文献类型：期刊文献

中文题名：模拟氮沉降对低磷胁迫下马尾松无性系细根形态和氮磷效率的影响

英文题名：Effects of simulated nitrogen deposition on fine root morphology,nitrogen and phosphorus efficiency of Pinus massoniana clone under phosphorus deficiency

作者：宋平[1] 张蕊[1] 张一[2] 周志春[1] 丰忠平[3]

第一作者：宋平

机构：[1]中国林业科学研究院亚热带林业研究所,国家林业局马尾松工程技术研究中心,浙江省林木育种技术研究重点实验室,杭州311400;[2]西北农林科技大学林学院,陕西杨凌712100;[3]浙江省淳安县姥山林场,浙江淳安311700

年份：2016

卷号：40

期号：11

起止页码：1136-1144

中文期刊名：植物生态学报

外文期刊名：Chinese Journal of Plant Ecology

收录：CSTPCD;;Scopus;北大核心:【北大核心2014】；CSCD:【CSCD2015_2016】；

基金：“十二五”国家科技支撑计划项目(2012BAD01B02);国家自然科学基金(31370671);浙江省农业新品种选育重大科技专项(2012C129-08-12)

语种：中文

中文关键词：无性系;细根;氮沉降;低磷胁迫;马尾松

外文关键词：clone; fine root; nitrogen deposition; phosphorus deficiency; Pinus massoniana

分类号：S725

摘要：根系是植物吸收土壤营养的关键部位,不同径级根系的形态和功能差异不仅与植株自身的遗传因素有关,而且受到土壤中营养元素分布和水平的影响。在我国亚热带高氮沉降和酸性红壤磷匮乏及不均一的土壤环境下,研究林木不同径级根系对外界营养环境变化的响应有利于深入了解林木根系的觅养机制及规律。该文以马尾松(Pinus massoniana)无性系19-5(高磷效率)和21-3(低磷效率)为材料,在同质低磷和异质低磷两种盆栽处理下,设置3个氮水平(对照、中氮和高氮)的模拟氮沉降实验。结果表明:1)马尾松无性系苗木的生长受磷环境、氮水平和无性系三因素共同影响,模拟氮沉降显著促进了异质低磷下马尾松苗高和整株干物质量的增加,而在同质低磷下氮效应不显著;在异质低磷、高氮下,无性系19-5的苗高和整株干物质量分别是无性系21-3的1.1倍和1.6倍。2)马尾松各径级细根长度和表面积随径级增大而减小,模拟氮沉降促进了直径≤1.5mm的细根的增生发育,直径1.5–2.0 mm的细根和>2.0 mm的较粗根无明显变化;另外,直径≤1.5 mm的细根长度占总根长的比例保持在90.4%–92.8%范围内,受氮影响较小。3)模拟氮沉降显著提高了异质低磷下无性系19-5≤1.5 mm的细根长度和表面积,同时,其根系氮、磷吸收效率较对照分别高出93.3%和148.4%;无性系21-3的根系氮、磷吸收效率受氮影响较小;根系氮、磷利用效率均无显著变化。上述结果表明,≤1.5 mm的细根的增生发育和氮、磷吸收效率的提高可能是磷高效马尾松无性系应对高氮低磷环境的重要响应机制。
Aims In forest ecosystems with phosphorus（P） deficiency, the impact of atmospheric nitrogen（N） deposition on nutritional traits related to N and P uptake potentially affect plant growth and vegetation productivity. The objective of this study was to explore the effects of simulated N deposition on fine root morphological characteristics and effiency of N and P absorption in Pinus massoniana under under low P stress. Methods Two clones of P. massoniana seedling with different P efficiency（high P efficiency 19-5 vs. low P efficiency 21-3） were used. A two-year pot experiment was applyed with treatments of two P conditions,（i.e. homogeneous low P availability vs. heterogeneous low P availability） and three N deposition levels（0, 30 and 120 kg N·hm–2·a–1; i.e., N0, N30, or N120, respectively）. Important findings 1） The growth of P. massoniana seedling was interactively affected the three factors： simulated N deposition, P condition and genotypes. Simulated N deposition increased the seedling height and dry mass under heterogeneous P deficiency, but did not significantly affect those traits under homogeneous P deficiency. Under heterogeneous P deficiency and N120 treatment, the seedling height and dry mass of clone 19-5 were 1.1 times and 1.6 times higher than that of clone 21-3, respectively. 2） Fine root length and surface area decreased asroot diameter increased. N deposition significantly stimulated proliferation of fine root with diameter ≤1.5 mm, while roots with diameters ranged from 1.5 to 2.0 mm and over 2.0 mm were not influenced. The length of fine root ≤1.5 mm in diameter accounted for 90.4%–92.8% of the total root length and was not affected by N deposition. 3） Under the heterogeneous low P condition, clone 19-5 was found to respond to the simulated N deposition with increased root length and surface area in fine-root diameter class of ≤1.5 mm. Additionally, in compared with control, its N and P absorption efficiency were significantly enhanced 93.3% and 148.4%, respectively under N120 treatment. However, the N and P absorption efficiency of clone 21-3 was less affected by the simulated N deposition. The N and P use efficiency had no notable variation. Finally, we found that the proliferation of fine-root ≤1.5 mm in diameter and high N（P） absorption efficiency maybe the adaptive mechanisms of P. massoniana responding to atmospheric N deposition under P deficiency.