Search Results (215)

Accurate and timely estimation of soybean emergence at the plot scale using unmanned aerial vehicle (UAV) remote sensing imagery is essential for germplasm evaluation in breeding programs, where breeders prioritize overall plot-scale emergence rates over subimage-based counts. This study proposes PlotCounter, a deep learning regression model based on the TasselNetV2++ architecture, designed for plot-scale soybean seedling counting. It employs a patch-based training strategy combined with full-plot validation to achieve reliable performance with limited breeding plot data. To incorporate additional agronomic information, PlotCounter is extended into a multitask learning framework (MTL-PlotCounter) that integrates sowing metadata such as variety, number of seeds per hole, and sowing density as auxiliary classification tasks. RGB images of 54 breeding plots were captured in 2023 using a DJI Mavic 2 Pro UAV and processed into an orthomosaic for model development and evaluation, showing effective performance. PlotCounter achieves a root mean square error (RMSE) of 6.98 and a relative RMSE (rRMSE) of 6.93%. The variety-integrated MTL-PlotCounter, V-MTL-PlotCounter, performs the best, with relative reductions of 8.74% in RMSE and 3.03% in rRMSE compared to PlotCounter, and outperforms representative YOLO-based models. Additionally, both PlotCounter and V-MTL-PlotCounter are deployed on a web-based platform, enabling users to upload images via an interactive interface, automatically count seedlings, and analyze plot-scale emergence, powered by a multimodal large language model. This study highlights the potential of integrating UAV remote sensing, agronomic metadata, specialized deep learning models, and multimodal large language models for advanced crop monitoring. Full article

The hard-seed coat of Ormosia henryi significantly impedes germination efficiency in massive propagation, while conventional physical dormancy-breaking methods often result in compromised seed vigor, asynchronous seedling emergence, and diminished stress tolerance. Seed biopriming, an innovative technique involving the inoculation of beneficial microorganisms onto seed surfaces or into germination substrates, enhances germination kinetics and emergence uniformity through microbial metabolic functions and synergistic interactions with seed exudates. Notably, spermosphere-derived functional bacteria isolated from native spermosphere soil demonstrate superior colonization capacity and sustained bioactivity. This investigation employed selective inoculation of these indigenous functional strains to systematically analyze dynamic changes in endogenous phytohormones, enzymatic activities, and storage substances during critical germination phases, thereby elucidating the physiological mechanisms underlying biopriming-enhanced germination. The experimental results demonstrated significant improvements in germination parameters through biopriming. Inoculation with the Bacillus sp. strain achieved a peak germination rate (76.19%), representing a 16.19% increase over the control (p < 0.05). The biopriming treatment effectively improved the seed vigor, broke the impermeability of the seed coat, accelerated the germination speed, and positively regulated physiological indicators, especially amylase activity and the ratio of gibberellic acid to abscisic acid. This study establishes a theoretical framework for microbial chemotaxis and rhizocompetence in seed priming applications while providing an eco-technological solution for overcoming germination constraints in O. henryi cultivation. The optimized biopriming protocol addresses both low germination rates and post-germination growth limitations, providing technical support for the seedling cultivation of O. henryi. Full article

Seed germination, a pivotal stage in the plant life cycle, profoundly impacts crop growth and establishment. However, fluctuating environmental conditions like drought, salinity, severe temperatures, and heavy metal toxicity impede seed germination rates and seedling vigor. Seed priming is a pre-sowing seed treatment that involves the controlled hydration of seeds, proven to improve germination rate and stress resilience. It initiates pre-germinative metabolism, including enzyme activity, antioxidant accumulation, hormone modulation, and cellular repair, without radicle emergence. Recent advancements in seed priming, encompassing the application of nanoparticles, phytohormones, and beneficial microbes, have significantly broadened its potential. Despite its proven benefits, challenges such as reduced seed longevity post-priming and variability in species-specific responses remain. This paper revisits the principles and methodologies of seed priming, highlighting its physiological, biochemical, and molecular mechanisms that enhance germination under stress conditions. Additionally, it addresses current challenges and future research directions for optimizing seed priming as a low-cost, eco-friendly approach to improve crop establishment under adverse environments, thereby supporting resilient and sustainable agriculture. Full article

As an emerging vegetable cultivation technology, plug seedling cultivation significantly improves seedling production efficiency and reduces costs through standardization. Grading and transplanting, as the final step before the sale of plug seedlings, categorizes seedlings into different grades to ensure consistent quality. However, most current grading methods can only detect seedling emergence but cannot classify the emerged seedlings. Therefore, this study proposes an intelligent grading method for pepper plug seedlings based on RGB and point cloud images, enabling precise grading using both RGB and 3D point cloud data. The proposed method involves the following steps: First, RGB and point cloud images of the seedlings are acquired using 2D and 3D cameras. The point cloud data is then converted into a 2D representation and aligned with the RGB images. Next, a deep learning-based object detection algorithm identifies the positions of individual seedlings in the RGB images. Using these positions, the seedlings are segmented from both the RGB and 2D point cloud images. Subsequently, a deep learning-based leaf recognition algorithm processes the segmented RGB images to determine leaf count, while another deep learning-based algorithm segments the leaves in the 2D point cloud images to extract their spatial information. Their surface area is measured using 3D reconstruction method to calculate leaf area. Additionally, plant height is derived from the point cloud’s height data. Finally, a classification model is trained using these extracted features to establish a grading system. Experimental results demonstrate that this automated grading method achieves a success rate of 97%, and compared with manual methods, this method has higher production efficiency. Meanwhile, it can grade different tray seedlings by training different models and provide reliable technical support for the quality evaluation of seedlings in industrialized transplanting production. Full article

The growing global demand for food has driven an increase in both swine and agricultural production, although swine wastewater poses a significant environmental risk. This study employed elemental mapping techniques to evaluate the effects of swine wastewater irrigation on the spatial distribution and concentration of essential and non-essential elements, as well as on the morphological responses of habanero pepper (Capsicum chinense Jacq.) seedlings. Six treatments were tested, ranging from 0% to 100% swine wastewater (T1 = 20%, T2 = 40%, T3 = 60%, T4 = 80%, T5 = 100%, and T6 = control with conventional fertilization), using a completely randomized design with five replications. Emergence, elemental distribution, morphology, and seedling quality were evaluated. The highest emergence percentages and rates were observed in the 20% wastewater treatment and the control groups. Diluted wastewater treatments promoted potassium and calcium uptake, which correlated with improved seedling growth and vigor, while irrigation with 100% wastewater led to excessive chlorine and sulfur accumulation, negatively affecting morphology. These results indicate that the controlled dilution of swine wastewater optimizes nutrient availability and seedling development, offering an environmentally sustainable alternative for producing high-quality habanero pepper seedlings. This study provides novel insights into the environmental implications of swine wastewater reuse through elemental mapping, underscoring its potential to support sustainable and regenerative agriculture. Full article

Appropriate deep sowing holds significant potential in enhancing wheat production, particularly in dry and low-rainfall regions. Henan Province is a major winter wheat-producing area in China; evaluating the adaptability of wheat varieties to deep sowing through scientific methods is crucial to improve wheat production. This study investigates 26 wheat cultivars in Henan. By assessing key traits of seeds and seedlings at various sowing depths, we analyzed the effects of sowing depth on seed germination and seedlings. A comprehensive index for deep sowing tolerance was established using principal component analysis (PCA) and the membership function method, followed by the classification of the varieties according to their tolerance to deep sowing. The results indicated that, with increased sowing depth, seedling emergence time, coleoptile length, and coleoptile internode length increased, while seedling emergence rate, seedling height, leaf area, and shoot dry weight per unit area decreased. Based on PCA and membership function values, the 26 wheat varieties were classified into three categories: deep sowing tolerant, moderately tolerant, and intolerant, comprising 3, 19, and 4 varieties. This study provides valuable insights for optimizing wheat variety selection and improving sowing practices in Henan Province, offering both theoretical and practical contributions to local wheat production. Full article

Conventional micropropagation of cannabis struggles with excessive callus hyperhydration, slow growth, low rooting efficiency, and high contamination risk, all of which greatly restrict its feasibility for large-scale propagation. In contrast, photoautotrophic micropropagation (PAM) has emerged as an efficient and cost-effective propagation strategy that can significantly enhance plantlet growth and improve seedling quality by optimizing the LED lighting environment. This study investigated the effects of four light intensities (50, 100, 150, and 200 µmol m⁻² s⁻¹) and three photoperiods (16, 20, and 24 h d⁻¹) on the growth and rooting of two medicinal cannabis cultivars (the short-day cultivar ‘Charlotte’ and the day-neutral cultivar ‘Auto Charlotte’). Cluster analysis revealed that plantlets grown under the photoperiod of 20 h d⁻¹ and light intensity of 100–150 µmol m⁻² s⁻¹ exhibited optimal growth performance in terms of plant height, root length, leaf number, leaf area, biomass, and root activity. Moreover, increasing the light intensity from 50 to 100–150 µmol m⁻² s⁻¹ significantly enhanced net CO₂ exchange rates by 41.5% and 204.9% for Charlotte and Auto Charlotte, respectively, along with corresponding increases in dry matter accumulation of 44.3% and 27.9%. However, the plantlets exhibited photooxidative damage under continuous lighting and light intensity of 200 µmol m⁻² s⁻¹, as evidenced by reduced photosynthetic pigment content and suppressed antioxidant enzyme activity. Therefore, PAM of medicinal cannabis is recommended under the LED lighting environment with light intensity of 100–150 µmol m⁻² s⁻¹ and photoperiod of 20 h d⁻¹ to achieve optimal growth and rooting. These findings provide essential technical support for the large-scale propagation of vigorous, disease-free female plantlets with well-developed root systems and high genetic uniformity, thereby meeting the stringent quality standards for planting materials in the commercial cultivation of cannabis for medical and pharmaceutical use. Full article

Soil compaction is a well-known harmful process for germination and seedling growth. Studies about compaction in mining tailings have been neglected despite being essential for the reforestation of impacted areas. This work evaluated the effects of compaction of iron mining tailings on the seedling emergence, early growth, and photosynthesis of Schinus terebinthifolia Raddi, a tolerant species with potential for reforestation. Experiments were implemented in a greenhouse where seeds of S. terebinthifolia were sown in iron mining tailings with four compaction treatments: (1) an uncompacted dry tailing, (2) uncompacted moistened tailing, (3) compacted dry tailing, and (4) compacted moistened tailing. Penetration resistance, seedling emergence, emergence speed index, seedling biometry, and photochemical traits were evaluated. Compacted moistened tailings showed the highest penetration resistance and uncompacted dry tailings the lowest. Other treatments showed intermediate means. The compacted moistened tailings produced the lowest seedling emergence rate and emergence speed index, and these parameters showed the highest means at uncompacted dry tailings with other treatments showing intermediate means. The compaction did not affect the seedling’s biometric parameters, with a similar growth among all treatments. S. terebinthifolia seedlings showed improved growth parameters during the experimental period, evidencing the potential of the species for the reforestation of impacted areas by iron mining tailings. Full article

Drought stress is one of the main factors limiting seed germination and seedling establishment in field crops such as jalapeño peppers (Capsicum annuum L.). Nanopriming, a seed improvement technique using nanoparticle suspensions, has emerged as a sustainable approach to improving water use efficiency during the early stages of development. This study evaluated the effects of zinc oxide (ZnO, 100 mg·L⁻¹), silicon dioxide (SiO₂, 10 mg·L⁻¹), and their combination (ZnO + SiO₂), stabilized with chitosan, on the germination yield and drought tolerance of jalapeño seeds under mannitol-induced water stress (0%, 15%, and 30%). Compared to the hydroprimed control (T1), nanoparticle treatments consistently improved seed yield. Priming with ZnO (T2) increased the germination percentage by up to 25%, priming with SiO₂ (T3) improved the germination rate by 34%, and the combined treatment (T4: ZnO + SiO₂) improved the fresh weight of the seedlings by 40%. Proline accumulation increased 7.5 times, antioxidant capacity (DPPH) increased 6.5 times, and total phenol content increased 4.8 times in the combined treatment. Flavonoid levels also showed notable increases, suggesting enhanced antioxidant defense. These results clearly demonstrate the superior efficacy of nanoparticle pretreatment compared to conventional hydraulic pretreatment, especially under drought conditions. Multivariate analysis further highlighted the synergistic role of ZnO and SiO₂ in improving osmolite accumulation, antioxidant activity, and water use efficiency. Nanopriming with ZnO and SiO₂ offers a promising, economical, and scalable strategy to improve germination, early growth, and drought resistance in jalapeño pepper cultivation under semi-arid conditions. Full article

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

The sexual reproduction of Sasa borealis, a species of dwarf bamboo, occurred in central Japan from 2016 to 2017. S. borealis grows on the forest floor and serves as an important source of habitat and food for various animals. Sexual reproduction occurs in synchrony among individuals in a given area, leading to a decline in population and causing substantial disturbances to the forest ecosystem; however, the subsequent regeneration process remains unclear. In this study, we investigated S. borealis seedling regeneration over six years. Fixed plots were established in the forest in the year following the sexual reproductive event, and the growth of seedlings was monitored from seed emergence to seedling growth at the individual level. We considered biotic and abiotic factors to evaluate their influence on regeneration. We examined mammalian and arthropod foraging as biotic factors. Conversely, abiotic factors included temperature and humidity near the ground surface, solar radiation, soil conditions, and snow cover. Seedling growth was characterized by a slow rate and affected by morphological changes resulting from foraging and abiotic factors. The return of S. borealis to its presexual reproductive stage requires an extended duration. Our study provides precious information for future S. borealis conservation and management strategies. Full article

Soil salinization has emerged as a significant global threat to agricultural productivity. Rice is susceptible to salinity stress at the seedling stage. However, the mechanisms underlying rice responses to salinity stress remain incompletely characterized. In this study, we have characterized a transfer DNA (T-DNA) insertion mutant line of rice, designated OsVPS16 (Os12g0594200), to elucidate its functional role in salt stress tolerance. A real-time quantitative PCR (RT-qPCR) analysis revealed that salt stress inhibited the expression of OsVPS16, with the vps16 mutant showing negligible expression levels. A phenotypic analysis showed that the loss of OsVPS16 enhanced primary root elongation, and increased the survival rate to improve salt stress tolerance. Compared to the wild type (DJ), the vps16 mutant accumulated less Na⁺ and more K⁺ in the shoots under salt stress. Furthermore, the vps16 mutant displayed decreased malondialdehyde (MDA) accumulation and enhanced the activities of superoxide dismutase (SOD) and peroxidase (POD) under salt stress. Transcriptomic profiling identified 1236 differentially expressed genes (DEGs) between vps16 and DJ roots under salt stress. A functional enrichment analysis revealed that DEGs were enriched in protein serine/threonine kinase activity, Ca²⁺ signal pathways, and the MAPK signaling pathway. Notably, the up-regulation of critical protein kinases (PKs) and transcription factors (TFs), including OsSRK1, OsCDPK21, and OsNAC45, probably adds to the effect of OsVPS16 mutation to account for salt stress tolerance. Collectively, comprehensive physiological and molecular analyses demonstrated that the loss of OsVPS16 improves rice salt tolerance through multiple mechanisms, including the regulation of K⁺/Na⁺ homeostasis, the modulation of antioxidant enzyme activities, and the transcriptional reprogramming of stress-responsive genes. This study not only elucidates the function of a novel salt stress response gene in rice, but also provides valuable genetic resources for developing salt-tolerant rice cultivars through molecular breeding approaches. Full article

The Separately Collected Organic Fraction of Municipal Solid Waste (SC-OFMSW) is the biodegradable kitchen and canteen waste fraction that is separately collected at source and classified by the European Waste Catalogue under code 20 01 08. The utilization of SC-OFMSW Compost has emerged as a sustainable approach to enhancing agricultural soil quality and supporting soil biodiversity and productivity, while also serving as a viable option for disposing of treated urban waste. This study investigates the dose effect of SC-OFMSWC through phytotoxicity and growth assays in Arabidopsis thaliana and Lactuca sativa seeds and seedlings, as well as the impact of the same compost on the chemical and microbiological properties of soil under open field conditions. During the field trial in an agricultural orchard, soil pH, nutrient content, organic matter, and microbial activity following SC-OFMSWC and chemical fertilizer application were evaluated. In the greenhouse trial, a significant increase in germination rate and biomass production was found for L. sativa at a compost concentration of 2.5%, while neutral to negative effects were observed for A. thaliana. In the open field, results indicated significantly increased levels of organic carbon and enhanced microbial biomass and activity, accompanied by a general increase in nutrients, promoting soil health and resilience, with only limited increases in EC values and heavy metal content. These findings underscore the potential of SC-OFMSWC as an effective agricultural soil improver and a promising component in sustainable nursery management practices. Full article

In this study, plasma-activated water (PAW) was generated using a large-volume (5 L) plasma reactor with a quasi-stationary, water-cathode glow-type discharge in atmospheric pressure air. Tap water was activated up to 75 min. PAW exhibited high concentrations of long-lived reactive nitrogen species (RNSs), reaching 8 mM, which is between 4 and 26 times higher than those reported in previous studies. The reactor reached an RNS synthesis efficiency of 61 nmol/J and an RNS production rate of 526 μmol/min, both among the highest reported. PAW was evaluated on tomato and bell pepper. Seedling emergence was determined in a nutrient-free substrate. To assess plant growth, seedlings were transplanted into pots filled with either nitrogen-free or nutrient-rich substrate. PAW-irrigation significantly promoted seedling emergence and leaf expansion, especially in tomato plants. The plant growth-stimulating effects of PAW were more pronounced in nitrogen-free substrate: fresh weight of tomato and bell pepper increased up to 13.1-fold and 2.6-fold, respectively. In contrast, the effect on the nutrient-rich substrate was negligible. Tomato plants grown in the nitrogen-free substrate and irrigated with 75-min PAW reached a dry weight comparable to those grown in nutrient-rich substrate. PAW irrigation did not induce oxidative stress, as confirmed by malondialdehyde (MDA) levels and antioxidant enzyme activity. Full article

Tall wheatgrass, a perennial forage grass renowned for its salt–alkali tolerance, has recently been proposed as a key species for planting in coastal saline–alkaline lands to establish a “Coastal Grass Belt”. Highly salt-tolerant and high-yielding varieties are essential to achieve this objective. To enhance breeding efficiency, a method integrating seed germination, seedling emergence, and seedling growth was established to evaluate salt tolerance in tall wheatgrass. Germination tests revealed that under 250 mM NaCl, 150 mM Na₂SO₄, 150 mM NaHCO₃, or 100 mM Na₂CO₃, the relative seed germination rates were 31.5%, 65.4%, 68.2%, and 32.6%, respectively, compared to the non-stress condition. Germination tests can use 250 mM NaCl and 100 mM Na₂CO₃ to assess tall wheatgrass tolerance to neutral and sodic salt stress, respectively. In addition, 250 mM NaCl or saline water with EC_w = 6.6 dS m⁻¹ resulted in relative seedling emergence rates of 52% and 59.8%, respectively, compared to the non-stress condition. Seedling hydroponic culture demonstrated that exposure to 300 mM NaCl resulted in relative total dry weight, shoot dry weight, and root dry weight of 38.2%, 35.7% and 50%, respectively, compared to the non-stress condition. Salt-response genes exhibited differential expression in tall wheatgrass under long-term and short-term salt stress. Interestingly, the expression levels of NHX7.1 and NCL1 were significantly higher in salt-tolerant lines compared to salt-sensitive lines. Based on an integrated evaluation of seed germination, seedling emergence, and seedling growth, five out of the 28 tall wheatgrass lines were identified as salt-tolerant. Additionally, two Tritipyrum lines, derived from the cross of Triticum aestivum cv. Xinong 6028 and Thinopyrum ponticum line Zhongyan 1, were found to inherit salt tolerance from tall wheatgrass. Collectively, this work provided an integrated method for salt tolerance testing in a tall wheatgrass breeding program. Full article