How Is Photosystem II Activited in the Leaves and Assimilative Branches of Alhagi Sparsifolia Shap. under Brief Elevated Temperature

Alhagi sparsifolia is the primary vegetation in the forelands of Taklamakan Desert, the largest mobile desert in China. It plays an important role in wind prevention and sand fixation in the forelands. With global warming, an increase in temperature above the optimal level for plant growth may lead to deterioration of the structure and function of proteins involved in photosynthesis and decrease of photosynthesis efficiency.

Therefore, researches wanted to understand the consequences of climate change on photosynthetic activity and plant productivity in extremely arid environments like Taklamakan Desert. LI Lei et al., by investigating the kinetics of induced chlorophyll α fluorescence under heat-stress-induced inhibition of photosystem II in leaves and assimilative branches of A. sparsifolia developed in Taklamakan Desert, explored the roles of leaves and assimilative branches of A. sparsifolia in global warming. They also studied whether the leaves and assimilative branches of A. sparsifolia have the same response and tolerance to different temperatures.

The results present that both the activity and density of reaction centers of leaves are higher than that of assimilative branch at 35–48°C, and both in the leaves and assimilative branches were decreased above 45°C. Furthermore, the assimilative branches adapted better to the severe environment in terms of light energy transfer, light usage efficiency, and electron transport at 52°C. That is, assimilative branches might be more adaptive to severe environment.

The findings of the study can improve a reference for understanding the consequences of climate change on vegetation deterioration in arid environments. The study was published in Acta Physiologiae Plantarum in July 2014.