ABSTRACT In natural environments, plants are exposed to several abiotic stresses. Although plant responses to individual stressors have been well characterized, our knowledge of their responses to combined stressors is limited. In this study, we have analyzed the transcriptional responses of Arabidopsis to a combination of high light and cold stresses, because these conditions are considered major stressors that impact the same target, photosynthesis. Transcriptome analysis revealed that cold-activated genes can be divided into the following two groups: (1) genes whose expression is enhanced by high light and (2) genes whose expression is not enhanced by high light. The first group includes photoprotection-related genes, such as ELIP2 and CHS, and the second group includes DREB1A/CBF3-activated frost tolerance genes, which are associated with their physiological roles. Our findings help to elucidate the molecular machinery involved in plant acclimation during the winter season.

ABSTRACT Flood-induced hypoxia (low oxygen concentration) is increasing in frequency and intensity due to climate change, leading to significant crop yield losses and posing a major threat to global food security. S-nitrosoglutathione reductase (GSNOR) is a highly conserved, cysteine-rich homodimer that regulates the cellular level of the most abundant nitric oxide (NO) reservoir S-nitrosoglutathione (GSNO). GSNOR plays a fundamental role in NO homeostasis, as well as in plant development and stress responses, particularly hypoxia. This review summarizes the critical position of GSNOR in the plant hypoxia regulation network. We discuss how GSNOR controls the intracellular pool of S-nitrosothiols (SNOs), especially GSNO, thereby mitigating cytotoxic nitrosative stress while fine-tuning NO-mediated posttranslational modifications (PTMs), such as S-nitrosylation. Furthermore, we explored the regulation of GSNOR activity through various mechanisms, including oxidative PTMs and protein‒protein interactions. Targeted manipulation of GSNOR activity represents a promising strategy for enhancing flood tolerance in agriculturally important crops. We propose possible approaches for GSNOR manipulation and highlight urgent questions that must be addressed in future research to improve flood resilience in agricultural systems and protect global food security.

The use of biological control agents offers a sustainable alternative to chemical pesticides for managing soil-borne plant diseases. This study investigates the biocontrol potential of a newly isolated yeast strain, Meyerozyma guilliermondii INAT-MT731365, as a biotic elicitor to enhance growth and Fusarium crown and root rot (FCRR) resistance in hydroponically grown tomato plants. Tomato plants were treated with M. guilliermondii or left untreated as controls, then divided into two groups, one infected with Fusarium oxysporum f. sp. radicis-lycopersici (FORL) and one not infected. Physiological, biochemical, and molecular responses were monitored after treatment and inoculation. In the absence of the pathogen, M. guilliermondii treatment significantly enhanced plant growth and chlorophyll content. Concurrently, the yeast elicited a priming effect, characterized by low-level upregulation of PR1, β-1,3-glucanase and chitinase genes, downregulation of the P69G gene, and activation of defense enzymes such as peroxidase, chitinase, and β-1,3-glucanase, along with increased phenolic content and hydrogen peroxide accumulation, indicative of both SA- and JA/ET-mediated signalling induced systemic resistance (ISR). In control plants, FORL impaired plant defense with an early downregulation of β-1,3-glucanase and chitinase genes and stability in PR1 gene expression, followed by transient activation of peroxidase and chitinase and low activation of catalase, β-1,3-glucanase, and accumulation of phenolics. Upon FORL infection, treated plants exhibited strong upregulation of PR1, chitinase and β-1,3-glucanase genes mirrored by sustained increases in H₂O₂ and phenolic content and peroxidase, catalase, chitinase and β-1,3-glucanase activity. The simultaneous activation of both SA- and JA/ET-mediated signalling ISR resulted in a 61.8% reduction in FCRR severity and improved growth and photosynthetic traits. These findings highlight M. guilliermondii as a promising biocontrol agent that primes tomato plants for faster, stronger responses to soilborne pathogens while promoting growth under both healthy and stress conditions.

ABSTRACT Salinity stress severely limits soybean (Glycine max L.) productivity by disrupting physiological and biochemical processes. This study investigated the potential of magnesium oxide nanoparticles (MgO-NPs) to mitigate salt-induced damage. Soybean plants were grown under two salinity levels-non-saline (0 mM NaCl) and saline (75 mM NaCl)- in a controlled pot experiment. At the trifoliate stage, leaves were sprayed with MgO-NPs at 0, 100, 200, 400, and 600 ppm. Salinity markedly reduced relative water content (RWC) (to 69%), photosynthetic rate (to 20 µmol CO₂ m–2 s–1), and membrane stability index (MSI) (to 56%), while increasing oxidative stress markers. Foliar application of 400 ppm MgO-NPs significantly alleviated these effects, increasing RWC to 87%, photosynthesis to 35 µmol CO₂ m–2 s–1, and MSI to 78%. Treated plants showed higher chlorophyll and carotenoid contents, along with elevated proline and soluble sugars and reduced malondialdehyde (MDA) and hydrogen peroxide (H₂O₂) levels. Antioxidant activity improved modestly under both saline and non-saline conditions. Importantly, 400 ppm MgO-NPs enhanced yield traits under salinity, increasing pod number, 100-seed weight, and seed yield per plant by about 30%–38%. These results indicate that MgO-NPs, particularly at 400 ppm, effectively mitigate salinity stress by modulating physiological and biochemical mechanisms, with strong potential for improving soybean performance under saline environments. Field studies are suggested to validate practical application.

Drought stress is a major environmental factor limiting crop productivity worldwide. Plants respond to drought through various physiological mechanisms, including stomatal closure mediated by abscisic acid (ABA). This study investigated the relationship between leaf ABA content and stomatal closure in drought-tolerant cowpea (Vigna unguiculata) and drought-sensitive soybean (Glycine max). Under drought conditions, stomatal conductance decreased faster in cowpea than in soybean, significantly by day 2. Leaf ABA content increased earlier in cowpea, suggesting a strong correlation between ABA accumulation and stomatal closure. In contrast, both stomatal conductance and ABA accumulation were delayed in soybean. A lower ABA concentration was required to induce stomatal closure than in soybean, indicating that stomatal sensitivity to ABA was higher in cowpea. These findings suggest that cowpea’s superior drought tolerance is due to its rapid and more sensitive ABA-mediated stomatal response and provide insights for improving drought resilience in soybean through targeted breeding or biotechnological approaches.

ABSTRACT Silicon (Si4+) and selenium selenite (Se4+) exhibit antagonistic effects on cadmium (Cd2+). While plant electrophysiological sensors can quantify intracellular water and nutrient metabolism, the dynamic interactions between silicon and selenium in rice under cadmium stress remain unclear. This study focused on a rice variety (Yixiangyou 876, Enshi, Hubei Province, China), examining growth, photosynthesis, Se and Cd transport, and intracellular water and nutrient metabolism under varying silicon concentrations. Compared to Cd stress alone, the application of MSi (10 mM Si4+ and 8 μM Se4+) increased rice growth, significantly increasing water transfer rate (WTR), nutrient active translocation capacity (NAC), and nutrient transfer rate (NTR) by 148.57%, 192.01%, and 148.57%, respectively. This synergistic treatment promoted Se translocation and decreased Cd concentration. In contrast, HSi (15 mM Si4+ and 8 μM Se4+) suppressed rice growth, decreasing intracellular water holding capacity (IWHC) and NAC by 33.21% and 46.52%, respectively. Thus, 10 mM Si4+ in combination with Se4+ improved growth, photosynthesis, and intracellular water and nutrient transfer capacity in rice leaves and mitigated cadmium transport. This study provides scientific evidence for Enshi selenium-enriched cadmium-reduced rice. Its core value lies in converting complex physiological processes into quantifiable electrical signals, enabling researchers and farmers to precisely regulate the absorption and metabolism of selenium and cadmium in rice, ultimately achieving the agricultural goal of "high-quality, safe, and efficient" selenium-enriched agriculture.

ABSTRACT Urban greening had a significant effect on enhancing the distribution of alien plants, which pose a threat to the native species in new areas. Senecio angulatus L.f. (cape ivy) is one of the naturalized species dominant in urban ecosystems in many regions. This study was conducted to evaluate the allelopathic interference of this alien species on the native plants in these habitats in Iran. The allelopathy impact of aqueous extract of stem, leaf and root of cape ivy was estimated on germination and seedling´s growth of five native plants (Agropyron elongatum, Medicago sativa, Portulaca oleracea, Silybum marianum, and Lactuca sativa as indicator plant). The tested species differed in their susceptibility to allelopathy of cape ivy, in which M. sativa, P. oleracea, and L. sativa were significantly sensitive than other species. The inhibitory effect of aqueous extracts from leaves and stems was stronger than those from belowground parts and it revealed that the presence of higher concentrations of natural substances (phenols, flavonoids and antioxidant activity) gave it its efficiency in inhibiting the early growth of native plant. Our results imply that reducing the allelopathic impact of this species during habitat restoration requires the removal of the aboveground parts, including fallen leaves. Furthermore, the information obtained helps score cape ivy risk and impact assessment in the introduced regions.

ABSTRACT Volatile organic compounds (VOCs) are key determinants of the aroma characteristics in vegetable crops. They not only directly affect consumer sensory experiences but also play important roles in plant – environment interactions. With the continuous advancement of analytical technologies, the composition, biosynthetic pathways, and regulatory mechanisms of VOCs in vegetables have become research hotspots in recent years. This review systematically summarizes the major types of VOCs (aldehydes, esters, terpenes, and sulfur-containing compounds) in vegetable crops and the types of aromas they present. It further explores their biosynthetic pathways, such as those with fatty acids, amino acids, and carotenoids as precursors, as well as the synthesis pathways of terpenoids and phenylpropanoids. In addition, this review covers commonly used enrichment and analytical techniques, including HS-SPME, GC-MS, GC×GC-TOF-MS, as well as the various factors that influence VOC composition – such as genotype, developmental stage, environmental conditions, and postharvest handling. This work provides theoretical support and research directions for the breeding and industrial application of vegetable varieties with improved flavor quality. Future studies should further investigate the functions of VOCs, their regulatory networks, and their roles in plant ecological adaptation.

ABSTRACT WRKY transcription factors are important regulators of plant responses to environmental stresses and hormone signaling. This study analyzes the WRKY gene family in Solanum tuberosum by examining the phylogenetic relationships, expression profiles, and their roles in abiotic stress and hormone responses. Phylogenetic tree was constructed using 322 WRKY genes from four Solanum species: S. tuberosum, S. pennellii, S. pimpinellifolium, and S. lycopersicum. The results revealed conserved and expanded WRKY genes across these species. We then studied the expression of 75 SotuWRKY genes in response to salt, drought, heat stresses, and hormone treatments (IAA, ABA, BABA, GA3, and BAP). Results showed that 19, 25, and 29 genes were regulated under salt, drought, and heat stresses, respectively. Several WRKY genes (e.g. SotuWRKY03 and SotuWRKY24) were also regulated by biotic stresses like Phytophthora infestans infection and hormone treatments, indicating their involvement in plant defense mechanisms. A gene co-expression network was constructed based on gene-to-gene correlations, where SotuWRKY52 was identified as a hub gene, positively regulating six WRKY genes and negatively regulating four. These findings suggest that potato WRKY genes play key roles in regulating stress responses and hormone signaling, potentially enhancing potato resistance to stresses and diseases. This study provides new insights into WRKY transcription factors in S. tuberosum and other Solanum species.

ABSTRACT Chenopodium ficifolium is a close diploid relative of the tetraploid crop Chenopodium quinoa. Owing to its reproducible germination and seedling development, it becomes a promising model for studying floral induction, providing a basis for the comparison with C. quinoa. Two C. ficifolium genotypes differ in photoperiodic requirement: C. ficifolium 283 accelerates flowering under long days, whereas C. ficifolium 459 flowers earlier under short days. This study conducted a comprehensive transcriptomic and hormonomic analysis of floral induction in the long-day C. ficifolium 283 and compared the findings to previous experiments with the short-day C. ficifolium. Phytohormone concentrations and gene expression profiles during floral induction were largely similar between the two genotypes. However, a subset of genes exhibited contrasting expression patterns, aligning with the genotypes’ differing photoperiodic requirements. These genes, predominantly homologs of flowering-related genes in Arabidopsis thaliana, were activated under long days in C. ficifolium 283 and under short days in C. ficifolium 459. Notably, the contrasting expression of the FLOWERING LOCUS T-LIKE 2–1 gene, which was previously shown to induce precocious flowering in A. thaliana, confirmed its role as a floral activator, despite its low expression levels.