Carbohydrate partitioning in the leaves of Bromeliaceae performing C3 photosynthesis or Crassulacean acid metabolism

Carbohydrate accumulation was measured in the leaves of 11 species representing the three subfamilies of Bromeliaceae. In the Tillandsioideae the C-3 species Vriesea carinata Wawra accumulated starch and sucrose while the Crassulacean acid metabolism (CAM) species Tillandsia tricolor Schlechtendal & Chamisso accumulated mainly starch. In the Pitcairnioideae the C-3 species Pitcairnia paniculata Ruiz & Pavon and two CAM species Dyckia sp, and Fosterella schidosperma Barker accumulated sucrose but not starch. Of six CAM species in the Bromelioideae, three Cryptanthus zonatus (Visiani) Beer, Neoregalia spectabilis Moore and Portea petropolitana Wawra accumulated starch but not soluble sugars while three (Ananus comosus Linnaeus, Orthophytum vagans M.B. Foster and Nidularium bilbergioides Schultes filius) accumulated starch as well as soluble sugars. Carbohydrate accumulation patterns were similar for species within each subfamily in that the Pitcairnioideae species did not accumulate starch but accumulated sucrose while species from the Tillandsioideae and Bromelioideae all accumulated starch (some also accumulated soluble sugars). Carbohydrate accumulation patterns were not similar for C-3 species versus CAM species from the different subfamilies. These data suggest that variations in carbohydrate biochemistry resulting from different evolutionary histories have a greater influence on carbohydrate accumulation patterns in CAM bromeliads than the constraints of the CAM pathway itself.