Planta最新文献

Main conclusion: Nitrogen (N) deficiency in maize modulates carbon (C) and N metabolism by enhancing biomass allocation towards vegetative organs, suppressing sucrolytic activity and gene expression, inhibiting ear sink strength and increasing vegetative competition for assimilates, and causing C accumulation in developing maize ears due to inefficient C utilization. Nitrogen (N) form influences carbon (C) and N metabolism, thereby shaping maize growth and development. However, the mechanisms modulating C assimilate allocation to ears under different N forms remain unclear. This study investigated C metabolism and spatial distribution in the mini maize line TX-40 J, supplied with four N treatments: 1 mM NO₃⁻ (low N, LN), 2 mM NO₃⁻ (medium N, MN), 10 mM NO₃⁻ (high N, HN), and 1 mM NH₄⁺ (low ammonium, LA). LN significantly reduced shoot and ear biomass, producing smaller cobs, while stimulating root proliferation and increasing shoot-to-ear (S/E), root-to-ear (R/E), and root-to-shoot (R/S) ratios. Maize developing ears under LN accumulated less carbohydrates (sucrose, glucose, fructose, starch) and exhibited reduced activities of key enzymes (SPS, SuSy, SS, CINV, VINV, AGPase). Diurnal and spatial analysis showed impaired assimilate translocation, with sugars and starch significantly retained in source tissues. Gene expression analyses showed that genes involved in sucrose metabolism and transporter genes (ZmSPS, ZmSuSy, ZmCINV, ZmSWEET, ZmSUT), and starch biosynthetic genes (ZmAGPase, ZmSS) were differentially regulated by N treatments in developing ear tissues. Compared with HN, MN and LA plants, LN-treated plants exhibited markedly lower expression of these genes, suggesting reduced carbohydrate synthesis and impaired sink allocation under N deficiency. Correlation analysis further linked increased vegetative-to-reproductive ratios with reduced nutrient deposition in ears. Collectively, LN triggered metabolic reprogramming that supported vegetative retention over reproductive investment, weakening sink strength and yield potential. These findings provide mechanistic insight into N form-dependent regulation and inform strategies to improve nutrient use efficiencies.

Main conclusion: We integrate recent mechanistic advances to define CSN as a central regulatory hub coordinating deneddylation, signaling, transcription, and stress responses across plant developmental and immune pathways. The CSN (COP9 signalosome) is an evolutionarily conserved multiprotein complex initially identified in Arabidopsis thaliana as a negative regulator of photomorphogenesis. Subsequent studies across diverse organisms have revealed that CSN plays central roles in a wide array of biological processes, including protein degradation, hormone signaling, stress adaptation, development, and immunity. The CSN exerts its core function through deneddylation of cullin-RING E3 ubiquitin ligases, thereby regulating protein turnover via the ubiquitin-proteasome system. In plants, CSN integrates external signals such as light and pathogens to fine-tune developmental programs and defense responses. Recent research highlights its regulatory functions in secondary metabolism, flowering time, reactive oxygen species homeostasis, and stress-induced epigenetic memory. Additionally, pathogens have evolved effectors to hijack CSN-mediated processes to suppress host immunity. This review focuses specifically on the multifunctional roles and regulatory mechanisms of CSN in plants, highlighting novel insights into its emerging roles in transcriptional and epigenetic regulation. Unlike previous summaries, we integrate recent mechanistic advances and cross-kingdom perspectives to provide a comprehensive framework for understanding CSN as a central node in the dynamic regulation of eukaryotic cellular functions.

Main conclusion: Antarctic plants employ distinct cold acclimation strategies: Deschampsia antarctica uses general membrane-chloroplast stabilization while Colobanthus quitensis relies on chloroplast-focused tolerance mechanisms. The two native vascular plants of Antarctica, Deschampsia antarctica and Colobanthus quitensis, persist in one of the most extreme terrestrial environments on Earth, where episodic freeze-thaw cycles are frequent even during the growing season. Survival under such conditions necessitates not only tolerance to freezing alone but also effective recovery from freeze-induced injuries-a composite trait referred to as freeze-thaw stress tolerance (FTST). Yet, estimates of FTST of Antarctic plants have remained inconsistent across studies, largely due to methodological differences in freezing regimes and injury assessment metrics. Here, we employed a standardized, ice-nucleation-controlled freeze-thaw protocol and assessed FTST using two independent physiological indicators: electrolyte leakage (membrane integrity) and chlorophyll fluorescence (Fv/Fm; PSII function). We further validated the LT₅₀ values-the temperature causing 50% injury-through post-thaw recovery (PTR) assays, and examined total soluble sugar dynamics as a metabolic indicator of recovery capacity. D. antarctica exhibited coordinated enhancements in both membrane and chloroplast resilience following cold acclimation, with LT₅₀ values from both metrics closely aligned. In contrast, C. quitensis demonstrated a chloroplast-centered acclimation strategy, characterized by pronounced improvement in Fv/Fm-based LT₅₀, while electrolyte-leakage based estimates remained largely unchanged. PTR results and sugar profiling supported the biological relevance of Fv/Fm as a more reliable FTST marker in C. quitensis. Together, these findings reveal distinct, species-specific acclimation frameworks to freeze-thaw stress; a global stabilization strategy in D. antarctica and a chloroplast-focused tolerance mechanism in C. quitensis, underscoring divergent evolutionary pathways for polar plant survival.

Main conclusion: Chilling injury severely threatens postharvest produce; integrating physical, chemical, biological, and genetic strategies with advanced diagnostics offers sustainable solutions to enhance cold tolerance, extend shelf life and ensure food security. Chilling injury, caused by exposure to suboptimal temperatures, leads to membrane damage, oxidative stress, and metabolic disruptions resulting in visible symptoms such as discoloration, pitting, and spoilage. This condition severely affects the quality, shelf life, and marketability of tropical and subtropical produce, posing significant challenges during storage and transportation. This review examines the underlying mechanisms of chilling injury, along with advancements in diagnosis and mitigation strategies. Diagnostic methods range from traditional visual inspections to modern tools such as spectroscopy, molecular biomarkers, and thermal imaging, enabling early detection of chilling injury. Mitigation strategies are classified into physical approaches (controlled storage conditions, preconditioning), chemical treatments (antioxidants, phytohormones), and biological interventions (genetic engineering, biostimulants). While these methods show promise, challenges such as scalability, crop-specific applicability, and universal effectiveness persist. Emerging molecular and genetic techniques offer potential solutions but require further validation and careful consideration of ecological and regulatory implications. By addressing existing gaps in research and practice, this review details the above stated approaches and emphasizes the importance of integrative approaches that combine physical, chemical, and biological strategies. Such comprehensive efforts are crucial for reducing postharvest losses, enhancing produce resilience, and promoting food security through sustainable agricultural practices.

Main conclusion: Perennial desert dominant species Haloxylon ammodendron exhibits three distinct morphological diaspores that differ in protein content among polymorphic fruits drives divergence in germination traits, likely forming a bet-hedging ecological adaptation strategy to cope with extreme environmental heterogeneity in desert ecosystems. Fruit polymorphism, the production of multiple fruit morphotypes within a species, is an adaptive bet-hedging strategy in variable environments. However, researches about perennial plant and the adaptive mechanisms are not well understood. Haloxylon ammodendron, a constructive desert shrub, exhibits three fruit morphotypes: YY (yellow wings with yellow pericarp), YP (yellow wings with pink pericarp), and PP (pink wings with pink pericarp). We investigated their ecophysiological and molecular mechanisms through germination assays under salt and drought stress, combined with proteomic analysis. YP consistently showed the highest germination percentage (GP) and germination rate index (GRI) under stress, while PP displayed well germination success under low salinity and well-watered conditions (GP = 32.7%, 36.7%; GRI = 0.018, 0.020), but significantly impaired viability under stress (GP = 12.7%, 12.0%; GRI = 0.006, 0.006). Proteomics identified 721 differentially accumulated proteins, with the most (662) between YP and PP, linked to stress response and germination. YP's high abundance of stress-resistant proteins enabled rapid germination, whereas PP's delayed germination aligns with a persistent seed bank strategy. This polymorphism promotes niche differentiation: YP ensures quick colonization, PP enhances long-term resilience, and YY offers an intermediate strategy. Our findings reveal molecular-ecological adaptations in H. ammodendron, aiding targeted germplasm use for desert restoration.

Main conclusion: This study links rice leaf metabolome to yield traits, identifying 13 key metabolites through computational metabolomics. These enable early prediction of high-yield varieties, enhancing screening strategies in crop breeding. Metabolites serve as dynamic indicators of plant phenotype, linking genotype and environment through metabolomics profiling. Here, we used a computational metabolomics approach to correlate leaf metabolites with yield traits in four indica rice varieties. Dani Gora, with the highest yield, showed distinct phenotypic and metabolic profiles compared to Njavera N96. Analysis of robust non-redundant mass features revealed maximal 'metabotype' and trait differences between these two varieties. Dani Gora displayed higher central metabolism diversity, while Njavera N96 showed elevated specialization in secondary metabolism. Comparative pathway impact analysis identified 14 central metabolites, especially involved in six metabolic pathways, significantly enriched and positively correlated with the yield parameters. Machine learning (Random Forest) and fold change analysis finally validated 13 key metabolites predictive of yield traits. This framework demonstrates how leaf metabolite classifiers can enable early, high-throughput screening for high-yield rice varieties, offering a tool for accelerating rice breeding strategies.

Main conclusion: OsPP2C10, a member of the OsPP2C subclass F2, is localized at the endoplasmic reticulum exit sites and interacts with vesicle trafficking components, OsSAR1C and an OsPHYTOLONGIN. Altered accumulation patterns of TLP and GLU2 proteins in the apoplast of OsPP2C10 knockout, knockdown, and overexpression lines suggest potential regulatory roles of OsPP2C10 in protein vesicle trafficking. Protein phosphatase 2Cs (PP2Cs) are key regulators of signal transduction that act through dephosphorylation of target proteins. To identify PP2Cs functioning on membranous organelles in rice (Oryza sativa), we screened all 78 OsPP2Cs and found that OsPP2C10 possesses a functional N-terminal transmembrane domain and is localized at the endoplasmic reticulum exit site. OsPP2C10 interacts with OsSAR1C, a component of the COPII complex, and OsPHYTOLONGIN, a VAMP72 longin-related protein, both of which are essential regulators of vesicle trafficking. Functional analysis using T-DNA knockout, RNAi knockdown, and overexpression lines revealed that OsPP2C10 influences the accumulation of secretory proteins such as TLP/PR5 and GLU2/PR2 in the apoplast. These findings suggest potential regulatory roles of OsPP2C10 in protein trafficking in rice.

Main conclusion: Enormous progress has been achieved in developing reliable in vitro propagation systems, microrhizome induction, genetic fidelity assessment, and conservation strategies in ginger. These advances, combined with modern molecular and genomic tools, ensure production of uniform, disease-free planting material and future genetic advancement in ginger. Ginger (Zingiber officinale Rosc.), a crop of immense culinary, medicinal, and industrial importance, has been the subject of extensive research in tissue culture and molecular improvement. In vitro regeneration systems, including shoot organogenesis, somatic embryogenesis, and microrhizome induction, have enabled the large-scale production of disease-free, uniform planting materials, addressing the limitations of conventional rhizome propagation. Complementary conservation strategies such as slow-growth storage, cryopreservation, and synthetic seed technology safeguard valuable germplasm, while molecular marker-based fidelity testing ensures true-to-type regeneration and enriches genetic diversity. Furthermore, biotechnological interventions such as genetic transformation, induced mutagenesis, and polyploidy induction expand the scope of crop improvement, offering opportunities for enhanced yield, stress resilience, and secondary metabolite production. Despite these advances, challenges remain in up scaling microrhizome-based propagation, optimizing transformation efficiency, and translating genomic insights into applied breeding. This review consolidates the advances in in vitro propagation, conservation, fidelity analysis, and molecular breeding of ginger, while highlighting the untapped potential of CRISPR-based genome editing. Collectively, these approaches present a roadmap for sustainable ginger improvement through the convergence of biotechnology, conservation, and molecular innovation.

Main conclusion: This study is a systematic review of heat stress-driven changes in tomato morphology and physiology, thermotolerance mechanisms, and crop improvement methods. Tomato is a widely cultivated and utilized crop. However, climate change poses a direct threat to food systems by diminishing the productivity and indirectly limiting the genetic diversity of crops and their wild relatives. Consequently, this limits future options for breeding improved varieties and makes it harder to adapt crops to new challenges. This is particularly concerning as the average global surface temperature is anticipated to increase by 0.3 °C over the next 10 years. Because of their sessile nature, tomato plants have developed complex signalling networks that allow them to detect changes in ambient temperature. However, high-temperature stress can negatively impact the morphology, physiology, and biochemistry of tomato plants at every stage of development, from vegetative to reproductive. This heat stress leads to significant yield losses due to induced changes in crop phenology, growth patterns, sensitivity to pests, shrinkage of the maturity period, and accelerated senescence. Finding novel sources of heat tolerance and identifying the genes involved in those pathways have become significant challenges in the modern era due to global warming. This complexity is further increased by significant genotype-environment and epistatic interactions, making it difficult for breeders to develop and select heat-tolerant genotypes. The current review aims to provide insights into physiological processes related to heat stress, the molecular underpinnings of tomato heat tolerance, germplasm and quantitative trait loci governing tolerance, and the different crop improvement techniques utilized in breeding for heat tolerance of tomato. Deciphering various physiological processes and the development of different breeding techniques are critical to assist in the evolution of thermotolerant tomato cultivars.

Main conclusion: Our work identified Ca²⁺-dependent and -independent changes in protein contents upon oxidative stress, showing that Ca²⁺ signaling shapes the early oxidative stress response and identifying potential targets for stress resilience research. Calcium (Ca²⁺) and reactive oxygen species (ROS) are key secondary messengers in plant stress signaling, yet their interplay in regulating proteome-wide responses remains poorly understood. We employed label-free quantitative (LFQ) proteomics to investigate Ca²⁺-dependent and -independent proteome changes in Arabidopsis thaliana leaves upon oxidative stress induced by hydrogen peroxide (H₂O₂). To dissect the role of Ca²⁺ signaling, we inhibited H₂O₂-induced Ca²⁺ transients by pre-treatment with the Ca²⁺ influx blocker LaCl₃. Throughout all four treatment samples - control, H₂O₂-treated, LaCl₃-treated, H₂O₂- and LaCl₃-treated - we identified a total of 3724 and 3757 proteins after 10 and 30 min, respectively. Of these, 581 proteins showed significant changes in abundance between the 10 min and 909 proteins between the 30 min sample groups. The combined LaCl₃ and H₂O₂ treatment resulted in the highest number of differentially abundant proteins (DAPs), indicating a strong attenuating effect of Ca²⁺ signaling on the oxidative stress response. By contrast, only 37 and 57 proteins responded to H₂O₂ alone with distinct subsets of strictly Ca²⁺-dependent, partially Ca²⁺-dependent, and Ca²⁺-independent proteins. Ca²⁺-independent H₂O₂-responsive proteins predominantly showed increased abundance, while strictly Ca²⁺-dependent proteins exhibited decreased abundance, suggesting a role for Ca²⁺ signaling in protein degradation. Furthermore, three proteins-WLIM1, CYP97C1, and AGAP1-underwent shifts in Ca²⁺-dependency between the two time points, pointing to a dynamic Ca²⁺-regulation. This study provides insight into short-term Ca²⁺-dependent and independent regulation of the Arabidopsis leaf proteome in response to oxidative stress, thereby identifying potential new targets for research on plant stress resilience mechanisms.