3个油茶品种幼苗对干旱胁迫的生理响应

在温室内模拟不同干旱胁迫,通过盆栽试验研究了3个油茶品种‘长林4号’(C4)、‘长林23号’(C23)和‘长林53号’(C53)2年生幼苗主要生理指标的变化,并利用相关分析、主成分分析和隶属函数法对各油茶品种抗旱性进行综合评价。结果表明:(1)随着干旱程度加重和胁迫时间延长,油茶叶片相对电导率和硫代巴比妥酸反应物(TBARS)含量均有不同程度上升。(2)超氧化物歧化酶(SOD)和过氧化物酶(POD)活性均呈现先上升后下降趋势,且在干旱15d时,抗氧化酶活性达到最大。(3)叶绿素含量、净光合速率(Pn)、气孔导数(Gs)和蒸腾速率(Tr)随着胁迫程度加重和胁迫时间延长均有不同程度下降。(4)抗旱性综合评价表明,供试的3个油茶品种抗旱能力依次为C53>C4>C23。

Physiological Responses of Three Camellia oleifera in Seedling Stage under Drought Stress

The physiological and photosynthetic indexes of 2-year-old seedling of Camellia oleifera clones including Changlin 4(C₄),Changlin 23(C₂₃) and Changlin 53(C₅₃) were measured under different gradients sustainable drought stress in greenhouse,and then the drought resistance was comprehensively evaluated by correlation analysis,principal component analysis and subordinative function.The results showed that:(1)As the drought stress proceeding,the relative electric conductivity and TBARS content were increasing.(2)The activities of SOD and POD increased at first,and then decreased.The antioxidant enzyme activities were the highest after drought stress for 15 d.(3)Chlorophyll content,net photosynthetic rate,stomatal conductance and transpiration rate in leaves of C.oleifera were decreased in various degrees.(4)The order of drought tolerance was Changlin 53>Changlin 4>Changlin 23,which was accordance with the damaged symptom of C.oleifera after drought stress.