涝渍胁迫下5种菊花近缘种属植物生理特性

Physiological characteristics in five related species of Dendranthema under Waterlogging

采用土培模拟涝害的方法,对5种菊花近缘种属植物的根系活力、叶绿素含量和光合生理特性以及涝渍胁迫后的形态表现进行研究和观察,比较了其耐涝能力。结果表明:涝渍胁迫下,5种菊花近缘种属植物根系活力急剧下降,但紫花野菊在胁迫初期表现出强的根系活力;5种植物叶绿素含量总体呈现先升后降的趋势;涝渍胁迫15d时纪伊潮菊、泡黄金菊的光合强度明显降低,CO2同化作用下降,并出现负值,叶片已丧失光合作用能力,其次是大岛野路菊和那贺川野菊,而紫花野菊维持了一定水平的净光合速率。结合叶片外观形态观察发现,紫花野菊最为耐涝,泡黄金菊最不耐涝,而大岛野路菊、纪伊潮菊和那贺川野菊的耐涝性介于两者之间。

The Effects of waterlogging on root vigor,chlorophyll content,photosynthetic characteristics and morphological changes in five related species of Dendranthema were studied.The waterlogging was mimicked by treating pot plants with flooding（2-3 cm in depth）.Waterlogging tolerance of five species was evaluated.The results showed that the root vigor of five species all declined significantly under waterlogging,except that Dendranthema zawadskii showed high root vigor in the early stage of waterlogging stress.The chlorophyll contents of the five species increased during the early stages of stress and then decreased afterwards;After flooding treatment for 15d,in Ajania shiwogiku Kitam.var.kinokuniense and Dendranthema boreale,the net photosynthetic rate declined significantly,CO2 assimilation declined as well and even decreased to negative value which suggests that photosynthetic capacity was lost.Obvious decrease in photosynthetic rate was also observed in Dendranthema crassum and Dendranthema yoshinaganthum.However,Dendranthema zawadskii maintained higher net photosynthetic rate under the stress.The leaf morphological changes under the waterlogging suggested that Dendranthema zawadskii is most tolerant species,whereas Dendranthema boreale is the most sensitive species,Dendranthema crassum,Ajania shiwogiku Kitam.var.kinokuniense and Dendranthema yoshinaganthum showed moderate tolerant to waterlogging stress.