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Main conclusion: Virus-like particles (VLP) from hepatitis C virus were successfully produced in Nicotiana benthamiana plants for the first time, by co-expressing three viral proteins (Core, E1 and E2) in a polycistron-like arrangement. Hepatitis C virus (HCV) remains a global health challenge, underscoring the need for a preventive vaccine. Virus-like particles (VLP) offer a safe alternative, as they resemble native virions without infectious genomes. We expressed the HCV structural proteins Core, E1, and E2 in Nicotiana benthamiana using binary and deconstructed viral vector systems. Western blot confirmed expression, with the binary system achieving higher yields. Purified proteins assembled into spherical VLP (40-60 nm) were confirmed by electron microscopy. These findings demonstrate for the first time the feasibility of producing complete HCV-VLP in plants, supporting their potential as a scalable platform for vaccine development.

Main conclusion: This review highlights endophyte occurrence and diversity, mechanisms, signaling crosstalks, and innovative coating applications, positioning endophytes as eco-friendly tools bridging fundamental research and practical crop protection in horticultural crops. Endophytes are microorganisms that asymptomatically reside in plant tissues proving to be valuable partners in the realm of sustainable horticultural disease management. Their prevalence and diversity on horticultural crops indicate that there is a large pool of such microbial taxa with underused potential for promoting plant health. These endophytes use a variety of mechanisms in their fight against pathogens, including direct antagonism, niche and nutrient competition, and triggering of host defense mechanisms. Signaling crosstalk of the endophytes with the host plants can reprogram pathways like jasmonic acid, salicylic acid, and ethylene, leading to primed immunity and enhanced stress tolerance. The creation of enzymes (chitinase, glucanase) and bioactive metabolites is the main mechanism of pathogen growth suppression, while antimicrobial compounds and secondary metabolites are aimed at defense. Recent advances point out the promising use of endophytic formulations as bio-coatings on fruits to limit their post-harvest diseases, thus making the endophytic concept an eco-friendly substitute for synthetic chemicals. Advancements in the development and commercialization of endophyte-based coating materials demonstrate that they hold much promise as a low-cost and environmentally benign disease management strategy for horticultural industries.The aim of this review is to summarize recent insights into the diversity, molecular and biochemical mechanisms of action against pathogens, and translational potential of the metabolites from endophytes. It also calls attention to the endophytic coating as a new type of endophyte application that represents a bridge between basic research and an actual commercial coating. Taken collectively, this knowledge places endophytes as attractive parts of eco-sound, biologically initiated system of crop protection.

As a promising alternative source of natural rubber production, Taraxacum kok-saghyz Rodin (TKS) demonstrates significant rubber biosynthesis capacity in its root system. To elucidate the transcriptional regulation of rubber biosynthesis, we conducted a comprehensive genome-wide identification of transcription factors (TFs) and their temporal expression patterns during root development. Through genome-wide analysis, we identified 2095 transcription factors (TFs) distributed among 68 families in TKS; with the AP2/ERF-ERF family being the largest, comprising 169 members. RNA-seq profiling across developmental stages (10-80 DAP) revealed distinct spatiotemporal expression patterns. TF expression was initially elevated in young stems, while root-specific TFs, particularly from the WRKY family, peaked at 72 DAP. Sixteen root-enriched TF candidates were functionally validated for tissue specificity, with TkA01G586780 emerging as a key regulator showing elevated expression in mature taproots, transcriptional autoactivation capability in yeast, and activates promoter regions of three mevalonate pathway genes (ACAT3, HMGR6, MVK3) essential for rubber biosynthesis. This study provides the first systematic characterization of TKS transcription factors, revealing critical regulatory networks governing root development and rubber biosynthesis. Our findings establish valuable genomic resources for molecular breeding strategies to enhance rubber yield in this industrially significant alternative crop.

Main conclusion: This review summarizes manganese hyperaccumulators and plant mechanisms for tolerating excess Mn to advance phytoremediation. Manganese (Mn) is an essential micronutrient for plant growth and development, extensively involved in various physiological processes, but becomes phytotoxic when in excess. In recent years, amid rapid industrialization and urbanization, environmental Mn pollution has intensified, posing a significant threat to ecosystems and human health. Among various remediation technologies, phytoremediation has garnered significant attention for its environmental friendliness and cost-effectiveness. Globally, numerous Mn hyperaccumulators have been identified, including Phytolacca americana L., Celosia argentea L., and Persicaria perfoliata (L.) H. Gross. These plants not only thrive in high-Mn environments but also exhibit strong Mn accumulation and tolerance, making them ideal candidates for the remediation of Mn pollution. Compared to existing reviews, this review provides a systematic compilation of Mn hyperaccumulator resources reported in both domestic and international studies. It is the first to offer a comprehensive synthesis of multiple mechanisms underlying tolerance to Mn excess, encompassing compartmentalization, antioxidant effects, chelation, restriction of uptake and efflux, and plant-microbe interactions. Particular emphasis is placed on integrating and applying omics research in this field. This review aims to provide a theoretical reference for further elucidating the mechanisms of plant tolerance to excess Mn, exploring plant resources with high Mn tolerance, and promoting the practical application of phytoremediation technology.

Main conclusion: Salinity tolerance in rice is a multilevel trait integrating ion and ROS homeostasis, tissue tolerance, and whole-plant physiology; future breeding requires combining omics-guided selection, genome editing, and field-relevant phenotyping. Salinity stress is one of the extreme abiotic stress factors that reduces rice yield (Oryza sativa L.) and affects about 20% of the worldwide irrigated rice growing area. The present analysis describes the molecular and physiological aspects of salinity tolerance in rice with particular reference to ion homeostasis, osmotic adjustment, and oxidative stress. High-affinity potassium transporters (HKT) and sodium/hydrogen exchangers (NHX) are necessary ion transporters for ion homeostasis in the cell under salt conditions, as ions are abundant outside the cell. However, the rise in reactive oxygen species (ROS) levels and their damaging effects on cellular machinery are suppressed by rice's enzymatic and non-enzymatic antioxidant mechanisms. Producing osmoprotectants such as proline and glycine betaine also assists rice plants in overcoming turgor and protecting protein structures in conditions of osmotic stress. Recent biotechnological practices such as using CRISPR/Cas9 gene editing approaches, transcriptomic research, and epigenetic change-wise phenotypes have opened novel avenues to improve the tolerance of rice plants to soil salinity. At the same time, other challenges exist, such as the polygenic nature of the trait and significant genotype by environmental interactions, which pose serious issues. This review particularly calls for international efforts, through the sharing of knowledge and resources, aimed at developing salt-tolerant rice varieties to prevent food shortages in regions affected by the salinization of soils.

Main conclusion: Exposure of bryophytes to elevated CO₂ initially stimulated photosynthetic activity, but this benefit was rapidly lost in time. Desiccation tolerance did not improve in any of the four bryophyte species studied. The majority of studies have focused on the influence of rising CO₂ levels on vascular plants, while bryophytes have received less attention, despite being major contributors to biodiversity in high latitudes, to facilitate water regulation in ecosystems, and support carbon and nutrient cycling. Elevated CO₂ typically results in greater carbon availability for cell processes (reparation, osmotic regulation) and allows plants to achieve a greater internal CO₂ concentration at any level of plant water content. Thus, we hypothesized that growth under elevated CO₂ increases moss desiccation recovery. We conducted a one-year growth chamber experiment with four bryophyte species (Conocephalum salebrosum, Dicranum scoparium, Pleurozium schreberi, and Rhytidiadelphus squarrosus) to assess the effect of elevated CO₂ (1000 μmol CO₂ mol^-1) on bryophyte desiccation tolerance based on CO₂ assimilation, carbon balance and chlorophyll fluorescence measurements. Despite the initial CO₂ assimilation and carbon gain improvements, such benefits were generally rapidly lost. Enhancement of desiccation tolerance through improvement in assimilation recovery was observed for different species at different time points, while generally, these benefits did not preserve either. Especially sensitive to elevated CO₂ was the photosynthetic recovery at 24 h, where significant reduction of desiccation tolerance in D. scoparium and P. schreberi below the control levels was observed, indicating a potential decrease of the long-term performance. In summary, our results suggest that there is no clear long-term positive effect of increased CO₂ on bryophyte desiccation-rehydration stress tolerance for the species studied, adding a new layer of complexity to the effect of global change on bryophyte flora.

Main conclusion: Superhydrophobicity and self-cleaning (Lotus Effect) came only in focus of research after 1997. Botanic systematic studies led to a paradigm shift in materials science and numerous technical applications. However, physics behind it is still not fully understood. Details on the discovery, consequences, and open questions are presented. Extreme water repellency (superhydrophobicity) is a feature of many biological surfaces from terrestrial cyanobacteria to green plants and animals. The initially controversially discussed publication "Purity of sacred Lotus or escape from contamination on biological surfaces" (Planta 1997) showed that defined hierarchically structured superhydrophobic surfaces reduce the adhesion of pathogens and particles as defense mechanism. The technical applicability was indicated, and the publication initiated about 2000 publications annually and numerous applications in our daily life. Although cuticular plant surfaces are probably the largest homogenous interfaces on our planet, they came very late in the focus of research. Functional principles, occurrence of self-cleaning biological surfaces, the physical background, patenting consequences, and open questions are discussed.

Main conclusion: CRISPR/Cas9-mediated dual knockout of VviGAI1 and VviFLC in grapevine promotes early flowering and induces distinctive morphological changes, offering novel genetic resources for breeding. CRISPR/Cas9-mediated genome editing offers a transformative approach for grapevine improvement. In this study, we achieved simultaneous knockout of two central flowering regulators VviGAI1, a DELLA protein ortholog, and VviFLC, a floral repressor in Vitis vinifera 'Cabernet Sauvignon' using a dual-sgRNA vector system. Remarkably, all 15 independent edited lines exhibited biallelic mutations in both genes, primarily consisting of frameshifts that led to premature termination. The dual-mutant plants displayed a range of distinctive phenotypic alterations, including dwarfism, shortened internodes, modified leaf morphology, and disrupted tendril development. Notably, one line (EL-43) showed precocious flowering under greenhouse conditions, underscoring the synergistic role of VviGAI1 and VviFLC in repressing floral transition. Comparative analysis with previously reported gai mutants revealed both conserved and novel traits, suggesting that structural variation within the DELLA domain contributes to phenotypic diversity. Collectively, our findings establish that dual editing of VviGAI1 and VviFLC not only accelerates flowering but also introduces unique vegetative and reproductive characteristics, providing a valuable genetic resource for future grapevine domestication and precision breeding efforts.

Main conclusion: This study demonstrates the use of photothermal AFM-IR and vibrational SFG microscopy to investigate nanoscale chemical heterogeneity and mesoscale cellulose microfibril orientation in hybrid poplar xylem, revealing differences in cellulose microfibril (CMF) orientation between fiber and vessel cell walls that are consistent with their mechanical support and hydraulic functions. Understanding the structural organization of cellulose microfibrils (CMFs) within individual plant cell walls is essential for connecting cell wall architecture to its mechanical and physiological functions. However, due to the complex hierarchical structure and nanoscale heterogeneity of cell walls, it remains technically challenging to resolve detailed compositional and orientational information at subcellular levels of individual cell walls. This study investigates the internal 3D structure, chemical composition, and sublayer organization of fiber and vessel cell walls in the xylem tissue of a two-year-old field-grown hybrid poplar tree (Populus alba × P. glandulosa) using photothermal atomic force microscopy coupled with infrared spectroscopy (AFM-IR) and sum frequency generation (SFG) hyperspectral microscopy. AFM-IR provided nanoscale chemical imaging, revealing localized compositional heterogeneity, including variations between adjacent cell walls and transitional layers beyond the traditional S1, S2, and S3 sublayers. SFG microscopy revealed that CMFs in fiber walls are highly aligned along the stem axis, consistent with their role in mechanical support, while vessel cell walls exhibited slightly tilted CMFs, reflecting their function in hydraulic transport. Together, these results offer new insights into cell-type-specific CMF organization and compositional gradients in hybrid poplar xylem. These findings highlight the structural and chemical complexity of secondary cell walls in woody plants and demonstrate the value of AFM-IR and SFG spectroscopy in elucidating plant cell wall architecture.