拉萨大花黄牡丹变异材料的光合特性研究

Photosynthetic Characteristics of Paeonia ludlowii Variant Material in Lhasa

旨在探索大花黄牡丹(Paeonia ludlowii)发生变异(花瓣重瓣化/抗性增强)是否与它的光合特性有关。分别选取大花黄牡丹变异材料AS和非变异材料ACK,采用Li-6400便携式光合仪测定其光合特性,分析变异和非变异大花黄牡丹在同等环境条件下的光合特性差异。结果表明:与非变异材料ACK相比,变异材料AS的净光合速率受CO2浓度的变化影响较大,而受光强度的影响较弱;且AS的净光合速率低于材料ACK,最大净光合速率和光饱和点显著高于非变异材料,二者最大净光合速率分别为49.8μmol/(m^2·s)和41.6μmol/(m^2·s),光饱和点分别为754.5μmol/(m^2·s)和334.2μmol/(m^2·s);暗呼吸速率和表观量子效率极显著低于非变异材料,AS和ACK的暗呼吸速率分别为0.039μmol/(m^2·s)和0.178μmol/(m^2·s),表观量子效率分别为0.066μmol/mol和0.125μmol/mol。本研究表明,拉萨大花黄牡丹变异材料的光合特性发生了明显变化,且适应环境能力较同品种非变异材料增强,能够较好地适应相对恶劣的环境;由此可见,大花黄牡丹发生变异极可能与其光合特性的特异性有关,然而,变异材料在其他坏境条件下的可能性应该被进一步探索发觉。

The aim is to investigate whether the variation petals re-flap and resistance enhancement are associated with the photosynthetic features of Paeonia ludlowii.Paeonia ludlowii mutant AS and non-mutant ACK are used as materials.The photosynthesis parameters are measured using Li-6400 portable photosynthetic system.The differences of photosynthetic characteristics of Paeonia ludlowii mutant AS and non-mutant ACK are analyzed under the similar environmental conditions.The results showed that:compared to ACK,the net photosynthetic rate of AS was greatly affected by the changes of CO2 concentration,while marginally affected by the light intensity.AS had lower net photosynthetic rate,but significantly greater maximum net photosynthetic rate and light saturation point than those of ACK.The maximum net photosynthetic rate of AS and ACK was 49.8 and 41.6μmol/(m^2·s),respectively,and the light saturation point was 754.5 and 334.2μmol/(m^2·s),respectively.The dark respiration rate in AS was markedly lower than that in ACK[0.039 vs.0.178μmol/(m^2·s)],as well as the apparent quantum yield in the mutant was markedly lower than that in the non-mutant(0.066 vs.0.125μmol/mol).The results suggest that the mutant material Lhasa Paeonia ludlowii has significantly varied photosynthetic characteristics and enhanced ability of environmental adaption than its non-variant material,indicating that the variation of Paeonia ludlowii was specifically related to its photosynthetic characteristics under the present conditions,while the additional possibilities of mutation in other environmental conditions should be further exploited.