Search Results (121)

Seed science is the comprehensive study of seeds. It encompasses their biology, production, technology, genetics, physiology, ecology, and applications in agriculture and conservation. Seed science has undergone transformative advancements through the integration of microbial technologies, with beneficial microorganisms emerging as critical tools for enhancing germination, seedling vigor, and crop resilience. Research demonstrates that microbial treatments improve nutrient uptake, hormonal regulation, and stress tolerance while establishing early symbiotic relationships with plants. This review synthesizes recent advances in understanding the roles of beneficial microbes in seed science, focusing on their impact on seed germination, seedling growth, and plant health. We explore the composition and transmission of seed microbiomes, highlighting the vertical transfer of microbes from parent plants to seeds and the influence of environmental factors on microbial community structure. The review also discusses innovative approaches to seed microbiome engineering. Particular attention is given to seed biopriming with plant growth-promoting bacteria (PGPB), which has shown significant potential in improving germination rates, seedling vigor, and crop productivity. Specific microbial strains, such as Trichoderma species and Pseudomonas fluorescens, are discussed with emphasis on their mechanisms of action in enhancing plant performance. The review also addresses the impact of breeding on seed microbiomes and explores emerging research directions, including the development of tailored microbial inoculants and the investigation of intracellular seed bacteria. By synthesizing these findings, this review aims to provide a comprehensive summary of the current state of seed microbiome research and its implications in seed science for sustainable agriculture. Full article

Forests face increasing threats due to climate change and anthropogenic pressures, exacerbating plant stress and disease susceptibility. Norway spruce (Picea abies (L.) H. Karst.), a key conifer species in European forestry, is particularly vulnerable. Developing innovative seed treatments to enhance tree resilience is crucial for sustainable forest management. Despite the growing interest in cold plasma (CP) technology for seed treatment, research on its long-term effects on trees, particularly Norway spruce, remains scarce. This study aimed to investigate the effects of pre-sowing CP treatment on Norway spruce seeds from 10 half-sib families over two vegetation seasons. Results indicate that CP treatment influenced key physiological and biochemical parameters in a genotype-specific and treatment duration-dependent manner (1 or 2 min). In some cases, CP-treated seedlings exhibited increased chlorophyll levels (e.g., increased chlorophyll a by up to 49% in some genotypes treated with CP for 1 min, and by up to 35% in those treated with CP for 2 min), reduced malondialdehyde (MDA) content in second-year samples (by up to 52% in some genotypes), and enhanced production of phenolics (by up to 21% in some genotypes in both treatment groups), suggesting improved stress tolerance. The 541 half-sib family is particularly noteworthy, as first-year seedlings exhibited increased levels of chlorophylls, flavonoids, and total phenols following a 2 min treatment. In contrast, second-year seedlings of the same family showed an increase in flavonoids and a reduction in MDA levels compared to the control, indicating a sustained and possibly age-modulated physiological response to CP exposure (2 min). However, responses varied across genetic backgrounds, highlighting the importance of genotype in determining treatment efficacy. These findings underscore the potential of CP technology as a tool for improving Norway spruce resilience and inform future strategies for seed enhancement in forestry. Full article

A Codonopsis pilosula film-laying and outcrop transplantation machine is developed to solve problems, such as unstable quality of transplanted seedlings, high intensity of manual work, and low efficiency of work in the seedling transplantation of Codonopsis pilosula. This paper outlines the structure and working principle of the machine and analyzes the key components of the prototype, designs the seed bed preparer, analyzes its working process and the force required for furrowing into the soil. Additionally, based on EDEM discrete element simulation technology, a soil-component simulation model was established. In addition, the Hertz–Mindlin model was selected as the contact model between the discrete element simulation soil particles and the seed bed preparer to simulate the operation process of the seed bed preparer. The structure and relevant parameters of the seedling planting device and soil covering device are determined, the transmission system scheme is established, and the working mechanism of the core components is analyzed. Field experiment results indicate that at forward speeds of 0.20, 0.25, and 0.3 m/s, the average qualified rate of planting depth is 91.08%, and the average qualified rate of plant spacing is 89.8%. The field performance test indicators met national and industry standards, which require both qualified rates to exceed 80%, and the test results met the design requirements, demonstrating the integrated operation of trenching, seedling planting, film-laying, and topsoil covering. Full article

Salinity is one of the main environmental factors influencing rice production. Many genes affecting salt tolerance (ST) have been cloned in rice so far. In the present study, four genes negatively regulating ST, including HST1, LRRK1, STRK2, and PC1, were edited by CRISPR-Cas9 technology in six rice varieties (three in indica (xian) and three in japonica (geng) backgrounds), and three two-gene editing combinations, including hst1-lrrk1, hst1-strk2, and hst1-pc1, were created. All combinations of hst1-pc1, hst1-lrrk1, and hst1-strk2 significantly improved the ST of all the tested materials in both xian and geng backgrounds and had much better ST than single-gene editing lines. The combination of hst1-pc1 had the poorest ST in CH70 and 8TX23 backgrounds but showed almost the same level of ST as the combinations of hst1-strk2 and hst1-lrrk1 in the C199S background for 17 days after salinization, which clearly brought out the background effect on ST and its utilization in ST breeding. As a comparison of the recipient varieties, almost all gene-edited lines except hst1-pc1 in the CH70 background showed significantly reduced grain weight owing to reduced seed setting rate in normal conditions. The hst1-strk2 showed the highest level of ST at the seedling stage and a relatively higher grain yield among all the lines; thus, it is feasible to enhance the ST of high-yielding rice varieties by simultaneously gene-editing against the two loci or pyramiding these two alleles with the other major ST genes of rice. Our results provide valuable gene resources and germplasms for improving rice salt tolerance and high yield. Full article

Drought stress is one of the key environmental factors restricting the germination of alfalfa seeds (Medicago sativa L.). Nanopriming is an innovative seed-priming technology able to meet economic, agronomic, and environmental needs in agriculture. However, the use of conventional nanomaterials is hampered by high costs, environmental risks, and biotoxicity. In this study, we synthesized iron oxide nanoparticles (Fe₃O₄NPs) using seasonal Ginkgo biloba leaf extracts (collected from August to November) obtained via an enzymatic ultrasonic-assisted method. The synthesized Fe₃O₄NPs were characterized using SEM, EDS, DLS, FTIR, UV-Vis, and XRD. To investigate the effects of Fe₃O₄NP priming on alfalfa seed germination under drought stress, germination and pot experiments were conducted with five Fe₃O₄NP priming concentrations (unprimed, 0, 20, 40, and 60 mg/L) and three PEG-6000 concentrations (0%, 10%, and 15%) to simulate normal, moderate, and severe drought conditions. The results showed that leaf extracts collected in November exhibited the highest flavonoid content (12.8 mg/g), successfully yielding bioactive-capped spherical Fe₃O₄NPs with a particle size of 369.5 ± 100.6 nm. Germination experiments revealed that under severe drought stress (15% PEG-6000), the 40 mg/L Fe₃O₄NP treatment most effectively enhanced seed vigor, increasing the germination rate, vigor index, and α-amylase activity by 22.1%, 189.4%, and 35.5% (p < 0.05), respectively, compared to controls. Under moderate drought stress (10% PEG-6000), the 20 mg/L Fe₃O₄NP treatment optimally improved germination traits, increasing the germination rate by 25.5% and seedling elongation by 115.6%. The pot experiments demonstrated morphological adaptations in alfalfa seedlings: under moderate drought stress, the 40 mg/L Fe₃O₄NPs significantly increased lateral root numbers, while under severe drought stress, the 60 mg/L Fe₃O₄NPs increased the root surface area by 20.5% and preserved the roots’ structural integrity compared to controls. These findings highlight that Fe₃O₄NPs synthesized via Ginkgo leaf extracts and enzymatic ultrasonic methods exhibit promising agricultural potential. The optimal Fe₃O₄NP priming concentrations enhanced seed vigor, germination traits, and drought resistance by modulating root morphology, with concentration-specific efficacy under varying drought intensities. Full article

The direct-seeded rice (DSR) system is poised to become the dominant rice cultivation method due to its advantages, including reduced water usage, less labor requirements, decreased greenhouse gas emissions, and improved adaptation to climate change. However, weeds, particularly jungle rice (Echinochloa colona), significantly hinder DSR and cause substantial yield losses. This study aimed to develop rice cultivars competitive against jungle rice through selective breeding, focusing on early seed germination (ESG) and seedling vigor (ESV). We utilized 181 early-backcross selective introgression breeding lines (EB-SILs) developed using Green Super Rice (GSR) technology by backcrossing Weed Tolerant Rice1 (WTR1) with three donor parents, Haoannong, Cheng Hui 448, and Y134. Using the tunable genotyping-by-sequencing (tGBS^®, Data2Bio Technologies, Ames, IA, USA) method, we identified 3971 common single nucleotide polymorphisms (SNPs) that facilitated the mapping of 19 novel quantitative trait loci (QTLs) associated with weed competitiveness—eight linked to ESG traits and eleven to ESV traits. Notably, all QTLs were novel except qRPH1, linked to relative plant height at 14 and 21 days after sowing. Key QTLs were located on chromosomes 2, 3, 5, 6, 8, 9, 10, and 12. Candidate genes identified within these QTLs are implicated in the plant’s response to various abiotic and biotic stresses. Our findings enhance the understanding of the genetic basis for ESG and ESV traits critical for weed competitiveness, supporting marker-assisted and genomic selection approaches for breeding improved rice varieties. Furthermore, this research lays the groundwork for employing gene expression, cloning, and CRISPR editing strategies to combat jungle rice, with potential applications for other weed species and contributing to effective integrated weed management in the DSR system. Full article

Auxin plays a versatile role in regulating plant growth and development. The auxin efflux carrier PIN-FORMED (PIN) proteins dictate the distribution and maximum of auxin within various tissues. Despite extensive research on OsPINs in recent years, their functions in abiotic stress resistance, particularly cold tolerance, remain poorly understood. Here, we investigated the role of OsPIN5b in rice (Oryza sativa L.) growth and development, as well as its contribution to cold tolerance using overexpression technology. Overexpression of OsPIN5b (OE) resulted in reduced shoot height and a lower number of adventitious roots at the seedling stage. Transgenic rice plants exhibited an earlier heading date, stunted growth, and compromised agronomic traits, including shortened panicle length, decreased grain number per panicle, reduced seed size, and lower seed setting rate during the reproductive stage. Auxin content in the transgenic lines was significantly elevated, as indicated by the upregulation of the auxin-responsive gene OsIAA20 and increased auxin levels quantified using a newly developed method. Compared with wild-type plants, the cold tolerance of OE plants was markedly reduced, as evidenced by lower survival rates, higher levels of electrolyte leakage, and increased malondialdehyde (MDA) production following cold treatment. In line with this, the transgenic lines produced less soluble sugar and proline, while accumulating more hydrogen peroxide (H₂O₂) and superoxide anion radicals (${\mathrm{O}}_2^{-}$) after cold treatment. Furthermore, the activities of antioxidant enzymes, including catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD), were notably decreased upon cold treatment compared with those in WT plants. Additionally, OsRBOHH, which plays a role in ROS production, was significantly upregulated in transgenic lines both before and after chilling stress, suggesting that OsRBOHH plays a potential role in regulating ROS production. Collectively, overexpression of OsPIN5b substantially disturbs auxin homeostasis, resulting in impaired plant architecture and agronomic traits. More importantly, the upregulation of OsPIN5b compromises rice cold tolerance by perturbing ROS homeostasis and adversely influencing the accumulation of soluble sugar and proline. Full article

Global food demand and insecurity are intensifying due to rapid population growth, the loss of arable land, climate change, and pollution. Among the critical challenges in global agriculture is soil salinization, in which high NaCl concentrations can severely inhibit germination and crop establishment. Cakile maritima, a halophyte from the Brassica genus, can tolerate salinity levels up to 400 mM NaCl, far exceeding the tolerance of most crops, making it a promising model for studying salt stress resistance. This study investigates the effects of seed halopriming as an effective strategy to enhance salt tolerance in C. maritima. The research evaluates germination rates, seedling establishment, mineral status, oxidative stress markers, and genetic responses under increasing NaCl concentrations. Halopriming with NaCl pre-activates the plant’s antioxidant defence mechanisms and upregulates stress-responsive genes, improving the plant’s resilience to saline conditions. While salinity caused significant physiological challenges, primed seeds demonstrated superior performance compared to non-primed controls, with enhanced germination and an improved tolerance to oxidative stress. These findings underscore the potential of halopriming as a cost-effective and sustainable technique to improve crop performance in saline environments. This study highlights the importance of advancing seed priming technologies for developing resilient crops to address global food security challenges in the face of climate change. Full article

Plasma-assisted treatment is a potentially interesting technology for advanced seed processing. In this work, we address the issue of defining and quantifying the plasma dose during the exposure of seeds to microdischarges formed in a barrier discharge configuration fed with synthetic air at atmospheric pressure. Using advanced imaging and other optoelectrical diagnostics, we identify suitable conditions for the formation of microdischarges developing exclusively between the powered electrode and the seed coat, which allows for the relatively accurate quantification of the plasma dose for an individual barley seed. In addition to determining the microdischarge energy/power consumed to treat a single seed during controlled exposure, we also provide an estimate of the electric field and gas temperature, which are key parameters that can affect seed viability. In this way, each individually exposed seed can be linked to the exact exposure time, total number, energy, and temperature of the microdischarges that came into contact with it. This is fundamentally different from conventional “averaging” approaches based on the simultaneous exposure of many seeds, which makes it virtually impossible to correlate the responses of individual seeds with the corresponding individual plasma dose. Finally, we propose a minimal treatment protocol that could allow for the more direct interpretation of the results of subsequent biological tests to reveal seed responses to specific plasma–chemical stimuli during germination and seedling growth. Full article

The submergence tolerance of rice is a key factor in promoting rice direct seeding technology and resisting flood disasters. Dongxiang wild rice (DXWR) has strong submergence tolerance, but its genetic basis is still unclear. Here, we report quantitative trait loci (QTLs) analysis for hypoxic germination rate (HGR), hypoxic seedling rate (HSR), budlet submergence survival rate (BSSR) and seedling submergence survival rate (SSSR) using a linkage map in the backcross recombinant inbred lines (BRILs) that were derived from a cross of DXWR, and an indica cultivar, GZX49. A total of 20 QTLs related to submergence tolerance of rice were detected, explaining phenotypic variations ranging from 2% to 8.5%. Furthermore, transcriptome sequencing was performed on the seeds and seedlings of DXWR before and after submergence. During the seed hypoxic germination and seedling submergence stages, 6306 and 3226 differentially expressed genes (DEGs) were detected respectively. Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) analyses were conducted on these differentially expressed genes. Using genetic linkage analysis and transcriptome data, combined with qRT-PCR, sequence comparison, and bioinformatics, LOC_Os05g32820 was putatively identified as a candidate gene for qHGR5.2 co-located with HGR and SSSR. These results will provide insights into the mechanism of rice submergence tolerance and provide a basis for improving rice submergence tolerance. Full article

Systemic fluorescence tracers introduced into crop plants provide an active signal for crop–weed differentiation that can be exploited for precision weed management. Rhodamine B (RB), a widely used tracer for seeds and seedlings, possesses desirable properties; however, its application as a seed treatment has been limited due to potential phytotoxic effects on seedling growth. Therefore, investigating mitigation strategies or alternative systemic tracers is necessary to fully leverage active signaling for crop–weed differentiation. This study aimed to identify and address the phytotoxicity concerns associated with Rhodamine B and evaluate Rhodamine WT and Sulforhodamine B as potential alternatives. A custom 2D fluorescence imaging system, along with analytical methods, was developed to optimize fluorescence imaging quality and facilitate quantitative characterization of fluorescence intensity and patterns in plant seedlings, individual leaves, and leaf disc samples. Rhodamine compounds were applied as seed treatments or in-furrow (soil application). Rhodamine B phytotoxicity was mitigated by growing in a sand and perlite media due to the adsorption of RB to perlite. Additionally, in-furrow and seed treatment methods were tested for Rhodamine WT and Sulforhodamine B to evaluate their efficacy as non-phytotoxic alternatives. Experimental results demonstrated that Rhodamine B applied via seed pelleting and Rhodamine WT used as a direct seed treatment were the most effective approaches. A case study was conducted to assess fluorescence signal intensity for crop–weed differentiation at a crop–weed seed distance of 2.5 cm (1 inch). Results indicated that fluorescence from both Rhodamine B via seed pelleting and Rhodamine WT as seed treatment was clearly detected in plant tissues and was ~10× higher than that from neighboring weed plant tissues. These findings suggest that RB ap-plied via seed pelleting effectively differentiates plant seedlings from weeds with reduced phytotoxicity, while Rhodamine WT as seed treatment offers a viable, non-phytotoxic alternative. In conclusion, the combination of the developed fluorescence imaging system and RB seed pelleting presents a promising technology for crop–weed differentiation and precision weed management. Additionally, Rhodamine WT, when used as a seed treatment, provides satisfactory efficacy as a non-phytotoxic alternative, further expanding the options for fluorescence-based crop–weed differentiation in weed management. Full article

Quantifying planting layouts during the seedling stage of mung beans (Vigna radiata L.) is crucial for assessing cultivation conditions and providing support for precise management. Traditional information extraction methods are often hindered by engineering workloads, time consumption, and labor costs. Applying deep-learning technologies for information extraction reduces these burdens and yields precise and reliable results, enabling a visual analysis of seedling distribution. In this work, an unmanned aerial vehicle (UAV) was employed to capture visible light images of mung bean seedlings in a field across three height gradients of 2 m, 5 m, and 7 m following a time series approach. To improve detection accuracy, a small target detection layer (p2) was integrated into the YOLOv8-obb model, facilitating the identification of mung bean seedlings. Image detection performance and seedling information were analyzed considering various dates, heights, and resolutions, and the K-means algorithm was utilized to cluster feature points and extract row information. Linear fitting was performed via the least squares method to calculate planting layout parameters. The results indicated that on the 13th day post seeding, a 2640 × 1978 image captured at 7 m above ground level exhibited optimal detection performance. Compared with YOLOv8, YOLOv8-obb, YOLOv9, and YOLOv10, the YOLOv8-obb-p2 model improved precision by 1.6%, 0.1%, 0.3%, and 2%, respectively, and F1 scores improved by 2.8%, 0.5%, 0.5%, and 3%, respectively. This model extracts precise information, providing reliable data for quantifying planting layout parameters. These findings can be utilized for rapid and large-scale assessments of mung bean seedling growth and development, providing theoretical and technical support for seedling counting and planting layouts in hole-seeded crops. Full article

To address the challenges of labor-intensive, inefficient, and inconsistent manual hole sowing and transplanting of Angelica sinensis in rain-fed hilly regions of Northwest China, a pneumatic hole-sowing device was designed based on the principle of electromagnetically controlled, high-speed reciprocating cylinder motion. Considering the agronomic requirements for transplanting mulched Angelica sinensis, the device’s structure and operational parameters were optimized. The key mechanisms involved in hole sowing and seedling placement were analyzed. A pneumatic circuit system, controlled by a relay circuit, was established, and a hole-sowing mechanism with a delayed closure effect was designed. Using the Discrete Element Method (DEM) and Multi-Body Dynamics (MBD) coupling technology, a simulation of the hole-sowing process was conducted to evaluate the device’s performance and its impact on soil disturbance and hole reformation in the seedbed. Prototype device performance tests were conducted, using qualified seeding depth under mulch and hole spacing as indicators. When the theoretical hole spacing was 30 cm and the hole-sowing frequency was 60 plants/(min·row), the soil bin test results indicated a seeding depth qualification rate of 93%, a misalignment rate of 3%, and a spacing qualification rate of 83%; the field test results showed a qualified seeding depth rate under mulch of 96%, the hole misalignment rate was 5%, and the spacing qualified rate was 86%. The pneumatic hole-sowing device’s performance meets the agronomic requirements for vertical transplanting of Angelica sinensis seedlings. This research can serve as a reference for designing planting machinery for rhizomatous medicinal plants. Full article

Seed coating technology is vital in agriculture, enhancing seed protection and growth. However, conventional coatings often include chemical fungicides that pose environmental risks, highlighting the need for sustainable alternatives. This study explores silk fibroin (SF), a natural biopolymer with excellent film-forming properties, as a potential seed coating agent, addressing its antimicrobial limitations by combining it with the commercial agent CRUISER^® and the antimicrobial peptide Nisin. Experimental methods included solution stability analysis, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), and growth assessments of wheat seeds. Findings reveal that silk fibroin-CRUISER^® (SC) composites form stable β-sheet structures, enhancing the coating’s mechanical strength. SF-based coatings improved seedling emergence rates (up to 1.65-fold), plant height (up to 1.05-fold), and root growth (up to 1.2-fold), especially under cold stress. The addition of Nisin further significantly boosted the antibacterial properties, providing sustained pathogen inhibition (p < 0.01). Identifying the optimal concentration of SF was essential for achieving a balance between protection and breathability, a key factor for industrial application. This research provides valuable insights into the development of eco-friendly seed coatings, presenting a viable and sustainable alternative to traditional chemical-based options in agricultural practices. Full article

The uniformity of the wheat distribution within and between rows has a significant effect on crop population structure, leading to decreased yield as nonuniformity increases. Traditional drills are influenced by soil porosity and flatness in the field, making accurate control of sowing depth and amount challenging and resulting in an uneven spatial distribution of gramineous seedlings. Precision cave-sowing technology effectively enhances wheat population distribution uniformity. However, owing to limitations in existing mechanical precision cave planters, their operational speed is lower than that of drill planters. To address these issues, this study designed an air-suction precision wheat seed dispenser, described its basic structure and working principle, and developed a seed mechanical model. A theoretical analysis was conducted on the working process and key components of the seed feeder. A suitable mould hole diameter was determined to be 1.6~2.0 mm, and the rotation speed range for the seed plate was found to be 65~85 r·min⁻¹. Fluent simulations were used to determine the influence of orifice type on gas chamber flow fields; DEM-CFD-coupled simulation identified an appropriate negative pressure range of 2.6~3.4 kPa for optimal performance during seeding operations. Orthogonal experiments were carried out with mould hole diameter, negative pressure size, and seed plate speed as test factors alongside a qualification index, multiple sowing index, and missed sowing index as response indicators—leading to regression equation establishment, which yielded the optimal parameter combination: mould hole diameter at 1.8 mm; gas chamber negative pressure at 3.2 kPa; and a seed plate speed of 74 r·min⁻¹, with the corresponding forwards speed of the machine being 7 km·h⁻¹—resulting in a qualification index of 91.66%, multiple sowing index of 5.98%, and missed sowing index of 2.36%. This pneumatic suction type wheat precision seeder achieves equivalent operational speeds as traditional drills while enabling precision seeding. Full article