木兰科6种常绿树幼苗抗寒性的初步研究

对木兰科6个常绿树种在南京地区越冬期间的冻害指数、半致死温度、MDA含量及光合色素含量的变化进行了研究, 探讨供试树种的抗寒性。结果表明: 所有供试树种经过一段时间的低温锻炼后抗寒能力均增加, 中亚热带树种的冻害指数和半致死温度均要低于南亚热带树种; 越冬期间所有树种的MDA含量均显著上升, 叶绿素含量则均下降。综合上述指标对供试树种的抗寒性做出排序: 乐东拟单性木兰( Parakmeria lotungensis) >阔瓣含笑(Michelia platypetala) >金叶含笑(Michelia foveolata) >红花木莲(Manglietia insignis) >醉香含笑(Michelia macclurei) >观光木( Tsoongiodendron odorum ) 。

A Preliminary Study on Cold Resistance of Six Magnolia Species Seedlings

The performance and the physiological indices including CI,TL50,MDA and Chl.during the course of winter were investigated to study the cold resistance of six evergreen magnolia species.All species' chilling assistance was strengthened after a period of low temperature domestication.The magnolia species that distributed naturally in middle-subtropical areas had much lower CI and TL50 than that distributed naturally in sourthern-subtropical areas.All species' contents of MDA ascended while Chl.descended during the course of winter.The cold resistance of six magnolia species were arranged in sumarization of the value of above indice:Parakmeria lotungensis was the strongest,followed by Michelia platypetala,Michelia foveolata,Manglietia insignis,Michelia macclurei and Tsoongiodendron odorum.