Alternative Irrigation Waters: Uptake of Mineral Nutrients by Wheat Plants Responding to Sea Water Application

Abstract

The growth and the uptake of mineral nutrients were investigated in seedlings of wheat cv. Ofanto grown in Hoagland's no. 2 solution, added with increasing sea water concentrations (0% for control, 10 and 20% for treatments). It was pointed out an increase of fresh and dry matter of wheat treated for 14 days with 10% sea water compared to the control, while a reduction was observed in wheat treated for 21 days and for the treatment with 20% sea water solution. Moreover, the sea water application reduced the elongation, affecting more shoots than roots. Under sea water irrigation uptake and translocation of mineral nutrients changed drastically. In particular, with growing a decrease of Cl⁻ in shoots and an increase in roots were noted in both the treatments. The high presence of Mg⁺⁺ in sea water affected considerably the plant nutritional requirement, influencing the uptake of Ca⁺⁺, which was restricted for competition, and the accumulation of P and Mn, which were instead enhanced. The general trend for micronutrient acquisition was an increase in both shoots and roots, except for the iron content, which decreased at the highest level of sea water. All the results obtained suggest the possibility of using sea water for alternative irrigation, adopting adequate dilutions for tolerant plants. This prospect could therefore have a fundamental role in the economy of natural basins in numerous Mediterranean regions, where the dry weather problem has a particular importance.

Keywords:

• Mineral nutrition
• Wheat
• Sea water
• Salt tolerance
• Triticum durum

Acknowledgments

This study was funded by the Italian Ministery of University, Scientific and Technological Research (Cofinanziamento 1999) and by the University of Pisa (Fondi di Ateneo 1999).