The actual (A) and potential (Apot) photosynthetic rates of C3 and C4 tropical crop species grown under greenhouse conditions was compared. The following species were investigated: Oryza sativa, Phaseolus vulgaris, Glycine max, Helianthus annuus, Gossypium hirsutum, Manihot esculenta, Theobroma cacao, Coffea arabica, Hevea brasiliensis, and Eucalyptus urophylla × E. grandis, all from the C3 group, and Amaranthus sp., Panicum maximum, Pennisetum purpureum, Zea mays and Saccharum officinarum, from the C4 group. A, determined under non-limiting light at ambient temperature and CO2, was measured with an infrared gas analyser, whilst Apot, determined under saturating light and CO2 at an optimal temperature (35 ºC for all species), was gauged with a gas-phase... |