Photosynthetic properties on four cultivars of strawberry

A portable photosynthesis system made by PP-SYSTEM Ltd. was used to study the photosynthetic properties of individual leaves on 4 cultivars (Dajiangjun, Maliya, Xiangfei, Meixiangsha) of strawberry under the field conditions. The results indicated that the individual leave net photosynthetic rates, stomatal conductance and water using efficiency had 2 peaks during a day. An obvious midday depression was observed. There was a significant difference in midday depression, maximum net photosynthetic rate and water using efficiency among the four cultivars. Stoma was not a major regulation factor of midday depression. A relationship was also found between net photosynthetic rates and chlorophyll content.