Wang, Huiqun3; Liu, Fulai3; Andersen, Mathias Neumann5; Jensen, Christian Richardt3
1 Department of Agroecology and Environment, Faculty of Agricultural Sciences, Aarhus University, Aarhus University2 Climate and Bioenergy, Faculty of Agricultural Sciences, Aarhus University, Aarhus University3 KU-LIFE4 Department of Agroecology - Climate and Water, Department of Agroecology, Science and Technology, Aarhus University5 Department of Agroecology - Climate and Water, Department of Agroecology, Science and Technology, Aarhus University
The effects of partial root-zone drying (PRD) as compared with deficit irrigation (DI) and full irrigation (FI) on nitrogen (N) uptake and partitioning in potato (Solanum tuberosum L.) were investigated. Potato plants were grown in split-root pots and were exposed to FI, PRD, and DI treatments at tuber bulking stage. Just before onset of the irrigation treatment, each plant received 0.6 g N (in the form of urea) with 5% of which was 15N-labeled. After 4 weeks of irrigation treatments (i.e., one drying/wetting cycles completed in the PRD treatment), the plants were harvested and plant dry mass and N content were determined. The results showed that although the plant dry mass was not affected by the irrigation treatments, due to a reduced water use by the plant, both the PRD and DI treatments significantly increased crop water use efficiency. Compared with the FI and DI plants, PRD plants had significantly higher N contents in the leaves, stems and tubers; whereas, the 15N content in the plant organs was similar for the FI, PRD, and DI plants. It is suggested that not the root N uptake efficiency but the soil N availability was enhanced by the PRD treatment.
Irrigation Science, 2009, Vol 27, Issue 6, p. 443-448