Artificial macropores attract crop roots and enhance plant productivity on compacted soils
Artificial macropores attract crop roots and enhance plant productivity on compacted soils
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DOI：
10.1016/j.scitotenv.2016.07.194
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发表时间：
2017-01-01
影响因子：
9.8
通讯作者：
Walter, Achim
中科院分区：
文献类型：
--
作者：
Colombi, Tino;Braun, Serge;Walter, Achim
压实土壤的结构特点是孔隙度（宏观）降低，从而导致机械阻抗增加和流体输送速率降低，从而降低根系生长和作物产量。特别是在高机械阻抗的土壤中，大孔可以作为根的最小阻力通道。本研究探讨了不同土壤物理状态与植物整体生长的关系，以及根系是否向土壤物理条件有利的点生长。试验在对照和田间条件下进行。大豆（Glycine max L.）、小麦（Triticum aestivum L.）和玉米（Zea mays L.）分别在未夯实土、夯实土和人工大孔夯实土上生长。利用x射线计算机断层扫描定量分析了根与人工大孔之间的相互作用。3种植物的根均向人工大孔生长。根要么长成大孔（主要在玉米中），要么与大孔杂交（主要在小麦中）。在压实土壤中人工大孔的存在使这三个物种在后期发育阶段补偿了早期活力的下降。这些结果表明，根系感知其物理环境，使它们能够向土壤条件有利的地点生长。不同类型的根-大孔相互作用表明，大孔是一种阻力最小的途径和氧气的来源，两者都能提高作物在压实土壤上的生产力。(C) 2016 Elsevier B.V.版权所有
The structure of compacted soils is characterised by decreased (macro-)porosity, which leads to increased mechanical impedance and decreased fluid transport rates, resulting in reduced root growth and crop productivity. Particularly in soils with high mechanical impedance, macropores can be used by roots as pathways of least resistance. This study investigated how different soil physical states relate to whole plant growth and whether roots grow towards spots with favourable soil physical conditions. Experiments were conducted under controlled and field conditions. Soybean (Glycine max L.), wheat (Triticum aestivum L.) and maize (Zea mays L.) were grown on uncompacted soil, compacted soil and compacted soil with artificial macropores. The interactions between roots and artificial macropores were quantified using X-ray computed tomography. Active growth of roots towards artificial macropores was observed for all three species. Roots grew either into macropores (predominantly in maize) or crossed them (predominantly in wheat). The presence of artificial macropores in compacted soil enabled all three species to compensate for decreased early vigour at later developmental stages. These results show that roots sense their physical environment, enabling them to grow towards spots with favourable soil conditions. The different kinds of root-macropore interaction indicated that macropores serve as a path of least resistance and a source of oxygen, both resulting in increased crop productivity on compacted soils. (C) 2016 Elsevier B.V. All rights reserved.