Chemical Investigations on Bitter Pit of Apples

Summary Fruits of Cox’s Orange variety have been examined for size, and dry matter content, and have been analysed for minerals, nitrogen and sugars contents from just after petal fall to beyond commercial maturity, for two growing seasons. Leaves from fruiting spurs and from leaders were also analysed. Appreciable differences, especially in minerals and nitrogen contents, were found for the two seasons. Nitrogen, calcium, magnesium, potassium, sodium and phosphorus percentages decreased on the fresh and dry‐matter basis, but accumulation of these elements occurred steadily, with growth of the fruits. On the other hand leaves increased in ash, calcium, and magnesium contents, but decreased in potassium, sodium, phosphorus and nitrogen, with increasing age. Expressed on the fresh basis, leaves were much richer than fruits in all these elements, especially in the latter half of the season. On both fresh and dry basis, fructose and sucrose increased but glucose remained relatively constant, with increasing size, although the amounts of these sugars on the per‐fruit basis rose rapidly. Leaves were relatively poor in sugars. In the leaves, sucrose was relatively high when fructose was low, and vice versa. The data recorded are regarded as fundamental for the study of chemical composition in relation to bitter pit.