Tomato responses to ammonium and nitrate nutrition under controlled root-zone pH

摘要: Tomato (Lycopersicon esculentum L. Mill. 'Vendor') plants were grown for 21 days in flowing solution culture with N supplied as either 1.0 mM NO3- or NH4+. Acidity the solutions was automatically maintained at pH 6.0. Accumulation and distribution of dry matter total net photosynthetic rate not affected by source N. Thus, when rhizosphere acidity controlled 6.0 during uptake, NH4+ can be used efficiently tomato. Uptake K+ Ca2+ altered source, but uptake Mg2+ reduced NH4(+)-fed plants. This indicates that regulated least partially ionic balance within plant.