Search Results (42)

Banana fruits are harvested and then undergo rapid ripening and senescence, sharply limiting their shelf-life and marketability. Myo-inositol (MI) is an important regulator in ethylene production and reactive oxygen species (ROS) accumulation; however, its involvement in the postharvest ripening process of banana remains to be determined. This study found that postharvest application of MI could efficiently delay the fruit ripening and extend the time in which the luster, color, and hardness were maintained in two cultivars with contrasting storage characteristics, storable ‘Brazil’ and unstorable ‘Fenza No. 1’, when stored at room temperature (23 °C ± 2 °C). Moreover, physiological, metabolic, and gene expression analyses indicated that MI application improved MI metabolism and postponed ethylene biosynthesis and cell wall loosening. The decrease in ethylene production was associated with a reduction in the expression of ACS1 and ACO1 genes. MI treatment decreased the expressions of PL1/2, PG, and EXP1/7/8, which may account for the delay in softening. In addition, the application of MI could alleviate ROS-mediated senescence and cell membrane damage by promoting the activities of SOD, POD, and anti-O₂⁻ and decreasing PPO activity. This study shed light on the function of MI in regulating the postharvest ripening and senescence of bananas and provided an efficient strategy for extending shelf-life and reduce losses. Full article

Soybeans are a major global commodity. A major challenge in soybean production is premature bean cracking, which leads to seed shedding and crop loss. Consistent breeding efforts are being made to minimize seed shedding in soybeans worldwide. Soybean breeding for increased abdominal suture strength has not resulted in varieties that are guaranteed to be resistant to premature cracking. Therefore, for further study of the issue, the study of the structural features of the soybean hilum is of practical interest. The trait of fusion of the seed hilum with the pod safe seeds from shedding. The paper presents studies of a soybean collection based on cracking features and resistance to seeds shedding. The largest number of cracking forms were found in the varieties of the first four maturity groups (000, 00, 0 and I). A positive correlation was observed between the cracking and non-shedding seeds traits (r = 0.48). The trait of fusion of the seed hilum with the pod valves turned out to be dominant. Our findings suggest that this trait may be influenced by a single gene or exhibit intermediate inheritance, but further genetic analysis is needed. The average yields of the control nursery numbers with a fused seed stalk (4.36 t/ha) are lower than the average yields of numbers without this trait (4.75 t/ha). Full article

The soybean yield per unit area in Xinjiang has reached a high level, with the crop maturing quickly because of the higher temperatures and levels of mechanization. However, environmental factors cause flowers and pods to shed easily, limiting yield potential. Efficient plant growth regulators (PGRs) used to increase crop yields have gained popularity, but their effectiveness in reducing flower and pod shedding, considering factors such as environment, crop variety, and time of spraying, remains unclear. This study investigated whether spraying several PGRs could reduce soybean flower and pod shedding. Field experiments were conducted from 2022 to 2024 in Ili, Xinjiang, China, using α-naphthaleneacetic acid (NAA), prohexadione-calcium (Pro-Ca), and iron chlorine e6 (ICE6) with foliar applications of 300, 450, and 45 g ha⁻¹ at the four-node stage (V4) and full pod stage (R4). All PGR treatments reduced flower and pod shedding over the years and resulted in an increase in the average flower and pod numbers compared to normal-growth-treated (CK) soybeans. The effective slowing of flower and pod shedding during the critical pod formation stage (R4) ensured a stable yield potential. The flower-to-pod conversion rate was higher after spraying plants with PGRs than for the CK group, and pod retention was higher at the beginning of maturity (R7). Our results demonstrated that spraying PGRs (NAA, Pro-Ca, and ICE6) effectively reduced soybean flower and pod shedding, optimized pod distribution, and increased soybean yield potential. The study findings provide a useful reference for global soybean growers to optimize planting methods. Full article

The wind and slope are deemed to be the determinant factors driving the extreme or erratic spread behavior of wildfire, which, however, has not been fully investigated, especially to elaborate the mechanism of fire spread associated with heat transfer and fluid dynamics. A systematic study is therefore carried out based on a physical-based simulation and proper orthogonal decomposition (POD) analysis. Results show that compared to the wind, the slope plays a more profound effect on the fire structure; with the increase in slope, the fire line undergoes a transition from a W-shape to the U- and pointed V-shape, accompanied by stripe burning zones, indicating a faster spread but incomplete combustion. The wind effect is distinguished by mainly inducing a turbulent backflow ahead of the fire front, while the slope effect promotes convective heating via the enhanced slant fire plume. Different mechanisms are also identified for the heat transfer ahead of the fire line, i.e., the radiative heat is affected by the combined effects of the flame length and view angle, and in contrast, the convective part of the heating flux is dominated by the action of the flame attachment, which is demonstrated to play a crucial role for the fire spread acceleration at higher slopes (>20°). The POD analysis shows the distinct pattern of flame pulsating for the respective wind and slope effects, which sheds light on modeling the unsteady features of fire spreading and reconfirms the necessity of considering the different effects of these two environmental factors. Full article

Bioinputs are natural products applied to crops that contribute to more sustainable agriculture by boosting yields and reducing environmental impacts. In Brazil, the use of bioinputs such as Bradyrhizobium in soybean has been consolidated, but the expansion of on-farm bioinput production is currently initiating a new revolution. Furthermore, applications of bioinputs to cash crops in Brazil have shed light on the great potential of such growth-promoting microorganisms (GMPs) to improve nutrient uptake and increase productivity. This study explores the effect of the complementary inoculation with growth-promoting bacteria of post-emergence soybean, previously inoculated with Bradyrhizobium spp. Five treatments with growth-promoting bacteria were evaluated: T1—Control (no inoculation); T2—Azospirillum brasilense; T3—Pseudomonas fluorescens and Azospirillum brasilense; T4—Priestia aryabhattai, Bacillus haynesii, and Bacillus circulans; and T5—Priestia megaterium and Bacillus subtilis. In comparison with the control, all treatments with growth-promoting bacteria of the genera Azospirillum, Pseudomonas, Priestia, and Bacillus, applied after soybean emergence, induced 4–7% higher grain yields. Co-inoculation with Priestia megaterium and Bacillus subtilis (treatment T5) resulted in a higher 1000-grain weight, while Priestia aryabhattai, Bacillus haynesii, and Bacillus circulans (treatment T4) increased the number of pods and shoot dry weight. Our conclusion is that bioinputs increase soybean productivity and make agriculture more sustainable and efficient. Full article

Agropyron mongolicum Keng is a diploid perennial grass of triticeae in gramineae. It has strong drought resistance and developed roots that can effectively fix the soil and prevent soil erosion. GDSL lipase or esterases/lipase has a variety of functions, mainly focusing on plant abiotic stress response. In this study, a GDSL gene from A. mongolicum, designated as AmGDSL1, was successfully cloned and isolated. The subcellular localization of the AmGDSL1 gene (pCAMBIA1302-AmGDSL1-EGFP) results showed that the AmGDSL1 protein of A. mongolicum was only localized in the cytoplasm. When transferred into tobacco (Nicotiana benthamiana), the heterologous expression of AmGDSL1 led to enhanced drought tolerance. Under drought stress, AmGDSL1 overexpressing plants showed fewer wilting leaves, longer roots, and larger root surface area. These overexpression lines possessed higher superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and proline (PRO) activities. At the same time, the malondialdehyde (MDA) content was lower than that in wild-type (WT) tobacco. These findings shed light on the molecular mechanisms involved in the GDSL gene’s role in drought resistance, contributing to the discovery and utilization of drought-resistant genes in A. mongolicum for enhancing crop drought resistance. Full article

This study delves into the valorization of pea pod waste using hydrothermal processes, focusing on optimizing key parameters such as temperature, biomass-to-water ratio, particle size, and catalyst influence. Noteworthy findings include the significant impact of temperature variations on product yields, with 180 °C favoring sugars, HMF, and furfural, while 220 °C and 260 °C lead to distinct platform chemical productions. The utilization of a 1:20 biomass-to-water ratio consistently enhances yields by 10%, underscoring its importance in promoting efficient hydrolysis without excessive product degradation. Furthermore, the investigation into particle size reveals that smaller dimensions, particularly 1 mm particles, improved heat and mass transfer, reduced diffusion barriers, and enhanced digestibility, ultimately boosting overall efficiency in platform chemical production. Moreover, the study sheds light on the role of catalysts in the hydrothermal processes, showcasing the differential impact of acid and basic catalysts on product yields. Acid catalysts demonstrate a notable increase of up to 135.5% in the production of platform chemicals, emphasizing their crucial role in enhancing reaction efficiency. The complex relationship between agitation, temperature, and product formation is elucidated, with experiments revealing varying outcomes based on the presence or absence of agitation at different temperatures. These findings provide valuable insights into optimizing pea pod waste valorization, offering a pathway towards sustainable and efficient conversion of agricultural residues into valuable platform chemicals. Full article

This study aims to investigate the wake of two tandem square cylinders based on the Proper Orthogonal Decomposition (POD) analyses of the PIV and hotwire data. The cylinder centre-to-centre spacing ratio L/w examined is from 1.2 to 4.2, covering the four flow regimes, i.e., extended body, reattachment, transition and co-shedding. The Reynolds number examined was 1.3 × 10⁴. A novel Proper Orthogonal Decomposition (POD) technique (hereafter referred to as POD_HW) is developed to analyse data from single point hotwire measurements, offering a new perspective compared to the conventional POD analysis (POD_PIV) based on Particle Image Velocimetry (PIV) data. A key finding is the identification of two distinct states, reattachment and co-shedding, within the transition flow regime at L/w = 2.8, which POD_PIV fails to capture due to the limited duration of the PIV data obtained. This study confirms, for the first time, the existence of these states as proposed by Zhou et al. (2024), highlighting the advantage of using POD_HW for capturing intermittent flow phenomena. Furthermore, the analysis reveals how the predominant coherent structures contribute to the total fluctuating velocity energy in each individual regime. Other aspects of the flow are also discussed, including the Strouhal numbers, the contribution to the total fluctuating energy of the flow from the first four POD modes, and a comparison between different regimes. Full article

Arundo donax is widely used as an ornamental plant in landscape gardening because of its adaptability to varying degrees of waterlogged conditions. However, to date, little information is available about the adaptive mechanism of A. donax under waterlogging stress. The results showed that long-term mild waterlogging efficiently induced the formation of adventitious roots (ARs) and further promoted root aerenchyma development, and that the activity of antioxidant enzymes (SOD, POD, and CAT) in Ars also was greatly enhanced after waterlogging. At the transcriptomic level, the expression of genes related to apoptosis, the regulation of cell division, ethylene biosynthesis, alginate synthesis, auxin signaling pathways, and anaerobic respiration was mostly up-regulated after the occurrence of waterlogging stress but genes involved in the abscisic acid signaling pathways were partly down-regulated, which indicated a preferential and favorable transcriptional response in regulating adventitious root development. Taken together, this study definitely advances our knowledge of the morphological, physiological, and transcriptomic responses of A. donax under waterlogging stress and sheds new lights on its adaptive mechanisms. Full article

Drought at the flower and pod stage, which is the most moisture-sensitive stage of soybean development, is the main cause of yield loss in soybean. Nitrogen is a vital nutrient for soybeans. The objective of this study was to assess the potential of post-drought nitrogen fertilization at the soybean (Heihe 45) pod stage to (1) reduce pod shedding and increase yield, and (2) elucidate the mechanisms by which nitrogen fertilization regulates soybean growth under drought stress. The pot experiment was designed with two moisture levels and three nitrogen levels, resulting in a total of six treatments. The results show that nitrogen reduces cellular oxidation by regulating key enzymes of sucrose metabolism, such as sucrose synthase and sucrose phosphate synthase; and regulates cellulase to reduce shedding and mitigate drought. Comparison of low and high nitrogen conditions under drought conditions showed that the number of flowers and pods in soybean increased by 30% and 32.94%, respectively, malondialdehyde content decreased by 24%, cellulase activity in flowers and pods decreased by 15.07% and 12.31%, respectively, and yields increased by 29.98% under high nitrogen conditions. The high nitrogen treatment performed optimally and the differences between treatments reached the significant level. Full article

The flow around two tandem circular cylinders in proximity to a wall is investigated using particle image velocimetry (PIV) for Re = 2 × 10³. The spacing ratios L/D are 1, 2, and 5, and the gap ratios G/D are 0.3, 0.6, and 1. The proper orthogonal decomposition (POD) method and λci vortex identification method are used to investigate the evolution of flow structure, and the influences of L/D and G/D on flow physics are shown. At L/D = 2 and G/D = 0.3, a “pairing” process occurs between the wall shear layer and the upstream cylinder’s lower shear layer, resulting in a small separation bubble behind the upstream cylinder. At L/D = 1, the Strouhal number (St) increases with decreasing G/D. At three gap ratios, the St gradually decreases as L/D increases. At G/D = 0.3, there is nearly a 49.98% decrease from St = 0.3295 at L/D = 1 to St = 0.1648 at L/D = 5, which is larger than the reductions in cases of G/D = 0.6 and G/D = 1. The effects of L/D on the evolution of flow structure at G/D = 0.6 are revealed in detail. At L/D = 1, the vortex shedding resembles that of the single cylinder. As L/D increases to 2, a squarish flow structure is formed between two cylinders, and a small secondary vortex is formed due to induction of the lower shear layer of the upstream cylinder. At L/D = 5, there is a vortex merging process between the upper wake vortices of the upstream and downstream cylinders, and the lower wake vortex of the upstream cylinder directly impinges the downstream cylinder. In addition, the shear layers and wake vortices of the upstream cylinder interact with the wake of the downstream cylinder as L/D increases, resulting in reductions in velocity fluctuations, and the production and turbulent diffusion of turbulent kinetic energy are decreased behind the downstream cylinder. Full article

This study focuses on optimizing the mutagenesis process for Morchella eximia (Mel-7) mycelia through atmospheric and room temperature plasma (ARTP) mutation and explores the resultant thermal adaptability and physiological responses of mutant strains. This research demonstrated a clear relationship between ARTP mutagenesis exposure duration and lethality rate, indicating that an exposure time of 40 s resulted in the optimal balance of inducing mutations without causing excessive mortality. Additionally, this study established 43 °C as the ideal screening temperature for identifying mutant strains with enhanced heat resistance, as this temperature significantly challenges the mycelia while allowing thermotolerant strains to be distinguishable. Among the screened mutants, strains L21, L23, L44, and L47 exhibited superior growth and high-temperature tolerance, with notable resilience at 30 °C, highlighting their enhanced adaptability to above-optimal temperatures. Furthermore, this research delved into biochemical responses, including lipid peroxidation and non-enzymatic antioxidant content, highlighting the diverse mechanisms, such as enhanced lipid peroxidation resistance and increased antioxidant content, employed by mutant strains to adapt to temperature fluctuations. The activities of antioxidant enzymes, including peroxidase (POD) and superoxide dismutase (SOD), were shown to be significantly influenced by temperature elevations, illustrating their critical roles in the thermal adaptation of mutant strains. These findings shed light on the importance of considering mutation duration and temperature screening in the development of thermotolerant fungal strains with potential applications in various industries. This study’s breakthrough lies in its comprehensive understanding of the thermal adaptability of Mel-7 mycelia and the identification of promising mutant strains, offering valuable insights for both academic and industrial purposes. Full article

The impact of particle addition jets on the flow field in natural gas pipelines was investigated, and the structural information of the flow field at different flow velocities in a symmetric jet flow was analyzed via numerical simulation. The results of coherent structures in the high-pressure natural gas pipeline reveal vortex structures of varying sizes both upstream and downstream of the jet flow. To determine the spatial distribution of the main vortex structures in the flow field, proper orthogonal decomposition (POD) mode analysis was performed on the unsteady numerical results. Moreover, the detailed spatial characteristics of the coherent vortex structures represented by each mode were obtained. The results indicate that the large-scale vortex structures within the pipeline are balanced and stable, with their energy increasing as the jet flow velocity increases. Additionally, higher-order modes exhibit significant shedding of small-scale vortex structures downstream of the jet flow. In this research, coherent structures present in symmetric particle addition jets are provided, offering theoretical support for future investigations on the distribution of particle image velocimetry (PIV) flowmeters. Full article

This study aims to address the current situation of the late start of mechanized harvesting technology for the pod pepper, the high damage rate of existing pod pepper harvesters, and the lack of theoretical support for key harvesting components. The Hertz theory is employed to investigate the damage mechanism of collisions between pod pepper and comb fingers. The study analyzes the maximum deformation of pod pepper and the critical speed at which damage occurs during the collision process. Furthermore, it explores the critical relative speed that leads to damage in pod pepper. Orthogonal tests are conducted to analyze the effects of rotational speed, hose thickness, and moisture content on the efficiency of pod pepper picking. The experimental results are then subjected to multifactorial ANOVA to identify the optimal test parameters. The structural and motion parameters of the picking device are optimized based on these conditions. It is determined that the critical relative velocity for damage to pod pepper during a collision with the comb finger is V₀ = 11.487 m s⁻¹. The collision velocities of pod pepper with different hose thicknesses are analyzed using the i-SPEED TR endoscopic high-speed dynamic analysis system to obtain the corresponding collision velocities for different hose thicknesses. The study finds that rotational speed, hose thickness, and the water content of pod pepper affect the damage rate and stem shedding rate. The optimal experimental parameters are determined to be a rotational speed of 705.04 rpm, hose thickness of 3 mm, and water content of the pepper of 71.27%. Full article

Predicting the flow situation of cavitation owing to its high-dimensional nonlinearity has posed great challenges. To address these challenges, this study presents a novel reduced order modeling (ROM) method to accurately analyze and predict cavitation flow fields under different conditions. The proposed ROM decomposes the flow field into linearized low-order modes while maintaining its accuracy and effectively reducing its dimensionality. Specifically, this study focuses on predicting cavitation on the Clark-Y hydrofoil using a combination of numerical simulation, proper orthogonal decomposition (POD), and neural networks. By analyzing different cavitation conditions, the results revealed that the POD method effectively reduces the order of the cavity flow field while achieving excellent flow field reconstruction. Notably, the zeroth- and first-order modes are associated with attachment cavitation, while the second-, third- and fourth-order modes correspond to cavitation shedding. Additionally, the fifth- and sixth-order modes along the hydrofoil surface are associated with the backward jet flow. To predict the conditions of high-energy modes, the neural network proved to be more effective, exhibiting excellent performance in stable attached cavitation. However, for cloud cavitation, the accuracy of the neural network model requires further improvement. This study not only introduces a novel approach for predicting cavitation flow fields but also highlights new challenges that will require continuous attention in future research endeavors. Full article