Search Results (1,730)

Unsymmetrical dimethylhydrazine (1,1-Dimethylhydrazine, UDMH) is widely used as a high-performance liquid rocket propellant for the space industry globally. The release and leakage of UDMH into the environment, especially the soil environment, pose serious threats to ecosystems and human beings. In order to reveal the hazards of UDMH to soil and facilitate subsequent remediation, the adsorption behavior of UDMH in typical soil (yellow-brown soil, red soil, and black soil) matrices was explored, the environmental fate and toxicity of UDMH were presented by simulation calculation, and the phytotoxicity was evaluated by germination assay in the present study. The results showed that the adsorption performance of red soil, yellow-brown soil, and black soil for UDMH increased sequentially by integrating the findings from kinetic and thermodynamic studies. A highly significant correlation between the physicochemical and adsorption parameters for various soil matrices indicated a considerable impact of soil physicochemical properties on the adsorption behavior of UDMH in soils. The environmental fate simulation calculation indicated that UDMH and its transformation products were prone to being dissolved in soil water and migrating; however, once these compounds were present in the surface layer of dry soil, severe ecological and environmental pollution would occur. Based on a thorough evaluation of the toxicity parameters, formaldehyde dimethylhydrazone has been identified as demonstrating the most pronounced environmental toxicity profile, thus warranting prioritized attention. The results of a germination assay demonstrated that more than 100 mg·kg⁻¹ of UDMH in the soil would lead to strong phytotoxicity to plants, and more than 200 mg·kg⁻¹ of UDMH would significantly affect the early germination of seeds. Hence, this research provided helpful insights and theoretical support for the environmental fate and remediation of UDMH. Full article

The win–win situation of dye degradation and nitrogen fixation in wastewater using non-thermal plasma (NTP) were investigated in this study. Specifically, the feasibility of utilizing plasma-treated dye-contaminated wastewater for seed germination and plant growth was explored. Crystal Violet (CV) and Rhodamine B (RhB) dyes were used as model pollutants, while Sorghum bicolor (great millet) seeds were used to assess germination rates and plant growth responses. In untreated wastewater containing CV and RhB, approximately 45% of seeds germinated after three days, but no significant stem or root growth was observed after 11 days. Plasma treatment significantly enhanced dye degradation, with efficiency improving as treatment time and input power increased. After 16 min of plasma treatment at 1.3 ± 0.2 W input power, about 99% degradation efficiency was achieved for both CV (0.0122 mM) and RhB (0.0104 mM). This degradation was primarily driven by reactive oxygen and nitrogen species (RONS) generated by plasma discharge. When sorghum seeds were germinated using plasma-treated wastewater, the germination rate increased to 65% after three days—20% higher than with untreated wastewater. Furthermore, after 11 days, the average stem length reached 9 cm, while the average root length extended to 7 cm. These findings highlight NTP as a promising and sustainable method for degrading textile industry pollutants while simultaneously enhancing crop productivity through the reuse of treated wastewater. Full article

Plasma-activated water (PAW) is an eco-friendly technology with potential to improve seed germination and nutritional quality in microgreens. This study investigated the effects of PAW on three cultivars of kangkong (Ipomoea aquatica Forssk.). PAW activated for 10 min (PAW10) significantly enhanced seed germination and vigor, with effects comparable to those of a 15-min treatment. PAW10 treatment not only improved the accumulation of bioactive compounds—including total phenolics, flavonoids, ascorbic acid, chlorophylls, and carotenoids—but also enhanced antioxidant activity. These improvements were accompanied by elevated hydrogen peroxide (H₂O₂) levels and increased enzymatic activities, specifically catalase (CAT), superoxide dismutase (SOD), and ascorbate peroxidase (APX). Principal component analysis revealed cultivar-specific responses to PAW10. The Senafore 20 (SF) cultivar showed the most pronounced increases in antioxidant and antiglycation activities, as well as key bioactive compounds. The Phai-ngern (PN) cultivar exhibited elevated SOD activity and fiber content, while the Senee 20 (SN) cultivar showed minimal changes. These findings suggest that PAW10 effectively promotes germination and antioxidant-related biochemical responses in kangkong microgreens, with varying responses depending on cultivar. This study highlights PAW treatment as a promising approach to improve microgreen production and antioxidant capacity, supporting sustainable agriculture. Full article

Low-temperature stress severely restricts cotton seed germination and seedling establishment, especially in early spring. Ascorbic acid (AsA) priming is a promising strategy to enhance stress tolerance, yet its mechanisms in cotton remain unclear. This study examined the effects of AsA priming on seed germination at 15 °C. Seeds were treated with 0, 25, 50, or 100 mg/L AsA for 3, 6, 12, or 24 h. Results showed that 50 mg/L AsA for 24 h significantly improved germination potential, rate, index, and promptness index (p < 0.05). Compared with water-primed seeds, AsA-primed seeds exhibited greater radicle length (+17.67%) and fresh weight (+136.26%) under chilling stress. This treatment markedly increased antioxidant enzyme activities, including POD (+196.74%), SOD (+43.81%), and CAT (+49.43%), while also promoting the accumulation of Ascorbate–Glutathione cycle-related enzymes and metabolites, thereby reinforcing the antioxidant defense system. Multidimensional statistical analyses further indicated that AsA enhanced root growth by stimulating antioxidant defenses while inducing a trade-off that slightly reduced fresh weight, suggesting a balance between growth and oxidative protection. Overall, AsA priming improves cotton seed cold tolerance by activating enzymatic and non-enzymatic antioxidant systems and mediating a growth–defense trade-off, underscoring its potential as an effective priming agent for early sowing under low-temperature stress. Full article

Dongxiang wild rice (DXWR, Oryza rufipogon Griff.), the northernmost known wild rice species, exhibits exceptional tolerance to combined low-temperature and anaerobic stress during seed germination, providing a unique model for understanding plant adaptation to complex environmental constraints. Here, we employed an integrated multi-omics approach combining genomic, transcriptomic, and metabolomic analyses to unravel the synergistic regulatory mechanisms underlying this tolerance. Genomic comparative analysis categorized DXWR genes into three evolutionary groups: 18,480 core genes, 15,880 accessory genes, and 6822 unique genes. Transcriptomic profiling identified 10,593 differentially expressed genes (DEGs) relative to the control, with combined stress triggering the most profound changes, specifically inducing the upregulation of 5573 genes and downregulation of 5809 genes. Functional characterization revealed that core genes, including DREB transcription factors, coordinate energy metabolism and antioxidant pathways; accessory genes, such as glycoside hydrolase GH18 family members, optimize energy supply via adaptive evolution; and unique genes, including specific UDP-glycosyltransferases (UDPGTs), confer specialized stress resilience. Widely targeted metabolomics identified 889 differentially accumulated metabolites (DAMs), highlighting significant accumulations of oligosaccharides (e.g., raffinose) to support glycolytic energy production and a marked increase in flavonoids (153 compounds identified, e.g., procyanidins) enhancing antioxidant defense. Hormonal signals, including jasmonic acid and auxin, were reconfigured to balance growth and defense responses. We propose a multi-level regulatory network based on a “core-unique-adaptive” genetic framework, centered on ERF family transcriptional hubs and coordinated through a metabolic adaptation strategy of “energy optimization, redox homeostasis, and growth inhibition relief”. These findings offer innovative strategies for improving rice stress tolerance, particularly for enhancing germination of direct-seeded rice under early spring low-temperature and anaerobic conditions, by utilizing key genes such as GH18s and UDPGTs, thereby providing crucial theoretical and technological support for addressing food security challenges under climate change. Full article

The growing interest in pitaya has led to an increase in its cultivation worldwide. Unfortunately, the production of pitaya often depends on expensive hand-pollination. In this experiment, we compared the efficiency of different procedures in transferring pollen grains to flower stigmas and analyzed pollen–pistil interactions, fruit set, and quality in response in ‘Royal Red’, a self-compatible genotype of pitaya. The results show that pollen adhesion on the stigma achieved by transferring pollen with a paintbrush or with a duster was higher than pollen adhesion using blowers and much higher than the pollen load in the stigmas of open-pollinated or bagged flowers. However, good pollen germination and sufficient pollen tube growth in the flowers pollinated using blowers enabled high fruit and seed sets, leading to the production of fruits of commercial size in a less expensive manner. The results of free open pollinated and bagged flowers matched exactly, highlighting that the occasional insect visitors of the freely exposed flowers in the greenhouses of southeast Spain are not efficient pollinators. The high fruit set obtained in bagged flowers confirms the self-compatibility of this genotype, although the reduced pollen load and low pollen germination led to smaller fruit with fewer seeds. Full article

Pre-harvest sprouting (PHS) reduces the quality and quantity of crop seeds. PHS can be imposed through the embryo or husk pathway of cereal crops. Most reported PHS seeds are imposed via the embryo pathway. Here, we generated transgenic rice plants overexpressing rice melatonin 2-hydroxylase (OsM2H), which catalyzes the hydroxylation of melatonin to 2-hydroxymelatonin (2-OHM). OsM2H overexpression (M2H-OE) showed PHS under paddy conditions. Germination assays revealed that intact seeds harvested at 26 and 36 days after heading (DAH) showed PHS, whereas dehusked seeds did not, indicating husk-imposed PHS. Overproduction of 2-OHM was observed in M2H-OE seeds compared to wild-type control. In addition, M2H-OE lines produced more hydrogen peroxide than the wild-type. 2-OHM-induced reactive oxygen species resulted in the induction of OsGA3ox2, a gibberellin (GA) biosynthesis gene, and repression of OsGA2ox3, a GA degradation gene, in caryopses at 2 DAH, but in the induction of the ABA degradation gene OsABA8ox3 in intact seeds at 26 DAH. In addition, M2H-OE seedlings were longer and showed increased levels of hydrogen peroxide and OsGA3ox2 expression versus the wild-type. This is the first report showing that 2-OHM can induce PHS via the husk pathway in rice seeds through the induction of GA biosynthetic and ABA degradation genes. Full article

This study presents the development and evaluation of an automated ultraviolet-C irradiation system for maize seed treatment, emphasizing disinfection performance, environmental control, and vision-based monitoring. The system features dual 8-watt ultraviolet-C lamps, sensors for temperature and humidity, and an air extraction unit to regulate the microclimate of the chamber. Without air extraction, radiation stabilized within one minute, with internal temperatures increasing by 5.1 °C and humidity decreasing by 13.26% over 10 min. When activated, the extractor reduced heat build-up by 1.4 °C, minimized humidity fluctuations (4.6%), and removed odors, although it also attenuated the intensity of ultraviolet-C by up to 19.59%. A 10 min ultraviolet-C treatment significantly reduced the fungal infestation in maize seeds by 23.5–26.25% under both extraction conditions. Thermal imaging confirmed localized heating on seed surfaces, which stressed the importance of temperature regulation during exposure. Notable color changes ($\Delta E>2.3$) in treated seeds suggested radiation-induced pigment degradation. Ultraviolet-C intensity mapping revealed spatial non-uniformity, with measurements limited to a central axis, indicating the need for comprehensive spatial analysis. The integrated computer vision system successfully detected seed contours and color changes under high-contrast conditions, but underperformed under low-light or uneven illumination. These limitations highlight the need for improved image processing and consistent lighting to ensure accurate monitoring. Overall, the chamber shows strong potential as a non-chemical seed disinfection tool. Future research will focus on improving radiation uniformity, assessing effects on germination and plant growth, and advancing system calibration, safety mechanisms, and remote control capabilities. Full article

Annually, about 2.4 million tons of superabsorbent polymers (SAPs) used in disposable diapers are thrown away, polluting our planet. This study aims to explore the potential for reusing SAPs removed from diapers to enhance soil water retention. To this end, the swelling and water retention properties of SAP gels from three different types of diapers were compared to those of an agricultural gel, Aquasorb. Sand was used as a model for soil. When mixed with sand, diaper gels have a swelling degree of ca. 100 g per gram of dried polymer, and a swelling pressure of 12–26 kPa, which are similar to those of Aquasorb gel. Using a synthesized poly(acrylamide-co-sodium acrylate) gel as an example, the correlation between the swelling pressure and the compression modulus of the swollen gel was demonstrated. Soil-hydrological constants were estimated from water retention curves obtained by equilibrium centrifugation of gel/sand mixtures. It was observed that adding 0.3 vol% of diaper gels to sand leads to a 3–4-fold increase in water range available to plants, which is close to that provided by agricultural gel Aquasorb. The water-holding properties were shown to be maintained during several swelling/deswelling cycles in the sand medium. The addition of diaper gels to soil had a significant positive impact on mustard (Brassica juncea L.) seed germination and seedling growth, similar to the agricultural gel Aquasorb. This suggests high potential for the reuse of SAPs from diaper waste to improve soil water retention and water accessibility to plants. This would provide both economic and environmental benefits, conserving energy and raw materials to produce new agricultural gels and limiting the amount of waste. Full article

Melon has great economic importance in Brazil, and flower development is the basis for fruit and seed production. The objective of this study was to elucidate the variability of flowering characteristics and to compare qualitative and quantitative reproductive variations in relation to pollen viability and stigmatic receptivity in 21 genotypes, which includes 15 Brazilian accessions. In addition, we evaluated the influence of time on the growth of the pollen tube and its arrival at the ovule in vivo at different intervals (1 h, 2 h, 3 h) after hand pollination in three commercial varieties, one exotic accession, and two intervarietal hybrids, by epifluorescence technique. Three groups were distributed by the clustering method of Scott–Knott at 5% probability; group III included only commercial varieties for the flower width descriptor. C. melo germplasm presented 81% andromonoecious plants and 19% trimonoecious plants. Through the multivariate strategy, these 21 genotypes were distributed into six groups with distinct reproductive characteristics, and male flowering was accelerated compared to female flowering. Regarding pollen viability, it was greater than 95% according to staining methods. Pollen germination rate in vivo was affected by time, with an almost 12.5% increase between 1 h and 3 h after hand pollination, and the in vivo pollen germination in hybrids was lower than in commercial varieties. Brazilian accessions, despite stability in pollen viability and stigma receptivity, have great differences in reproductive terms, such as variations in the quantitative and qualitative characteristics of floral pieces and flowering. This work contributes to the knowledge on varieties, hybrids, exotic accession, and Brazilian melon germplasm by characterizing some of their main agricultural traits, such as reproduction floral biology, and opens up prospects for yield evaluation in plant breeding programs. Full article

The germination, seedling growth, and crop productivity of maize seeds are significantly impacted by seed aging. This study investigated the efficacy of silver nanoparticles (AgNPs) as a seed priming agent for maize inbred lines exhibiting varying degrees of aging tolerance. Two inbred lines, aging-sensitive I178 and aging-tolerant X178, were used. AgNP treatment significantly promoted the germination of I178 (from 55% to 85%, compared with water treatment). Notable improvements were observed in root length, shoot length, and lateral root formation after AgNP treatment in I178. However, X178 showed no significant changes in germination and seedling growth after the AgNP treatment. Further transcriptomic analysis was performed on X178 and I178 before (water treatment) and after AgNP treatment to study genes and the expression network of the mechanism induced by AgNP promotion. In I178, AgNP treatment led to a substantial increase in differentially expressed genes (DEGs). A total of 800 DEGs were identified, with 517 being upregulated and 283 downregulated. The DEGs in I178 were mainly involved in metabolic processes, stress responses, and membrane repair. For example, genes related to lipid metabolism and membrane integrity were upregulated, along with seven genes associated with antioxidant action and redox metabolism. This indicates that AgNPs might enhance membrane stability and stress tolerance in I178. In contrast, X178 had a limited transcriptomic response to AgNP treatment. Although 874 DEGs were detected, the number of genes related to key processes like those in I178 did not change significantly, which is in line with its inherent aging tolerance. Overall, these results suggest that AgNPs can effectively improve seed vigor and counteract the negative effects of seed aging, especially in aging-sensitive maize lines. The mechanism likely occurs through regulating gene expression related to stress response, metabolic repair, and membrane stability. This study provides new insights into the molecular basis of AgNP-mediated seed vigor enhancement, which has potential implications for improving seed quality in agricultural production. Full article

As an important complementation of plant genetic traits, seed endophytes (SEs) have garnered significant attention due to their crucial roles in plant germination and early seedling establishment. In this study, we employed both culture-dependent and amplicon sequencing-based approaches to characterize the endophytic microbiome in seed samples derived from different individual Panax notoginseng plants. Additionally, we evaluated the antagonistic activity of isolated culturable bacterial SEs against the root rot pathogens Fusarium solani and F. oxysporum. Our results demonstrated that a greater sampling quantity substantially increased the species richness (Observed OTUs) and diversity of seed endophytic microbiota, underscoring the importance of seed population size in facilitating the vertical transmission of diverse endophytes to progeny. The endophytic communities (including both fungi and bacteria) exhibited a conserved core microbiota alongside host-specific rare taxa, forming a phylogenetically and functionally diverse endophytic resource pool. Core bacterial genera included Streptococcus, Methylobacterium-Methylorubrum, Sphingomonas, Burkholderia-Caballeronia-Paraburkholderia, Pantoea, Halomonas, Acinetobacter, Pseudomonas, Vibrio, and Luteibacter, while core fungal genera comprised Davidiella, Thermomyces, Botryotinia, Myrothecium, Haematonectria, and Chaetomium. Among 256 isolated endophytic bacterial strains, 11 exhibited strong inhibitory effects on the mycelial growth of F. solani and F. oxysporum. Further evaluation revealed that two antagonistic strains, Bacillus cereus and B. toyonensis, significantly enhanced seed germination and plant growth in P. notoginseng, and effectively suppressed root rot disease in seedlings. These findings highlight the potential use of SEs as biocontrol agents and growth promoters in sustainable agriculture. Full article

The Northeast region in China is a major maize-producing area; however, low-temperature stress (TS) limits maize (Zea mays L.) seed germination, affecting population establishment and yield. In order to systematically explore the regulation mechanism of maize radicle which is highly sensitive to low-temperature environment response to TS, seeds of ZD958 and DMY1 were used to investigate germination responses under 15 °C (control) and 5 °C (TS) conditions. Phenotypic, physiological, transcriptomic, and metabolomic analyses were conducted on the radicles after 48 h of TS treatment. TS caused reactive oxygen species (ROS) imbalance and oxidative damage in radicle cells, inhibiting growth and triggering antioxidant defenses. Integrated transcriptomic and metabolomic analyses revealed that flavonoid metabolism may play a pivotal role in radicle responses to TS. Compared with the control treatment, ZD958 and DMY1 under TS treatment significantly increased (p < 0.01) the total flavonoid content, total antioxidant capacity, 4-coumarate-CoA ligase activity, and dihydroflavonol 4-reductase activity by 15.99% and 16.01%, 18.41% and 18.54%, 63.54% and 31.16%, and 5.09% and 7.68%, respectively. Despite genotypic differences, both followed a shared regulatory logic of “low-temperature signal-driven—antioxidant redirection—functional synergy.” This enabled ROS scavenging, redox balance, and antioxidant barrier formation, ensuring basal metabolism and radicle development. Full article

The effects of different storage conditions on seed germination and mortality may exhibit species-specific patterns. Burial serves as a natural seed storage mechanism, and its impact on seed germination and mortality holds critical implications for understanding the formation mechanisms of soil seed banks and the restoration of vegetation. Seed size is closely related to storage conditions, as it affects the ease with which seeds penetrate the soil, thereby potentially influencing their germination and mortality responses to those storage conditions. This study used 12 common plant species from a subalpine wet meadow. Employing in situ unheated storage as the control and in situ burial at a 15 cm depth (for seven months) as the experimental treatment, we aimed to explore the effects of burial on seed germination and survival, as well as the underlying mechanisms, in relation to seed size. The results showed the following: (1) Compared with the control, the burial treatment significantly increased the germination rates of four species (burial-promoted germination type), while no significant effect was observed on the germination of the remaining eight species (burial-insensitive germination type); it significantly increased the mortality rate of two species (survival-inhibited type), significantly decreased the mortality rate of four species (survival-promoted type), and had no significant impact on the mortality rate of the remaining six species (survival-insensitive type). (2) Seed size exhibited significant negative correlations with both post-burial germination rates and mortality rates under control conditions, while showing a significant positive correlation with the magnitude of mortality change. The species-specific responses of seed germination and mortality to storage conditions, and their close association with seed size, represent products of long-term plant evolution. This study provides important insights for understanding the mechanisms of soil seed bank formation and offers valuable guidance for vegetation restoration practices. Full article

Sustainable development requires implementation of eco-friendly practices and a circular approach in both agricultural and industrial systems. This study evaluated winery flotation wastewater (WFW) as a cultivation substrate for Bacillus sp. 10/R isolated from grapevine rhizosphere for sustainable biostimulant production. The bacterial isolate was characterized by 16S rRNA sequencing and biochemical tests, showing the highest similarity with Bacillus mojavensis and Bacillus halotolerans. Plant growth-promoting traits were assessed via assays for hydrolytic enzymes, ACC (1-aminocyclopropane-1-carboxylate) deaminase, and IAA (indole acetic acid) production, as well as for phosphate solubilization. The isolate was cultivated in WFW, including monitoring of biomass growth, enzymatic activity, and substrate composition changes. The resulting cultivation broths based on WFW (WFW-CB) and nutrient broth (NB-CB) were tested as barley seed treatment at five dosages, using sterile media and water as controls. The results have displayed strong pectinase (EAI–enzyme activity index 2.79) and cellulase activity (2.33), moderate xylanase (1.75) and ACC deaminase activity (growth zone 54.67 ± 0.58 mm), and moderate IAA production (9.66 µg/mL). Biomass content has increased by two log units within 48 h (up to 9.06 log CFU/mL), with stable pectinase activity (~2.2 U/mL). Germination assays revealed that 10% WFW-CB and 50% WFW enhanced germination indices and biomass, whereas undiluted WFW and WFW-CB inhibited germination. These results indicate that WFW is a suitable substrate for Bacillus sp. 10/R cultivation, linking industrial wastewater valorization with plant biostimulant production in a circular economy framework. Full article