Effect of drought stress on photosynthetic characteristic of six tree species

Six tree species(Ormosia hosiei Hemsl.et Wils,Photinia×fraseri 'Red Robin',Schima superba,Zelkova schneideriana,Salix×jiangsuensis cv.'J172',Prunus cerasifera 'Hollywood') were conducted to compare the difference of photosynthetic characteristic and drought resistance.Results showed that there were great differences of photosynthetic characteristics of these six tree species during 10 d drought stress period.Photosynthesis of Prunus cerasifera 'Hollywood' and Salix jiangsuensis cv.'J172' were much more sensitive to drought stress,of which there were significant decline of photosynthesis after 10 d drought stress due to stomatal limitation.In Zelkova schneideriana,stomatal limitation appeared after 4 d drought stress,however,the photosynthesis level return to normal level in the 10th day.In contrast,there was no stomatal limitation in Ormosia hosiei Hemsl.et Wils,Photinia fraseri 'Red Robin' and Schima superba during drought stress period.According to the Ci and Ca ratio of six tree species of normal irrigation during the 10 d period,the drought resistant ability arranged in descending order was Ormosia hosiei Hemsl.et Wils,Schima superba,Zelkova schneideriana,Photinia fraseri 'Red Robin',Salix jiangsuensis cv.'J172',Prunus cerasifera 'Hollywood'.