Light intensity selectively influences the distribution and further redistribution of macro- and micronutrients in hydroponically grown wheat (Triticum aestivum L.)

ABSTRACT

Investigations were focused on light effects on allocation of root-borne macronutrients (calcium, magnesium and potassium) and micronutrients (iron, manganese, zinc and copper) in roots, shoots and harvested grains of wheat (Triticum aestivum L.). Plants were exposed to low (100 μmol photons m⁻² s⁻¹) or high light (380 μmol photons m⁻² s⁻¹). High light stimulated both root and shoot growth. While the total contents per plant of some nutrients were markedly higher (calcium and potassium) or lower (copper) under high light, no major differences were observed for other nutrients. The distribution of nutrients and the further redistribution within the shoot were influenced by the light intensity in an element-specific manner. Nutrients were selectively directed to the leaves of the main shoot (low light) or to the tillers (high light). The quality of the harvested grains was also affected by the light intensity.

KEYWORDS:

• Grain quality
• light intensity
• macronutrient allocation
• main shoot
• micronutrient allocation
• phloem
• tiller
• Triticum aestivum
• wheat
• xylem

Acknowledgments

We thank Regula Maria Blösch for performing some preliminary experiments and the University of Bern for financial support.