臭氧与干旱胁迫对盆架子和海南蒲桃幼苗荧光生理的影响

Effects of Ozone and Drought on Fluorescence Physiology of Alstonia scholaris and Syzygium hainanense Seedlings

以臭氧和干旱交叉胁迫下盆架子Alstonia scholaris和海南蒲桃Syzygium hainanense为研究对象,测定其荧光参数变化,为华南地区选择抗逆树种提供参考。对2种幼苗进行人工臭氧熏气和干旱处理后,用荧光仪测定其叶绿素荧光参数的动态。随着胁迫时间的延长,盆架子幼苗的最小初始荧光F0无显著变化,海南蒲桃幼苗则呈上升趋势。盆架子幼苗的Fv/Fm呈下降趋势,海南蒲桃幼苗先升后降或波动。E150处理的两种幼苗的PSⅡ实际光量子效率先降后升,其余处理的呈下降趋势。E20、E40+D和E150处理的盆架子幼苗的NPQ显著上升后降,其余处理的盆架子幼苗和所有处理的海南蒲桃幼苗呈下降趋势。研究表明,盆架子幼苗的抗臭氧或干旱能力强于海南蒲桃幼苗,适宜作为抗臭氧或干旱的树种。

This study was conducted to understand the fluorescent physiology under cross stress of ozone and drought in Alstonia scholaris and Syzygium hainanense seedlings in order to provide reference for choosing stress-resistant tree species in South China. A. scholaris and S. hainanense seedlings were treated with ozone fumigation and drought treatment,and then their chlorophyll fluorescence parameters were determined using fluorimeter. The results showed that with increasing treatment time, there was nosignificant change in minimal initial fluorescence(F0) for A. scholaris seedlings, whereas that of S. hainanense seedlings tended to increase. PSⅡ maximum photochemical efficiency(Fv/Fm) of A. scholaris seedlings tended to decrease, whereas that of S. hainanense increased followed by a decrease. Active quantum efficiency of PSII [Y(Ⅱ)] of the seedlings of two species treated with E150 decreased followed by an increase, whereas those treated with other methods tended to decrease. Non-photochemical quenching(NPQ) of A. scholaris seedlings treated with E20、E40+D and E150 increased followed by a decrease, whereas that treated with other methods and S. hainanense seedlings treated with all methods tended to decrease.We concluded that the ability to resist ozone or drought of A. scholaris seedlings was stronger than S. hainanense seedlings.