野古草居群光合作用对光强和CO2浓度的响应特征

以移植于同一环境的辽宁地区4个野古草居群为对象,比较了它们的光合作用对光强和CO₂浓度的响应差异,为研究其居群表型性状多样性的生理基础提供参考。结果表明,野古草光合速率对光强和CO₂浓度的光合响应特征参数在居群间多数存在显著差异,居群P₁(本溪)、居群P₂(北镇)具较高的光饱和点(分别为1782和1690 μmol/m²·s)、表观量子效率(分别为0.0553和0.0564)及表观羧化效率(分别为0.0568和0.0783),较低的CO₂补偿点(分别为14和12 μmol/mol),具有较高的光能生产潜力。居群P₃(建平)、居群P₄(彰武)的气孔导度低(分别为0.1227和0.1176 mol/m²·s),蒸腾速率低(分别为2.67和2.68 mmol/m²·s),持水能力强。

Photosynthetic responses of Arundinella hirta populations to light intensity and CO2 concentration

Photosynthetic responses to light intensity and CO₂ concentration were determined in four Arundinella hirta Tanaka populations in Liaoning province in order to provide a basis for further studies of phenotypic variation in this species. Most of the characteristic parameters were significantly different among the four A. hirta populations, suggesting that there are genetic differences between them. The Benxi (P₁) and Beizhen (P₂) populations showed higher yield potentials as they had higher light saturation points (1782 and 1690 μmol/m²·s, respectively), apparent quantum yields (0.0553 and 0.0564, respectively), carboxylation efficiencies (0.0568 and 0.0783 μmol/m²·s, respectively) and lower CO₂ compensation points (14 and 12 μmol/mol), respectively. The Jianping (P₃) and Zhangwu (P₄) populations performed better with regard to drought tolerance, with lower stomata conductance (0.1227 and 0.1176 mol/m²·s, respectively) and transpiration rates (2.67 and 2.68 mmol/m²·s, respectively) and with higher water holding capacities.