Paeonia suffruticosa Andr.is an endemic shrub flower in China with 2n=10.This study used 228 cultivars from four populations,i.e.,Jiangnan,Japan,Northwest,and Zhongyuan,as materials to explore the genetic diversity le...Paeonia suffruticosa Andr.is an endemic shrub flower in China with 2n=10.This study used 228 cultivars from four populations,i.e.,Jiangnan,Japan,Northwest,and Zhongyuan,as materials to explore the genetic diversity levels among different populations of tree peony varieties.The results showed that 34 bands were amplified using five pairs of cp SSR primers,with an average of 6.8 bands per primer pair.The average number of different alleles(N_(a)),effective alleles(N_(e)),Shannon's information index(I),diversity(H),and polymorphic information content(PIC)were 3.600,2.053,0.708,0.433,and 0.388,respectively.The PIC value was between 0.250 and 0.500,indicating a moderate level of polymorphism for the five cp SSR primer pairs.The genetic diversity levels of peony cultivars varied among different populations,with the Northwest population showing relatively lower levels(I=0.590,H=0.289,and PIC=0.263).A total of 52 haplotypes were identified in the four examined populations,and the number of haplotypes per population ranged from 11 to 22.Forty-four private haplotypes were detected across populations,and the Northwest population exhibiting the highest count of private haplotypes with 17.The mean number of effective number of haplotypes(N_(eh)),haplotypic richness(R_(h)),and diversity(H)were 8.351,6.824,and 0.893,respectively.Analysis of molecular variance indicated that genetic variation within tree peony germplasm was greater than that between germplasm resources,and the main variation was found within individuals of peony germplasm.Cluster analysis,principal coordinate analysis,and genetic structure analysis classified tree peonies from different origins into two groups,indicating a certain degree of genetic differentiation among these four tree peony cultivation groups.This study provides a theoretical basis for the exploration,utilization,and conservation of peony germplasm resources,as well as for research on the breeding of excellent varieties.展开更多
Yellowing of broccoli is a crucial limiting factor for its commercial value and consumer acceptance during postharvest.In this study,the impacts of exogenous melatonin(MEL)on chlorophyll content and fluorescence,as we...Yellowing of broccoli is a crucial limiting factor for its commercial value and consumer acceptance during postharvest.In this study,the impacts of exogenous melatonin(MEL)on chlorophyll content and fluorescence,as well as ultrastructure and membrane lipid metabolism of chloroplasts in broccoli were investigated during postharvest.The results showed that MEL treatment(200 μmol L^(-1))maintained the chlorophyll content,chloroplast autofluorescence and integral structure,and reduced the level ofserotonin in the chloroplasts in broccoli.Also,MEL treatment inhibited the membrane lipid peroxidation of chloroplasts,as indicated by low levels of superoxide anion(O_(2)^(-)),hydrogen peroxide(H_(2)O_(2))and malondialdehyde(MDA),and high levels of endogenous MEL.In addition,the stability and fluidity of chloroplast membranes were also better maintained in the treated broccoli via increasing the contents of phosphatidylglyceroland(PG),monogalactosyldiglyceride(MGDG),digalactosyldiglyceride(DGDG)and unsaturated fatty acids as well as decreasing saturated fatty acid content and the activities of lipoxygenase(LOX)and lipase(LPS).Thus,the application of MEL facilitated the maintenance of chloroplast integrity,thus contributing to yellowing postponement and the extension of the storage life of broccoli.展开更多
Objective:With Persicaria capitata as test materials,we compared and analyzed the chloroplast(cp)genome characteristics as well as their phylogenetic relationships and evolutionary history with related species of Pers...Objective:With Persicaria capitata as test materials,we compared and analyzed the chloroplast(cp)genome characteristics as well as their phylogenetic relationships and evolutionary history with related species of Persicaria nepalensis,Persicaria japonica,Persicaria chinensis,Persicaria filiformis,Persicaria perfoliata,Persicaria pubescens,Persicaria hnydropiper.Methods:The Illumina HiSeq high-throughput sequencing platform was used for the first time for P.capitata cp genome sequencing.NOVOPlasty and CpGAVAS2 were used for assembly and annotation,and Codon W,DnaSP,and MISA were used to conduct a series of comparative genomic analyses between the plant and seven species of the same genus.A phylogenetic tree was constructed using the maximum likelihood(ML)and neighbor-joining(NJ)methods,and divergence time was estimated using BEAST.Results:The total length of P.capitata cp genome was 158,821 bp,with a guanine and cytosine(GC)content of 38.0%,exhibiting a typical circular tetrad structure.The genome contains 127 annotated genes,including 82 protein-coding and 45 tRNA-encoding genes.The cp genome harbors simple sequence repeat(SSR)loci primarily composed of A/T.The conserved species structure of this genus is reinforced by the expansion and contraction of the inverted repeat(IR)region.The non-coding regions of the cp genomes exhibited significant differences among the genera.Six different mutation hotspots(psbK-psbI,atpI-rps2,petN-psbD,atpB-rbcL,cemA-petA,ndhI-ndhA-ycf1)were screened from the non-coding regions of genes with high nucleotide variability(pI).These hotspots were expected to define the phylogenetic species of Persicaria.Furthermore,phylogenetic analysis of Polygonaceae plants showed that P.capitata was more closely related to P.chinensis than P.nepalensis.Analysis of divergence time indicated that Polygonaceae originated in the Late Cretaceous(~180 Ma)and began to differentiate during the Middle Miocene.Persicaria differentiated~66.44 million years ago,during the Miocene.Conclusions:Our findings will serve as a scientific basis for further research on species identification and evolution,population genetics,and phylogenetic analysis of P.capitata.Further,we provide valuable information for understanding the origin and evolution of Persicaria in Polygonaceae and estimating the differentiation time of Persicaria and its population.展开更多
Pentatricopeptide repeat(PPR)proteins perform essential functions in post-transcriptional regulation of gene expression,particularly RNA editing and RNA splicing,in plant organelles.Although research on chloroplast bi...Pentatricopeptide repeat(PPR)proteins perform essential functions in post-transcriptional regulation of gene expression,particularly RNA editing and RNA splicing,in plant organelles.Although research on chloroplast biogenesis and development has been extensive,the functions of most PPR genes in this process in rice(Oryza sativa)remain incompletely understood.This study identifies a novel P-type PPR protein,YELLOW-GREEN LEAF AND SEEDLING LETHALITY(YGS),which localizes to rice chloroplasts.YGS shows predominant expression in leaves.The ygs mutants,generated through CRISPR/Cas9-mediated genome editing of the YGS gene,displayed yellow-green leaves and seedling lethality.These phenotypes corresponded with reduced pigment levels and disrupted chloroplast ultrastructure compared to wild-type plants.Furthermore,the expression of genes associated with chloroplast development and chlorophyll biosynthesis showed significant alterations in the ygs mutants.The absence of YGS function affected RNA editing of rpl2 and intron splicing of ycf3-1 in the plastid genome.Additionally,YGS demonstrated interaction with the chloroplast signal recognition particle protein Oscp SRP54b in yeast two-hybrid and bimolecular fluorescence complementation analyses.These results indicate that YGS participates in RNA editing and RNA splicing in chloroplasts,thus serving a vital role in rice chloroplast development.展开更多
Pyrola atropurpurea Franch is an important annual herbaceous plant.Few genomic analyses have been conducted on this plant,and chloroplast genome research will enrich its genomics basis.This study is based on high-thro...Pyrola atropurpurea Franch is an important annual herbaceous plant.Few genomic analyses have been conducted on this plant,and chloroplast genome research will enrich its genomics basis.This study is based on high-throughput sequencing technology and Bioinformatics methods to obtain the sequence,structure,and other characteristics of the P.atropurpurea chloroplast genome.The result showed that the chloroplast genome of P.atropurpurea has a double-stranded circular structure with a total length of 172,535 bp and a typical four-segment structure.The genome has annotated a total of 132 functional genes,including 43 tRNAs,8 rRNAs,76 protein-coding genes,and 5 pseudo-genes.In total,358 SSR loci were checked out,mainly composed of mononucleotide and trinucleotide repeat.There are three types of scattered repetitive sequences,totaling 4223,including 2452 forward repeats,1763 palindrome repeats,and eight reverse repeats.The optimal codon usage frequency is relatively high with AT usage preference in this genome.Chloroplast genome comparative analysis in the family Ericaceae shows that the overall sequence is more complex,and there are more variations in the gene interval region.The collinearity analysis indicated that there is a complex rearrangement of species between different genera in Ericaceae.The selection pressure analysis showed that the protein-encoding genes rpl33 and rps16 were positively selected among the seven medicinal plants in Ericaceae.The maximum likelihood tree shows that the genetic relationship among P.atropurpurea,Pyrola rotundifolia,and Chimaphila japonica is relatively close.Therefore,an important data basis was provided for species identification,genetic diversity,and phylogenetic studies of P.atropurpurea and even this genus of plants.展开更多
The essential photoprotective role of proton gradient regulation 5(PGR5)-dependent cyclic electron flow(CEF)has been reported in Arabidopsis,rice,and algae.However,its functional assessment has not been performed in t...The essential photoprotective role of proton gradient regulation 5(PGR5)-dependent cyclic electron flow(CEF)has been reported in Arabidopsis,rice,and algae.However,its functional assessment has not been performed in tomato yet.In this study,we focused on elucidate the function of SlPGR5 and SlPGR5-like photosynthetic phenotype 1(PGRL1)in tomato.We performed RNA interference and found that SlPGR5/SlPGRL1-suppressed transformants exhibited extremely low CO_(2)assimilation capacity,their photosystem I(PSI)and PSII were severely photoinhibited and chloroplasts were obviously damaged.The SlPGR5/SlPGRL1-suppressed plants almost completely inhibited CEF and Y(ND),and PSII photoinhibition may be directly related to the inability to produce sufficient proton motive force to induce NPQ.The transgenic plants overexpressing SlPGR5 and SlPGRL1 driven by 35S promoter capable alleviate photoinhibition of plants under low night temperature.The transcriptomic and proteomic analyses suggested that the nuclear gene transcription and turnover of chloroplast proteins,including the plastoglobule-related proteins,were closely related to SlPGR5/SlPGRL1 pathway dependent CEF.The bridge relationship between CEF and chloroplast quality maintenance was a novel report to our knowledge.In conclusion,these results revealed the regulatory mechanism of the SlPGR5/SlPGRL1 pathway in photoprotection and maintenance of chloroplast function in tomato,which is crucial for reduce yield loss,especially under adverse environmental conditions.展开更多
Purines are building blocks for DNA and RNA,found as the energy currency of cells(ATP and GTP),used as signaling molecules(cGMP,cAMP and ATP),and served as precursors for synthesizing primary products such as polysacc...Purines are building blocks for DNA and RNA,found as the energy currency of cells(ATP and GTP),used as signaling molecules(cGMP,cAMP and ATP),and served as precursors for synthesizing primary products such as polysaccharides,sucrose,and phospholipids as well as secondary products(Stasolla et al.,2003;Pareek et al.,2020).Thus,the synthesis of purines is a critical pathway in the cells of all living organisms.Purines can be synthesized through two pathways:de novo and salvage(Stasolla et al.,2003).Recent investigations revealed that purine synthesis is vital for the proper development of chloroplasts in plants.In Arabidopsis,CIA1 encodes the enzyme glutamine phosphoribosyl pyrophosphate amidotransferase,which catalyzes the first committed step of purine de novo biosynthesis,the loss-of-function mutant cia1 shows small,pale-green mosaic leaves(Hung et al.,2004).In rice,both VAL1 and GARS encode glycinamide ribonucleotide synthetase that mediates the second step in purine biosynthesis.展开更多
Leaf color mutants (LCMs) provide crucial insights into the regulatory mechanisms underlying chloroplast development,photo synthesis,and stre ss adaptation.In this study,we identified a temperature-sensitive albino mu...Leaf color mutants (LCMs) provide crucial insights into the regulatory mechanisms underlying chloroplast development,photo synthesis,and stre ss adaptation.In this study,we identified a temperature-sensitive albino mutant,tsa4,characterized by an albino phenotype at the seedling stage and abnormal chloroplast development at temperatures below 25℃.展开更多
Global warming poses a severe threat to rice production and food security.We identified a heat-sensitive mutant hs1 through largescale screening of an established rice mutant library,and subsequently cloned the corres...Global warming poses a severe threat to rice production and food security.We identified a heat-sensitive mutant hs1 through largescale screening of an established rice mutant library,and subsequently cloned the corresponding gene HS1,which confers thermotolerance in rice.HS1 is localized to the chloroplast and functions by preserving chloroplast integrity under elevated temperatures through stabilizing the photosystem I subunit protein PsaC.Loss of HS1 function in the hs1 mutant leads to severe structural damage to the chloroplast under heat stress,accompanied by intracellular accumulation of reactive oxygen species(ROS),which in turn triggers DNA damage and leaf albinism,ultimately manifesting as a heat-sensitive phenotype.展开更多
Chloroplasts are essential for normal plant growth and development.In plants,pentatricopeptide repeat(PPR)proteins mediate RNA processing in chloroplasts.Here,we characterized a rice albino leaf 5(al5)mutant which exh...Chloroplasts are essential for normal plant growth and development.In plants,pentatricopeptide repeat(PPR)proteins mediate RNA processing in chloroplasts.Here,we characterized a rice albino leaf 5(al5)mutant which exhibits albinism during early leaf development.The MutMap+analysis and transformation experiments revealed that AL5 encodes a chloroplast-localized P-type PPR protein.The AL5 mutation resulted in the defective splicing of ribosomal protein L2(rpl2)and ribosomal protein S12(rps12),which are involved in the synthesis of chloroplast 50S and 30S ribosomal subunits,respectively.The RNA-electrophoretic mobility shift assay(REMSA)further demonstrated that AL5 directly binds to rpl2 transcripts.Finally,disruption of AL5 led to reduced expression of plastid-encoded polymerase(PEP)-dependent plastid genes and nuclear-encoded photosynthetic genes.Notably,the albino al5 mutant phenotype was regulated by low temperature.These results suggest that AL5 participates in plastid RNA splicing and plays an important role in chloroplast development in rice.展开更多
Along with the development of modern molecular biology technologies, complete chloroplast genomes have been sequenced in various plant species to date, and the structure, function and expression of these genes have be...Along with the development of modern molecular biology technologies, complete chloroplast genomes have been sequenced in various plant species to date, and the structure, function and expression of these genes have been deter-mined. The chloroplast genome structure in most higher plants is stable, since the gene number, arrangement and composition are conservative. The determination of sugarcane chloroplast genome sequence laid a good foundation for sugarcane chloroplast related research. This article gives a review on the research progress of sugarcane chloroplast genome through the chloroplast genome map, gene structure, function, chloroplast RNA editing, and phylogenetic analysis in Saccharum and relat-ed genera. This study held great potential to clarify more directions in researches, including sugarcane chloroplast genetic transformation, complete chloroplast nu-cleotide sequence determination in Saccharum and closely related genera, cpSSRs development and application.展开更多
The inheritance of mitochondrial (mt) DNA and chloroplast (cp) DNA was investigated in intergeneric hybrids from crossing between Cunninghamia lanceolata (Lamb.) Hook. and Cryptomeria fortunei Hooibrenk. The c...The inheritance of mitochondrial (mt) DNA and chloroplast (cp) DNA was investigated in intergeneric hybrids from crossing between Cunninghamia lanceolata (Lamb.) Hook. and Cryptomeria fortunei Hooibrenk. The chloroplast trnL trnF region and one intra genic segment of the mitochondrial gene, Cox Ⅲ, were amplified from those of the parents and hybrids by PCR using gene specific primers. Cp and mtDNA polymorphisms of the amplified regions were detected between the parents after restriction digestions. Restriction fragment length polymorphism (RFLP) analysis revealed that all the F 1 individuals possessed Cox Ⅲ restriction fragment patterns (characteristic of the paternal parent Cryptomeria fortunei ) and the trnL trnF region (identical to the maternal parent Cunninghamia lanceolata ) showing that a different mode of inheritance for organelle DNA has occurred in the hybrids. Furthermore, the maternal inheritance of chloroplast DNA is reported here for the first time in coniferophyta.展开更多
Chloroplast simple sequence repeat (cpSSR) markers in Citrus were developed and successfully used to analyze chloroplast genome inheritance of Citrus somatic hybrids. Twenty-two previously reported cpSSR primer pairs ...Chloroplast simple sequence repeat (cpSSR) markers in Citrus were developed and successfully used to analyze chloroplast genome inheritance of Citrus somatic hybrids. Twenty-two previously reported cpSSR primer pairs from pine (Pinus thunbergii Parl.), rice (Otyza sativa L.) and tobacco (Nicotiana tabacum L.) were tested in Citrus, nine of which could amplify intensive PCR products by agarose gel electrophoresis. Chloroplast genome inheritance of Citrus somatic hybrids from nine fusions was then analyzed, and five of the nine pre-screened primer pairs showed polymorphisms by polyacrylamide gel electrophoresis. The results revealed the random inheritance nature of chloroplast genome in all analyzed Citrus somatic hybrids, which was in agreement with previous reports based on RFLP or CAPS analyses. It was also shown that cpSSR is a more efficient tool in chloroplast genome analyses of somatic hybrids in higher plants, compared with the conventional RFLP or CAPS analyses.展开更多
PPF1 is a vegetative growth related gene that encodes a putative membrane protein having high homology with Arabidopsis chloroplast thylakoid protein ALB3. Immunoelectron microscopic assay showed that PPF1 was mainly ...PPF1 is a vegetative growth related gene that encodes a putative membrane protein having high homology with Arabidopsis chloroplast thylakoid protein ALB3. Immunoelectron microscopic assay showed that PPF1 was mainly localized in the thylakold membrane and was highly expressed in well-developed chloroplasts of short day (SD) grown G2 pea while having a very low abundance in chloroplasts of long day (LD) grown plants two weeks after flowering. Comparison of the leaf senescence processes in transgenic Arabidopsis and wild type plants revealed that overexpression of PPF1 delayed leaf senescence, while the depression of its Arabidopsts homologue (ALB3) with PPF1 antisense mRNA accelerated leaf senescence obviously. Ultrastructural analysis of transgenic Arabidopsis plants showed that when PPF1 was overexpressed in Arabidopsis, the chloroplasts were bigger and had much more grana and stroma thylakoid membranes than those of wild type plants. On the contrary, when PPF1 was expressed in antisense orientation to reduce the level of PPF1 homologue in Arabidopsis, the transgenic plants had smaller chloroplasts With less grana. and poorly developed thylakoid membrane systems. These results suggested that the developmental status of chloroplasts was positively correlated with the level of PPF1 or its Arabidopsts homologue, ALB3. Our results suggested that PPF1 gene might regulate plant development by controlling chloroplast development.展开更多
The changes of chlorophyll_protein complexes and photosynthetic activities of chloroplast isolated from lotus ( Nelumbo nucifera Gaertn.) seeds germinating under illumination were studied. SDS PAGE analysis of c...The changes of chlorophyll_protein complexes and photosynthetic activities of chloroplast isolated from lotus ( Nelumbo nucifera Gaertn.) seeds germinating under illumination were studied. SDS PAGE analysis of chlorophyll_protein complexes showed that there was only the light harvesting chlorophyll a/b protein complex from PSⅡ (LHCⅡ) precursor in chloroplast from lotus seeds germinated for 2 to 6 days, while LHC Ⅱ 1, and the chlorophyll_protein complex of PSⅠ (CPⅠ) appeared on the 8th day of germination and PSⅡ reaction center complex appeared later. Studies on the polypeptides composition of the chloroplast revealed the following results: 1) Small amount of the 27 kD polypeptide was synthesized in invisible light; 2) The 30 kD polypeptide existed previously in the plumules of the dry seeds; 3) The amount of the 30 kD polypeptide was more than any other polypeptides before germination and decreased gradually throughout germination, while the 27 kD polypeptide changed in the opposite way; 4) In the process of germination, measurement of the electron transport rate and the fluorescence induction kinetics at room temperature showed that PSⅡ activities and efficiency of primary light energy transformation were only experimentally measurable after 7 days of germination and gradually increased afterwards. At the same time, the chl a/b ratio rose from the lower value to normal; 5) The changes of chloroplast membrane components and its functions are concomitant in concert with that of the ultrastructure of chloroplast membranes during germination, as shown in our earlier work . The results have proved again that a different developmental pathway of chloroplast is likely to exist in the lotus plumules, which might provide an important clue for N. nucifera in having an unique position in the phylogeny of the angiosperm.展开更多
[Objective]The aim was to research the relationship and genetic diversity of Indocalamus.[Method]Using 13 samples of Indocalamus and 3 samples of Sasa as materials,the intergenic regions of trnL-trnF gene in chloropla...[Objective]The aim was to research the relationship and genetic diversity of Indocalamus.[Method]Using 13 samples of Indocalamus and 3 samples of Sasa as materials,the intergenic regions of trnL-trnF gene in chloroplast were amplified by PCR,and sequence analysis and phylogenetic trees construction were carried out.[Result]Using the universal primer,the intergenic regions of trnL-trnF were amplified,the lengths of the segments varied from 1 008 bp to 1 103 bp,of which 940 bp was compared.The dendrogram of trnL-trnF sequences showed that Indocalamus and Sasa were clustered together and they were homologous by 99%.All the samples were divided into five groups,the first group included 12 samples such as Indosalamus pedalis,I.pumilus,I.victorialis,I.longiauritus,I.tessellatus,Sasa sinica,Sasa pygmaea,I.barbatus,I.guangdongensis,I.herklotsii,I.Hirtivaginatus and S.fortunei.I.decorus,I.lacunosus,I.Latifolius and I.Migoi were respectively divided into four groups.[Conclusion]The high homology of all samples showed the low evolution speed and little information sites which suggested that the phylogeny of Indocalamus could not be well resolved by the intergenic region of trnL-trnF.展开更多
[Objective] This study aimed to construct Brassica napus chloroplast multi- cistron double cross-over expression vector, to lay the foundation for the genetic engi- neering research of Brassica napus chloroplast. [Met...[Objective] This study aimed to construct Brassica napus chloroplast multi- cistron double cross-over expression vector, to lay the foundation for the genetic engi- neering research of Brassica napus chloroplast. [Method] Two primers were designed based on the known Brassica napus chloroplast DNA sequences AF267640 and Z50868 in GenBank. By using PCR method, two Brassica napus L. chloroplast DNA fragments were obtained, which were named RbcL and ACCD. The two Brassica na- pus chloroplast DNA homologous fragments were then cloned into plasmid pMD18-T to obtain recombinant plasmid pHBM715. Tandem expression cassette harboring spectinomycin-resistant gene aadA, mannanase gene man and green fluorescent pro- tein gene gfp was cloned into the plasmid pHBM715, thereby constructing Brassica napus chloroplast multicistron double cross-over expression vector pHBM716, which was transformed into Escherichia coil for expression and identification. [Result] Plate qualitative analysis was conducted for the functional identification of expression cas- sette in the constructed Brassica napus chloroplast multicistron double cross-over ex- pression vector, results showed that the three genes of the same multicistron were all expressed in E. coil [Conclusion] This study successfully constructed Brassica napus chloroplast multicistron double cross-over expression vector, which laid the foundation for the genetic engineering of Brassica napus chloroplast.展开更多
Wheat ( Triticum aestivum L.) plants were grown under ambient and doubled_CO 2(plus 350 μL/L) concentration in cylindrical open_top chamber to examine their effects on the ultrastructure, supramolecular architect...Wheat ( Triticum aestivum L.) plants were grown under ambient and doubled_CO 2(plus 350 μL/L) concentration in cylindrical open_top chamber to examine their effects on the ultrastructure, supramolecular architecture, absorption spectrum and low temperature (77 K) fluorescence emission spectrum of the chloroplasts from wheat leaves. The results were briefly summarized as follows: (1) The wheat leaves possessed normally developed chloroplasts with intact grana and stroma thylakoid membranes; The grana intertwined with stroma thylakoid membranes and increased slightly in stacking degree and the width of granum, in spite of more accumulated starch grains within the chloroplasts than those in control; (2) The particle density in the stacked region of the endoplasmic fracture face (EFs) and protoplasmic fracture face (PFs) and in the unstacked region the endoplasmic fracture face (EFu) and the protoplasmic fracture face (PFu) was significantly higher than that of control. Furthermore, in some cases many more particles on EFs faces of thylakoid membranes appeared as a paracrystalline particle array; (3) The variations in the structure of chloroplasts were consistent with the absorption spectra and the low temperature (77 K) fluorescence emission spectra of the chloroplasts developed under the doubled_CO 2 concentration. Results indicate that the capability of light energy absorption of chloroplasts and regulative capability of excitation energy distribution between PSⅡ and PSⅠ were raised by doubled_CO 2 concentration. This is very favorable for final productivity of wheat.展开更多
基金supported by Innovation Scientists and Technicians Troop Construction Projects of Henan Province(Grant No.212101510003)the Central Plains Scholar Workstation Project(Grant No.224400510002)+1 种基金the Youth Science Foundation of Henan Province(Grant No.202300410136)the Experimental Development Foundation of Henan University of Science and Technology(Grant No.SY2324004)。
文摘Paeonia suffruticosa Andr.is an endemic shrub flower in China with 2n=10.This study used 228 cultivars from four populations,i.e.,Jiangnan,Japan,Northwest,and Zhongyuan,as materials to explore the genetic diversity levels among different populations of tree peony varieties.The results showed that 34 bands were amplified using five pairs of cp SSR primers,with an average of 6.8 bands per primer pair.The average number of different alleles(N_(a)),effective alleles(N_(e)),Shannon's information index(I),diversity(H),and polymorphic information content(PIC)were 3.600,2.053,0.708,0.433,and 0.388,respectively.The PIC value was between 0.250 and 0.500,indicating a moderate level of polymorphism for the five cp SSR primer pairs.The genetic diversity levels of peony cultivars varied among different populations,with the Northwest population showing relatively lower levels(I=0.590,H=0.289,and PIC=0.263).A total of 52 haplotypes were identified in the four examined populations,and the number of haplotypes per population ranged from 11 to 22.Forty-four private haplotypes were detected across populations,and the Northwest population exhibiting the highest count of private haplotypes with 17.The mean number of effective number of haplotypes(N_(eh)),haplotypic richness(R_(h)),and diversity(H)were 8.351,6.824,and 0.893,respectively.Analysis of molecular variance indicated that genetic variation within tree peony germplasm was greater than that between germplasm resources,and the main variation was found within individuals of peony germplasm.Cluster analysis,principal coordinate analysis,and genetic structure analysis classified tree peonies from different origins into two groups,indicating a certain degree of genetic differentiation among these four tree peony cultivation groups.This study provides a theoretical basis for the exploration,utilization,and conservation of peony germplasm resources,as well as for research on the breeding of excellent varieties.
基金supported by the National Natural Science Foundation of China(Grant No.32372408)the National Natural Science Foundation of China for Youth(Grant No.32102041).
文摘Yellowing of broccoli is a crucial limiting factor for its commercial value and consumer acceptance during postharvest.In this study,the impacts of exogenous melatonin(MEL)on chlorophyll content and fluorescence,as well as ultrastructure and membrane lipid metabolism of chloroplasts in broccoli were investigated during postharvest.The results showed that MEL treatment(200 μmol L^(-1))maintained the chlorophyll content,chloroplast autofluorescence and integral structure,and reduced the level ofserotonin in the chloroplasts in broccoli.Also,MEL treatment inhibited the membrane lipid peroxidation of chloroplasts,as indicated by low levels of superoxide anion(O_(2)^(-)),hydrogen peroxide(H_(2)O_(2))and malondialdehyde(MDA),and high levels of endogenous MEL.In addition,the stability and fluidity of chloroplast membranes were also better maintained in the treated broccoli via increasing the contents of phosphatidylglyceroland(PG),monogalactosyldiglyceride(MGDG),digalactosyldiglyceride(DGDG)and unsaturated fatty acids as well as decreasing saturated fatty acid content and the activities of lipoxygenase(LOX)and lipase(LPS).Thus,the application of MEL facilitated the maintenance of chloroplast integrity,thus contributing to yellowing postponement and the extension of the storage life of broccoli.
基金supported by the National Natural Science Foundation of China(82060913).
文摘Objective:With Persicaria capitata as test materials,we compared and analyzed the chloroplast(cp)genome characteristics as well as their phylogenetic relationships and evolutionary history with related species of Persicaria nepalensis,Persicaria japonica,Persicaria chinensis,Persicaria filiformis,Persicaria perfoliata,Persicaria pubescens,Persicaria hnydropiper.Methods:The Illumina HiSeq high-throughput sequencing platform was used for the first time for P.capitata cp genome sequencing.NOVOPlasty and CpGAVAS2 were used for assembly and annotation,and Codon W,DnaSP,and MISA were used to conduct a series of comparative genomic analyses between the plant and seven species of the same genus.A phylogenetic tree was constructed using the maximum likelihood(ML)and neighbor-joining(NJ)methods,and divergence time was estimated using BEAST.Results:The total length of P.capitata cp genome was 158,821 bp,with a guanine and cytosine(GC)content of 38.0%,exhibiting a typical circular tetrad structure.The genome contains 127 annotated genes,including 82 protein-coding and 45 tRNA-encoding genes.The cp genome harbors simple sequence repeat(SSR)loci primarily composed of A/T.The conserved species structure of this genus is reinforced by the expansion and contraction of the inverted repeat(IR)region.The non-coding regions of the cp genomes exhibited significant differences among the genera.Six different mutation hotspots(psbK-psbI,atpI-rps2,petN-psbD,atpB-rbcL,cemA-petA,ndhI-ndhA-ycf1)were screened from the non-coding regions of genes with high nucleotide variability(pI).These hotspots were expected to define the phylogenetic species of Persicaria.Furthermore,phylogenetic analysis of Polygonaceae plants showed that P.capitata was more closely related to P.chinensis than P.nepalensis.Analysis of divergence time indicated that Polygonaceae originated in the Late Cretaceous(~180 Ma)and began to differentiate during the Middle Miocene.Persicaria differentiated~66.44 million years ago,during the Miocene.Conclusions:Our findings will serve as a scientific basis for further research on species identification and evolution,population genetics,and phylogenetic analysis of P.capitata.Further,we provide valuable information for understanding the origin and evolution of Persicaria in Polygonaceae and estimating the differentiation time of Persicaria and its population.
基金supported by the National Natural Science Foundation of China(32201784,32072048,and U2004204)the Natural Science Foundation of Shandong Province,China(ZR2020QC111 and ZR2022QC176)the Talent Introduction Project of Dezhou University,China(2020xjrc207)。
文摘Pentatricopeptide repeat(PPR)proteins perform essential functions in post-transcriptional regulation of gene expression,particularly RNA editing and RNA splicing,in plant organelles.Although research on chloroplast biogenesis and development has been extensive,the functions of most PPR genes in this process in rice(Oryza sativa)remain incompletely understood.This study identifies a novel P-type PPR protein,YELLOW-GREEN LEAF AND SEEDLING LETHALITY(YGS),which localizes to rice chloroplasts.YGS shows predominant expression in leaves.The ygs mutants,generated through CRISPR/Cas9-mediated genome editing of the YGS gene,displayed yellow-green leaves and seedling lethality.These phenotypes corresponded with reduced pigment levels and disrupted chloroplast ultrastructure compared to wild-type plants.Furthermore,the expression of genes associated with chloroplast development and chlorophyll biosynthesis showed significant alterations in the ygs mutants.The absence of YGS function affected RNA editing of rpl2 and intron splicing of ycf3-1 in the plastid genome.Additionally,YGS demonstrated interaction with the chloroplast signal recognition particle protein Oscp SRP54b in yeast two-hybrid and bimolecular fluorescence complementation analyses.These results indicate that YGS participates in RNA editing and RNA splicing in chloroplasts,thus serving a vital role in rice chloroplast development.
基金supported by the Education Reform Program of Jiangxi Provincial Department of Education(JXJG-22-23-3,JXJG-23-23-5)the“Biology and Medicine”Discipline Construction Project of Nanchang NormalUniversity(100/20149)+2 种基金Jiangxi Province Key Laboratory of Oil Crops Biology(YLKFKT202203)the Education Reform Program of Nanchang Normal University(NSJG-21-25)Nanchang Key Laboratory of Comprehensive Research and Development of Brasenia schreberi(32060078).
文摘Pyrola atropurpurea Franch is an important annual herbaceous plant.Few genomic analyses have been conducted on this plant,and chloroplast genome research will enrich its genomics basis.This study is based on high-throughput sequencing technology and Bioinformatics methods to obtain the sequence,structure,and other characteristics of the P.atropurpurea chloroplast genome.The result showed that the chloroplast genome of P.atropurpurea has a double-stranded circular structure with a total length of 172,535 bp and a typical four-segment structure.The genome has annotated a total of 132 functional genes,including 43 tRNAs,8 rRNAs,76 protein-coding genes,and 5 pseudo-genes.In total,358 SSR loci were checked out,mainly composed of mononucleotide and trinucleotide repeat.There are three types of scattered repetitive sequences,totaling 4223,including 2452 forward repeats,1763 palindrome repeats,and eight reverse repeats.The optimal codon usage frequency is relatively high with AT usage preference in this genome.Chloroplast genome comparative analysis in the family Ericaceae shows that the overall sequence is more complex,and there are more variations in the gene interval region.The collinearity analysis indicated that there is a complex rearrangement of species between different genera in Ericaceae.The selection pressure analysis showed that the protein-encoding genes rpl33 and rps16 were positively selected among the seven medicinal plants in Ericaceae.The maximum likelihood tree shows that the genetic relationship among P.atropurpurea,Pyrola rotundifolia,and Chimaphila japonica is relatively close.Therefore,an important data basis was provided for species identification,genetic diversity,and phylogenetic studies of P.atropurpurea and even this genus of plants.
基金supported by the National Natural Science Foundation of China(Grant Nos.32072651,31772356)China Agriculture Research System of MOF and MARA(Grant No.CARS23)+1 种基金Joint Fund for Innovation Enhancement of Liaoning Province(Grant No.2021-NLTS-11-01)Support Program for Young and middle-aged Scientific and technological Innovation Talents(Grant No.RC210293)。
文摘The essential photoprotective role of proton gradient regulation 5(PGR5)-dependent cyclic electron flow(CEF)has been reported in Arabidopsis,rice,and algae.However,its functional assessment has not been performed in tomato yet.In this study,we focused on elucidate the function of SlPGR5 and SlPGR5-like photosynthetic phenotype 1(PGRL1)in tomato.We performed RNA interference and found that SlPGR5/SlPGRL1-suppressed transformants exhibited extremely low CO_(2)assimilation capacity,their photosystem I(PSI)and PSII were severely photoinhibited and chloroplasts were obviously damaged.The SlPGR5/SlPGRL1-suppressed plants almost completely inhibited CEF and Y(ND),and PSII photoinhibition may be directly related to the inability to produce sufficient proton motive force to induce NPQ.The transgenic plants overexpressing SlPGR5 and SlPGRL1 driven by 35S promoter capable alleviate photoinhibition of plants under low night temperature.The transcriptomic and proteomic analyses suggested that the nuclear gene transcription and turnover of chloroplast proteins,including the plastoglobule-related proteins,were closely related to SlPGR5/SlPGRL1 pathway dependent CEF.The bridge relationship between CEF and chloroplast quality maintenance was a novel report to our knowledge.In conclusion,these results revealed the regulatory mechanism of the SlPGR5/SlPGRL1 pathway in photoprotection and maintenance of chloroplast function in tomato,which is crucial for reduce yield loss,especially under adverse environmental conditions.
基金funded by the National Natural Science Foundation of China(Grant No.32202485)the Fund for Distinguished Young Scholars from Henan Academy of Agricultural Sciences(Grant No.2024JQ02)+1 种基金the Zhongyuan Sci-Tech Innovation Leading Talents(Grant No.244200510041)the Key SciTech R&D Project of Joint Foundation in Henan Province(Grant No.232301420024).
文摘Purines are building blocks for DNA and RNA,found as the energy currency of cells(ATP and GTP),used as signaling molecules(cGMP,cAMP and ATP),and served as precursors for synthesizing primary products such as polysaccharides,sucrose,and phospholipids as well as secondary products(Stasolla et al.,2003;Pareek et al.,2020).Thus,the synthesis of purines is a critical pathway in the cells of all living organisms.Purines can be synthesized through two pathways:de novo and salvage(Stasolla et al.,2003).Recent investigations revealed that purine synthesis is vital for the proper development of chloroplasts in plants.In Arabidopsis,CIA1 encodes the enzyme glutamine phosphoribosyl pyrophosphate amidotransferase,which catalyzes the first committed step of purine de novo biosynthesis,the loss-of-function mutant cia1 shows small,pale-green mosaic leaves(Hung et al.,2004).In rice,both VAL1 and GARS encode glycinamide ribonucleotide synthetase that mediates the second step in purine biosynthesis.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.32341026 and 32171998)the Hunan Provincial Science and Technology Innovation Program,China(Grant No.2023NK1010)the Changsha Natural Science Foundation,China(Grant No.20209001).
文摘Leaf color mutants (LCMs) provide crucial insights into the regulatory mechanisms underlying chloroplast development,photo synthesis,and stre ss adaptation.In this study,we identified a temperature-sensitive albino mutant,tsa4,characterized by an albino phenotype at the seedling stage and abnormal chloroplast development at temperatures below 25℃.
基金supported by the National Natural Science Foundation of China(Grant Nos.32372118 and 32188102)the Zhejiang Natural Science Foundation,China(Grant No.LZ25C130010)+1 种基金the Qian Qian Academician Workstation,and the specific research fund of the Innovation Platform for Academicians of Hainan Province,China(Grant No.YSPTZX202303)the Central Public-Interest Scientific Institution Basal Research Fund from Chinese Academy of Agricultural Sciences(Grant No.Y2025YC93)。
文摘Global warming poses a severe threat to rice production and food security.We identified a heat-sensitive mutant hs1 through largescale screening of an established rice mutant library,and subsequently cloned the corresponding gene HS1,which confers thermotolerance in rice.HS1 is localized to the chloroplast and functions by preserving chloroplast integrity under elevated temperatures through stabilizing the photosystem I subunit protein PsaC.Loss of HS1 function in the hs1 mutant leads to severe structural damage to the chloroplast under heat stress,accompanied by intracellular accumulation of reactive oxygen species(ROS),which in turn triggers DNA damage and leaf albinism,ultimately manifesting as a heat-sensitive phenotype.
基金supported by the Open Competition Program of Top Ten Critical Priorities of Agricultural Science and Technology Innovation for the 14th Five-Year Plan of Guangdong Province(2022SDZG05)the Guangdong Province Rural Revitalization Strategy Special Fund Seed Industry Revitalization Project(2022-NJS-15-001)the Key-Area Research and Development Program of Guangdong Province(2022B0202060005).
文摘Chloroplasts are essential for normal plant growth and development.In plants,pentatricopeptide repeat(PPR)proteins mediate RNA processing in chloroplasts.Here,we characterized a rice albino leaf 5(al5)mutant which exhibits albinism during early leaf development.The MutMap+analysis and transformation experiments revealed that AL5 encodes a chloroplast-localized P-type PPR protein.The AL5 mutation resulted in the defective splicing of ribosomal protein L2(rpl2)and ribosomal protein S12(rps12),which are involved in the synthesis of chloroplast 50S and 30S ribosomal subunits,respectively.The RNA-electrophoretic mobility shift assay(REMSA)further demonstrated that AL5 directly binds to rpl2 transcripts.Finally,disruption of AL5 led to reduced expression of plastid-encoded polymerase(PEP)-dependent plastid genes and nuclear-encoded photosynthetic genes.Notably,the albino al5 mutant phenotype was regulated by low temperature.These results suggest that AL5 participates in plastid RNA splicing and plays an important role in chloroplast development in rice.
基金Supported by National Natural Science Foundation of China(31360357)Natural Science Foundation of Guangxi Zhuang Autonomous Region(2013GXNSFAA019051)Earmarked Fund for China Agriculture Research System(CARS-20-1-3)~~
文摘Along with the development of modern molecular biology technologies, complete chloroplast genomes have been sequenced in various plant species to date, and the structure, function and expression of these genes have been deter-mined. The chloroplast genome structure in most higher plants is stable, since the gene number, arrangement and composition are conservative. The determination of sugarcane chloroplast genome sequence laid a good foundation for sugarcane chloroplast related research. This article gives a review on the research progress of sugarcane chloroplast genome through the chloroplast genome map, gene structure, function, chloroplast RNA editing, and phylogenetic analysis in Saccharum and relat-ed genera. This study held great potential to clarify more directions in researches, including sugarcane chloroplast genetic transformation, complete chloroplast nu-cleotide sequence determination in Saccharum and closely related genera, cpSSRs development and application.
文摘The inheritance of mitochondrial (mt) DNA and chloroplast (cp) DNA was investigated in intergeneric hybrids from crossing between Cunninghamia lanceolata (Lamb.) Hook. and Cryptomeria fortunei Hooibrenk. The chloroplast trnL trnF region and one intra genic segment of the mitochondrial gene, Cox Ⅲ, were amplified from those of the parents and hybrids by PCR using gene specific primers. Cp and mtDNA polymorphisms of the amplified regions were detected between the parents after restriction digestions. Restriction fragment length polymorphism (RFLP) analysis revealed that all the F 1 individuals possessed Cox Ⅲ restriction fragment patterns (characteristic of the paternal parent Cryptomeria fortunei ) and the trnL trnF region (identical to the maternal parent Cunninghamia lanceolata ) showing that a different mode of inheritance for organelle DNA has occurred in the hybrids. Furthermore, the maternal inheritance of chloroplast DNA is reported here for the first time in coniferophyta.
文摘Chloroplast simple sequence repeat (cpSSR) markers in Citrus were developed and successfully used to analyze chloroplast genome inheritance of Citrus somatic hybrids. Twenty-two previously reported cpSSR primer pairs from pine (Pinus thunbergii Parl.), rice (Otyza sativa L.) and tobacco (Nicotiana tabacum L.) were tested in Citrus, nine of which could amplify intensive PCR products by agarose gel electrophoresis. Chloroplast genome inheritance of Citrus somatic hybrids from nine fusions was then analyzed, and five of the nine pre-screened primer pairs showed polymorphisms by polyacrylamide gel electrophoresis. The results revealed the random inheritance nature of chloroplast genome in all analyzed Citrus somatic hybrids, which was in agreement with previous reports based on RFLP or CAPS analyses. It was also shown that cpSSR is a more efficient tool in chloroplast genome analyses of somatic hybrids in higher plants, compared with the conventional RFLP or CAPS analyses.
文摘PPF1 is a vegetative growth related gene that encodes a putative membrane protein having high homology with Arabidopsis chloroplast thylakoid protein ALB3. Immunoelectron microscopic assay showed that PPF1 was mainly localized in the thylakold membrane and was highly expressed in well-developed chloroplasts of short day (SD) grown G2 pea while having a very low abundance in chloroplasts of long day (LD) grown plants two weeks after flowering. Comparison of the leaf senescence processes in transgenic Arabidopsis and wild type plants revealed that overexpression of PPF1 delayed leaf senescence, while the depression of its Arabidopsts homologue (ALB3) with PPF1 antisense mRNA accelerated leaf senescence obviously. Ultrastructural analysis of transgenic Arabidopsis plants showed that when PPF1 was overexpressed in Arabidopsis, the chloroplasts were bigger and had much more grana and stroma thylakoid membranes than those of wild type plants. On the contrary, when PPF1 was expressed in antisense orientation to reduce the level of PPF1 homologue in Arabidopsis, the transgenic plants had smaller chloroplasts With less grana. and poorly developed thylakoid membrane systems. These results suggested that the developmental status of chloroplasts was positively correlated with the level of PPF1 or its Arabidopsts homologue, ALB3. Our results suggested that PPF1 gene might regulate plant development by controlling chloroplast development.
文摘The changes of chlorophyll_protein complexes and photosynthetic activities of chloroplast isolated from lotus ( Nelumbo nucifera Gaertn.) seeds germinating under illumination were studied. SDS PAGE analysis of chlorophyll_protein complexes showed that there was only the light harvesting chlorophyll a/b protein complex from PSⅡ (LHCⅡ) precursor in chloroplast from lotus seeds germinated for 2 to 6 days, while LHC Ⅱ 1, and the chlorophyll_protein complex of PSⅠ (CPⅠ) appeared on the 8th day of germination and PSⅡ reaction center complex appeared later. Studies on the polypeptides composition of the chloroplast revealed the following results: 1) Small amount of the 27 kD polypeptide was synthesized in invisible light; 2) The 30 kD polypeptide existed previously in the plumules of the dry seeds; 3) The amount of the 30 kD polypeptide was more than any other polypeptides before germination and decreased gradually throughout germination, while the 27 kD polypeptide changed in the opposite way; 4) In the process of germination, measurement of the electron transport rate and the fluorescence induction kinetics at room temperature showed that PSⅡ activities and efficiency of primary light energy transformation were only experimentally measurable after 7 days of germination and gradually increased afterwards. At the same time, the chl a/b ratio rose from the lower value to normal; 5) The changes of chloroplast membrane components and its functions are concomitant in concert with that of the ultrastructure of chloroplast membranes during germination, as shown in our earlier work . The results have proved again that a different developmental pathway of chloroplast is likely to exist in the lotus plumules, which might provide an important clue for N. nucifera in having an unique position in the phylogeny of the angiosperm.
基金the Supporting Program of the "Eleventh Five-year Plan" for Sci & Tech Research (2006BAD19B0202)The Programof Special Funds for basic scientific research of International Center for Bamboo and Rattan (1632009007)Foundation Item of International Center for Bamboo and Rattan (06 /07-C22)~~
文摘[Objective]The aim was to research the relationship and genetic diversity of Indocalamus.[Method]Using 13 samples of Indocalamus and 3 samples of Sasa as materials,the intergenic regions of trnL-trnF gene in chloroplast were amplified by PCR,and sequence analysis and phylogenetic trees construction were carried out.[Result]Using the universal primer,the intergenic regions of trnL-trnF were amplified,the lengths of the segments varied from 1 008 bp to 1 103 bp,of which 940 bp was compared.The dendrogram of trnL-trnF sequences showed that Indocalamus and Sasa were clustered together and they were homologous by 99%.All the samples were divided into five groups,the first group included 12 samples such as Indosalamus pedalis,I.pumilus,I.victorialis,I.longiauritus,I.tessellatus,Sasa sinica,Sasa pygmaea,I.barbatus,I.guangdongensis,I.herklotsii,I.Hirtivaginatus and S.fortunei.I.decorus,I.lacunosus,I.Latifolius and I.Migoi were respectively divided into four groups.[Conclusion]The high homology of all samples showed the low evolution speed and little information sites which suggested that the phylogeny of Indocalamus could not be well resolved by the intergenic region of trnL-trnF.
基金Supported by National 863 Project of China (2002AA227011)Natural Science Foundation of Hubei Province (2003ABAI18)Natural Science Foundation of Shandong Province (ZR2010HQ054)~~
文摘[Objective] This study aimed to construct Brassica napus chloroplast multi- cistron double cross-over expression vector, to lay the foundation for the genetic engi- neering research of Brassica napus chloroplast. [Method] Two primers were designed based on the known Brassica napus chloroplast DNA sequences AF267640 and Z50868 in GenBank. By using PCR method, two Brassica napus L. chloroplast DNA fragments were obtained, which were named RbcL and ACCD. The two Brassica na- pus chloroplast DNA homologous fragments were then cloned into plasmid pMD18-T to obtain recombinant plasmid pHBM715. Tandem expression cassette harboring spectinomycin-resistant gene aadA, mannanase gene man and green fluorescent pro- tein gene gfp was cloned into the plasmid pHBM715, thereby constructing Brassica napus chloroplast multicistron double cross-over expression vector pHBM716, which was transformed into Escherichia coil for expression and identification. [Result] Plate qualitative analysis was conducted for the functional identification of expression cas- sette in the constructed Brassica napus chloroplast multicistron double cross-over ex- pression vector, results showed that the three genes of the same multicistron were all expressed in E. coil [Conclusion] This study successfully constructed Brassica napus chloroplast multicistron double cross-over expression vector, which laid the foundation for the genetic engineering of Brassica napus chloroplast.
文摘Wheat ( Triticum aestivum L.) plants were grown under ambient and doubled_CO 2(plus 350 μL/L) concentration in cylindrical open_top chamber to examine their effects on the ultrastructure, supramolecular architecture, absorption spectrum and low temperature (77 K) fluorescence emission spectrum of the chloroplasts from wheat leaves. The results were briefly summarized as follows: (1) The wheat leaves possessed normally developed chloroplasts with intact grana and stroma thylakoid membranes; The grana intertwined with stroma thylakoid membranes and increased slightly in stacking degree and the width of granum, in spite of more accumulated starch grains within the chloroplasts than those in control; (2) The particle density in the stacked region of the endoplasmic fracture face (EFs) and protoplasmic fracture face (PFs) and in the unstacked region the endoplasmic fracture face (EFu) and the protoplasmic fracture face (PFu) was significantly higher than that of control. Furthermore, in some cases many more particles on EFs faces of thylakoid membranes appeared as a paracrystalline particle array; (3) The variations in the structure of chloroplasts were consistent with the absorption spectra and the low temperature (77 K) fluorescence emission spectra of the chloroplasts developed under the doubled_CO 2 concentration. Results indicate that the capability of light energy absorption of chloroplasts and regulative capability of excitation energy distribution between PSⅡ and PSⅠ were raised by doubled_CO 2 concentration. This is very favorable for final productivity of wheat.