UPTAKE OF NUTRIENTS BY THE APPLE FRUIT

Mineral concentrations (fresh matter basis) in the apple fruitlet at petal fall approximate to those in the stalk and to the tree wood.
As the stalk grows, concentrations of some nutrients in it drop (e.g. nitrogen) whilst others, especially phosphorus, increase.
At harvest, the calcium concentration is extremely high and the total amount in the stalk accounts for 5–10 per cent of that in a whole Cox’s Orange Pippin fruit.

Cox’s Orange Pippin seeds grow rapidly, reaching full size ten weeks after full bloom.
Uptake of nutrients other than potassium is maintained by the seeds throughout and after this period, and total amounts of nitrogen, phosphorus, magnesium and calcium at harvest account for about 10–15 per cent of those in the whole apple.

Uptake of most nutrients is maintained throughout the growth of the receptacle (core, flesh and peel) until harvest but concentrations of most elements drop, although the early rapid decreases are masked by similar decreases in dry matter if concentrations are expressed on a dry matter basis.
In the last few weeks before harvest calcium may move into or out of the receptacle and there is an influx of sodium.

Symposium on Mineral Nutrition and Fruit Quality of Temperate Zone Fruit Trees

M.A. PERRING

https://doi.org/10.17660/ActaHortic.1980.92.29