植物叶绿素含量与大气中SO2浓度相关性研究

本文对厦门市5个样点、6种常见绿化树种及盆栽植物蕹菜的叶绿素含量、叶片含硫量及大气中SO_2浓度分析测定,得出了6种植物叶绿素a、b变化趋势是:鼓浪屿、厦门大学>火车站、后江埭>电化厂;叶片含硫量的变化趋势与叶绿素a、b含量变化相反。表明植物叶片叶绿素含量与大气中SO_2浓度和叶片含硫量呈负相关,并计算蕹菜叶绿素含量与大气SO_2浓度相关模式(y=-0.0138x 0.1958),为大气环境评价提供生物学依据。     

蚕豆叶片SOD活性监测大气SO2污染的可行性研究

 本文从实验室熏气和野外大气暴露两方面对利用蚕豆叶片SOD活性评价和监测大气SO2污染的可行性进行了研究。低浓度SO2(0.1312、0.2601mg·m-3)处理,引起叶片SOD活性升高,一定时间后,SOD活性趋于稳定,且0.2601mg·m-3SO2处理时,SOD活性较高,表现出SOD活性增量与SO2浓度相关,为利用SOD活性监测和评价SO2污染提供了可能性。大气暴露试验结果表明SOD活性与大气硫酸盐化速率存在极显著的相关性。利用SOD活性和大气硫酸盐化速率分别对大气SO2污染程度进行了评价,结果基本一致,并根据SOD活性估测了大气硫酸盐化速率,符合程度较高,置信分析表明估测结果可信。以上结果表明,利用蚕豆叶片SOD活性监测和评价大气SO2污染是可行的。     

深圳7种园林植物叶绿素荧光特性及其对大气SO2浓度的响应

叶绿素荧光信号能快速灵敏地反映植物生理状态及其与环境的关系,是一种理想光系统探针。测定了深圳市7种园林植物叶片的叶绿素荧光参数和叶绿素含量,并对这些生理参数与大气污染物SO₂的相关性进行了分析。结果表明,7种植物叶片的叶绿素含量具有明显的种间差别,生境的差别远小于种间差别。所测定的7种园林植物的F_v/F_m相差不大,平均为0.78,低于理想条件下的最大值,说明存在一定的生长胁迫。叶绿素荧光的光化学淬灭qP的种间差别不明显。非光化学猝灭系数qN的种类差别较大,白兰Michelia alba和短穗鱼尾葵Caryota mitis具有较高的非光化学淬灭能力,说明这两个种具有一定的光保护能力。7种植物中,白兰的ΦpsⅡ要明显地较低于其它植物。深圳大气污染对城区植物的生理生化特性尚未构成不良影响,在深圳市区的环境中,短穗鱼尾葵、勒杜鹃Bougainvillea spectabilis和阴香Cinnamomum burmanii的叶绿素荧光参数可以作为大气污染物的指示指标;大红花Hibiscus rosa-sinensis、九里香Murraga paniculata、白兰和黄叶假连翘Duranta cv Golden Leaves具有相对较高抗污染物的能力。植物的叶绿素荧光参数也在一定程度上受到叶绿素的影响,阴香、短穗鱼尾葵、大红花和九里香的部分叶绿素荧光参数与植物叶片叶绿素含量呈正相关。     

蚕豆监测大气SO2污染的指标筛选研究

熏气和暴露试验表明,蚕豆叶片可见伤害症状不宜作为监测指标,超氧化物歧化酶（ＳＯＤ）活性、抗坏血酸（ＡＳＡ）含量和游离氨基酸（ＡＡ）含量作为监测指标,其指示效果优于过氧化物酶（ＰＯＤ）活性和叶绿素含量,其中又以ＳＯＤ活性为最好,而根据以上５个指标综合评价的效果又要优于任何单个指标．     

杜鹃对SO2胁迫的抗氧化防护效应

以SO2耐受性植物杜鹃(Rhododendron sp.)为材料,在2个高浓度SO2熏气后,检测了叶组织中丙二醛(MDA)、可溶性蛋白和叶绿素含量以及抗氧化酶活性.结果表明:40和80mg?m-3SO2熏气4h(1d)后,杜鹃叶片超氧化物歧化酶(SOD)活性和MDA含量均分别比对照显著增加了11.26%、11.86%和73.32%、76.43%;随熏气时间的延长,SOD、过氧化物酶(POD)、过氧化氢酶(CAT)活性持续增高,且SOD和CAT活性显著高于对照,MDA含量逐渐降至对照水平;SO2熏气导致叶片可溶性蛋白含量显著降低,但叶绿素含量却无显著改变.熏气后恢复期间,抗氧化酶活性相对降低,可溶性蛋白含量恢复至对照水平.研究发现,杜鹃对SO2的耐受性与细胞中抗氧化酶活性的诱导性增强有关,抗氧化能力增强是植物适应SO2胁迫的重要原因.     

Cd、Zn复合污染对水车前叶绿素含量和活性氧清除系统的影响

主要研究了重金属Cd、Zn单一及复合污染对水车前叶绿素含量和活性氧清除系统的影响。超氧化物歧化酶 (SOD)、过氧化物酶 (POD)、过氧化氢酶 (CAT)活性都在 0 1mg·L-1Cd处理浓度时达到峰值 ,随培养浓度的增加 ,活性下降。叶绿素含量则随处理的浓度的上升而呈递减趋势。在各Cd处理梯度中加入Zn后 ,随加入Zn浓度的增大 ,上述各指标与单一Cd处理差异显著性增强 ,表明Zn增强了Cd的毒害作用 ,显示出协同作用的趋势     

旅游和工业化对亚热带森林地区大气环境质量及两种木本植物叶绿素荧光特性的影响

研究了旅游、工业化等不同类型的人类活动对亚热带森林大气ＣＯ２、ＳＯ２、ＮＯｘ浓度及两种木本植物———木荷（ＳｃｈｉｍａｓｕｐｅｒｂａＧａｒｄｎ．ｅｔＣｈａｍｐ．）和马尾松（ＰｉｎｕｓｍａｓｏｎｉａｎａＬａｍｂ．）叶绿素荧光特性的影响。结果表明,不同形式人类活动使森林中大气ＣＯ２浓度上升了１７～３０μｍｏｌ·ｍｏｌ－１,ＮＯｘ化合物的浓度上升了５～２０ｎｍｏｌ·ｍｏｌ－１,ＳＯ２浓度上升了２～１９ｎｍｏｌ·ｍｏｌ－１。森林大气中ＣＯ２、ＮＯｘ、ＳＯ２浓度随着人类活动的加强而升高。木荷和马尾松叶片Ｆｖ／Ｆｍ、ΦＰＳⅡ和稳态下的ｑＰ随人类活动加强而下降,其下降趋势与ＣＯ２、ＳＯ２、ＮＯｘ的上升趋势相一致。     

二氧化硫污染对植物影响的研究进展

20多年来 ,关于SO2 污染对植物伤害症状、生长发育、生理生化的影响以及伤害机理的研究获得了长足的发展。研究成果应用于大气SO2 的监测和评价 ,以及抗污树种的筛选。对目前刚开始的SO2 与NOx、O3 等复合污染和酸沉降对植物影响的研究 ,将会成为今后研究的主导方向。     

叶绿素含量测定的简化

本文介绍一种避免称重、研磨、冲洗和过滤等繁琐步骤,仅将确定面积的叶片细丝用少量80%丙酮浸泡提取后便可比色计算的简便的测定叶绿素含量的方法。此法省时间、省溶剂,不受叶片含水量变化的干扰,适合于大批量叶片样品的测定,而且便于与以单位叶面积表示的光合速率联系起来分析实验结果。同时,指出一些可能影响测定结果的因素。     

基于叶绿素荧光参数的小麦叶片叶绿素相对含量估算方法

叶绿素含量是植物学和农业相关研究领域常用的生理指标.叶绿素含量和叶片光合功能密切相关,但是现有的叶绿素含量的测定方法无法实现叶绿素含量和光合功能的同步测定和关联分析.为解决该问题,本研究通过测定35个小麦品种旗叶的SPAD值和叶绿素荧光诱导动力学曲线,分别使用不同时间的快速叶绿素荧光动力学曲线的荧光值,以及33个常用荧...     

Rapid,nondestructive measurement of chlorophyll content in leaves with nonuniform chlorophyll distribution

A practical microcomputerized video image analysis method is described for quantifying leaf chlorophyll content without extraction. Chlorophyll concentration is estimated from densimetric measurements of whole, intact leaves. Direct comparison with conventional extraction measurements on Epipremnum aureum, a variegated species, verified the image analysis technique's accuracy. The inherent advantages with regard to the nondestructive and convenient nature of the measurement, and suitability for leaves with irregular chlorophyll distribution, are discussed.     

The chlorophyll fluorescence ratio F690/F730 in leaves of different chlorophyll content

The red laser-induced chlorophyll-fluorescence induction kinetics of predarkened leaf samples were registered simultaneously in the 690 and 730 nm regions i.e., in the region of the two chlorophyll fluorescence emission maxima. From the induction kinetics the chlorophyll fluorescence ratio F690/F730 was calculated. The ratio F690/F730 shows to be dependent on the chlorophyll content of leaves. It is significantly higher in needles of damaged spruces (values of 0.45–0.9) than in normal green needles of healthy trees (values of 0.35–0.5). During development and greening of maple leaves the ratio F690/F730 decreases with increasing chlorophyll content. Determination of the ratio F690/F730 can be a suitable method of monitoring changes in chlorophyll content in a non-destructive way in the same leaves during development or the yellowish-green discolouration of needles of damaged spruces in the Black Forest with the typical tree decline symptoms.Abbreviations F690/F730 ratio of the fluorescence yield at the two fluorescence-emission maxima in the 690 and 730 nm regions - F_m maximum fluorescence - F_s steady-state fluorescence     

硫对烟草叶片光合特性和叶绿素荧光参数的影响

通过液培试验,测定了不同硫营养水平(0～32 mmol/L)下烟草叶片的叶绿素含量、气体交换参数和叶绿素荧光参数.结果表明,随着硫浓度的升高,烟草叶片的Chl.a、Chl.b、总Chl的含量和Chl.a/b逐渐增加;类胡萝卜素呈先下降后升高的趋势;烟草叶片的净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)、胞间CO2浓度(Ci)下降显著,气孔限制值(Ls)明显升高,这表明高硫对烟草叶片的气体交换参数影响较大.随着硫浓度的升高,烟草叶片光合有效量子产量(EQY)、光合电子传递速率(ETR)、光化学淬灭(qP)都表现为先升高后降低,一般是4 mmol/L和8 mmol/L处理相对较高,浓度超过8 mmol/L以后,以上参数显著下降.非光化学淬灭(NPQ) 0,16 mmol/L和32 mmol/L处理表现相对较高,2、4、8 mmol/L处理的相对较低,2～8 mmol/L浓度的处理最适宜烟草的生长,高硫或低硫都会导致烟草EQY、ETR、qP降低和NPQ的升高.     

The turnover of chlorophyll in greening wheat leaves

A method for the estimation of chlorophyll turnover in wheat leaves is presented. This is based on the inhibition of chlorophyll synthesis by treatment of the cut leaves with laevulinic acid (LA), a competitive inhibitor of δ-aminolaevulinic acid dehydratase. The turnover of chlorophyll in young, greening leaves, given short periods of light was a relatively rapid process. However, in seedlings exposed to light for longer periods the turnover became progressively slower, and was measured in days rather than hours.     

Chloroplast-ultrastructure and chlorophyll content in leaves from Quercus branches with and without epiphytic lichen thalli

Abstract The effect that the massive presence of lichen thalli growing on the branches of Quercus pyrenaica and Q. rotundifolia leaves has on their chloroplasts been studied. In both species there were significant decreases in the amount of chlorophylls in the leaves of twigs with a dense cover of lichens in comparison with the leaves from thallus-free twigs. The areas and perimeter of chloroplasts in leaves from twigs with epiphytes did not differ significantly from those in leaves without epiphytes. However, in leaves with epiphytes the percentage of chloroplast area occupied by starch was higher. In Q. pyrenaica the number of grana per chloroplast section and per μm², the percentage of chloroplast stroma occupied by grana, the average number of thylakoids forming grana and the grana width was significantly smaller in leaves near lichen populations. These results are discussed and related to the great chelating capacity of the lichen's substances.     

缺硫对脐橙叶片光合特性和叶绿素荧光参数的影响

采用营养液培养的方法,对缺硫脐橙叶片的光合特性进行了研究。结果表明,在缺硫情况下,脐橙叶片的净光合速率(Pn)、光呼吸速率(Pr)、光合色素含量、可溶性蛋白质含量、初始荧光(Fo)、光化学效率(Fv/Fm)、最大荧光(Fm)和电子传递速率(ETR)显著下降,而光呼吸/光合比(Pr/Pn)显著升高。缺硫脐橙植株的光合能力降低,可能是叶绿体发育不全或特性功能蛋白含量不足所致。     

The effect of chlorophyll content on changes of photochemical reactions in intact kidney bean leaves

Abstract. Activation spectra of photochemical reactions were measured by a flash spectrophotometer in leaves having varying chlorophyll contents at different stages of greening. The increase of chlorophyll concentration up to 30 nmol cm^-2 elevated the rates of photochemical reactions at all wavelengths of light used, and was found to be produced by an increase in the amounts of reaction centres. Further accumulation of chlorophyll up to 40 nmol cm^-2 was associated with an increase in light-harvesting chlorophyll, an improved rate of photochemical reactions around 600 nm and at 700 nm, and self-absorption and screening effects where chlorophyll absorbed maximally (400–450 nm and around 680 nm).     

Involvement of Arabidopsis glutaredoxin S14 in the maintenance of chlorophyll content

Plant class‐II glutaredoxins (GRXs) are oxidoreductases carrying a CGFS active site signature and are able to bind iron–sulfur clusters in vitro. In order to explore the physiological functions of the 2 plastidial class‐II isoforms, GRXS14 and GRXS16, we generated knockdown and overexpression Arabidopsis thaliana lines and characterized their phenotypes using physiological and biochemical approaches. Plants deficient in one GRX did not display any growth defect, whereas the growth of plants lacking both was slowed. Plants overexpressing GRXS14 exhibited reduced chlorophyll content in control, high‐light, and high‐salt conditions. However, when exposed to prolonged darkness, plants lacking GRXS14 showed accelerated chlorophyll loss compared to wild‐type and overexpression lines. We observed that the GRXS14 abundance and the proportion of reduced form were modified in wild type upon darkness and high salt. The dark treatment also resulted in decreased abundance of proteins involved in the maturation of iron–sulfur proteins. We propose that the phenotype of GRXS14‐modified lines results from its participation in the control of chlorophyll content in relation with light and osmotic conditions, possibly through a dual action in regulating the redox status of biosynthetic enzymes and contributing to the biogenesis of iron–sulfur clusters, which are essential cofactors in chlorophyll metabolism.     

Evaluation of reflectance spectroscopy indices for estimation of chlorophyll content in leaves of a tropical tree species

The effectiveness of eight spectral reflectance indices for estimating chlorophyll (Chl) content in leaves of Eugenia uniflora L., a tropical tree species widely distributed throughout the world and a key species for ecosystem restoration projects, was evaluated. Spectral reflectance indices were tested using sun and shade leaves with a broad variation in leaf mass per area (LMA). Shortly after plants were exposed to chilling temperatures, there was a dramatic visible change in some sun leaves from green to red. Prior to testing Chl-related reflectance indices, the green and red leaves were separated according to the anthocyanin reflectance index (ARI). Slightly green to dark green leaves corresponded to an ARI value less than 0.11 (n = 107), whereas slightly red to red leaves corresponded to an ARI value greater than 0.11 (n = 35). To estimate leaf Chl, two simple reflectance indices (SR₆₈₀ and SR₇₀₅), two normalized difference indices (ND₆₈₀ and ND₇₀₅), two modified reflectance indices (mSR₇₀₅ and mND705), a modified Chl absorption ratio index (mCARI₇₀₅) and an index insensitive to the presence of anthocyanins (CI_re) were evaluated. Good estimates of leaf Chl content were obtained using the reflectance indices tested regardless of the presence of anthocyanins and changes in LMA. Based on the coefficients of determination (r ²) and the root mean square errors (RMS?_c) the best results were obtained with reflectance indices measured at wavelengths of 750 and 705 nm. Considering the performance of the models the best reflectance indices to estimate Chl contents in E. uniflora leaves with a broad variation in LMA and anthocyanin contents was SR₇₀₅ and mCARI₇₀₅.