[1] Hsch Geisenheim Univ, Dept Plant Nutr & Soil Sci, Geisenheim, Germany
[2] Univ Hohenheim, Inst Crop Sci, Dept Qual Plant Prod, Emil Wolff Str 25, D-70599 Stuttgart, Germany
[3] Humboldt Univ, Albrecht Daniel Thaer Inst Agr & Hort Sci, Fac Life Sci, Div Controlled Environm Hort, Berlin, Germany
[4] Univ Hohenheim, Inst Crop Sci, Dept Physiol Yield Stabil, Stuttgart, Germany