A microculture method for assessing nutrient uptake II. The effect of temperature on manganese uptake and toxicity in potato shoots

Abstract

Using standard microculture techniques for propagating potato (Solanum tuberosum L.cv. Norland), the effects of three temperature (20, 25, 30 °C) and two phosphate treatments (1.25, 2.5 mM) on the expression of Mn toxicity were investigated. Foliar yields were maximal at low temperature, but phosphate increased yield of high temperature treatments, particularly at high Mn. The uptake of Mn and severity of visual symptoms of toxicity increased with P level. A reduction in yield due to high temperature also brought about high Mn concentrations and an increase in Mn toxicity symptoms. Lateral buds developed rapidly under high Mn resulting in short highly branched shoots at high temperature. The increased severity of Mn toxicity at high temperature was attributed to an interaction between growth rate and Mn tolerance.