Dissolved Carbon Dioxide and the Ripening of Tomatoes

Abstract

THE phenomenon of climacteric rise in respiration of ripening fruits is not fully understood. Blackman and Parija¹ explained the rise in respiratory activity in apples on the assumption that in the senescent stage a lowering of ” hydrolysis-resistance” occurs leading to a greater production of effective substrate for respiration. Kidd and West² have attributed the initial increase in carbon dioxide output during senescence to the action of some ” protoplasmic factor”. Gustafson³ has demonstrated that the rate of respiration is very greatly influenced by the pH of the cell-sap, lower values of pH being usually associated with higher rates of respiration, and in a later communication⁴ suggests that the climacteric rise is probably due to a lowering of pH, of the cell-sap.