Search Results (291)

Potted cultivation serves as a vital strategy for industrialized production of standardized tree peonies, engineering seedlings capable of year-round and off-site transplantation. However, the limited root zone in potted conditions restricts root development, resulting in suboptimal seedling quality and hindering commercial-scale production. This study aimed to investigate the relationship between the accumulation characteristics of non-structural carbohydrates (NSCs) and growth performance in potted tree peonies, while also optimizing the transplantation technologies for potted cultivation. Using two-year-old grafted seedlings of ‘Luoyanghong’ as experimental material, the effects of root pruning, rooting agent, and Metarhizium anisopliae application on morphological development and NSCs accumulation in potted tree peony seedlings were investigated. The results showed that old roots serve as the primary storage organs for NSCs in the potted tree peony. Slight root pruning (25%) was beneficial for fibrous root growth, whereas excessive root pruning (50%) resulted in reduced biomass and NSCs accumulation. The application of a high concentration of rooting agents effectively promoted root growth and mitigated the adverse effects of root pruning. Furthermore, Metarhizium anisopliae significantly increased the stem number in potted tree peonies. The optimal protocol identified through range analysis involved 25% root pruning, followed by irrigation with a solution containing 750 mg·L⁻¹ rooting agent and 20 million spores·mL⁻¹ of Metarhizium anisopliae. The rational distribution of NSCs and coordinated growth across different organs enhanced NSCs accumulation in potted tree peonies. These results demonstrate that combining root pruning with the application of rooting agent and Metarhizium anisopliae can effectively increase NSCs accumulation, optimize plant morphology, and ultimately improve the quality of potted tree peony seedlings. Full article

Traditionally, mechanical bending tests are used to measure the stiffness of lumber, which is generally represented by the static modulus of elasticity (MoE). However, it is desirable to measure the stiffness of wood before it is processed into lumber. Acoustic nondestructive testing techniques are therefore the main techniques used by the wood industry to estimate the dynamic MoE of wood. The acoustic resonance technique is employed for measuring the MoE in felled logs and lumber. In contrast, the acoustic time-of-flight (ToF) technique is traditionally used for MoE measurements on standing trees and seedlings. However, the ToF technique overestimates stiffness compared to both resonance and static bending tests (considered the gold standard). In this work, a guided wave technique is used to measure the stiffness of wooden rods. This work is the first to compare the MoE values obtained using static bending tests (gold standard) with those obtained using acoustic resonance, ToF, and guided wave methods. Measurements were performed on 16 mm diameter radiata pine wooden rods. For comparison, measurements were also performed on acetal, aluminium, and steel rods of similar dimensions. The findings show that stiffness measurements obtained using the proposed guided wave method are more accurate than those obtained using the traditional ToF method and closely match those of the resonance method across all materials. The measurements from the ToF method were overestimated compared to resonance, guided wave, and static bending methods. The findings show the potential for the guided wave method to be used as an alternative method to provide more accurate stiffness measurements in juvenile trees/seedlings compared with the traditional ToF technique. Full article

Seedling transplantation, a pivotal component in advancing the cultivation of vegetables and cash crops, significantly bolsters crops’ resilience against drought, cold, pests, and diseases, while substantially enhancing yields. The implementation of transplanting machinery not only remarkably alleviates the labor-intensive nature of transplantation but also elevates the precision and uniformity of the process, thereby facilitating mechanized plant protection and harvesting operations. This article summarizes the research status and development trends of mechanized field transplanting technology and equipment. It also analyzes and summarizes the types and current status of typical representative automatic seedling picking mechanisms. Based on the current research status, the challenges of mechanized transplanting technology were analyzed, mainly the following: insufficient integration of agricultural machinery and agronomy; the standards for each stage of transplanting are not perfect; the adaptability of existing transplanting machines is poor; the level of informatization and intelligence of equipment is low; the lack of innovation in key components, such as seedling picking and transplanting mechanisms; and the proposed solutions to address the issues. Corresponding solutions are proposed, such as the following: strengthening interdisciplinary collaboration; establishing standards for transplanting processes; enhancing transplanter adaptability; accelerating intelligentization and digitalization of transplanters; strengthening the theoretical framework; and performance optimization of transplanting mechanisms. Finally, the development direction of future fully automatic transplanting machines was discussed, including the following: improving the transplanting efficiency and quality of transplanting machines; integrating research and development of testing, planting, and seedling supplementation for transplanting machines; unmanned transplanting operations; and fostering collaborative industrial development. Full article

In recent years, low temperature has seriously threatened the citrus industry. Arbuscular mycorrhizal fungi (AMF) can enhance the absorption of nutrients and water and tolerance to abiotic stresses. In this study, pot experiments were conducted to study the effects of low-temperature stress on citrus (trifoliate orange, Poncirus trifoliata L. Raf.) with AMF (Diversispora epigaea D.e). The results showed that AMF inoculation significantly increased plant growth, chlorophyll fluorescence, and photosynthetic parameters. Compared with 25 °C, −5 °C significantly increased the relative conductance rate and the contents of malondialdehyde, hydrogen peroxide, soluble sugar soluble protein, and proline, and also enhanced the activities of catalase and superoxide dismutase, but dramatically reduced photosynthetic parameters. Compared with the non-AMF group, AMF significantly increased the maximum light quantum efficiency and steady-state light quantum efficiency at 25 °C (by 16.67% and 61.54%), and increased the same parameters by 71.43% and 140% at −5 °C. AMF also significantly increased the leaf net photosynthetic rate and transpiration rate at 25 °C (by 54.76% and 29.23%), and increased the same parameters by 72.97% and 26.67% at −5 °C. Compared with the non-AMF treatment, the AMF treatment significantly reduced malondialdehyde and hydrogen peroxide content at 25 °C (by 46.55% and 41.29%), and reduced them by 28.21% and 29.29% at −5 °C. In addition, AMF significantly increased the contents of soluble sugar, soluble protein, and proline at 25 °C (by 15.22%, 34.38%, and 11.38%), but these increased by only 9.64%, 0.47%, and 6.09% at −5 °C. Furthermore, AMF increased the activities of superoxide dismutase and catalase at 25 °C (by 13.33% and 13.72%), but these increased by only 5.51% and 13.46% at −5 °C. In conclusion, AMF can promote the growth of the aboveground and underground parts of trifoliate orange seedlings and enhance their resistance to low temperature via photosynthesis, osmoregulatory substances, and their antioxidant system. Full article

The mismatch between the rapid expansion of breeding scale and outdated techniques has hindered the development of the sea cucumber (A. japonicus) industry. Our previous work revealed that ecological seedling breeding can produce red-colored A. japonicus, a phenotype not observed in traditional artificial breeding, where individuals are typically green. To investigate the molecular and genetic basis of this novel red coloration, we compared the growth conditions of red sea cucumbers and green sea cucumbers, as well as the differences in the pigment composition, gene expression and metabolites of their body walls. Red individuals showed higher body length and weight, and elevated levels of astaxanthin, lutein, canthaxanthin, and β-carotene in the body wall. Transcriptomic and metabolomic analyses identified differentially expressed genes and metabolites associated with pigmentation. In particular, FMO2 and WDR18, involved in the cytochrome P450 drug metabolism pathway, were significantly upregulated in red individuals and are known to play roles in pigment biosynthesis and light signal perception. Key metabolites such as astaxanthin and fucoxanthin were implicated in body color formation. Moreover, genes in the arachidonic acid metabolism pathway were highly expressed, suggesting that dietary factors may contribute to pigment synthesis and accumulation. These findings provide novel insights into the mechanisms underlying body color variation in A. japonicus and offer potential for improved breeding strategies. Full article

Idesia polycarpa is a valuable woody oil plant with potential for horticultural and industrial applications. However, limited information is available regarding its drought tolerance during the seedling stage. In this study, one-year-old seedlings were subjected to five treatments based on soil relative water content (RWC): moderate drought (T1, 40 ± 5%), severe drought (T2, 20 ± 5%), control (CK, 70 ± 5%), and rewatering following moderate (T3) and severe drought stress (T4), with RWC restored to 70 ± 5%. Under drought stress, seedlings exhibited adaptive responses including reduced growth, enhanced antioxidant enzyme activity, osmotic regulation, and changes in endogenous hormone levels. Seedlings showed good tolerance and recovery under moderate drought, but severe drought caused substantial damage and limited post-rewatering recovery. Pearson correlation and principal component analyses revealed that betaine, APX, SA, IAA, ABA, chlorophyll (a + b) content, and crown growth were strongly associated with drought response and could serve as key indicators for drought resistance assessment in I. polycarpa. These findings provide insights into the physiological mechanisms of drought adaptation and support the development of a reliable evaluation system for drought tolerance in this promising species. Full article

Malania oleifera Chun & S.K. Lee, an endemic monotypic species that belongs to the family Olacaceae, is under continuous pressure of decline owing to several ecological and physiological factors. The present study aimed to establish an efficient in vitro protocol for callus-mediated indirect somatic embryogenesis in M. oleifera by alleviating tissue browning. Internodes and leaves obtained from seedlings were used as explants. Antioxidant pre-treatment (ascorbic acid, AA) followed by different carbon sources (sucrose, maltose, glucose, and fructose) and plant growth regulators in various concentrations and combinations were employed in Woody Plant Medium (WPM) to alleviate explant browning and induce callus formation from the explants. AA pre-treatment and subsequent culture on maltose at a concentration of 116.8 mM were optimal for controlling phenolic exudation on >90% of both explants. The highest responses of 53.77% and 57.43% for embryogenic calli were induced from internode and leaf explants, respectively. The highest responses, 85.22% and 93.80%, were observed for somatic embryos that matured into the globular, heart-shaped and torpedo stages at different percentages on NAA 2.5 mg/L in combination with BA 1.0 mg/L for both explants. The matured somatic embryos were finally germinated at a maximum concentration of GA₃, 2.0 mg/L. All plantlets were successfully hardened and acclimatized under culture room conditions and then transferred to the greenhouse. The current study suggests an efficient protocol for indirect somatic embryogenesis by alleviating phenolic exudation from the explants of M. oleifera. This first successful report of in vitro culture establishment in M. oleifera may offer an effective alternative measure to conserve this species and provide a system for analyzing bioactive chemicals and for use in the oil industry. Full article

Magnetic field (MF) priming provides a chemical-free alternative to conventional methods; however, static exposure approaches are often limited by spatial heterogeneity in field–seed interaction caused by fixed seed positioning, undermining both treatment uniformity and reproducibility. To address this, the present study investigated the effects of dynamic MF exposure on the germination and early growth of Khao Dawk Mali 105 (KDML 105) rice seeds. A novel MF testing apparatus was developed using a 150 mT permanent magnet and a vortex-based air injection system designed to continuously rotate and redistribute seeds, ensuring uniform exposure. Seeds were treated for 0, 5, 10, 15, and 20 min to evaluate effects on vigor, germination, and seedling growth. The results showed that 5 and 10 min exposures significantly enhanced seed vigor (93.00% and 94.67%, respectively) compared to the control (83.33%), with 10 min yielding the highest improvement (p < 0.05, DMRT). Shoot and root growth also increased by 14.21% and 99.59%, respectively. These findings suggest that moderate-duration dynamic MF exposure is an efficient, eco-friendly priming technique for improving seed vigor and early growth. Future research should explore long-term agronomic impacts, economic feasibility, and varietal responses. The apparatus’s scalable design supports integration into industrial seed processing lines, advancing sustainable rice production. Full article

The large yellow croaker (Larimichthys crocea) is one of China’s most economically important marine fish species, with its cage culture production leading the nation for many years. However, the rapid expansion of aquaculture has brought challenges such as germplasm degradation, reduced disease resistance, inconsistent product quality, and low adoption of improved strains, which have hindered the sustainable development of the industry. The primary objective of this review is to summarize the current practices and challenges in seedling selection for L. crocea. The secondary objectives include discussing the influence of genetic, physiological, and environmental factors on growth performance and proposing future research directions for sustainable breeding programs. This review covers key topics including morphological screening, growth performance evaluation, genetic diversity conservation, disease resistance improvement, and adaptation to environmental stress. It also explores the application of modern technologies such as marker-assisted selection, intelligent monitoring, environmental control, precision feeding, and disease prevention. Moreover, it highlights core issues in current breeding practices, such as over-reliance on single-trait selection and insufficient integration of environmental adaptability and disease resistance. Finally, future trends are discussed, emphasizing the integration of genomic tools with artificial intelligence to promote intelligent, precise, and sustainable breeding approaches. These insights aim to enhance aquaculture productivity while supporting long-term ecological balance and industry sustainability. 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 objective of this study was to investigate the chemical composition of the obtained products, as well as the antioxidant activity and bio-stimulant potential of the liquid fractions. The biomass was subjected to pyrolysis in a pilot-scale reactor, followed by distillation of the pyroligneous liquid to separate volatile compounds and enrich bioactive fractions. The samples were analysed by FTIR, TGA/DTG, and GC-MS. Antioxidant activities were assessed through DPPH, FRAP, and total phenolic content assays, while the bio-stimulant potential was evaluated through germination and growth tests of lettuce and arugula seeds. The results showed that the distilled fraction had lower acidity, greater chemical stability, and high antioxidant activity, with the presence of industrially valuable compounds such as methoxylated phenols and furfural. Furthermore, application of the distilled liquid at 0.1% concentration stimulated early seedling development—especially in arugula—while higher concentrations demonstrated inhibitory effects. These findings show that distillation of pyroligneous liquid is an effective strategy to enhance its bioactive properties, enabling its use as a natural antioxidant and plant bio-stimulant. Full article

Polyembryonic maize, capable of producing multiple seedlings from a single kernel, holds great potential value in agricultural and industrial applications, but the seedling quality needs to be improved. In this study, seedlings of two waxy maize (Zea mays L. sinensis Kulesh) inbred lines, D35 (a polyembryonic line with twin shoots) and N6110 (single-shoot), exhibited similar relative growth rates during 1 to 5 days post-germination. UPLC-MS/MS profiling of 3- to 5-day-old seedling roots and shoots revealed that H2JA, MeSAG, and IAA-Val-Me were the common differentially accumulated metabolites (DAMs) of the 3-day-old vs. 5-day-old seedlings of D35 and N6110 in the same tissues, and MeSAG, tZ9G, cZROG, and DHZROG were identified in D35 vs. N6110 across the same tissues and the same periods. RNA-seq analyses showed various processes involved in seedling development, including DNA replication initiation, rhythmic processes, the cell cycle, secondary metabolic processes, and hormone biosynthetic regulation. The differentially expressed genes (DEGs) between D35 and N6110 were significantly enriched in organic hydroxy compound biosynthetic, alcohol biosynthetic, organic hydroxy compound metabolic, abscisic acid biosynthetic, and apocarotenoid biosynthetic processes. The KEGG-enriched pathways of DAMs and DEGs identified that AUX1, AHP, A-ARR, JAR1, SIMKK, ERF1, and GID2 might be conserved genes regulating seedling growth. The integrated analyses revealed that 98 TFs were potentially associated with multiple hormones, and 24 of them were identified to be core genes, including 11 AP2/ERFs, 4 Dofs, 2 bZIPs, 2 MADS-box genes, 2 MYBs, 1 GATA, 1 LOB, and 1 RWP-RK member. This study promotes a valuable understanding of the complex hormone interactions governing twin-shoot seedling growth and offers potential targets for improving crop establishment via seedling quality. Full article

Sweet potato (Ipomoea batatas (L.) Lam.), as an important crop, is rich in polyphenols, vitamins, minerals, and other nutrients in its roots and leaves and is gradually gaining popularity. The use of endophytic bacteria to improve the quality of sweet potato can protect the environment and effectively promote the sustainable development of the sweet potato industry. In this study, 12 strains of endophytic bacteria were isolated from sweet potato. Through nitrogen fixation, phosphorus solubilization, indoleacetic acid production, siderophore production, ACC deaminase production, and carboxymethyl cellulose production, three strains with multiple biological activities were screened out. Among them, MEPW12 had the most plant growth-promoting functions. In addition, MEPW12 promoted host chlorophyll accumulation and inhibited pathogen growth and colonization in sweet potato roots and can utilize various carbon sources and salts for growth. It can also grow in extreme environments of high salt and weak acid. MEPW12 was identified as Bacillus amyloliquefaciens with a genome size of 3,928,046 bp and a GC content of 46.59%. After the annotation of multiple databases, it was found that MEPW12 had multiple enzymatic activities and metabolic potential. Comparative genomics and pan-genomics analyses revealed that other Bacillus sp. strains of MEPW12 have similar functions. However, due to adaptation to different growth environments, there are still genomic differences and changes. Inoculation with MEPW12 induced the high expression of IbGH3.10, IbERF1, and other genes, thereby promoting the growth of sweet potatoes. Bacillus amyloliquefaciens strain MEPW12 is a sweet potato endophyte with multiple growth-promoting functions, which can promote the growth of sweet potato seedlings. This study provides new microbial resources for developing microbial agents and improving the quality of sweet potatoes. Full article

Madhuca longifolia (M. longifolia), a tropical tree valued for its medicinal, nutritional, and industrial applications, exhibits severe sensitivity to low-temperature stress in subtropical regions, particularly during seedling establishment. To address this challenge, this study systematically identified 109 NAC genes in M. longifolia and characterized their functional roles in cold adaptation via multi-omics analyses. All NAC proteins were hydrophilic. Key members (e.g., MlNAC026, MlNAC077, MlNAC076) were localized in the nucleus. Phylogenetic analysis grouped them with ANAC072 (RD26), a homolog involved in leaf senescence and ABA-regulated cold stress responses. The NAC family expanded primarily through segmental duplication. And low Ka/Ks ratios (<1) indicated purifying selection. Promoter analysis highlighted the prevalence of dehydration-responsive DRE and LTR cis-acting elements. Transcriptomic profiling under cold stress identified five continuous differentially expressed genes (MlNAC026, MlNAC040, MlNAC059, MlNAC077, and MlNAC078) linked to regulatory functions. Homology modeling predicted 3D structures of cold-responsive NAC proteins, and STRING network analysis indicated independent regulatory mechanisms due to the absence of prominent interaction nodes. These findings advance our understanding of NAC-mediated cold tolerance and offer genetic targets to enhance M. longifolia resilience in subtropical climates. 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