UV-B辐射增强和氮沉降对不同种源地乌桕叶绿素荧光参数的影响

Effects of enhanced UV-B radiation and nitrogen deposition on chlorophyll fluorescence parameters of invasive plant Triadica sebifera

以来源于入侵地美国和中国本地的乌桕(Triadica sebifera)为研究对象,通过模拟UV-B辐射增强、氮沉降加剧,研究两者对不同种源地乌桕种群叶绿素荧光参数的影响。结果表明,UV-B辐射和氮沉降在乌桕株高方面存在显著交互作用,UV-B辐射和种源在F_v/F_m方面存在显著交互作用;UV-B辐射显著增加乌桕SPAD;氮沉降显著增加乌桕SPAD,降低Y(Ⅱ)、ETR_(max);氮沉降能减缓UV-B辐射对乌桕株高生长的胁迫作用;来源于入侵地美国的乌桕种群相比于中国本地乌桕种群,具有较高的实际光能转化效率和株高生长速度,较低的SPAD,并对UV-B辐射胁迫更敏感。

In order to study the effects of enhanced UV-B radiation and nitrogen deposition on chlorophyll fluorescence parameters in invasive plant Triadica sebifera,we used plant materials which came from the native land China and the invaded land US. The results showed that UV-B radiation and nitrogen deposition showed interactive effect on plant height,and UV-B radiation and origin had a significant interaction on F_v/F_m. UV-B radiation significantly increased the SPAD of T. sebifera,and nitrogen deposition significantly increased SPAD and decreased Y( Ⅱ) and ETR_(max) of T. sebifera. Nitrogen deposition could alleviate UV-B radiation stress effects on plant growth of Triadica sebifera. Compared with the local Chinese populations,the population from America showed higher light energy conversion efficiency and growth rate of height,lower SPAD and was more sensitive to UV-B radiation stress.