Changes in Esterase Activity in the Abscission Zone of Jointless Tomato Fruits

Abstract

Esterase activity in the abscission region of processing tomato fruits was histochemically investigated. At the mature-green stage of fruit development, esterase activity was not detected in the juncture tissue between the ovary and receptacle. At full maturity, esterase activity had noticeable increased in the secondary xylem on the fruit side. However, as fruit ripening proceeded, esterase activity decreased rapidly, especially in the enlarged cells at the abscission zone. This result suggests that esterase may induce cell wall and plasma membrane breakdown in the abscission region in processing tomato fruits.