Growth and CO2 uptake for cladodes and fruit of the Crassulacean acid metabolism species Opuntia ficus‐indica during fruit development

Growth and daily net CO2 uptake were measured for fruit of Opuntia ficus‐indica and for its cladodes with 0. 5, 10 and 15 fruit and for cladodes after fruit removal. Growth of individual fruit decreased but fruit dry weight per cladode increased as the number of fruit per cladode increased. Removal of fruit decreased the total daily net CO2 uptake of the bearing cladode by about 10%. From 15 to 45 days after flowering, nocturnal CO2 uptake per unit area of the fruit averaged 19% of that of cladodes and then declined, as did the chlorophyll content and the activity of the CO2‐fixing enzymes. Fruit growth for O. ficus‐indica was supported by the bearing cladode as well as other cladodes, especially for cladodes with more than 5 fruit.