INFLUENCE DE L’ECLAIRAGE D’APPOINT SUR LA NUTRITION MINERALE DE LA TOMATE DE SERRE

Abstract

Supplementary lighting using high-pressure-sodium (HPS) lamps modified mineral nutrition of greenhouse tomato (Lycopersicon esculentum Mill.) and increased water uptake. Supplementary lighting of 30 and 60 W m−2 (PAR) increased water uptake by 35 and 70%, respectively. Nitrate, phosphate and calcium uptake was also increased. The highest irradiance (60 W m−2) increased potassium, magnesium and manganese uptake. Calcium and magnesium concentration in foliar tissues increased with irradiance, but at the same time nitrogen, potassium, phosphorus and sodium concentration decreased. The effect of nitrogen metabolism on cation uptake could partially explain the results.Key words: Tomato, supplementary HPS lighting, irradiance, mineral nutrition, Lycopersicon esculentum Mill.