Search Results (2,557)

Post-translational modifications (PTMs) of proteins are involved in numerous biological processes, including signal transduction, cell cycle regulation, growth and development, and stress responses. WRKY transcription factors (TFs) play significant roles in plant growth, development, and responses to both biotic and abiotic stresses, making them one of the largest and most vital TF families in plants. Recent studies have increasingly highlighted the importance of PTMs of WRKY TFs in various life processes. This review focuses on the recent advancements in understanding the phosphorylation and ubiquitination of WRKY TFs, particularly their roles in resistance to biotic and abiotic stresses and in plant growth and development. Future research directions and prospects in this field are also discussed. Full article

Polyphenol oxidase (PPO) is a common metalloproteinase in plants with important roles in plant responses to abiotic and biotic stresses. There is evidence that PPOs contribute to stress responses in Paulownia fortunei. In this study, PPO gene family members in P. fortunei were comprehensively identified and characterized using bioinformatics methods as well as analyses of phylogenetic relationships, gene and protein structure, codon usage bias, and gene expression in response to stress. The genome contained 10 PPO gene family members encoding 406–593 amino acids, with a G/C bias. Most were localized in chloroplasts. The motif structure was conserved among family members, and α-helices and random coils were the dominant elements in the secondary structure. The promoters contained many cis-acting elements, such as auxin, gibberellin, salicylic acid, abscisic acid, and photoresponsive elements. The formation of genes in this family was linked to evolutionary events, such as fragment replication. Real-time quantitative PCR results showed that PfPPO7, PfPPO10, PfPPO1, PfPPO2, PfPPO3, PfPPO4, PfPPO5, and PfPPO8 may be key genes in drought stress resistance. PfPPO1, PfPPO3, PfPPO4, and PfPPO10 were resistant stress-sensitive genes. These results provide a reliable basis for fully understanding the potential functions of these genes and the selection of resistance breeding. Full article

Roses, a popular ornamental crop, often face various abiotic stresses during growth and development, such as cold, drought, and salinity. Rosa multiflora is a commonly used rootstock and exhibits strong resistance to both biotic and abiotic stresses, making it an ideal material for studying mechanisms for resistance. Among the largest plant families, MYB transcription factors play a crucial role in plant abiotic stresses. Our previous research has indicated that RmMYB44 could be involved in the low-temperature response of R. multiflora. This study further investigated RmMYB44, revealing that its expression levels were upregulated in response to chilling, drought, and salt stress. The results suggested its potential role as a key transcription factor in plant resistance to abiotic stresses. Additionally, RmMYB44 encoded a nuclear-localized protein without the self-activating function. The overexpression of RmMYB44 in tobacco plants enhanced the resistance to cold, drought, and salt stresses, as evidenced by the improved growth compared to wild-type (WT) plants under conditions of 4 °C, 30% water-holding capacity, and 200 mM of NaCl, respectively. Moreover, in overexpression tobacco plants, the levels of hydrogen peroxide and malondialdehyde (MDA) were significantly reduced; and the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT); as well as the proline content and the expression levels of NtPOD, NtCAT, and NtCBF; were significantly elevated under abiotic stresses. We assumed that the resistance to abiotic stress in plants conferred by RmMYB44 was associated with the regulation of cell membrane integrity. This study aimed to elucidate the role of the RmMYB44 gene in the resistance mechanism of R. multiflora against abiotic stress, thereby providing a candidate gene for the molecular breeding of abiotic stress resistance in roses and related species. Full article

Urban air pollution is a crucial global challenge, mainly originating from urbanization and industrial activities, which are continuously increasing. Vegetation serves as a natural air filter for air pollution, but adverse effects on plant health, photosynthesis, and metabolism can occur. Recent omics technologies have revolutionized the study of molecular plant responses to air pollution, overcoming previous limitations. This review synthesizes the latest advancements in molecular plant responses to major air pollutants, emphasizing ozone (O₃), nitrogen oxides (NO_X), and particulate matter (PM) research. These pollutants induce stress responses common to other abiotic and biotic stresses, including the activation of reactive oxygen species (ROSs)-scavenging enzymes and hormone signaling pathways. New evidence has shown the central role of antioxidant phenolic compound biosynthesis, via the phenylpropanoid pathway, in air pollution stress responses. Transcription factors like WRKY, AP2/ERF, and MYB, which connect hormone signaling to antioxidant biosynthesis, were also affected. To date, research has predominantly focused on laboratory studies analyzing individual pollutants. This review highlights the need for comprehensive field studies and the identification of molecular tolerance traits, which are crucial for the identification of tolerant plant species, aimed at the development of sustainable nature-based solutions (NBSs) to mitigate urban air pollution. Full article

Climate change presents numerous challenges for agriculture, including frequent events of plant abiotic stresses such as elevated temperatures that lead to heat stress (HS). As the primary driving factor of climate change, HS threatens global food security and biodiversity. In recent years, HS events have negatively impacted plant physiology, reducing plant’s ability to maintain disease resistance and resulting in lower crop yields. Plants must adapt their priorities toward defense mechanisms to tolerate stress in challenging environments. Furthermore, selective breeding and long-term domestication for higher yields have made crop varieties vulnerable to multiple stressors, making them more susceptible to frequent HS events. Studies on climate change predict that concurrent HS and biotic stresses will become more frequent and severe in the future, potentially occurring simultaneously or sequentially. While most studies have focused on singular stress effects on plant systems to examine how plants respond to specific stresses, the simultaneous occurrence of HS and biotic stresses pose a growing threat to agricultural productivity. Few studies have explored the interactions between HS and plant–biotic interactions. Here, we aim to shed light on the physiological and molecular effects of HS and biotic factor interactions (bacteria, fungi, oomycetes, nematodes, insect pests, pollinators, weedy species, and parasitic plants), as well as their combined impact on crop growth and yields. We also examine recent advances in designing and developing various strategies to address multi-stress scenarios related to HS and biotic factors. Full article

In the context of climate change, methods to improve the resistance of coniferous trees to biotic and abiotic stress are in great demand. The common plant response to exposure to vastly different stressors is the generation of reactive oxygen species (ROS) followed by activation of the defensive antioxidant system. We aimed to evaluate whether seed treatment with physical stressors can activate the activity of antioxidant enzymes and radical scavenging activity in young Picea abies (L.) H. Karst seedlings. For this, we applied seed treatment with cold plasma (CP) and electromagnetic field (EMF) and compared the response in ten different half-sib families of Norway spruce. The impact of the treatments with CP (1 min—CP1; 2 min—CP2) and EMF (2 min) on one-year-old and two-year-old P. abies seedlings was determined by the emergence rate, parameters of growth, and spectrophotometric assessment of antioxidant capacity (enzyme activity; DPPH and ABTS scavenging) in needles. The results indicated that the impact of seed treatment is strongly dependent on the genetic family. In the 577 half-sib family, the activity of antioxidant enzymes catalase (CAT), ascorbate peroxidase (APX), peroxidase (POX), and glutathione reductase (GR) increased after EMF-treatment in one-year-old seedlings, while similar effects in 477 half-sib family were induced by CP2 treatment. In two-year-old seedlings, CP1-treatment increased CAT, APX, POX, GR, SOD, DPPH, and ABTS activity in the 457 half-sib family. However, no significant impact of the treatment with CP1 was determined in one-year-old seedlings in this family. The application of novel technologies and the consideration of the combinatory impact of genetic and physical factors could have the potential to improve the accumulation of compounds that play an essential role in the defense mechanisms of P. abies. Nevertheless, for different resistance and responses to stressors of plants, their genetic properties play an essential role. A comprehensive analysis of interactions among the stress factors (CP and EMF), genetic properties, and changes induced in the antioxidant system can be of importance both for the practical application of seed treatment in forestry and for understanding fundamental adaptation mechanisms in conifers. Full article

N⁶-methyladenosine (m⁶A) RNA modification is the most prevalent form of RNA methylation and plays a crucial role in plant development. However, our understanding of m⁶A modification in Masson pine (Pinus massoniana Lamb.) remains limited. In this study, a complete analysis of m⁶A writers, erasers, and readers in Masson pine was performed, and 22 m⁶A regulatory genes were identified in total, including 7 m⁶A writers, 7 m⁶A erases, and 8 readers. Phylogenetic analysis revealed that all m⁶A regulators involved in Masson pine could be classified into three distinct groups based on their domains and motifs. The tissue expression analysis revealed that the m⁶A regulatory gene may exert a significant influence on the development of reproductive organs and leaves in Masson pine. Moreover, the results from stress and hormone expression analysis indicated that the m⁶A regulatory gene in Masson pine might be involved in drought stress response, ABA-signaling-pathway activation, as well as resistance to Monochamus alternatus. This study provided valuable and anticipated insights into the regulatory genes of m⁶A modification and their potential epigenetic regulatory mechanisms in Masson pine. Full article

Circular RNA (circRNA) is a type of non-coding RNA with multiple biological functions. Whole circRNA genomes in plants have been identified, and circRNAs have been demonstrated to be widely present and highly expressed in various plant tissues and organs. CircRNAs are highly stable and conserved in plants, and exhibit tissue specificity and developmental stage specificity. CircRNAs often interact with other biomolecules, such as miRNAs and proteins, thereby regulating gene expression, interfering with gene function, and affecting plant growth and development or response to environmental stress. CircRNAs are less studied in plants than in animals, and their regulatory mechanisms of biogenesis and molecular functions are not fully understood. A variety of circRNAs in plants are involved in regulating growth and development and responding to environmental stress. This review focuses on the biogenesis and regulatory mechanisms of circRNAs, as well as their biological functions during growth, development, and stress responses in plants, including a discussion of plant circRNA research prospects. Understanding the generation and regulatory mechanisms of circRNAs is a challenging but important topic in the field of circRNAs in plants, as it can provide insights into plant life activities and their response mechanisms to biotic or abiotic stresses as well as new strategies for plant molecular breeding and pest control. Full article

Tomatoes are one of the predominant vegetable crops grown throughout the year in Tamil Nadu, India. Their perishable nature and resource-intensive cultivation make them susceptible to biotic stress. The damage caused by invasive insect pests, bacterial wilt during the rainy season, and viral diseases are major yield-limiting factors, and the farmers mostly depend on calendar-based insecticide applications for insect pest and disease management in tomatoes. The desired tomato hybrids grafted onto bacterial wilt-resistant eggplant rootstocks offer protection against bacterial wilt during the rainy season. The integrated pest and disease management (IPDM) practices consist of resistant grafted tomato seedlings (wild eggplant rootstocks EG 203 and TS 03), bioinoculants (Bacillus subtilis + Trichoderma asperellum + Purpureocillium lilacinum), pheromone traps (Phthorimaea absoluta and Helicoverpa armigera), botanicals (azadirachtin), microbial pesticides (Bacillus thuringiensis, Metarhizium anisopliae, and Beauveria bassiana), and bio-rationals, which were evaluated in four locations in two major tomato-growing tracts of Tamil Nadu. The results revealed that the treatment EG 203 eggplant rootstock-grafted tomato along with IPDM practices performed better across all experimental locations than the other treatment combinations viz., TS 03 eggplant rootstock-grafted tomato + IPDM, tomato + IPDM, grafted tomato + farmers’ practice and tomato + farmers’ practice. The EG 203-grafted tomato recorded a higher yield than the farmers’ practice with significantly superior biometric parameters. The treatment of EG 203-grafted tomato and IPDM practices can be adopted for safer tomato production by enabling a reduction in pesticide applications while enhancing productivity. Full article

This study aims to evaluate the biocontrol potential of Meyerozyma guilliermondii (CECT13190), an endophytic yeast, and its role in mitigating the adverse effects of abiotic and biotic stress in cucumber plants. The relevance of this study lies in addressing the threat of Fusarium wilt, a major fungal disease that impacts cucumber crop productivity, as well as the exacerbation of food scarcity caused by climate change-induced abiotic stress factors such as high temperatures and drought. The study was conducted in a greenhouse environment where Cucumis sativus seedlings were exposed to biotic (F. oxysporum inoculation) and abiotic stress conditions (heat and water deficit). The impact of M. guilliermondii on treated plants’ physiology, growth, development, and flowering was assessed. The study confirmed the biocontrol activity of M. guilliermondii against F. oxysporum and highlighted its positive effects as a plant growth promoter. It enhanced overall plant health, activated natural defense mechanisms against F. oxysporum, and alleviated the detrimental impacts of abiotic stress. Notably, M. guilliermondii also induced early flowering in cucumber plants. This research underscores the potential of M. guilliermondii as a biocontrol agent for managing Fusarium wilt, enhancing stress tolerance, promoting early flowering, and offering promising prospects for sustainable crop production amidst fungal diseases and climate change-induced stressors. The findings emphasize the importance of utilizing M. guilliermondii to improve cucumber crop productivity and address food scarcity challenges. Full article

Factors such as extreme temperatures, light radiation, and nutritional condition influence the physiological, biochemical, and molecular processes associated with fruit development and its quality. Besides abiotic stresses, biotic constraints can also affect fruit growth and quality. Moreover, there can be interactions between stressful conditions. However, it is challenging to predict and generalize the risks of climate change scenarios on seasonal patterns of growth, development, yield, and quality of fruit species because their responses are often highly complex and involve changes at multiple levels. Advancements in genetic editing technologies hold great potential for the agricultural sector, particularly in enhancing fruit crop traits. These improvements can be tailored to meet consumer preferences, which is crucial for commercial success. Canopy management and innovative training systems are also key factors that contribute to maximizing yield efficiency and improving fruit quality, which are essential for the competitiveness of orchards. Moreover, the creation of habitats that support pollinators is a critical aspect of sustainable agriculture, as they play a significant role in the production of many crops, including fruits. Incorporating these strategies allows fruit growers to adapt to changing climate conditions, which is increasingly important for the stability of food production. By investing in these areas, fruit growers can stay ahead of challenges and opportunities in the industry, ultimately leading to increased success and profitability. In this review, we aim to provide an updated overview of the current knowledge on this important topic. We also provide recommendations for future research. Full article

The impacts of climate change are reaching unprecedented levels, heightening the risk of species loss and ecosystem service degradation. Wetlands, highly threatened ecosystems, serve vital ecological functions by capturing carbon, filtering water, and harbouring diverse wildlife. Coastal wetlands encounter many challenges, such as increased drought periods and escalating salinity levels, severely impacting plant biodiversity. Assessing how plants respond to various environmental stress factors is imperative for devising successful conservation strategies. In the present study, we examined three representative grass species found in various habitats within the Albufera Natural Park, close to the city of Valencia on the Spanish Mediterranean coast: Imperata cylindrica, Phragmites australis, and Saccharum ravennae. High salinity and water stress conditions were induced by subjecting the plants to irrigation with solutions containing 200, 400, 600, and 800 mM NaCl or withholding irrigation altogether to mimic coastal flooding and drought scenarios. The treatments were maintained until noticeable wilting of the plants occurred, at which point a range of stress biomarkers were determined, including photosynthetic pigments, ions, osmolytes, oxidative stress markers, and antioxidant metabolites, as well as antioxidant enzyme activities. Saccharum ravennae displayed the highest sensitivity to salt stress, whereas I. cylindrica appeared to be the most tolerant. The primary salinity tolerance mechanism observed in I. cylindrica and P. australis was a blockage of ion transport from the root zone to the aerial part, together with the salt-induced accumulation of proline and soluble sugars to high concentrations in the former. No significant effects of the water deficit treatment on the growth or biochemical parameters were observed for any of the analysed species. These findings offer valuable information for the effective management and conservation of coastal wetlands facing the challenges posed by climate change. Full article

Cytokinin (CK) is an important hormone that regulates cell differentiation. The CK content in plants is regulated by cytokinin oxidase (CKX), an important enzyme that participates in hormone-regulated pathways. Additionally, CKXs comprise a large family of enzymes, but little information exists on the CKXs in potato (Solanum tuberosum). In this study, nine CKXs were identified in the potato genome and named StCKX01-09, according to their order on the linkage groups (LGs). They belong to six subfamilies, and the members within the respective subfamilies had similar motifs, a similar gene structure, and similar cis-acting elements. Additionally, the CKXs from four other species, including Arabidopsis, rice (Oryza sativa), soybean (Glycine max), and maize (Zea mays), were also divided into six subfamilies, while members within each subfamily had similar types of motifs. Moreover, the potato StCKXs were shown to influence plant hormones and stress-related factors. StCKXs were collinear, with one CKX in Arabidopsis and five CKXs in Glycine max. Quantitative real-time PCR (qRT-PCR) revealed tissue-specific expression patterns in the potato seedlings and changes in the expression levels in response to stress. Furthermore, the cytokinin content and CKX enzyme activity were shown to be regulated by StCKXs. This study provides detailed information that can help future endeavors in the molecular breeding of potato (Solanum tuberosum). Full article

The use of endophytic microbes is increasing in commercial agriculture. This review will begin with a strain selection. Most strains will not function well, so only a few provide adequate performance. It will also describe the endophyte–plant relationship and the fungi and bacteria involved. Their abilities to alleviate biotic (diseases and pests) and abiotic stresses (drought, salt, and flooding) to remediate pollution and increase photosynthetic capabilities will be described. Their mechanisms of action will be elucidated. These frequently result in increased plant yields. Finally, methods and practices for formulation and commercial use will be described. Full article