西藏3个种源江孜沙棘的光合作用参数分析

Photosynthesis Parameters of Three Hippophae gyantsensis Species in Tibet

为研究不同种源江孜沙棘的光合变化规律和光适应能力,以西藏自治区江孜县、 拉孜县和白朗县3个种源的江孜沙棘苗木为试验材料,用Li-6400便携式光合仪测定其光合光响应曲线,应用直角双曲线修正模型估算不同种源的江孜沙棘其光饱和点、 光补偿点、 最大净光合速率等光合参数,并进行分析.结果表明:拉孜县种源的江孜沙棘其最大净光合速率最高、 暗呼吸速率最大、 光补偿点较小、 光饱和点最大、 表观量子效率最大,并且生物量最高;江孜县种源的江孜沙棘其光补偿点最大,其各光合指标最小;可通过比叶面积的变化趋势判定植物光合参数变化.3个种源的江孜沙棘中,拉孜县种源其适应光合逆境的能力最强,具有较高的推广应用价值.

In order to study the photosynthetic changes and light adaptability of Hippophae gyantsensis from 3 provenances namely Jiangzi,Lazi and Bailang County in Tibet Autonomous Region,photosynthetic light were measured by Li-6400 portable photosynthetic apparatus.The right-angle hyperbolic correction model was used to estimate the photosynthetic parameters such as light saturation point,light compensation point and maximum net photosynthetic rate of different provenances H.gyantsensis.The results showed that the maximum net photosynthetic rate,the dark respiration rate,the light compensation point,the maximum apparent light efficiency and the highest biomass were the highest in the provenance H.gyantsensis of Lazi.The light compensation point of Jiangzi H.gyantsensis was the largest,and its other photosynthetic index were the smallest;the change of plant photosynthetic parameters could be determined by the change trend of specific leaf area.Among 3 provenances,the source of Lazi has the strongest ability to adapt to photosynthetic stress,and has a high value for future popularization and application.