非洲菊光合特性研究

对温室栽培条件下非洲菊(Gerbera hybrida var. diablo)开花前、开花期、开花后三个生育期的光合特性进行初步探讨。结果表明,开花前CO₂浓度为600μmol/mol时,净光合速率(Pn)为8.23 CO₂μmol/m²·s,比在大气CO₂浓度下高27.1%;开花期非洲菊的表观量子效率较小,比开花前、开花后分别低40.0%和37.2%,CO₂补偿点为59μmol/mol,比开花前、开花后分别低45.8%和55.9%,三个生育期的CO₂饱和点差别不明显,开花后的羧化效率(CE)较低;开花后叶片叶绿素含量下降,但三个生育期的净光合速率相近(6.0CO₂μmol/m²·s左右)。非洲菊的光合日变化在晴天呈不太明显的双峰型,最大净光合速率出现在11:00左右,为7.77 CO₂μmol/m²·s,次峰值出现在1500左右,小于首峰值。

Studies on Photosynthetic Characteristics of Gerbera hybrida var. diablo

The photosynthetic characteristics of leaves of Gerbera hybrida var. diablo under greenhouse conditions before, during and after flowering stages were studied. The results were as follows:Pn (about 8.23 CO₂μmol/m²·s) under elevated CO₂ concentration (600μmol/mol) was 27.1% higher than that under ambient CO₂ concentration before flowering; the apparent quantum efficiency at flowering stage was 37.2% and 40.0% lower than that before flowering and after flowering, respectively, while the CO₂ compensate point was 45.8% and 55.9% lower, respectively; the chlorophyll content in leaf after flowering was lower in comparison to those before and during flowering stages; the net photosynthetic rate at three stages had a similar value (about 6.0 CO₂μmol/m²·s); the diurnal variation on net photosynthetic rate of Gerbera hybrida var. diablo in sunny days presented bimodal curve, the first peak occurred at about 11:00,which was 7.77 CO₂μmol/m²·s, the second peak occurred at about 15:00 and the value was lower than the first one.