Effects of ozone and drought on fluorescence physiology of seedlings of three afforestation tree species in South China
Objective] This study was conducted to demonstrate the fluorescent physiology of ozone resist -ance and drought physiology mechanism in the seedlings of three native tree species and provide reference for screening stress-resistant tree species in South China .[Method] Seedlings of Elaeocarpus apiculatus, Mytilaria laosensis and Castanopsis fissa were treated with ozone fumigation and drought condition , and their chlorophyll fluorescence parameters were determined .[Result and conclusion] The results showed that with increasing treatment time , minimal initial fluorescence ( F0 ) of the three seedling types increased and then decreased , and their PSⅡmaximum photochemical efficiency ( Fv/Fm ) remained stable; active quantum efficiency of PSⅡ[ Y (Ⅱ) ] treated with ozone stress decreased , followed by an increase and other treatments remained stable;non-photochemical quenching ( NPQ) of E.apiculatus seedlings remained sta-ble and other seedling types increased and then decreased .Principal component analyses showed that re-sistance of the three seedling types to ozone stress and drought stress was C.fissa >E.apiculatus >M. laosensis, whereas their resistance to intercross stress of ozone and drought was E.apiculatus >C.fissa >M.laosensis.In general, the three seedling types have a certain ability to resist ozone or drought by start -ing an adjustment mechanism of photoprotection under ozone stress or drought stress .
国家科技期刊平台
NSTL
万方数据
维普
