沉水植物黑藻的拓殖能力和光合荧光特性

The propagation ability and photosynthetic fluorescence characteristics of submerged plant Hydrilla verticillata

应用直观测量法和水下调制荧光仪,比较分析黑藻(Hydrilla verticillat a)不同长度(5 cm、10 cm、15 cm)和不同类型(有无顶芽)断枝的再生、生长、定居等拓殖能力以及光合荧光特性.结果显示,顶芽对黑藻断枝所萌发的新枝数、再生枝干重以及平均不定根长度无显著影响(P>0.05),而对相对生长速率、相对伸长速率、不定根数量以及根冠比具有显著影响(P<0.05);由黑藻断枝萌发的新枝数、再生枝干重、相对生长速率、相对伸长速率、不定根数量、平均不定根长度和根冠比均随断枝长度的增加显著增加(P<0.05).实验期间,顶芽对各组黑藻断枝的最大量子产率(Fm/Fv)、快速光响应曲线具有显著影响(P<0.05);断枝长度对各实验组的Fm/Fv影响不显著(P>0.05),而各组黑藻的快速光响应曲线随断枝长度的增加而增大.本研究表明含顶芽15 cm的断枝具有较强的生长能力、定居能力、光合能力,有利于快速建群,可作为水生植被恢复与重建的首选.

This research compared the regeneration,growth,colonization abilities and photosynthetic fluorescence characteristics of different lengths（5 cm,10 cm,15 cm） and types（with and without apical tips） of fragments of Hydrilla verticillata to study its propagation ability and photosynthetic fluorescence in the application of direct measurement method and diving-pam.The results demonstrated that both fragments with and without tips presented similar numbers and dry weight of regenerated shoots and the same lengths of adventitious roots（P〉0.05）.However,the RGR,REG,number of adventitious roots,and the root-shoot ratio were significantly different between fragments with and without tips（P〈0.05）.The number and dry weight of shoots,RGR,RER,the number and length of adventitious roots,and the root-shoot ratio increased significantly with increasing fragment length among all treatments（P〈0.05）.Additionally,during the experiment,tips showed obvious impact on Fm/Fv and Rapid Light Curves（RLCS）（P〈0.05）,with The longer fragments showing greater RLCS than the shorter ones（P〈0.05）.There was no difference of Fm/Fv in the fragments of different lengths（P〉0.05）.Among all,fragments of 15 cm with tips had greater abilities of growth,colonization and photosynthetics than others,therefore being the best choice for the aquatic plant recovery.