Abstract
The comparative effects of partial root-zone irrigation (PRI) and deficit irrigation (DI) on phosphorus (P) uptake in tomato (Lycopersicon esculentum Mill.) plants were investigated in a split-root pot experiment. The results showed that PRI treatment improved water-use efficiency (WUE) compared to the DI treatment. PRI-treated plants accumulated significantly higher amounts of P in their shoots than DI plants under organic maize straw N fertilisation, whereas similar levels of shoot P accumulation were observed under mineral N fertilisation. Thus, the form of N fertiliser, and thereby the different plant N status, affected the accumulation of P in shoots, as reflected by a higher plant N:P ratio following mineral N fertilisation than after organic N fertilisation. Compared to the DI treatment, PRI significantly increased both the physiological and agronomic efficiencies of P-use under mineral N fertilisation, while similar physiological and agronomic P-use efficiencies were found between the two irrigation treatments with organic N fertilisation. PRI-induced drying and wetting processes might have influenced the bio-availability of soil P, as the concentrations of bio-available P in both bulk and rhizosphere soils were increased compared with the DI treatment under both forms of N fertilisation. It is suggested that a relatively high soil water content in the wet zone of the PRI treatment should be maintained in order to facilitate nutrient (i.e., N and P) transport from the bulk soil to the root surface, thereby enhancing nutrient uptake by the roots.
| Original language | English |
|---|---|
| Journal | Journal of Horticultural Science and Biotechnology |
| Volume | 87 |
| Issue number | 6 |
| Pages (from-to) | 600-604 |
| Number of pages | 5 |
| ISSN | 1462-0316 |
| Publication status | Published - Nov 2012 |
Keywords
- Irrigation
- Deficit irrigation
- Partial root-zone drying irrigation
- Phosphorus
- Nitrogen fertilisation
