Varietal differences in the mineral composition of bulked samples of fruit from Cox's Orange Pippin, Crispin (Mutsu) and Spartan apple trees

Abstract

AbstractConcentrations of dry matter, nitrogen and major mineral constituents in samples of Cox's Orange Pippin and Crispin fruit from interplanted trees were measured for 4 years. Similar measurements were made over a 6 year period in Cox and Spartan fruit samples from trees interplanted in another orchard. Concentrations varied greatly in all varieties from year to year. In comparison with Cox, fruit calcium concentrations were higher for a given mean mass per apple in Crispin in all years and in Spartan for 4 of the 6 years at harvest. Concentrations of nitrogen, potassium, magnesium and phosphorus were lower in Crispin and Spartan than in Cox fruit at harvest in all years, but dry matter and sodium concentrations differed only in some years. Changes in concentrations during fruit growth were measured in 2 years for each comparison. Differences between nitrogen, phosphorus and potassium concentrations in either Crispin or Spartan and Cox apples were evident throughout fruitlet enlargement in both years. Calcium concentrations were higher in Crispin and Spartan fruitlets than in Cox fruitlets of equivalent mass. Variations in the concentrations of potassium, magnesium and calcium from tree to tree were greater for Cox than Crispin samples but relationships between potassium and magnesium concentrations were similar for both varieties.