CO2浓度倍增对几种植物叶片的叶绿素蛋白质复合物的影响

研究了CO_2浓度倍增对大豆(Glycine max L.,C_3植物)、黄瓜(Cucumis sativus L.,C_3植物)、谷子(Setaria italica (L.) Beauv.,一种不很典型的C_4植物)和玉米(Zea mays L.,C_4植物)叶片的叶绿素蛋白质复合物的影响。实验植物盆栽于聚乙烯薄膜(或玻璃)的开顶式培养室中。播种后对照室的CO_2浓度立即保持在大气浓度(350±10)×10~(-6)中,CO_2浓度倍增处理室则保持在(700±10)×10~(-6)下。研究结果表明,对于大豆、黄瓜和谷子,CO_2浓度倍增均使其PSⅡ捕光叶绿素a/b-蛋白质复合物(LHCⅡ)的聚合体态的量增多,单体态的量减少。但C_4植物玉米对CO_2浓度倍增没有这样的反应。作者认为在大豆等植物中,LHCⅡ的上述状态变化可能是植物的光合机构对长期高CO_2浓度的一种适应效应,这样能提高光合作用中光能的吸收、传递和转换的效率,并支持高效的光合碳素同化作用。     

饱和白光引起的光系统Ⅱ捕光复合体（LHCⅡ）从反应中心复合体脱离不同于弱红光引起的状态1向状态2的转换

我们观测了不同光照预处理对拟南芥、小麦和大豆叶片光合作用和低温（77K）叶绿素荧光参数F685、F735和F685／F735的影响。野生型拟南芥叶片光合作用对饱和光到有限光转变的响应曲线是V型,而缺乏叶绿体蛋白激酶的突变体STN7的这一曲线为L型。饱和白光可以引起拟南芥叶片F685／F735的明显降低,但是F735没有明显增高,而弱红光可以导致拟南芥叶片F685／F735的明显降低和F735的明显增高,表明弱红光可以引起状态1向状态2的转变,同时伴随从光系统Ⅱ脱离的LHCⅡ与光系统Ⅰ的结合,而饱和白光只能引起LHCⅡ从光系统Ⅱ反应中心复合体脱离。并且,低温叶绿素荧光分析结果证明,饱和白光可以引起大豆叶片LHCⅡ脱离,但是不能引起小麦叶片LHCⅡ脱离,而弱红光可以引起小麦叶片的这种状态转换,却不能引起大豆叶片的这种状态转换。因此,饱和白光引起的野生型拟南芥和大豆叶片的LHCⅡ脱离不是一个典型的状态转换现象。     

Effects of Doubled CO2 on Contents of Photosynthetic and on Kinetic Parameters of Fluorescence Induction in Different Genotypes of Soybean

Effects of doubled C02 on photosynthetic characteristics of soybean ( Glycine max L. ) Bragg (wild type) and its different monogene mutation strains--Nts 382 (supemodulation mutant) and Nod 49 (non-nodulation mutant) were studied. The experimental results showed that the contents of chlorophyll and carotenoid of Bragg, Nts 382 and Nod 49 were increased under doubled CO2, respectively, although to different extent. The determination results of fluorescence induction kinetic parameters showed that PS Ⅱ activity, the efficiency of primary conversion of light energy of PS Ⅱ and the efficiency of potential photosynthetic quantum conversion of a leaf from Bragg and its mutants were raised in doubled CO2. Fluorescence photochemical quenching coefficient and the overall photochemical quantum yield of PS Ⅱ were raised and non-photochemical quenching coefficient was reduced with CO2 enrichment; such changes were bigger in Nts 382 than those in Bragg and Ned 49. It might be that atmospheric N2 was more effectively utilized by Nts 382 than by Bragg and Ned 49.     

Effects of Doubled CO2 Concentration on the Content of Photosynthetic Pigments and PS II Functions of Jointing and Grouting in Setaria italica

Effects of doubled CO2 on the contents of chlorophyll and carotenoid per unit fresh weight and per unit area of leaves and PS Ⅱ functions of Setaria italica (L.) Beauv. were studied. The experimental results showed that the contents of chlorophyll and carotenoid, the proportion of opened PS Ⅱ reaction center from the mature leaves at jointing stage and the mature flag leaves at grouting stage were raised with CO2 enrichment. However, qN value and the overall photochemical quantum yield of PS Ⅱ , as well as the Fv/Fo, Fv/Fro and Fd/Fs in the above-mentioned leaves both at the jointing and grouting stage in response to doubled CO2 were different. The final outcome showed that the photosynthetic functions from the leaves at jointing stage improved by doubled CO2 were better than those from the flag leaves at grouting stage.     

Effects of Water Stress on Chlorophyll-Protein Complexes in Wheat Chloroplasts

The excitation energy transfer from light harvesting chlorophyll protein complexes to PS Ⅱ was inhibited under water stress. The contents of iriternal antennae chlorophyll-protein complexes of PS Ⅱ (CPa), light harvesting chlorophyll-protein complexes of PS Ⅱ (LHC Ⅱ ), light harvesting chlorophyll-protein of PS Ⅰ (LHC Ⅰ ) and chlorophyll a protein complex of reaction center of PS Ⅰ were decreased by water stress. The decrease of chlorophyll-protein complexes of PS Ⅱ was greater than that of PS Ⅰ . It was indicated that the amount of 25 kD polypeptide of LHC Ⅱ in particular, as well as that of 43 and 47 kD polypeptides of CPa, and 21 kD polypeptide of LHC Ⅰ , were reduced by water stress.     

Effect of Doubled-CO2 Concentration on the Ultrastructure of Chloroplasts from Medicago sativa and Setaria italica

It has been reported in quite a number of literatures that doubled CO2 concentration increased the photosynthetic rate and dry matter production of C3 plants, but substantially affected C4 plants little. However, why may CO2 enrichment promote growth and either no change or decrease reproductive allocation of the C3 species, but havinag no effects on growth characteristics of the C4 plants? So far, there has been no satisfactory explanation on that mentioned above, except the differences in their CO2 compensatory points. In the past, although some studies on ultrastructure of the chloroplasts under doubled CO2 concentration were limitedly conducted. Almost all the relevant experimental materials were only from C3 plants not from C4 plants, and even though the results were of inconsistancy. Thereby, it needs to verify whether the differences in photosynthesis of C3 and C4 plants at doubled CO2 level is caused by the difference in their chloroplast deterioration. Experiments to this subject were conducted at the Botanical Garden of Institute of Botany, Academia Sinica in 1993 and 1994. Both experimental materials from C3 plant alfalfa (Medicago sativa) and C4 plant foxtail millet (Setaria italica) were cultivated in the cylindrical open-top chambers (2.2 m in diameter × 2.4 m in height) with aluminum frames covered by polyethylene film. Natural air or air with 350× 10-6 CO2 were blown from the bottom of the chamber space with constant temperature between inside and outside of the chamber 〈0.2℃〉. Electron microscopic observation revealed that the ultrastructure of the chloroplasts from C3 plant Medicago sativa and C4 plant Seteria italica growing under the same doubled CO2 concentration were quite different from each other. The differential characteristics in ultrastructure of chloro plasts displayed mainly in the configuration of thylakoid membrances and the accumulation of starch grains. They were as follows: 1. The most striking feature was the building up of starch grains in the chloroplasts of the bundle sheath cells (BSCs) and the mesophyll cells (MCs) at doubled CO2 concentra tion. The starch grains appeared centrifugally first in the BSCs and then in the chloroplast of the other MCs. It was worthy to note that the starch grains in the chloroplasts of C4 plant Setaria ira/ica were much more than those of the C3 plant Medicago sativa . The decline of photosynthesis in the doubled CO2-grown C4 plants might be caused by an over accumulation of starch grains, that deformed the chloroplast even demaged the stroma thylakoids and grana. There might exsist a correlation between the comformation of thylakoid system and starch grain accumulation, namely conversion and transfer of starch need energy from ATP, and coupling factor (CF) for ATP formation distributed mainly on protoplastic surface (PSu) of stroma thylakoid membranes, as well as end and margin membranes of grana thylakoids. Thereby, these results could provide a conclusive evidence for the reason of non effectiveness on growth characteristics of C4 plant. 2. Under normal condition , the mature chlolroplats of higher plants usually develop complete and regularly arranged photosynthetic membrane systems . Chloroplasts from the C4 plant Setaria italica, however, exerted significant changes on stacking degree, grana width and stroma thylakoid length under doubled CO2 concentration; In these changes, the grana stacks were smaller and more numerous, and the number of thylakoids per granum was greatly increased, and the stroma thylakoid was greatly lengthened as compared to those of the control chloroplasts. But the grana were mutually intertwined by stroma thylakoid. The integrity of some of the grana were damaged due to the augmentation of the intrathylakoid space . Similarly, the stroma thylakoids were also expanded. In case. the plant was seriously effected by doubled CO2 concentration as observed in C4 plant Setaria italica , its chloroplasts contained merely the stroma (matrix) with abundant starch grains, while grana and stroma thylakoid membranes were unrecognizable, or occasionally a few residuous pieces of thylakoid membranes could be visualized, leaving a situation which appeared likely to be chloroplast deterioration. However, under the same condition the C3 plant Medicago sativa possessed normally developed chloroplasts, with intact grana and stroma thylakoid membranes. Its chloroplasts contained grana intertwined with stroma thylakoid membranes, and increased in stacking degree and granum width, in spite of more accumulated starch grains within the chloroplasts. These configuration changes of the thylakoid system were in consistant with the results of the authors another study on chloroplast function, viz. the increased capacity of chloroplasts for light absorption and efficiency of PSⅡ.     

Influence of Doubled CO2 on Plant Growth and Soil Microbial Biomass C and N

Salix babylonica L., Triticum aestivum L., Chenopodium album L. and Amaranthus cruemus L. were grown in the N-deficient soil in open-top chambers blown with ambient or doubled ambient CO2 air, and their growth was measured. Soil samples were collected to assess the influence of doubled CO2 on the soil microbial biomass C (Cmic) and N (Nmic). Results showed that the biomass of shoot and root was increased by doubled CO2 in the four species of plants. Doubled CO2 increased Cmic in S. babylonica and decreased Cmic in T. aestivum and C. album. On the other hand, Nmic in three species except T. aestivum was stimulated by doubled CO2. Doubled CO2 had no significant effect on Cmic in A. cruentus and Nmic in T. aestivum. However, the ratios of Cmic- to -Nmic of all four species were consistently declined under doubled CO2 treatment. It implies that CO2 enrichment may have positive influence on the quality of organic matter of N-low soil in global change.     

Energy transfer for low temperature fluorescence in PS II mutant thylakoids

The Chl-protein complexes of three maize (Zea mays L.) mutants and one barley (Hordeum vulgare L.) mutant were analyzed using low temperature Chl fluorescence emissions spectroscopy and LDS-polyacrylamide gel electrophoresis. The maize mutants hcf-3, hcf-19, and hcf-114 all exhibited a high Chl fluorescence (hcf) phenotype indicating a disruption of the energy transfer within the photosynthetic apparatus. The mutations in each of these maize mutants affects Photosystem II. The barley mutant analyzed was the well characterized Chl b-less mutant chlorina-f2, which did not exhibit the hcf phenotype. Chlorina-f2 was used because no complete Chl b-less mutant of maize is available. Analysis of hcf-3, hcf-19, and hcf-114 revealed that in the absence of CP43, LHC II can still transfer excitation energy to CP47. These results suggest that in mutant membranes LHC II can interact with CP47 as well as CP43. This functional interaction of LHC II with CP47 may only occur in the absence of CP43, however, it is possible that LHC II is positioned in the thylakoid membranes in a manner which allows association with both CP43 and CP47.Abbreviations hcf high chlorophyll fluorescence - LDS lithium dodecyl sulfate - LHC II light-harvesting complex of Photosystem II - LHC I light-harvesting complex of Photosystem I - CPIa chlorophyll-protein complex consisting of LHC I and the PS I core complex - CPI chlorophyll-protein complex consisting of the PS I core complex - CP47 47 kDa chlorophyll-protein of the Photosystem II core - CP43 43 kDa chlorophyll-protein of the Photosystem II core - CP29 29 kDa chlorophyll-protein of Photosystem II - CP26 26 kDa chlorophyll-protein of Photosystem II - CP24 24 kDa chlorophyll-protein of Photosystem II - fp free pigments     

Light stress photodynamics of chlorophyll-binding proteins in Arabidopsis thaliana thylakoid membranes revealed by high-resolution mass spectrometric studies

In higher plants the light energy is captured by the photosynthetic pigments that are bound to photosystem I and II and their light-harvesting complex (LHC) subunits. In this study, we examined the photodynamic changes within chlorophyll-protein complexes in the thylakoid membrane of Arabidopsis thaliana leaves adapted to low light and subsequently exposed to light stress. Chlorophyll-protein complexes were isolated using sucrose density gradient centrifugation and blue-native polyacrylamid gel electrophoresis (BN-PAGE). Proteome analysis was performed using SDS-PAGE, HPLC and high resolution mass spectrometry. We identified several rarely expressed and stress-induced chlorophyll-binding proteins, showed changes in localization of early light-induced protein family and LHC protein family members between different photosynthetic complexes and assembled/disassembled subcomplexes under light stress conditions and discuss their role in a variety of light stress-related processes.     

A Circular Dichroism Spectroscopic Study Revealing the Cause of the Changes of Chlorophyll a Fluorescence Induction of Photosystem Ⅱ During Heat Treatment

Chlorophyll a fluorescence and circular dichroism (CD) spectra of photosystem Ⅱ (PSⅡ) membrane were measured after heat treatment. The chlorophyll fluorescence parameter Fo' remained stable after treatment at the temperatures from 30 ℃ to 40 ℃ and then reached a maximum after treatment at 55 ℃. In PSⅡ membranes and LHCⅡ (light-harvesting chlorophyll a/b binding complex)-enriched complexes, anomalous CD signals with extremely large amplitudes occurred during the heat treatment. The temperature corresponding to the maximum anomalous CD intensity peaking at 677 nm was 40 ℃. The results indicate that the aggregation state of the LHCⅡ in PSⅡ is related to the anomalous CD signal, and can be an important factor influencing Fo' in the heat treatment of PSⅡ membrane.     

管藻目绿藻叶绿素蛋白复合物特性及比较研究

By mild PAGE method, 11, 11, 7 and 9 chlorophyll-protein complexes were isolated from two species of siphonous green algae (Codium fragile (Sur.) Hariot and Bryopsis corticulans Setch.), green alga (Ulothrix flacca (Dillw.) Thur.), and spinach (Spinacia oleracea Mill.), respectively. Apparent molecular weights, Chl a/b ratios, distribution of chlorophyll, absorption spectra, low temperature fluorescence spectra of these complexes were determined, and compared with one another. PSⅠ complexes of two siphonous green algae are larger in apparent molecular weight because of the attachment of relative highly aggregated LHCⅠ. Four isolated light-harvesting complexes of PSⅡ are all siphonaxanthin-Chl a/b-protein complexes, and they are not monomers and oligomers like those in higher plants. Especially, the absence of 730 nm fluorescence in PSⅠ complexes indicates a distinct structure and energy transfer pattern.     

CO_2倍增对植物生长和土壤微生物生物量碳、氮的影响

关于大气ＣＯ２浓度倍增（即为７００μｍｏｌＣＯ２·ｍｏｌ－１空气）将对植物生长产生诸多影响,已有大量报道［１,２］。但ＣＯ２倍增对植物及所在土壤中微生物影响的研究甚少［３,４］。土壤微生物是陆地生态系统中最活跃的成分,担负着分解动植物残体的重要作用,...     

Characterization of photosystem I antenna proteins in the prasinophyte Ostreococcus tauri

Prasinophyceae are a broad class of early-branching eukaryotic green algae. These picophytoplankton are found ubiquitously throughout the ocean and contribute considerably to global carbon-fixation. Ostreococcus tauri, as the first sequenced prasinophyte, is a model species for studying the functional evolution of light-harvesting systems in photosynthetic eukaryotes. In this study we isolated and characterized O. tauri pigment-protein complexes. Two photosystem I (PSI) fractions were obtained by sucrose density gradient centrifugation in addition to free light-harvesting complex (LHC) fraction and photosystem II (PSII) core fractions. The smaller PSI fraction contains the PSI core proteins, LHCI, which are conserved in all green plants, Lhcp1, a prasinophyte-specific LHC protein, and the minor, monomeric LHCII proteins CP26 and CP29. The larger PSI fraction contained the same antenna proteins as the smaller, with the addition of Lhca6 and Lhcp2, and a 30% larger absorption cross-section. When O. tauri was grown under high-light conditions, only the smaller PSI fraction was present. The two PSI preparations were also found to be devoid of the far-red chlorophyll fluorescence (715-730 nm), a signature of PSI in oxygenic phototrophs. These unique features of O. tauri PSI may reflect primitive light-harvesting systems in green plants and their adaptation to marine ecosystems. Possible implications for the evolution of the LHC-superfamily in photosynthetic eukaryotes are discussed.     

Characterization of a New Chlorophyll-Protein Complex and Studies on Some Properties of Other Chlorophyll-Containing Bands

1. The chlorophyll-protein complexes of sun plant spinach and shade plants Malaxis monophyllos (L.) Sw. and Chlorophytum comosum (Thunb.) Jacques were resolved by SDS-PAGE at lower temperature (2—4 ℃). Besides 8 chlorophyll-containing bands Ⅰa, Ⅰb, Ⅰc, Ⅱa, Ⅱb, Ⅱc, Ⅲ and Ⅳ mentioned in our previous paper (Chu et al., 1980), three more small chlorophyll-containing bands were also observed. Among these small bands Ⅱa which often appeared between Ⅰc and Ⅱa looked like a oligomer of LHCP complex according to its properties in colour, absorption spectrum and fluorescence emission etc. 2. When electrophoresis was carried out at lower temperature (2—4 ℃), the quantity of free pigments (Ⅲ) was obviously lower, while the relative quantities of LHCP Ⅱa, Ⅱb and PS Ⅱ’s band (Ⅳ) were apparently higher than those carried out at higher temperature (12—15 ℃). At lower temperature three bands of Ⅰ could be resolved in shade plants M. monophyllos and C. comosum, and at higher temperature there was only one band of Ⅰ (Ⅰc). But at higher temperature three bands of Ⅰ could be resolved in sunflower. 3. The percentage of LHCP complexes of shade plant M. monophyllos in total amount of chlorophyll (57%) was obviously higher than that of sun plant spinach (43%). The percentage of complexes Ⅰ of sun plant spinach in amount of total chlorophyll (27%) was obviously higher than that of shade plant M. monophyllos (14%). The relative quantity among three bands of Ⅰ in different Plants is different. 4. The chl a/b ratio of LHCP bands of shade plants were lower than that of corresponding bands of sun plants. The chl a/b ratio of Ⅱa of M. monophyllos was 1.1, Ⅱc, 1.2; but that of Ⅱa of spinach was 1.4, Ⅱc, 1.66.     

Species-related differences in the electrophoretic behavior of CP 29 and CP 26: An immunochemical analysis

The monomeric chlorophyll-protein complexes, CP 29 and CP 26 seen in the Camm and Green (1980) and Dunahay and Staehelin (1986) green gels do not always migrate in the order of the apparent molecular weight of their apoproteins as determined by denaturing gel electrophoresis. In barley and corn they do, but in spinach they do not. In addition, in some higher plant species these chlorophyll-protein complexes comigrate on green gels causing confusion in the literature. To remedy this situation and circumvent future confusion, we propose that the CP 29 and CP 26 complexes be named according to the relative molecular weight of their apoproteins on denaturing gels. Our proposal is supported by the results obtained from four antibodies used on Western blot samples of whole thylakoids, grana membranes, and PS II preparations from different plants. The higher molecular weight proteins (proposed CP 29's) react strongly to one set of antibodies, and the lower molecular weight proteins (proposed CP 26's) react strongly to a different set. In spinach, CP 26 antibodies react also with CP 29, but the extent of the cross-reactivity depends critically on the gel electrophoresis system used. Accordingly, a lack of antibody reactivity under certain conditions may not indicate two proteins are unrelated, just simply that a particular epitope is no longer accessible following gel electrophoresis with a particular buffer system.Abbreviations CP Chlorophyll-protein - ammediol 1,2, amino-methyl-propanediol - Tris tris(hydroxymethyl)aminomethane - TBS Tris-buffered saline - MES 2-[N-Morpholino]ethane sulfonic acid - PS II Photosystem II - LHC II light harvesting polypeptides of PS II - BBY stacked membrane preparation of Berthold, Babcock and Yocum - HRP horseradish peroxidase - AP alkaline phosphatase - PVDF polyvinylidene fluoride - BSA bovine serum albumin - KLH keyhole limpet hemocyanin     

Respective and interactive effects of doubled CO2 and O3 concentration on membrane lipid peroxidation and antioxidative ability of soybean

Effects of doubled CO2 and O3 concentration on Soybean were studied in open-top chambers (OTC). Under doubled CO2 concentration, grain yield and biomass increased, the SOD activity, vitamin C (Vc) and carotenoid (Car) content also increased; Superoxide (O2-) generating rate decreased, relative conductivity and malondialdehyde (MDA) content significantly declined. But under doubled O3 concentration, the SOD activity, Vc and Car contents declined, resulting in imbalance of activated-oxygen production, enhanced O2- generating rate and accelerated process of lipid peroxidation and increase in MDA content and ion leakage of leaves. The final result was decreased grain yield and plant biomass. Interactive effects of doubled CO2 and O3 concentrations on soybean were mostly counteractive. However, the beneficial effects of concentration-doubled CO2 are more than compensate the negative effects imposed by doubled O3, and the latter in its turn partly counteracted the positive effects of the former.     

Effect of CO2 Concentration Doubling on the Leaf Morphology and Structure of 10 Species in Gramineae

The effects of CO2 concentration on leaf thickness, chloroplast manbers in the bundle sheath cell, epidermal cell density, stomatal density, stomatal index, stomatal size were compared in 10 species in Gramineae: Triticum aestivum L., T. aestivum ssp. tibeticum, Hordeum vulgare L., H. brevisubulatum ( Trin. ) Link, Oryza sativa L., O. meyeriana ssp. granulata, Setaria italica (L.) Beauv, S. viridis (L.) Beauv, Sorghum vulgare Pers., Zea mays L. following their exposure to doubled carbon dioxide (700μL/L) and ambient carbon dioxide concentration (350μL/L). The results indicated that different species of plants might vary in their response to doubled CO2. In general, the leaves became thicker under the elevated CO2 condition. The mean stomatal density of the C3 species was decreased in doubled CO2, whereas the results of C4 species showed an inverse trend. The epidermal cell density and the chloroplast numbers of the bundle sheath cell in the wild plant species were less than those in the control under CO2 enrichment. The stomatal density was positively correlated with the stomatal index. Finally, the general pattern of structural variation under different CO2 concentrations was proposed, and their implication to the research of global change was discussed as well.     

Respective and interactive effects of doubled CO2 and O3 concentration on membrane lipid peroxidation and antioxidative ability of soybean

Effects of doubled CO2 and O3 concentration on Soybean were studied in open-top chambers (OTC). Under doubled CO2 concentration, grain yield and biomass increased, the SOD activity, vitamin C (Vc) and carotenoid (Car) content also increased; Superoxide (O2-.) generating rate decreased, relative conductivity and malondialdehyde (MDA) content significantly declined.But under doubled O3 concentration, the SOD activity, Vc and Car contents declined, resulting in imbalance of activated-oxygen production, enhanced O2-. generating rate and accelerated process of lipid peroxidation and increase in MDA content and ion leakage of leaves. The final result was decreased grain yield and plant biomass. Interactive effects of doubled CO2 and O3 concentrations on soybean were mostly counteractive. However, the beneficial effects of concentration-doubled CO2 are more than compensate the negative effects imposed by doubled O3, and the latter in its turn partly counteracted the positive effects of the former.     

饱和白光引起的光系统II捕光复合体(LHCII)从反应中心复合体脱离不同于弱红光引起的状态1向状态2的转换

我们观测了不同光照预处理对拟南芥、小麦和大豆叶片光合作用和低温(77K) 叶绿素荧光参数F685、F735和F685/F735的影响.野生型拟南芥叶片光合作用对饱和光到有限光转变的响应曲线是V型,而缺乏叶绿体蛋白激酶的突变体STN7的这一曲线为L型. 饱和白光可以引起拟南芥叶片F685/F735的明显降低,但是F735没有明显增高,而弱红光可以导致拟南芥叶片F685/F735的明显降低和F735的明显增高,表明弱红光可以引起状态1向状态2的转变,同时伴随从光系统II脱离的LHC II与光系统I的结合,而饱和白光只能引起LHC II从光系统II反应中心复合体脱离.并且,低温叶绿素荧光分析结果证明,饱和白光可以引起大豆叶片LHC II脱离,但是不能引起小麦叶片LHC II脱离,而弱红光可以引起小麦叶片的这种状态转换,却不能引起大豆叶片的这种状态转换.因此,饱和白光引起的野生型拟南芥和大豆叶片的LHC II脱离不是一个典型的状态转换现象.