法研究生物固氮作用提供方法参考,对于盐碱地生物治理中植物材料的选择和耐盐树种资源的综合开发利用具有重要意义。
[Objective] To estimate the biological nitrogen fixation of Elaeagnus angustifolia under salt stress and to study the nitrogen distributions of several saline-tolerant trees species. [Method] Saline-tolerant trees were cultivated in greenhouse, and the value of ^15N natural abundance （B） and appropriate reference plants in saline habitat were determined; the biological nitrogen fixation abilities of E. angustifolia in greenhouse and field saline habitat were investigated; and the nitrogen distributions of several saline-tolerant trees were obtained by determination of carbon, nitrogen and phosphorus contents. [Result] The results of planting trials showed that the B value of E. angustifolia was -1.41‰; Tamarix chinensis or Fraxinus chinensis could be the reference plant of E. angustifolia; the biological nitrogen fixation percentage of E. angustifolia was 55.03%. The biological nitrogen fixation percentage of E. angustifolia in moderate salinity field was 69.69%. In the experimental condition, among three saline-tolerant tree species of E. angustifolia, T. chinensis and F. chinensis, E. angustifolia had the highest nitrogen contents in whole plants, roots, stems and leaves, and the contents were significantly different from other species （P〈0.05）; the nitrogen and carbon content ratio and the nitrogen and phosphorus content ratio of E. angustifolia were the highest; the nitrogen and phosphorus content ratios of leaf, stem and root of E. angustifolia were the highest. The nitrogen and carbon content ratio and the nitrogen and phosphorus content ratio of E. angustifolia leaves in moderate salinity field were the highest. [Conclusion] ^15N natural abundance method can be applied to the study of biological nitrogen fixation ability of E. angustifolia under salt stress, and T. chinensis and F. chinensis can be selected as the reference plants; E. angustifolia has relatively strong biological nitrogen fixation ability under salt stress, and it is an excellent tree species for biological improvement of salin
出处
《林业科学研究》
CSCD
北大核心
2017年第6期985-992,共8页
Forest Research
基金
国家自然科学基金青年科学基金(31400571)
国家“十三五”科技支撑计划项目“盐碱逆境高抗稳定植物种质优选技术与示范(2015BAD07B0102)”
中央级公益性科研院所基本科研业务费专项资金(CAFYBB2014QB052)
关键词
盐胁迫
沙枣
生物固氮
耐盐树种
salt stress
Elaeagnus angustifolia
biological nitrogen fixation
saline-tolerant trees
