地涌金莲及红苞地涌金莲对光和CO2的响应

比较分析了地涌金莲原种及红苞地涌金莲变种的光响应和CO2响应特征以及叶绿素含量等指标.结果表明:(1)在Pn-PAR中,地涌金莲原种的最大光饱和净光合速率、光补偿点和暗呼吸速率分别较红苞变种高20.42％、34.88％、31.95％,而光饱和点却较红苞变种低4.95％；Pn-Ci响应的各参数中,原种的光呼吸速率、CO2饱和最大净光合速率以及羧化效率分别高于红苞变种2.73％、14.79％、21.35％,说明地涌金莲的光合能力要强于红苞地涌金莲；(2)地涌金莲具有典型的C3植物特征；(3)地涌金莲为阳性耐荫植物；(4)地涌金莲的叶绿素a、b以及a/b的含量分别高于红苞地涌金莲22.60％、32.46％、25.06％.

The Photosynthetic Response of Musella lasiocarpa and M. lasiocarpa var. rubribracteata to Light Intensity and CO2 Concentration

The photosynthetic responses of Musella lasiocarpa and M. lasiocarpa var. rubribracteata to light intensity and CO₂ concentration were measured with Licor-6400. The results showed that the maximum light-saturated net photosynthetic rate (Pmax), light compensation point(LCP)and dark respiratory rate(Rd)of the protospecies were higher than those of the variety by 20.42%, 34.88%, and 31.95%. But the light saturation point(LSP)was lower in the protospecies than that of the variety. The Pn-Ci curves revealed that the protospecies had higher photorespiratory rate (Rp), carboxylation efficiency (CE), and maximum CO₂ concentration-saturated net photosynthetic rate(Amax)than those of the variety by 2.73%, 14.79%, and 21.35%. This indicated that the photosynthetic capacity of the protospecies was stronger than that of the variety. The results also showed that M. lasiocarpa was a heliophile C₃ type plant, and a shade-tolerant plant as well. The chlorophyll a, b and a/b content of the protospecies were also higher than those of the variety by 22.60%, 32.46%, and 25.06%.