Physiological responses in Macadamia integrifolia on exposure to manganese treatment

Abstract

Macadamia integrifolia Maiden Betche (Proteaceae) from eastern Australia is farmed for its edible nuts and is capable of accumulating high foliar concentrations of manganese (Mn). It was investigated here in a pot trial, where a range of physiological responses to Mn treatment were measured. Although Mn uptake was initially slow, final foliar concentrations increased linearly with treatment levels. The highest observed mean foliar concentration of Mn was 7900gg-1 dry weight (dwt). No negative effect of Mn accumulation on plant growth was apparent, even at the highest treatment concentration. Two groups of plants, each exposed to either full sunlight or part shade were identically treated wit..