The Effect of Calcium on the Ripening of Avocado (Persea americana Mill.) Fruits1

Abstract

Treatment with calcium (0.1 M CaSO 4 , 0.1 M CaCl 2 ) depressed respiration of avocado fruits during preclimacteric and climacteric phases. Na 2 SO 4 was ineffective. Calcium not only inhibited respiration but delayed the onset of the climacteric and depressed the peak of ethylene production at the climacteric rise. Determinations of endogenous Ca confirmed that higher levels were positively correlated to delay in ripening and negatively correlated to peak of CO 2 and ethylene production. It is inferred that this difference in Ca level is one of the factors causing lack of uniformity in ripening.