MINERAL ELEMENT GRADIENTS IN PEARS

Concentration gradients for 10 chemical elements in pear fruits (Pyrus communis Linn.) were determined. Contents of P, K, Ca, Mn, Cu and B were high in the skin and core and low in the flesh. Al and Zn were very high in the skin and very low in both the flesh and core. Mineral content also varied between the calyx half and the stem half of the fruit‐K, Ca, Mg, and Mn were higher in the calyx half; P, Fe, Cu, Al and Zn were the same in both halves; and B was higher in the stem half of the fruit. the russet skin contained more Ca, Mn and Al than did smooth skin; quantities of the other elements were the same in both types of skin. Fruit with many stone cells contained less P, K, Ca, Mg, Mn and B than did fruit with few stone cells. the difference between the cores accounted for most of the difference. Isolated grit cells were very low in minerals with the exception of Ca. Copyright © 1969 John Wiley & Sons, Ltd