非洲菊光合特性研究

Studies on Photosynthetic Characteristics of Gerbera hybrida var. diablo

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1100 左右,为7.77 CO2μmol/m2·s,次峰值出现在1500 左右,小于首峰值。

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.