The NAC Transcription Factor ANAC089 Modulates Seed Vigor through the ABI5-VTC2 Module in Arabidopsis thaliana

Seed viability is an essential feature for genetic resource conservation as well as sustainable crop production.Long-term storage induces seed viability deterioration or seed aging,accompanied by the accumulation of toxic reactive oxygen species(ROS)to suppress seed germination.Controlled deterioration treatment(CDT)is a gen-eral approach for mimicking seed aging.The transcription factor ANAC089 was previously reported to modulate seed primary germination.In this study,we evaluated the ability of ANAC089 to control seed viability during aging.Compared with that in the wild-type line,the mutation of ANAC089 significantly increased H_(2)O_(2),thereby reducing seed viability after CDT,while the overexpression of ANAC089 reduced H_(2)O_(2) and improved seed long-evity,indicating a critical role for ANAC089 in maintaining seed viability through H_(2)O_(2) signaling.A series of stu-dies have shown that ANAC089 targets and negatively regulates the level of ABI5,an important transmitter of abscisic acid(ABA)signals,to affect seed viability after CDT.Furthermore,ABI5 negatively regulated the expres-sion of VTC2,which is involved in the biosynthesis of the antioxidant ascorbic acid and H_(2)O_(2) scavenging.As a result,ANAC089 attenuates the generation of H_(2)O_(2),thereby enhancing seed viability through the ABI5-VTC2 module during the seed aging process.Taken together,our results reveal a novel mechanism by which ANAC089 enhances seed viability by coordinating ABI5 and VTC2 expression,ultimately preventing the overac-cumulation of H_(2)O_(2),which would have led to reduced seed viability.

Cloning the Promoter of BcNA1 from Brassica napus and Fad2 Gene from Arabidopsis thaliana and Construction of the Plant Expression Vector

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Biochemical and Physiological Responses of Arabidopsis thaliana Leaves to Moderate Mechanical Stimulation

Mechanical stimulation of plants can be caused by various abiotic and biotic environmental factors.Apart from the negative consequences,it can also cause positive changes,such as acclimatization of plants to stress conditions.Therefore,it is necessary to study the physiological and biochemical mechanisms underlying the response of plants to mechanical stimulation.Our aim was to evaluate the response of model plant Arabidopsis thaliana to a moderate force of 5 N(newton)for 20 s,which could be compared with the pressure caused by animal movement and weather conditions such as heavy rain.Mechanically stimulated leaves were sampled 1 h after exposure and after a recovery period of 20 h.To study a possible systemic response,unstimulated leaves of treated plants were collected 20 h after exposure alongside the stimulated leaves from the same plants.The effect of stimulation was assessed by measuring oxidative stress parameters,antioxidant enzymes activity,total phenolics,and photosynthetic performance.Stimulated leaves showed increased lipid peroxidation 1 h after treatment and increased superoxide dismutase activity and phenolic oxidation rate after a 20-h recovery period.Considering photosynthetic performance after the 20-h recovery period,the effective quantum yield of the photosystem II was lower in the stimulated leaves,whereas photochemical quenching was lower in the unstimulated leaves of the treated plants.Nonphotochemical quenching was lower in the stimulated leaves 1 h after treatment.Our study suggested that plants sensed moderate force,but it did not induce pronounced change in metabolism or photosynthetic performance.Principal component analysis distinguished three groups–leaves of untreated plants,leaves analysed 1 h after stimulation,while stimulated and unstimulated leaves of treated plants analysed 20 h after treatment formed together the third group.Observed grouping of stimulated and unstimulated leaves of treated plants could indicate signal transduction from the stimulated to distant leaves,that is,a systemic response to a local application of mechanical stimuli.

Ethylene response factor BnERF2-like (ERF2.4) from Brassica napus L.enhances submergence tolerance and alleviates oxidative damage caused by submergence in Arabidopsis thaliana

Ethylene response factor proteins play an important role in regulating a variety of stress responses in plants,but their exact functions in submergence stress are not well understood.In this study,we isolated BnE RF2.4 from Brassica napus L.to study its function in submergence tolerance.The expression of the BnE RF2.4 gene in B.napus and the expression of antioxidant enzyme genes in transgenic Arabidopsis were analyzed by quantitative RT-PCR.The expression of BnE RF2.4 was induced by submergence in B.napus and the overexpression of BnE RF2.4 in Arabidopsis increased the level of tolerance to submergence and oxidative stress.A histochemical method detected lower levels of H_2O_2,O^(·-)_2and malondialdehyde(MDA) in transgenic Arabidopsis.Compared to the wild type,transgenic lines also had higher soluble sugar content and higher activity of antioxidant enzymes,which helped to protect plants against the oxidative damage caused by submergence.It was concluded that BnE RF2.4 increased the tolerance of plants to submergence stress and may be involved in regulating soluble sugar content and the antioxidant system in defense against submergence stress.

黑腐病菌(Xanthomonas campestris)与拟南芥(Arabidopsis thaliana)品种间的致病性测定

甘蓝黑腐病菌(Xanthomonas campeatris pv.campestris)主要以十字花科植物为寄主.引起黑腐病的病原菌,是在世界范围对农业造成严重危害的病原菌之一.拟南芥(Arabidopsis thaliana)是十字花科植物,做为经典遗传学实验材料已有40多年历史.它具有较少染色体组和重复 DNA 序列,易诱变、易种植、个体小、

<i>At</i>L1 a Non-LTR Retrotrasposon Fragment in the Genome of <i>Arabidopsis thaliana </i>with Homology to Plants and Animals

We report the isolation of AtL1, a 249 bp non-LTR retrotransposon fragment from Arabidopsis thaliana by fingerprinting mRNAs extracted from A. thaliana plants, ecotype Columbia, in different heat stress conditions. Southern blot and PCR analysis suggested that AtL1 occurs as a single- or low-copy insert in the genome of A. thaliana ecotype Columbia. The presence of AtL1 in the genome of different Arabidopsis ecotypes was confirmed by PCR amplification and sequencing thus excluding all possible contamination. A preliminary scan of the AtL1 nucleotide sequence against the EMBL and NCBI databases revealed a high degree of similarity to a group of LINE type L1 retrotransposons of mammals and with a cDNA sequence of Artemisia annua. A phylogenetic analysis of LINE elements from animals and plants placed AtL1 and A. annua sequences in close proximity to some mammalian sequences but distant from the other plants LINE elements including those from Arabidopsis.

Glucosinolates and Their Hydrolysis Products in Arabidopsis thaliana Influence Performance and Feeding Choice of Pieris rapae and Spodoptera exigua

Glucosinolates and their hydrolysis products, found in plants of the order Brassicales, are well-known for their defensive properties against insect herbivores. Arabidopsis thaliana (Col-0) genetic lines with mutations that modify the type of glucosinolates (i.e. myb28myb29 and cyp79B2cyp79B3 are deficient in the production of aliphatic and indolyl glucosinolates, respectively) make it possible to test for the specific effects of these secondary chemicals on insect herbivores. The Pad3 mutant (deficient in camalexin), which has a role in resistance to pathogens, was also tested. Likewise, the effects of different glucosinolate hydrolysis products can be evaluated using genetically modified (GM) lines of the wild type Col-0 ecotype, which naturally produces isothiocyanates. These GM lines include the nitrile-producing 35S: ESP and the double knockout tgg1tgg2, which virtually lacks hydrolysis products. In both no-choice and choice experiments, the crucifer specialist Pieris rapae was virtually unaffected by differences in the type of glucosinolates or hydrolysis products. In contrast, the generalist insect Spodoptera exigua had statistically significant increases in pupae/adult weight and faster developmental times when reared on mutants deficient in the production of aliphatic and indolyl glucosinolates and their hydrolysis products. There were no differences in the performance of either insect species when reared on wild type Col-0 or Pad3. Results from feeding choice trials showed that Pieris rapae had no statistically significant preference for any of the genetic lines. In contrast, Spodoptera exigua had a significant feeding preference for the double mutant tgg1tgg2. This study provides evidence that variation in the type of glucosinolates and their hydrolysis products can influence insect performance and feeding choices, and that responses are species-specific.

Interactions of Auxinic Compounds on Ca2+ Signaling and Root Growth in <i>Arabidopsis thaliana</i>

Auxinic-like compounds have been widely used as weed control agents. Over the years, the modes of action of auxinic herbicides have been elucidated, but most studies thus far have focused on their effects on later stages of plant growth. Here, we show that some select auxins and auxiniclike herbicides trigger a rapid elevation in root cytosolic calcium levels within seconds of application. Arabidopsis thaliana plants expressing the Yellow-Cameleon (YC) 3.60 calcium reporter were treated with indole-3-acetic acid (IAA), indole-3-butyric acid (IBA), 1-naphthalene acetic acid (NAA), and two synthetic herbicides, 2,4-dichlorophenoxyacetic acid (2,4-D) and mecoprop [2-(4-chloro- 2-methylphenoxy) propanoic acid], followed by monitoring cytosolic calcium changes over a 10 minute time course. Seconds after application of compounds to roots, the Ca2+ signaling-mediated pathway was triggered, initiating the plant response to these compounds as monitored and recorded using Fluorescence Resonance Energy Transfer (FRET)-sensitized emission imaging. Each compound elicited a specific and unique cytosolic calcium signature. Also primary root development and elongation was greatly reduced or altered when exposed at two concentrations (0.10 and 1.0 μM) of each compound. Within 20 to 25 min after triggering of the Ca2+ signal, root growth inhibition could be detected. We speculate that differences in calcium signature among the tested auxins and auxinic herbicides might correlate with their variation and potency with regard to root growth inhibition.

Determining the transcriptional regulation pattern of PgTIP1 in transgenic Arabidopsis thaliana by constructing gene

The seed size, seed mass, and growth rate of transgenic Arabidopsis plants containing PgTIP1, a ginseng tonoplast aquaporin gene, are significantly higher than those of wild-type Arabidopsis plants. Whole genome expression and bioinformatics analysis, including analysis of co-expression networks and transcription factors (Tfscan), were used to determine the key genes that are activated after the expression of PgTIP1 and the transcription factors that play important roles in the regulation of the genes controlling growth of Arabidopsis thaliana seeds by using transgenic Arabidopsis plants containing PgTIP1. Differential gene analysis showed that transformation of exogenous PgTIP1 to Arabidopsis induced endogenous gene expression changes. Analysis of gene co-expression networks revealed 2 genes, PIP1 (plasma membrane aquaporin 1 gene) and RD26 (responsive to desiccation 26 gene;a NAC transcription factor), that were localized in the core of the networks. Analysis of the transcriptional regulation network of transgenic Arabidopsis plants containing PgTIP1 showed that PIP1 and RD26 were regulated via DNA binding with a finger domain on transcription factor 2 (Dof2). In this study, we demonstrated that Dof2 induces up-regulation of PIP1 and RD26 after transformation with PgTIP1. The results of this study provide a new means for conducting research into and controlling growth of Arabidopsis thaliana seeds.

Cortical Microtubule Reorientation and Its Relation to Cell Surface Texture of Epidermal Cells of Arabidopsis Thaliana Hypocotyls under Simulated Microgravity Conditions

Gravitropic curvature growth of Arabidopsis hypocotyls mainly occurred in the rapid growing Elongation Zone(EZI),not in the slow-growing Elongation Zone(EZII).By examining reorientation of Microtubules(MT)and phenotype of the cell wall in the EZI and the EZII of Arabidopsis hypocotyls under normal gravitational condition,it is found that MTs in the rapid growing epidermal cells were mainly in the transverse direction,while those in the non-growing epidermal cells were in the longitudinal directions.However,this difference in cortical MT arrays between the EZI and EZII cells disappeared when the seedlings were exposed to the simulated microgravity condition on a horizontal clinostat.Field emission scanning electron microscopy revealed that the surface texture of epidermal cells,like the direction of the MT,in the EZI and the EZII also became similar when exposed to the simulated microgravity condition.This result indicated that simulate microgravity could modify the potential differentiation between the EZI and the EZII by affecting the orientation of cortical MT in the epidermal cells.

天山北麓中段拟南芥(Arabidopsis thaliana)与相邻物种的分布格局及相互关系

天山山脉是世界拟南芥(Arabidopsis thaliana)及其近缘种的分布中心之一,资源优势明显。在北天山中段浅山地带选择拟南芥分布的典型样地50m×50m,分析了样地物种的结构、组成和土壤理化性质,用Ripley’sK(d)函数分析了拟南芥与相邻物种的空间特征和相互关系。发现样地由7科23个物种组成,以新疆绢蒿(Seriphidium kaschgaricum)为建群种,短命植物物种占近70%。拟南芥仅分布于北坡,在3m内聚集强度高于所有分析物种,在5m范围内与新疆绢蒿中株呈显著正关联,与十字花科的涩芥(Malcolmia africana)、藜科的散枝猪毛菜(Salsola brachiata)、木碱蓬(Suaeda dendroides)、角果藜(Ceratocarpus arenarius)呈一定尺度显著负关联。分析认为拟南芥空间分布依赖于新疆绢蒿大株、中株生长塑造的遮阴、保湿和丰富土壤有机质,生态位与藜科物种差异极大,生境特异性高于同属近缘种小鼠耳芥(Arabidopsis pumila),以及涩芥(M.africana)、庭芥(Alyssumdesertorum)、四齿芥(Tetracme quadricornis)、丝叶芥(Leptaleum filifolium)、狭果鹤虱(Lappula semiglabra)等短命植物。在干旱胁迫下,拟南芥环境选择强度大于种内作用,密度依赖的种子扩散表现不明显。扩散对策是通过大量生产种子,依靠果实不易开裂控制种子短距离扩散,充分利用原适宜生境来维持种群繁衍。

拟南芥(Arabidopsis thaliana)氮、碳离子注入诱变效应分析

采用N +、C +离子注入拟南芥 (Arabidopsisthaliana)种子 ,统计了种子的发芽指数 (发芽率和发芽势 ) ;用改良的RAPD技术对N+离子注入种子植株的DNA进行11个引物的随机片段多态性扩增。结果表明 ,合适剂量的N+、C+离子注入可使种子发芽率提高 ,两种离子注入种子的发芽率峰值 (分别为92.3 %和74.4 % )都在5×1014ions/cm2;分析N +离子注入材料发现 ,在1×1013 -1×1016ions/cm2剂量范围内 ,基因组DNA的变异率与发芽指数的变化趋势基本一致 ,变异率峰值 (9.0 % )在1×1015 ions/cm2。结果提示 ,分析低能N+离子诱变效应的最佳注入剂量在1×1014-5×1015 ions/cm2。对N+、C+离子注入的比较发现 ,一定范围内同等剂量C+离子注入的诱变率高于N

Transformation of Arabidopsis thaliana via Agrobacterium tumefacience with an endochitinase gene from Trichoderma, and enhanced resistance to Sclerotinia sclerotiorum

Sclerotinia sclerotiorum is an important pathogen to many crops and is especially damaging to rape in China. As a model plant Arabidopsis thaliana (Col0) was transformed by spraying Agrobacterium tumefacience with Trichoderma endochitinase gene ThEn-42 at initial bud stage. Eleven seedlings (corresponding to about 0.22 percent transformation) exhibited resistance to hygromycin. The DNA fragment unique to endochitinase (ThEn-42) was amplified by Arabidopsis leaf-PCR or genomic DNA PCR. Unfertile, dwarf and normal phenotypes appeared in the T1 generation. In addition, an enhanced resistance to S. sclerotiorum was observed. The mortality percentage (7.7% to 33.3%) in transgenic plants was significantly lower than in non-transgenic plants (86.7%) 10 days after inoculation with the pathogen.

Expression of the C-Terminal Domain of Mammalian TET3 DNA Dioxygenase in Arabidopsis thaliana Induces Heritable Methylation Changes at rDNA Loci

In plants, demethylation of 5-methylcytosine (5 mC) residues is controlled by DNA glycosylases, while in mammals it requires oxidation of 5 mC by TET proteins, a group of Fe(II)/2-oxoglutaratedependent dioxygenases. We analysed the effects of expressing the C-terminal catalytic domain of the human TET3 gene (TET3c) in Arabidopsis thaliana, using an rDNA region as a methylation reporter. In TET3c transformants, epialleles with hypomethylation or hypermethylation patterns can be induced, which is each stably retained in progeny lines even after removal of the TET3c transgene. In TET3c transformants, 5-hydroxymethylcytosine (5 hmC) marks are detected, indicative of the oxidative activity of the transgenic enzyme. 5-formylcytosine (5 fC) is only detectable in TET3c transformants with a DNA glycosylase mutant background suggesting further oxidation of 5 hmC residues to 5 fC by TET3c, and efficient recognition and removal of 5 fC by plant glycosylases. The results suggest that TET3c can be employed to induce heritable locus-specific changes in DNA methylation, and that accumulation of 5 hmC can be used as a marker for TET3c target regions.

Effects of temperature on UV-B-induced DNA damage and photorepair in Arabidopsis thaliana

DNA damage in the form of cyclobutane pyrimidine dimers(CPDs) and (6-4) photoproducts(6-4PPs) induced by UV-B radiation in Arabidopsis thaliana at different temperatures was investigated using ELISA with specific monoclonal antibodies. CPDs and 6-4PPs increased during 3 h UV-B exposure, but further exposure led to decreases. Contrary to the commonly accepted view that DNA damage induced by UV-B radiation is temperature-independent because of its photochemical nature, we found UV-B-induction of CPDs and 6-4PPs in Arabidopsis to be slower at a low than at a high temperature. Photorepair of CPDs at 24℃ was much faster than that at 0℃ and 12℃, with 50% CPDs removal during 1 h exposure to white light. Photorepair of 6-4PPs at 12℃ was very slow as compared with that at 24℃, and almost no removal of 6-4PPs was detected after 4 h exposure to white light at 0℃. There was evidence to suggest that temperature-dependent DNA damage and photorepair could have important ecological implications.

Accession-specific flowering time variation in response to nitrate fluctuation in Arabidopsis thaliana

Flowering time,a key transition point from vegetative to reproductive growth,is regulated by an intrinsic complex of endogenous and exogenous signals including nutrient status.For hundreds of years,nitrogen has been well known to modulate flowering time,but the molecular genetic basis on how plants adapt to ever-changing nitrogen availability remains not fully explored.Here we explore how Arabidopsis natural variation in flowering time responds to nitrate fluctuation.Upon nitrate availability change,we detect accession-and photoperiod-specific flowering responses,which also feature a accession-specific dependency on growth traits.The flowering time variation correlates well with the expression of floral integrators,SOC1 and FT,in an accession-specific manner.We find that gene expression variation of key hub genes in the photoperiod-circadian-clock(GI),aging(SPLs)and autonomous(FLC)pathways associates with the expression change of these integrators,hence flowering time variation.Our results thus shed light on the molecular genetic mechanisms on regulation of accession-and photoperiod-specific flowering time variation in response to nitrate availability.

QTL for floral stem lignin content and degradability in three recombinant inbred line (RIL) progenies of <i>Arabidopsis thaliana</i>and search for candidate genes involved in cell wall biosynthesis and degradability

Deciphering the genetic determinants involved in cell wall assembly is a strategic issue for breeding programs that target both ruminant feeding and biofuel production. The Arabidopsis thaliana model system has great potentials to elucidate the genetic determinants involved in cell wall component biosynthesis and those involved in the regulation cascades allowing their coordinated assembly. QTL for biomass quality related traits (cell wall content, lignin content, and cell wall degradability) were mapped in the three Arabidopsis RIL progenies Bay0 × Shahdara, Bur0 × Col0, and Blh1 × Col0. Overall, 40 QTL were detected for these traits, explaining up to 33 and 12% of the observed phenotypic variation for lignin content and cell wall degradability respectively. Major QTL hotspots were mapped on chromosome 1 (position 5 Mbp), chromosome 4 (position 1 Mbp), and chromosome 5 (position 3 Mbp). A putative candidate gene set (82 genes) was considered including those previously described as involved in cell wall phenolic component biosynthesis, their regulation factors, and genes involved in lignified tissue patterning. Colocalisations observed (according to the reference sequence of Col0) between the detected QTL and these candidate genes did not prioritize any of the three gene groups (monolignol biosynthesis, transcription factors, lignified tissue patterning). Colocalizations were thus observed for 57% of monolignol biosynthesis related genes, 55% of the transcription factors considered, and 66% of genes considered to be involved in lignified tissue patterning and assembly. Colocalizations were observed for at least one member of all investigated gene families, except WRKY transcription factors. Colocalizations were also shown with several miRNA putatively involved in the regulation of lignifying tissue assembly. Taking into account the QTL shown in the Bur0 × Col0 progeny, allelic variations were shown in the MYB32, MYB58, MYB75, GRAS SCARECROW, AtC3H14 zinc finger, SHINE2, and IFL1 genes and in the AtMIR397a. Given that the list of candidate genes is not complete, and because the QTL support intervals encompassed genes of still unknown function, it is still not clear whether one of the selected candidates is responsible for the effect of a detected QTL. Mutant investigation and positional cloning steps are likely essential to clearly determine the causal mechanism involved in cell wall degradability variation.

Comparative transcriptome analysis of atmospheric pressure cold plasma enhanced early seedling growth in Arabidopsis thaliana

The stimulatory effects of atmospheric pressure cold plasma(APCP)on plant growth have attracted much attention due to its great potential as a new approach to increase crop growth and production.However,the transcriptome changes of plants induced by APCP treatment are unknown.Herein,the comparative transcriptome analysis was performed to identify the transcriptional response of Arabidopsis thaliana seedlings to APCP.Results showed that APCP exhibited a dual effect(stimulation or inhibition)on Arabidopsis seedling growth dependent on the treatment time and the maximum stimulatory effects were achieved by 1 min APCP treatment.The metabolic analysis of amino acid,glutathione(GSH)and phytohormone demonstrated that 1 min APCP treatment decreased most amino acids concentrations in Arabidopsis seedling,while the accumulations of GSH,gibberellins and cytokinin were significantly increased.The RNA-Seq analysis showed that a total of218 differentially expressed genes(DEGs)were identified in 1 min APCP-treated seedlings versus the control,including 20 up-regulated and 198 down-regulated genes.The DEGs were enriched in pathways related to GSH metabolism,mitogen-activated protein kinase(MAPK)signaling transduction and plant resistance against pathogens.Moreover,most of the DEGs were defense,stimuli or stressresponsive genes and encoded proteins with oxidoreductase activity.Expression determination of six randomly selected DEGs by quantitative real-time PCR demonstrated similar pattern with the RNASeq data.These results indicated that the moderate APCP treatment may regulate the expression of stimuli/stress-responsive genes involved in GSH,phytohormone/amino metabolism and plant defense against pathogens via MAPK signal transduction pathway,accordingly enhance Arabidopsis seedling growth.This study provides a theoretical basis for the application of APCP in agriculture.

Induction of defence gene expression by oligogalacturonic acid requires in-creases in both cytosolic calcium and hydrogen peroxide in Arabidopsis thaliana

Responses to oligogalacturonic acid (OGA) were determined in transgenic Arabidopsis thaliana seedlings expressing the calcium reporter protein aequorin. OGA stimulated a rapid, substantial and transient increase in the concentration of cytosolic calcium ([Ca2+]cyt) that peaked after ca. 15 s. This increase was dose-dependent, saturating at ca. 50 μg Gal equiv/ml of OGA. OGA also stimulated a rapid generation of H2O2. A small, rapid increase in H2O2 content was followed by a much larger oxidative burst, with H2O2 content peaking after ca. 60 min and declining thereafter. Induction of the oxidative burst by OGA was also dose-dependent, with a maximum response again being achieved at ca. 50 μg Gal equiv/mL. Inhibitors of calcium fluxes inhibited both increases in [Ca2+]cyt and [H2O2], whereas inhibitors of NADPH oxidase blocked only the oxidative burst. OGA increased strongly the expression of the defence-related genes CHS,GST, PAL and PR-1. This induction was suppressed by inhibitors of calcium flux or NADPH oxidase, indicating that increases in both cytosolic calcium and H2O2 are required for OGA-induced gene expression.

不同栽培密度下拟南芥(Arabidopsis thaliana)的形态分析

为初步阐明双子叶植物响应栽培密度变化的规律,本研究以模式植物拟南芥(Arabidopsis thaliana)为材料,设置不同栽培密度(1×1、2×2、3×3、4×4、5×5、6×6、7×7)进行盆栽试验,分析不同栽培密度下拟南芥不同生长时期的形态指标变化规律。结果表明:(1)在同一栽培密度处理下,随着拟南芥的生长发育,其株高、茎长和根长逐渐增加,莲座叶直径逐渐增加直至稳定,叶面积先增大后减小,顶部分枝数和基部分枝数逐渐增加或逐渐增加直至稳定。在同一生长时期,拟南芥个体大小随着栽培密度增加而减小,且高栽培密度下抽薹和开花时间提前。(2)不同栽培密度对拟南芥株高、茎长、根长、莲座叶直径、顶部分枝、基部分枝和叶面积均存在显著影响。随着栽培密度的增加,拟南芥株高、茎长总体呈降低趋势,根长呈逐渐增加趋势,莲座叶直径、顶部分枝数和基部分枝数呈逐渐减小趋势,叶面积表现为先增大后减小或逐渐减小趋势。本试验从形态上初步阐明了拟南芥响应栽培密度变化的规律,栽培密度对不同生长时期拟南芥各形态指标均产生了显著影响,该结果可为通过合理密植调控双子叶植物形态提供理论依据。