Physiologia plantarum最新文献

Prunus mume, the only plant in the genus Prunus of the Rosaceae family with a distinctive floral scent, can release a large number of aromatic substances into the air when it blooms. Among these, benzyl acetate has been recognized as a characteristic aromatic substance. In this study, we extracted and analyzed the change in volatility and endogenous content of benzyl acetate using the 'Caizhiwufen' P. mume flowers. The volatile compounds of the paraxial abaxial surfaces and inner and outer petals were detected by gas chromatography-mass spectrometry (GC-MS). We analyzed the expression patterns of the ABCG subfamily, compared the volatilization efficiencies in spatial and temporal differences, and hypothesized PmABCG2, 9, 11, and 16 that were associated with the transmembrane transport of benzyl acetate. We then cloned the above candidate genes, constructed the pTRV2-PmABCGs gene silencing vectors, and transiently infiltrated P. mume via vacuum infiltration. The volatile amount of benzyl acetate was significantly decreased, and endogenous content was higher than that of the control, which preliminarily verified that PmABCG9 could transport benzyl acetate. Finally, we incubated tobacco plants with exogenous benzyl acetate, benzyl alcohol, and leaf acetate and found that PmABCG9 specifically selected benzyl acetate as a substrate. The results of this study could support the hypothesis that PmABCG9 could effectively promote the volatilization of benzyl acetate and elucidate the transmembrane transport mechanism of benzyl acetate in P. mume.

Toona sinensis, a plant species renowned for its culinary and medicinal properties, exhibits diverse colour variations that contribute to its aesthetic appeal and commercial value. Understanding the molecular mechanisms underlying colour and aroma traits in Toona sinensis is crucial for breeding programs and quality regulation in agriculture and the food industry. The present investigation included a comprehensive analysis of the transcriptomic and metabolomic profiles of Toona sinensis with different colours, including green, red, and red leaves with green stems. Metabolic analysis revealed that the flavonoid biosynthesis pathway governs the colour distinction between green and red Toona sinensis. The top 10 metabolites influenced by transcriptome include terpenoids (5), heterocyclic compounds (1), phenol (1), ketone (1), aldehyde (1), and alcohol (1). Fifteen highly expressed genes impacted by phenylpropanoid, sesquiterpenoid, and triterpenoid biosynthesis in coloured Toona sinensis. Functional annotation and pathway analysis revealed that terpene metabolites are predominantly synthesized via terpene metabolic pathway, involving eight key gene families. This study underscores the importance of multi-omics approaches in unravelling the genetic and metabolic basis of phenotypic traits in plant species aimed at improving colour, aroma, and nutritional quality in plants and derived products. HIGHLIGHTS: Flavonoid biosynthesis pathway governs the colour distinction between green and red Toona sinensis. The top 10 metabolites influenced by transcriptome include five terpenoids, one heterocyclic compound, one phenol, one ketone, one aldehyde, and one alcohol. Fifteen highly expressed genes impacted by phenylpropanoid, sesquiterpenoid, and triterpenoid biosynthesis in coloured Toona sinensis. Terpene metabolites are predominantly synthesized via the terpene metabolic pathway, involving eight key gene families. The net photosynthetic rate and intercellular CO₂ concentration are relatively high in the red Toon sinensis morph.

Grafting can promote the growth and nitrogen use efficiency (NUE) of cucumber seedlings under reduced nitrogen (N) application, however, its underlying mechanisms and effects on mature plants remain unknown. For this purpose, self-grafted and rootstock-grafted cucumber plants were treated with two N levels (7 and 4 mM) throughout the entire growth period. The long-term reduced-N treatment significantly limited the growth, root morphology, nitrate (NO₃ ^-) uptake, NUE traits, photosynthesis, phenylalanine ammonia-lyase (PAL) activity, yield, and fruit quality of self-grafted plants but had no influence on rootstock-grafted plants, it even improved their NUE traits, total phenolic and flavonoid contents, and PAL activity. Furthermore, the expression of the NRT1.2, NRT1.5, NRT2.2, and NRT2.5 genes were significantly down-regulated in self-grafted plant roots, while they and the transcription factors NLP6 and LBD38 were up-regulated in rootstock-grafted plant roots under reduced-N environments. Correlation analysis showed that plant growth, root surface area, N-accumulation, N-uptake efficiency (NUpE), NUE, photosynthesis, PAL activity, yield, and fruit quality were all positively correlated with each other; meanwhile, the root morphology, NRT1.2 and NRT2.1 gene expression were all positively correlated with NUpE and NUE. The results demonstrate that under reduced-N application, rootstock grafting can enhance NO₃ ^- uptake and N accumulation to improve the NUE of cucumber plants and resist reduced-N environment through secondary metabolism, maintaining growth, photosynthesis, yield, and fruit quality without adverse effects. The up-regulation of NRT genes and related transcription factors regulates the NO₃ ^- uptake in rootstock-grafted plants. Rootstock grafting will be beneficial for fertilizer conservation and efficient cucumber production. yield and fruit quality.

Wheat responses to F. graminearum result in a deep and sharp reprogramming of a wide range of biological processes, including energy-associated functions and related metabolisms. Although these impacts have been thoroughly described at the molecular scale through proteomics and transcriptomics studies, phenotypic studies are still needed to fill the gap between the observed molecular events and the actual impacts of the disease on the ecophysiological processes. Taking advantage of the gas exchange method, the effects of two F. graminearum strains of contrasting aggressiveness on spike's photosynthesis and respiration-associated processes during an early infection time course were deeply characterized. Besides, an RNAseq-based expression profiling of the genes involved in the photosynthesis, respiration and stomatal movement processes was also performed when plants were challenged using the same two fungal strains. In response to Fusarium head blight, CO₂ assimilation and CO₂ diffusion adjustments matched transcriptomic data, showing altered photosynthetic processes and sharp gene regulations unrelated to symptom development. In contrast, although ecophysiological characterization clearly demonstrated respiration adjustments along with the F. graminearum's infection process, the gene regulations involved were not fully captured transcriptionally. We demonstrated that combining gas exchange methods with transcriptomics is especially effective in enhancing and deepening our understanding of complex physiological adjustments, providing unique and complementary insights that cannot be predicted from a single approach.

Zinc is an essential trace element for plant growth and development. Zinc transporters play an important role in regulating zinc homeostasis in plants. In this study, the potato cultivar 'Atlantic' was used as experimental material to analyze the expression characteristics of the StZIP2 gene in different potato tissues under zinc deficiency stress. Transgenic plants with overexpression and interference expression of the StZIP2 gene were obtained by genetic transformation and treated with zinc deficiency stress. Chlorophyll content, antioxidant enzyme activity, proline (Pro) and malonic dialdehyde (MDA) content, zinc content in aboveground parts and roots, and root indices were determined. The results showed that the expression level of the StZIP2 gene in roots, stems and leaves under zinc deficiency stress was significantly higher than that of the control, and the expression level of the StZIP2 gene in roots under zinc deficiency stress was the highest. After zinc deficiency treatment, the content of chlorophyll and Pro, the activity of catalase (CAT), peroxidase (POD), superoxide dismutase (SOD), root-to-shoot ratio, root length and root fresh weight of overexpressed plants were significantly increased, while the MDA content was significantly decreased. The ratio of zinc content between the above-ground part and the root of the overexpressed plants was significantly higher than that of the non-transgenic plants, and the transport efficiency from the root to the above-ground part was significantly increased in the overexpressed plants, whereas it was just the opposite in the interference expressing plants. The result provides basic data to further elucidate the StZIP2 gene function.

The increasing impacts of climate change and intensified human activities exacerbate soil salinization, posing significant challenges to agricultural productivity. Therefore, addressing salt stress in crops is a critical area of research. In this study, strawberry seedlings (Fragaria×ananassa Duch. 'Benihoppe') were used to investigate the alleviating effects of hydrogen-rich water (HRW) on salt stress through integrated transcriptomic and metabolomic analyses. HRW treatment was found to significantly enhance plant growth, notably increasing root biomass by 49.50%. Additionally, HRW modulated key parameters, including the levels of soluble sugars, malondialdehyde (MDA), and antioxidant enzyme activities, while promoting K⁺ uptake and Na⁺ exclusion. Transcriptomic analysis revealed that HRW induced the expression of genes associated with ion transport, antioxidant defence, and cell wall biosynthesis in roots. Metabolomic profiling identified phenolic acids, flavonoids, and amino acids as critical metabolites in HRW-mediated salt stress mitigation. Integrated multi-omics analysis highlighted two key metabolic pathways, phenylpropanoid biosynthesis and amino and nucleoside sugar metabolism, pivotal to the observed protective effects. This study provides molecular insights into the mechanisms by which HRW alleviates salt stress in strawberry seedlings, underscoring the potential of hydrogen gas applications in sustainable agriculture.

Reduced height (Rht) genes have revolutionised wheat cultivation, but they can compromise freezing tolerance, and only a few alleles are in use. Thus, evaluating the role of other Rht alleles in stress responses is crucial. Far-red supplementation of white light (W+FR) can induce pre-hardening in cereals at 15°C. However, the relevant effect of blue light enrichment (W+B) is poorly described. This study investigates the influence of W+FR or W+B exposure in young winter wheat leaves of a tall (wild-type, rht12) and a dwarf, gibberellin-deficient (near-isogenic line, Rht12) genotype in cv. Maris Huntsman background over 10 days at 15°C. The main objectives were to investigate the relationship between light quality, gibberellin homeostasis, and freezing tolerance. Key parameters such as frost injury, hormonal pools and the expression of relevant genes were examined. Results provided evidence about the involvement of Rht alleles in the basal freezing tolerance of wheat leaves from the side of gibberellin availability. It was revealed that W+FR and W+B treatments partially rescued the freezing-sensitive phenotype of Rht12 leaves, suggesting a potential compensatory mechanism. Analysis of gibberellic acid (GA) metabolism indicated differential responses to light treatments between the Rht12 and wild-type leaves, with implications for freezing tolerance. Moreover, alterations in hormone levels, including jasmonic acid (JA) and salicylic acid (SA), were observed, highlighting the complex interplay between light signalling and hormonal regulation in wheat. Overall, these findings suggest that manipulating light responses may offer a strategy to enhance freezing tolerance in gibberellin-deficient dwarf wheat genotypes.

Bermudagrass [Cynodon dactylon (L.) Pers.] is widely used for soil remediation, livestock forage, and as turfgrass for sports fields, parks, and gardens due to its resilience and adaptability. However, low temperatures are critical factors limiting its geographical distribution and ornamental season, even preventing its safe overwintering. PHYTOCHROME-INTERACTING FACTOR 4 (PIF4) acts as a hub transcription factor, not only regulating various light responses but also integrating multiple external stimuli to improve plant productivity and architectural adaptation under adverse stress conditions, which makes it potential as a target gene. In this study, we cloned and characterized the CdPIF4 genes in bermudagrass. Expression analysis revealed that it is predominantly expressed in leaves and is regulated by photoperiod and cold stress. Using Agrobacterium-mediated genetic modification, we successfully generated CdPIF4a-overexpressing bermudagrass lines. Under cold stress at 4°C, these transgenic plants demonstrated enhanced cold tolerance, as indicated by higher relative water content, reduced membrane damage, and lower levels of lipid peroxidation levels. Photosynthetic analysis revealed that CdPIF4a-overexpressing plants exhibited higher light energy capture and transfer efficiency at this low temperature, with less energy loss. Additionally, they showed higher antioxidant enzyme activity and lower levels of reactive oxygen species levels. The responsive regulation of cold stress-related genes further validated the role of the CdPIF4a gene in enhancing cold tolerance. This study elucidates that CdPIF4 enhances cold tolerance in bermudagrass through physiological and molecular mechanisms, offering new insights and valuable genetic resources for advancing cold resistance research in bermudagrass and other grass species.

It is known that red light irradiation enhances the biosynthesis of (E)-β-caryophyllene in plants. However, the underlying mechanism connecting red light to (E)-β-caryophyllene biosynthesis remains elusive. This study reveals a molecular cascade involving the phyB-PIF4-MYC2 module, which regulates (E)-β-caryophyllene biosynthesis in response to the red light signal in Arabidopsis thaliana. In this module, phyB positively regulates (E)-β-caryophyllene biosynthesis under red light, whereas PIF4 negatively regulates it; both regulations require the involvement of MYC2, a transcription factor that can bind directly to the promoter of the TPS21 gene which encodes (E)-β-caryophyllene synthase. Importantly, protein-protein and protein-DNA interaction assays show that PIF4 reduces the binding affinity of MYC2 to the TPS21 promoter through direct interaction with MYC2. We propose that the phyB-PIF4-MYC2 module represents a universal mechanism linking red light to sesquiterpene biosynthesis in plants.