Nitrogen rhizodeposition by wheat under different tillage systems in a rainfed Vertisol

作者：Munoz Romero Veronica; Lopez Bellido Rafael J; Redondo Ramon; Lopez Bellido Luis

来源：Field Crops Research, 2013, 144: 148-153.

DOI：10.1016/j.fcr.2013.01.005

• No tillage
• Conventional tillage
• N-15 labelling
• Leaf feeding
• N recovery
• N enrichment

Roots and the nutrients that they deposit into the soil are a natural source of N for a current crop, or a subsequent crop in the case of rotations. Despite the importance of this process, there are few field studies of rhizodeposition due to methodological difficulties. A two-year field study was conducted on a typical Mediterranean rainfed Vertisol to determine the effects of the tillage system on N rhizodeposition in wheat (Triticum aestivum L.). The tillage treatments were no-tillage (NT) and conventional tillage (CT). Wheat plants were labelled in situ with N-15 using a leaf feeding method. The total amount of N that was deposited by the roots in the full soil profile (0-75 cm) over two years was an average of 93 kg ha(-1). The N derived from rhizodeposition (NdfR) represented 40% of the total N content and 82% of belowground N for the wheat plant. The NdfR was higher under NT only in the first layer of the soil (0-15 cm). Fifty percent of the NdfR in the soil profile was observed within the first 15 cm, increasing to 74% within the first 30 cm. The amount of NdfR can be important for understanding farming systems and improving their management, especially the application of fertilizers.

• 出版日期2013-3-20