11种人工栽培树木叶绿素荧光特征比较

Comparison on Chlorophyll Fluorescence Characters in Eleven Cultivated Tree Species in the Karamay Agricultural Development Region

测定比较了新疆克拉玛依农业开发区人工栽培的11种树木的初始荧光(Fo)、最大荧光(Fm)、PSⅡ最大光能转化效率(Fv/Fm)和PSⅡ最大光能转化潜力(Fv/Fo)4个叶绿素荧光参数随太阳总辐射、空气温度和空气相对湿度的日变化,以及不同作用光强下从初始荧光上升到最大荧光一半所需时间(T1/2)的变化特征。结果表明: 11种树木的叶绿素荧光参数Fo,Fm,Fv/Fm和Fv/Fo的种间差异达到了极显著水平(P<0.001),在时间序列上Fo表现为差异显著(P<0.05),Fm,Fv/Fm和Fv/Fo表现为差异极显著(P<0.001);大叶白蜡、梓树和圆冠榆的Fv/Fm日均值处于较低状态,且大叶白蜡的Fv/Fm和Fv/Fo日均值显著低于其他树种;胡杨、沙枣和馒头柳的Fv/Fm值全天保持较高水平,并且胡杨和沙枣在10:00左右出现光合"小憩"现象;除胡杨、沙枣和馒头柳的叶绿素荧光参数T 1/2下午与上午相比变化不很明显外,其他树种均有不同程度的降低,表明下午的强光、高温和低空气湿度使得PSⅡ活性下调,PSⅡ光合电子传递链受阻,从而发生了光抑制。测试树种耐光抑制能力的强弱为:胡杨、沙枣、馒头柳耐光抑制最强,俄罗斯杨、天演杨、银×新、新疆杨、白榆其次,大叶白蜡、梓树、圆冠榆耐光抑制最弱。

This paper determines and compares the diurnal variation of 4 chlorophyll fluorescence parameters including the initial fluorescence（Fo）,maximal fluorescence（Fm）,maximal efficiency of primary conversion of sunshine energy of PSⅡ（Fv/Fm）,and maximal potential of primary conversion of sunshine energy of PS II（Fv/ Fo）along with variation of three environment factors including solar radiation,air temperature,air relative humidity and character of T1/2 under different sunshine intensity in 11 tree species.The results show that there are the extremely significant differences in Fo,Fm,Fv/Fm and Fv/Fo（P〈0.001）among the 11 tree species.The difference in Fo is significant（P〈0.05）on the level of time series,and the differences in Fm,Fv/Fm and Fv/ Fo are extremely significant（P〈0.001）on the level of time series.The value of Fv/Fm of Fraxinus rhynchopylla Hance,Catalpa ovata G.Don,and Ulmus densa Litv.retained on a lower level during the whole diurnal variation process,and the averages of Fv/Fm and Fv/Fo of Fraxinus rhynchopylla Hance are obviously lower than that of the others.The values of Fv/Fm of Populus euphratica Oliv.,Elaeagnus angustifolia L.,and Salix matsudana var. matsudana f.umbraculifera Rehd.maintain a higher level,and photosynthetic＂rest＂occurs to Populus euphratica Oliv.and Elaeagnus angustifolia L.at 10：00 o＇clock.Except the change of T1/2 of Populus euphratica Oliv. Elaeagnus angustifolia L.,and Salix matsudana var.matsudana f.umbraculifera is not so evident at p.m.compared with the same value at a.m.,T1/2 of other tree species is decreased to a certain extent,which reveals that the photosynthetic activity is decreased and the PSⅡelectron transport is inhibited after the strong sunshine,high air temperature and low air relative humidity.The capability of resisting sunshine inhibition of Populus euphratica Oliv.Elaeagnus angustifolia L.,and Salix matsudana var.matsudana f.umbraculifer is the highest,that of Populus alba×P.alba var.pyramidalis Bge.,Populus russkii Jabl.,Tianyan yang,Populus alba×P.alba var.pyramidalis Bge.,Populus alba var.pyramidalis Bge.and Ulmus pumila L.is moderate,and that of Fraxinus rhynchopylla Hance,Catalpa ovata C.Don,and Ulmus densa Litv.is the lowest.