Nodule phosphorus and nodule activity in white clover

摘要

Abstract Rooted cuttings established from stolon tips ofa genotype of Trifolium repens cv. ‘Grasslands Huia’ white clover were grown in batch nutrient solution at a range of phosphorus (P) supplies. Growth, the concentration of nitrogen (N) and P in plant parts, the concentration ofP fractions in leaves and nodules, and the rate of ethylene production by detached root systems were measured. Shoot and total plant dry weight increased over the whole range of P supply but root dry weight (including nodules) was saturated at the higher levels of supply. The total concentration of P in leaves and nodules increased with supply, it being always higher in the nodules than in the leaves especially at low levels of supply. The concentrations of all the P fractions in the nodules and leaves increased with P supply, and were higher in the nodules than in the leaves. Inorganic-P concentrations did not change over the lower levels of supply but then changed markedly, showing greater overall increases than the other fra...