Artículos de revistas
Photosynthetic response of two tropical liana species grown under different irradiances
Registro en:
Photosynthetica. Springer, v. 46, n. 4, n. 557, n. 566, 2008.
0300-3604
WOS:000261579100012
10.1007/s11099-008-0094-9
Autor
Sanches, MC
Vaio, IFM
Institución
Resumen
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) We investigated the characteristics of gaseous exchanges and chlorophyll a fluorescence under different irradiances in two liana species Canavalia parviflora Benth. (Fabaceae) and Gouania virgata Reissk (Rhamnaceae), both of a semi-deciduous tropical forest of Southeast Brazil. We used cultivated plants growing under irradiances of 100, 40, 10, and 1.5 % of the photosynthetic photon flux density (PPFD). Higher net photosynthetic rates (P(N)) were observed during early morning under full sunlight. After this, reduced P(N) values were recorded due to pronounced stomatal closure. In Canavalia, the gas exchange responses diminished concomitant with reduced irradiance. Gouania exhibited a narrower range of response, with high P(N) values even at 10 % PPFD. Marked reduction of the effective photochemical yield (Delta F/F(m)') near midday was observed, followed by increases in the non-photochemical quenching for both species under full sunlight. Despite the common occurrence of these species in open areas of the forest, both were able to maintain relatively high P(N) in shaded environments. We suggest that lianas present an intermediate physiological behaviour between shade and non-shade tolerant species. 46 4 557 566 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)