Effects of Daylength on Flowering, Growth, and CAM of Pineapple (Ananas comosus [L.] Merrill)

The `Smooth Cayenne' pineapple is a quantitative short-day plant. Promotion of flowering does not require either a diurnal variation in temperature or temperatures below 25 C. Growth as total dry matter increased with daylength from 8 to 16 h, and Crassulacean acid metabolism (CAM) was operative over the same range. Leaf length and width increased over the range of 8-12 h, but leaf thickness was inversely related to daylength. We conclude that flowering in pineapple is controlled by daylength and not directly influenced by dry weight or by CAM.