遮荫对5种园林植物光合特性的影响

研究了遮荫对5种园林植物光合特性的影响。试验结果表明:在有效光辐射为50~100μmol/(m2·s)时,净光合速率呈先迅速增加、后明显降低的变化规律,其中,江南星蕨(Microsorum fortunei)和阔叶凤尾蕨(Pteris esquirolii)的净光合速率为1 200μmol/(m2·s),其光补偿点分别为10.25和9.35μmol/(m2·s);鸟尾花(Crossandra infundibuliformis)、珊瑚花(Cyrtanthera carnea)和叉花草(Strobilanthes hamiltoniana)的净光合速率接近1 500μmol/(m2·s),光补偿点依次为32.66,16.95和18.78μmol/(m2·s);在60%和85%遮荫下分别测定光能利用率的净光合速率及蒸腾速率日变化,总趋势与净光合速率和光补偿点的变化趋势相似,证明江南星蕨和阔叶凤尾蕨是喜阴植物,鸟尾花、叉花草和珊瑚花具有一定的耐荫性。

Influence of shading on photosynthetic characteristics of five species of garden plants

The influence of shading on five species of garden plants was studied.The results indicated that the net photosynthetic rate(NPR)of tested plants was increased and then decreased when the photosynthetic active radiation changed from 50 to 100 μmol/m2 ·s.The NPR of Microsorum fortune and Pteris esquirolii was 200μmol/m2 ·s while the light compensation points were 10.25 μmol/m2 ·s and 9.35 μmol/m2 ·s.The NPRs of Crossandra infundibuliformis ,Cyrtanthera carnea and Strobilanthes hamiltoniana were close to 1 500μmol/m2 ·s while the light compensation point of them were 32.66 μmol/m2 ·s,1 6.95 μmol/m2 ·s and 18.78μmol/m2 ·s respectively.Under the shading levels of 60% and 85%,the daily variation patterns of light utility efficiency,NPR and transpiration rate were similar to that of light compensation point.The results suggested that M.fortune and P .esquirolii were sciophilous plants,C.infundibuliformis ,C.carnea and S .hamiltoniana were shade tolerant plants.