Acta Physiologiae Plantarum最新文献

The regulatory functions that jasmonic acid (JA) and salicylic acid (SA) play in physiological processes when plants are subjected to water deficiency is not well understood currently. Therefore, this study was devised to analyze the regulatory role and antagonistic interactions between JA and SA that may ultimately play a role in mitigating drought stress. Experimental Rosa damascena plants were harvested at three different time points after having been subjected to 25%, 50% or 100% of the soil water holding capacity (WHC), utilizing R. damascena. The stomatal aperture was reduced greatly in JA-treated plants cultivated in simulated severe drought stress conditions; however, this reduction in stomata aperture was significantly restored upon exogenous application of SA. Additionally, SA applied to JA-treated, drought-stressed plants modulates proline content in both roots and shoots. Finally, the reduction of the total chlorophyll content was mediated by disruption of the stomata aperture, the augmented levels of antioxidant enzyme activity, and the proline content in JA-treated plants subjected to severe drought stress were all mitigated via the exogenous application of SA, suggesting that SA may modulate JA-induced stomatal closure, even under drought condition.

Methyl jasmonate (MeJA), a signal molecule, plays an essential role in growth, development and defense responses in various plants. However, its role in ryegrass in the response to salt (NaCl) and/or cadmium (Cd) stress remains poorly understood. In this study, the role of exogenous MeJA in alleviating NaCl and Cd-induced toxicity in ryegrass was investigated. According to the results, MeJA application increased the shoot dry weight in NaCl, Cd, Cd + NaCl stressed ryegrass by 5.66%, 7.49% and 12.84%, meanwhile, the root dry weight increased by 12.59%, 4.87% and 13.85%, respectively. Besides, MeJA significantly increased the chlorophyll and carotenoid content in leaves of the stressed ryegrass. It also resulted in lower levels of H₂O₂, O₂⁻ and MDA accumulation via enhancing the antioxidant contents (AsA, GSH, total phenols and flavonoids) and antioxidant enzymes (POD, CAT, APX) activities. Moreover, foliar application of MeJA elevated the soluble protein, soluble sugar content and stimulated mineral nutrient (Mg, K, Ca, Fe, Cu and Zn) uptake while decreased Na⁺ and Cd²⁺ accumulation. Therefore, MeJA could help to alleviate salt and/or Cd induced toxicity in ryegrass and act as a helpful tool for improving plant performance under salt and/or Cd stress.

Autophagy plays an important role in regulating the development of rice endosperm cells. In this study, to investigate the possible relationship between ascorbic acid (Asc) and autophagy in the process of rice endosperm development, we hypothesized that altered endogenous Asc levels would influence autophagic activity, thereby affecting nitrogen remobilization and grain quality in rice. To test this, the distribution and number of autophagosomes/autophagy-related structures in mesophyll cells and endosperm cells, the gene transcript abundances related to senescence and autophagy, and the enzyme activity and gene transcript abundances related to nitrogen metabolism were analyzed. The results showed that the altered levels of Asc lead to a change in the expression of senescence and autophagy associated genes, and Asc deficiency decreases the number of autophagosomes/autophagy-related structures in rice leaf mesophyll and endosperm cells, while higher Asc level increases them. Meanwhile, Asc also affects the nitrogen metabolism in rice grains by affecting the activities of key enzymes for nitrogen metabolism.

Integrating foreign gene into a plant’s genome through genetic engineering can lead to insertion, deletion, and re-arrangement phenomena, potentially causing unintended effects in transgenic plants. This research endeavor aimed to compare the phenotypic characteristics and chemical compositions observed in the shoots of Bt- transgenic potato lines (Solanum tuberosum L.). The primary goal of this study was to assess whether any unintended changes have occurred as a result of genetic transformation in plants when compared to their non-transgenic counterparts. A correlation was discerned between the cry1Ab transcript level and Cry1Ab protein content during various phases of the plant growth. However, no marked association was detected between the copy number of the gene and the level of its protein expression. The phenotypic assessment showed differences between transgenic and non-transgenic lines, which may be due to somaclonal variations, a common occurrence during tissue culture in potato genetic transformation. Moreover, the expression of recombined proteins and the insertional effects of the transgenes may have contributed to unintentional variations in composition and phenotypic characteristics between transgenic and non-transgenic control line. Despite significant differences in amino acid levels between transgenic and non-transgenic potato plants, all changes in the metabolite levels fell within the acceptable range for potato cultivars. Hence, the chemical composition of the genetically modified potato plants was equivalent to their non-transgenic counterpart. In conclusion, the results indicated that transgenic potato lines are as safe as non-transgenic control plants.

Effective water management in crops with high water requirements, such as rice, demands research to establish accurate irrigation systems for sustainable use of resources and ensuring feeding the world’s population at the same time. This research investigated how both bulk and nanoparticles forms of chitosan (Ch) and silicon (Si) on rice performance under delayed-flooding irrigation. The experiment involved applying foliar treatments of distilled water (control), Ch (0.05% w/v), nano-Ch (NCh; 0.05% w/v), Si (0.05% w/v), nano-Si (NSi; 0.05% w/v) and NCh-NSi (0.1% w/v) to 25 days old plants. The plant cultivation was carried out using a two-stage irrigation approach. Initially, for the first 40 days, the plants were irrigated to saturation. Then, a permanent flooding regime was established starting 40 days after sowing. Various plant traits including culm characteristics (wall thickness, major vascular bundle area, and thickness of mechanical and parenchyma layers), leaf features (thickness, length and dry mass) and grain characteristics (filled spikelet, and dry mass, length and number of fertile panicle) were enhanced under various treatments. Further, foliar treatments increased photosynthetic pigments, phenols, flavonoids, anthocyanins, carbohydrates, protein, proline, activity of catalase and ascorbate peroxidase, and total antioxidant activity. Overall, the bulk and nano-forms of Ch and Si improved rice-cropping system in the delayed-flooding conditions, with the highest yield achieved in NCh-NSi treatment. In conclusion, eco-friendly chitosan nanoparticles combined with Si offer a promising approach to boost crop yield and improve water resource management, especially in the face of climate change and water scarcity.

Adventitious root (AR) formation is a complex developmental response modulated by a network of phytohormones. While auxins such as indole-3-acetic acid (IAA) are well-established drivers of AR induction, emerging evidence highlights the involvement of jasmonates in regulating wound-induced and stress-related developmental programs. This study investigates the temporal dynamics of selected auxins (IAA, IAA-Asp) and jasmonates (jasmonic acid, JA, and its bioactive conjugate JA-Ile) during the early phase of AR formation in leafy cuttings of Prunus subhirtella ‘Autumnalis’. Hormonal profiling was conducted in the basal (rooting) region of cuttings at seven time points (0 min, 15 min, 30 min, 45 min, 2 h, 4 h, and 24 h) following severance. In addition, jasmonate dynamics were evaluated in the apical, unwounded part of the same cutting—specifically, shoot tip including developing leaves. The results revealed rapid, transient peaks of JA and JA-Ile in both tissues within the first few hours post-wounding, followed by a delayed but progressive accumulation of IAA and IAA-Asp in the basal region. This tissue-specific and temporally offset hormonal pattern suggests that JA-related wound signaling may precede and potentially facilitate auxin accumulation required for root induction. Overall, this study establishes Prunus subhirtella ‘Autumnalis’ as a valuable woody model for investigating hormone-mediated adventitious root formation and provides a framework for exploring interhormonal crosstalk in vegetative propagation.

Ethylene responsive factors (ERFs) play pivotal roles in regulating plant response to environmental stresses. An increasing body of studies have been published on characterizing the function of ERFs in plants. However, there are very few reports regarding stress-related ERF proteins available in tomato. Here, the function of SlAP2e, a nucleus-localized transcription factor from tomato, in plant immune response against pathogens was characterized. Expression of SlAP2e could be induced by MeJA, ACC and SA. Transcriptional activation assays using yeast two-hybrid system demonstrated that SlAP2e functions as a transcriptional activator in yeast. Ectopic expression of SlAP2e in Arabidopsis confers increased resistance to necrotrophic fungus Botrytis cinerea but decreased resistance to hemibiotrophic bacteria Pseudomonas syringae pv. tomato DC3000. SlAP2e transgenic plants showed improved ROS-scavenging ability under H₂O₂ stress. Real-time RT-PCR results indicated that pathogenesis-related (PR) genes (AtPR1 and AtPR5) respond differentially to Botrytis cinerea and Pseudomonas syringae pv. tomato DC3000. All research data demonstrate that SlAP2e acts as an immune regulator that may endow the plants with differential responses to necrotrophic and biotrophic pathogens in Arabidopsis. SlAP2e can have potential beneficial effects in the genetic improvement of economically important crops.

To distiguish Acanthopanacis Cortex from its analogues, and to screen suitable DNA barcodes, the ITS2 and its secondary structure, matK and psbA-trnH were used. A total of 74 sequences encompassing 6 taxa representing Acanthopanacis Cortex and its analogues were collected from its main distributing area and GenBank. Samples were assessed by PCR amplification, sequencing, sequence quality, extent of specific genetic divergence, DNA barcoding gap, and the ability to discriminate between species. The results of NJ trees based on the three DNA barcodes showed that all the species could be distinguished from each other and branched independently, showing good monophyly. The topological structure of ITS2 PNJ phylogenetic tree was consistent with that of NJ tree. The interspecific genetic distance between Acanthopanacis Cortex and its analogues was significantly greater than the intraspecific genetic distance. The secondary structure of ITS2 was significantly different among species. All the three DNA barcodes could be used as molecular marker to differentiate Acanthopanacis Cortex from its analogues, however the intergeneric identification efficiency was the best in ITS2, followed by matK and psbA-trnH. Therefore, ITS2 as the dominant identification method supplemented by matK and psbA-trnH DNA barcodes are recommended in this study to provide scientific basis for Acanthopanacis Cortex identificationand safety of clinical use.

Tropical Capsicum chinense is known for its strong leaf cooling capacity and stomatal responsiveness under high-temperature conditions. To better understand whole-plant acclimation strategies, we examined leaf-level physiological responses—including stomatal behavior and water potential under atmospheric stress based on combinations of temperature and humidity. Particular attention was given to signaling mechanisms beyond conventional VPD-based models and age-dependent differences in leaf responses. Under high-temperature and low-humidity conditions, transpirational cooling was markedly enhanced, lowering leaf surface temperature by up to 6.3 °C. This cooling effect contributed to the maintenance of high leaf water potential across canopy layers and sustained photosynthetic activity. In contrast, under moderate temperature and low humidity, stomatal closure occurred despite low intercellular CO₂ concentrations, suggesting the involvement of humidity-specific signaling mechanisms. Additionally, leaf age influenced stress sensitivity, with lower-position leaves showing greater vulnerability to senescence and water imbalance. These findings demonstrate that temperature and humidity act interactively to shape leaf water regulation and stomatal behavior. The results provide new insights into plant physiological adaptation under atmospheric stress and contribute to the refinement of stomatal response models and climate-resilient crop management strategies.

This research aimed to evaluate the effects of carbon dots on the physiological parameters of sesame. Carbon dots were prepared by hydrothermal treatment of Gum Tragacanth and characterized by TEM, FTIR, and XRD. Then the sesame treatment with concentrations of 0 (control), 5, 10, and 20 mg/L of carbon dots was carried out. Our data revealed that in the germination stage, the radicle length in all treatments, the seedling fresh weight in the concentration of 10 mg/L, and the amount of chlorophyll a and b in the concentration of 5 mg/L of carbon dots were significantly increased. In the hydroponic stage, the root fresh weight at a concentration of 20 mg/L of carbon dots was significantly increased. The highest amount of phenol, flavonoid, total carbohydrates, and total protein in the leaf, and phenol, flavonoid, and antioxidant capacity in the root was behold in the treatment with a concentration of 5 mg/L of carbon dots. The highest level of total protein in the root, and chlorophyll a, b, and total carotenoid were observed in a concentration of 10 mg/L of carbon dots. The activity of superoxide dismutase (SOD) in root and Ascorbate peroxidase (APX) in leaf and root in all treatments and the activity of catalase (CAT) in leaf and root at a concentration of 5 mg/L of carbon dots were significantly increased. It seems that low concentrations of carbon dots could be effective in improving physiological parameters of the sesame and therefore it is suggested as a suitable growth stimulant.