Characteristics of Gas Exchange in Three Domesticated Anemone Species

摘要

Seeds of three Anemone species were collected from the suburban areas of Kunming and planted in a nursery for three and a half years at Kunming, Yunnan Province, China. Leaf gas exchange measurement indicated that these species had similar one-peak diurnal trends of net photosynthetic rate (PN), although A. rivularis had lower transpiration rate (TR), stomatal conductance (gs) and intercellular CO2 concentration (Ci), and higher stomatal limit in the afternoon. Species differences in response of PN to photosynthetically active radiation (PAR) were observed, especially under strong light. A. rivularis had the highest PN and Ci under strong light which corresponded with its highest gs and TR. A. rivularis had the highest light saturation point (LSP) (1000 mol m-2 s-1) and light compensation point (LCP) (69 mol m-2 s-1), while A. hupehensis var. japonica had the lowest LSP (800 ?mol m-2 s-1) and a lower LCP (53 mol m-2 s-1). But the three species responded similarly to the change of CO2 concentration in the air from 0 to 350 ?mol (CO2) mol-1, and their observed CO2 compensation point showed little difference (47, 53 and 56 ?mol (CO2) mol-1). Moreover, A. rivularis had the highest apparent quantum yield (0.032), carboxylation efficiency (0.049), PN (11.68 ?mol (CO2) m-2 s-1) and TR (5.36 mmol (H2O) m-2 s-1) based on the PN -PAR response. The results implied that A. rivularis is able to grow well under higher radiation, while A. hupehensis var. japonica is the best one to grow under partial shade.