库布齐沙地6种植物叶绿素荧光参数比较

Differentiation of chlorophyll fluorescence parameters of six plants species in the Kubuqi sandy land

利用便携式叶绿素荧光分析仪测定了库布齐沙地油蒿(Artemisia ordosica)、中间锦鸡儿(Caragana inter-media)、羊柴(Hedysarum laev)、沙柳(Salix cheilophila)、紫花苜蓿(Medicago sativa)和达乌里胡枝子(Lespe-deza davurica)的叶绿素荧光参数。结果表明,固定荧光(F0)、最大荧光(Fm)、PSⅡ的潜在活性(Fv/F0)、PSⅡ最大光学效率(Fv/Fm)、光化淬灭系数(qP)、非光化学淬灭系数(NPQ)、PSⅡ实际光化学效率(Yield)7项叶绿素荧光参数表现出不同程度的差异。在6种沙地植物中,中间锦鸡儿、羊柴、沙柳、油蒿4种灌木植物的Fm、Fv/F0、Fv/Fm、qP、Yield值均显著(P<0.05)高于草本状半灌木达乌里胡枝子和草本植物紫花苜蓿,这表明中间锦鸡儿、羊柴、沙柳、油蒿的光合能力大于达乌里胡枝子和紫花苜蓿。然而,达乌里胡枝子和紫花苜蓿的NPQ显著高于中间锦鸡儿、羊柴、油蒿、沙柳,说明紫花苜蓿和达乌里胡枝子的叶片通过热耗散的能量较多,这两种植物通过热耗散消耗掉过剩光能,从而避免了沙地强光环境对光合机构的破坏。

The PAM-2100 portable chlorophyll fluorescence analyzer was used to measure and compare the chlorophyll fluorescence parameters of Artemisia ordosica , Caragana intermedia , Hedysarum lacy, Salix cheilophila, Medicago sativa and Lespedeza davurica in the Kubuqi sandy land. This study showed that the minimal fluorescence （F0）, the maximal fluorescence （Fro）, the ratio of variable fluorescence to initial fluorescence （Fv/F0）, the potential efficiency of primary conversion of light energy of PS Ⅱ （Fv/Fm）, the photochemical quenching coefficien （qP）, the non-photochemical quenching coefficient （NPQ） and the actual photochemical efficiency of PS Ⅱ in the light （Yield） was different among six plant species. Fm, Fv/F0 , Fv/Fm, qP and Yield of C. intermedia, H. leave, S. cheilophila and A. ordosica were significantly higher than those of L. davurica and M. sativa. These results showed that the photosynthetic abilities of C. intermedia, H. leave, S. cheilophila and A. ordosica were greater than those of L. davurica and M. sativa, and the NPQ of L. davurica and M. sativa were higher than those of C. intermedia, H. leave, S. cheilophila and A. ordosica, indicating that L. davurica and M. sativa consumed excessive light energy by heat dissipation and protected photosynthetic organs from glare conditions in the sandy land environments.