Search Results (2,411)

Leaf senescence is a precisely regulated developmental process that is critical for grapevine growth and yield, which is easily influenced by environmental factors. High temperature is a major factor that accelerates senescence rapidly, adversely affects photosynthetic performance, severely hindering fruit nutrient metabolism and growth. This study investigated chlorophyll fluorescence and physiological traits in grape (Vitis vinifera L.) leaves at different senescence stages under natural high-temperature conditions in Turpan. Measurements included chlorophyll content, MDA levels, antioxidant enzyme activities, and chlorophyll fluorescence parameters. The results showed that (1) young leaves exhibited higher and more sustained chlorophyll content but were prone to wilting, whereas older leaves showed accelerated chlorosis and functional decline; (2) high temperature severely impaired PSII function, inhibiting electron transport and photochemical efficiency, reflected in increased ABS/RC, TR_o/RCC, and DI_o/RC, and decreased F_v/F_m, F_v/F_o, and PI_abs; (3) POD, SOD, CAT and MDA levels initially increased then decreased, correlating with photosynthetic changes and leaf age; and (4) young leaves maintained stronger photosynthetic capability and physiological resilience than older ones. Although partial recovery occurred after temperature reduction, photosynthetic and antioxidant activities did not fully revert. This suggests persistent heat-induced functional decline and accelerated senescence, providing insights for understanding heat-induced leaf senescence and developing strategies for cultivating grapevines. Full article

High temperatures are one of the most important abiotic stressors affecting the survival and growth of American shad (Alosa sapidissima). Building on previous omics sequencing studies of A. sapidissima liver and gills under high temperature stress, this study focused on investigating the regulatory role of miR-1236-3p and its target gene hsp90b1. The results indicate that the full-length cDNA of the hsp90b1 gene is 2023 bp and comprises a 5’ end of 58 bp, a 3’ end of 84 bp, and a coding region of 1881 bp, encoding 626 amino acids. Sequence alignment and phylogenetic tree analysis reveal that the hsp90b1 sequence is highly conserved across species. In situ hybridization showed that hsp90b1 is mainly localized in the cytoplasm. Software prediction identified a potential binding site between miR-1236-3p and hsp90b1. Through the construction of wild-type and mutant 3’UTR hsp90b1 dual luciferase reporter plasmids, the targeted relationship between the two was confirmed. In addition, the spatiotemporal expression levels of the hsp90b1 was found to be highest in the multicellular stage and liver tissue at a cultivation temperature of 27 °C; miR-1236-3P was highly expressed in the hatching stage and heart tissue at 30 °C. These findings provide a theoretical foundation for further investigating the regulatory role of non-coding RNA in A. sapidissima heat stress and offer data for subsequent molecular breeding studies. Full article

In Northeast Brazil, climatic factors and technology synergistically enhance melon productivity and fruit quality. However, the region requires further research on the efficient use of water resources, particularly in determining the crop coefficient (Kc), which comprises the evaporation coefficient (Ke) and the transpiration coefficient (Kcb). Air temperature affects crop growth and development, altering the spectral response and the Kcb. However, the direct influence of air temperature on Kcb and spectral response remains underemphasized. This study employed unmanned aerial vehicle (UAV) with RGB and Red-Green-NIR sensors imagery to extract biophysical parameters for improved water management in melon cultivation in semiarid northern Bahia. Field experiments were conducted during two distinct periods: warm (October–December 2019) and cool (June–August 2020). The ‘Gladial’ and ‘Cantaloupe’ cultivars exhibited higher Kcb values during the warm season (2.753–3.450 and 3.087–3.856, respectively) and lower during the cool season (0.815–0.993 and 1.118–1.317). NDVI-based estimates of Kcb showed strong correlations with field data (r > 0.80), confirming its predictive potential. The results demonstrate that UAV-derived NDVI enables reliable estimation of melon Kcb across seasons, supporting its application for evapotranspiration modeling and precision irrigation in the Brazilian semiarid context. Full article

There is increasing evidence on the occurrence of Crithidia spp. in patients presenting either cutaneous or visceral leishmaniasis, solely or associated with Leishmania. We analyzed growth, morphology, and temperature tolerance of two C. fasciculata strains, the reference strain COLPROT048 and patient isolate COLPROT606. We also evaluated their co-cultivation with L. braziliensis, macrophage infectivity, and infections in hamsters, BALB/c mice, and sandflies. In culture, both Crithidia strains survived at 32 °C for 96 h, showing major morphological alterations and decreased mitochondrial membrane potential, with ΔΨm reducing to 52% in COLPROT606. At 34 °C, the patient isolate showed an 80% reduction in cell number. Mixed cultivation of Crithidia-Leishmania led to recovery of only Crithidia. In macrophages, C. fasciculata alone was virtually eliminated, and in co-infection only Leishmania was detected. No Crithidia lesion or RNA were found in infected mice or hamsters, while L. braziliensis reached 1145–1625 parasites/mg of tissue. In sandflies, C. fasciculata successfully established infection for up to 7 days, both alone and in coinfections. Amphotericin B IC₅₀ values at 72 h were 4- to 5-fold higher in C. fasciculata strains compared to L. braziliensis. Our results indicate that both C. fasciculata strains are unable to reproduce the pathogenic effect in vitro and in vivo models. Full article

Lipids obtained from microalgae have recently received significant attention from the energy and food industries. Microalgae are promising alternatives and are more sustainable sources of lipids for the food industry, which faces a growing demand for food and increased environmental awareness among consumers. This study provides a bibliometric review of research articles published between 2019 and 2024 with the aim of understanding the future trends and tendencies of the applications of microalgal lipids in the food industry. A thorough assessment of 255 articles retrieved from the Scopus database showed an apparent decrease in the number of publications per year within the analyzed timeframe. The predominant focus has been basic research conducted on a lab-scale using chlorophytes (green algae) to optimize lipid production by modulating physicochemical cultivation parameters (i.e., nutrient availability, temperature, light, and pH). Lipids were mainly extracted using the Bligh and Dyer or Folch methods, quantified gravimetrically, and characterized using gas chromatography coupled to mass spectrometry. Publications referring to polyunsaturated fatty acids, such as omega-3 and omega-6, were the most abundant. The results emphasized the significance of microalgae as a promising biotechnological platform for the production of lipids within the food industry. Full article

Corn is one of the most widely cultivated cereal crops and is rich in antioxidant compounds, especially phenolics. However, many of these are bound to cell wall components, requiring pre-treatment for release. Solid-state fermentation (SSF) with Rhizopus oryzae has been used to enhance antioxidant capacity in grains and legumes, though its application in pigmented corn (PC) has not been reported. This study evaluated R. oryzae growth on PC via SSF and its effect on phenolic compound release and antioxidant capacity (AC). Variables such as temperature, pH, inoculum, and medium salts were tested for their influence on phenolic release and AC. Nutrient changes in PC due to SSF were also examined. HPLC-MS was used to analyze the phenolic compounds’ profile. R. oryzae grew effectively on PC, increasing total phenolic content (TPC) and AC by 131 and 50%, respectively. The pH was found to negatively impact phenolic release. The SSF also raised protein content by 10% and reduced carbohydrates and fiber by 3 and 8%. Thirteen phenolic compounds were identified, including Feruloyl tartaric acid ester and p-Coumaroyl tartaric acid glycosidic ester, with known anti-inflammatory properties. This process offers a sustainable method for enhancing the functional properties of pigmented corn. Full article

Mychonastes homosphaera MHSC24 is a green microalga newly isolated from a brackish coastal site in Korea. This study represents the first indigenous record of this species in the country. It provides a comprehensive characterization of its morphological, molecular, physiological, and biochemical characteristics. This microalga was identified through morphological observations and multilocus phylogenetic analyses. Strain MHSC24 exhibited robust growth under mesophilic temperatures (15–27 °C), moderate light intensities (88–300 μmol photons m⁻² s⁻¹), and low salinity levels (0–10 PSU). Optimal growth was observed at 27 °C, 193 μmol photons m⁻² s⁻¹, and 0 PSU. Under standard cultivation, the strain exhibited high protein levels (~54% of dry weight, DW) and accumulated substantial amounts of canthaxanthin (5.59 mg g⁻¹ DW), the predominant carotenoid in its pigment profile. Thus, MHSC24 is a promising candidate for sustainable protein- and carotenoid-based applications. Palmitic acid (11.95 mg g⁻¹ DW) and galactose (2.07 mg g⁻¹ DW) were the predominant fatty acid and monosaccharide, respectively. The physiological resilience, high protein yield, and substantial canthaxanthin accumulation of MHSC24 support its potential utilization in the functional food, feed, and nutraceutical sectors. Therefore, this study provides a basis for optimized cultivation strategies and industrial exploitation of indigenous Korean microalgae. Full article

Sphagneticola trilobata (L.) Pruski has been introduced to many countries due to its ornamental and economic value. However, it has been listed in the world’s 100 worst alien invasive species due to its invasive nature. This species easily escapes cultivation and forms dense ground covers. It reproduces asexually through ramet formation from stem fragments. It also produces a large number of viable seeds that establish extensive seed banks. The movement of stem fragments and the dispersal of seeds, coupled with human activity, contribute to its short- and long-distance distribution. S. trilobata grows rapidly due to its high nutrient absorption and photosynthetic abilities. It exhibits high genetic and epigenetic variation. It can adapt to the different habitats and tolerate various adverse environmental conditions, including cold and high temperatures, low and high light irradiation, low nutrient levels, waterlogging, drought, salinity and global warming. S. trilobata has powerful defense systems against herbivory and pathogen infection. These systems activate the jasmonic acid signaling pathway, producing several defensive compounds. This species may also acquire more resources through allelopathy, which suppresses the germination and growth of neighboring plants. These life history traits and defensive abilities likely contribute to its invasive nature. This is the first review to focus on the mechanisms of its invasiveness in terms of growth, and reproduction, as well as its ability to adapt to different environmental conditions and defend itself. Full article

Long-term greenhouse operations face a critical challenge in the form of soil quality degradation, yet the key intervention periods and underlying mechanisms of this process remain unclear. This study aims to quantify the effects of greenhouse lifespan on the evolution of soil quality and to identify critical periods for intervention. We conducted a systematic survey of greenhouse operations in a representative area of Yunnan Province, Southwest China, and adopted a space-for-time substitution design. Using open-field cultivation (OF) as the control, we sampled and analyzed soils from vegetable greenhouses with greenhouse lifespans of 2 years (G2), 5 years (G5), and 10 years (G10). The results showed that early-stage greenhouse operation (G2) significantly increased soil temperature (ST) by 8.38–19.93% and soil porosity (SP) by 16.21–56.26%, promoted nutrient accumulation and enhanced aggregate stability compared to OF. However, as the greenhouse lifespan increased, the soil aggregates gradually disintegrated, particle-size distribution shifted toward finer clay fractions, and pH changed from neutral to slightly alkaline, exacerbating nutrient imbalances. Compared with G2, G10 exhibited reductions in mean weight diameter (MWD) and soil organic matter (SOM) of 2.41–5.93% and 24.78–30.93%, respectively. Among greenhouses with different lifespans, G2 had the highest soil quality index (SQI), which declined significantly with extended operation; at depths of 0–20 cm and 20–40 cm, the SQI of G10 was 32.59% and 38.97% lower than that of G2, respectively (p < 0.05). Structural equation modeling (SEM) and random forest analysis indicated that the improvement in SQI during the early stage of greenhouse use was primarily attributed to the optimization of soil hydrothermal characteristics and pore structure. Notably, the 2–5 years was the critical stage of rapid decline in SQI, during which intensive water and fertilizer inputs reduced the explanatory power of soil nutrients for SQI. Under long-term continuous cropping, the reduction in MWD and SOM was the main reason for the decline in SQI. This study contributes to targeted soil management during the critical period for sustainable production of protected vegetables in southern China. Full article

Accurate land use/land cover (LULC) maps generated through cloud computing can support large-scale land management. Leveraging the rich resources of Google Earth Engine (GEE) is essential for developing historical maps that facilitate the analysis of regional LULC dynamics. We implemented the best-performing scheme on GEE to produce 30 m LULC maps for the Shandong Peninsula urban agglomeration (SPUA) and to detect LULC changes, while closely observing the spatio-temporal trends of landscape patterns during 2004–2024 using the Shannon Diversity Index, Patch Density, and other metrics. The results indicate that (a) Gradient Tree Boost (GTB) marginally outperformed Random Forest (RF) under identical feature combinations, with overall accuracies consistently exceeding 90.30%; (b) integrating topographic features, remote sensing indices, spectral bands, land surface temperature, and nighttime light data into the GTB classifier yielded the highest accuracy (OA = 93.68%, Kappa = 0.92); (c) over the 20-year period, cultivated land experienced the most substantial reduction (11,128.09 km²), accompanied by impressive growth in built-up land (9677.21 km²); and (d) landscape patterns in central and eastern SPUA changed most noticeably, with diversity, fragmentation, and complexity increasing, and connectivity decreasing. These results underscore the strong potential of GEE for LULC mapping at the urban agglomeration scale, providing a robust basis for long-term dynamic process analysis. Full article

Biodegradable mulch films (BDMs) have emerged as a promising alternative to conventional polyethylene (PE) films in modern horticulture, yet the effect of film thickness on crop performance remains inadequately understood. In this study, a two-year field experiment (2023–2024) under protected cultivation was conducted to evaluate BDMs with thicknesses (0.006, 0.008, and 0.010 mm) for watermelon production in Beijing, China. The results showed that all BDMs enhanced soil temperature and moisture compared to bare soil (main effect of mulching, p < 0.05) and significantly influenced soil available nitrogen (p < 0.05), while other soil properties were less affected. Year effects were generally not significant, reflecting the stable microclimatic conditions under hoop-house cultivation. Mechanical property assessments indicated substantial declines in tensile load, tensile strength, and elongation at break after field use, especially for thinner films. Notably, Bio-0.006 and Bio-0.008 significantly improved fruit weight and soluble sugar content relative to PE (p < 0.05), leading to higher yields and better commercial quality. These results suggested that appropriately thin BDMs can satisfy agronomic requirements for watermelon under protected cultivation while minimizing plastic residues, offering a practical basis for optimizing biodegradable film thickness to balance mulching performance, productivity, and environmental sustainability. Full article

Cordyceps militaris (C. militaris) is a medicinal fungus renowned for its diverse therapeutic properties, largely attributed to bioactive compounds such as cordycepin, polysaccharides, adenosine, D-mannitol, carotenoids, and ergosterol. However, the production and composition of these metabolites are highly influenced by cultivation conditions, highlighting the need for systematic optimization strategies. This review synthesizes current findings on how nutritional factors—including carbon and nitrogen sources, their ratios, and trace elements—and environmental parameters such as oxygen availability, pH, temperature, and light regulate C. militaris metabolite biosynthesis. The impacts of solid-state fermentation (using grains, insects, and agro-industrial residues) and liquid state fermentation (submerged and surface cultures) are compared, with attention to their roles in mycelial growth, fruiting body formation, and secondary metabolite production. Special emphasis is placed on mixed grain–insect substrates and light regulation, which have emerged as promising methods to enhance cordycepin accumulation. Beyond summarizing advances, this review also identifies key knowledge gaps that must be addressed: (i) the incomplete understanding of metabolite regulatory networks, (ii) the absence of standardized cultivation protocols, and (iii) unresolved challenges in scale-up, including oxygen transfer, foam control, and downstream processing. We propose that future research should integrate multi-omics approaches with bioprocess engineering to overcome these limitations. Collectively, this review highlights both current progress and remaining challenges, providing a roadmap for advancing the sustainable, scalable, and application-driven production of bioactive compounds from C. militaris. Full article

In greenhouse and plant factory production, improper design of the ventilation system and increasing scales will lead to a stagnant airflow zone, which could inhibit plant growth and induce physiological disease, such as tipburn. To increase the airflow within the plant canopy, simplify the equipment complexity, and improve operation convenience, a cultivation system was designed to provide a constant airflow within the plant canopy by integrating ventilation ducts with cultivation tanks. A three-dimensional computational fluid dynamics (ANSYS Fluent 2021R2) model was developed and validated through simulating the airflow distribution within the plant canopy under different intake air velocities. According to the simulated results, an intake air velocity of 10 m s⁻¹ showed better airflow uniformity, and the proportion of the suitable zone reached the highest value of 83% at an intake air velocity of 20 m s⁻¹. To validate the practical effectiveness of cultivation, a cultivation experiment was conducted. Five different canopy air velocities were set at 0 (CK), 0.35 (T₁), 0.5 (T₂), 0.65 (T₃), and 0.8 (T₄) m s⁻¹, respectively. The results showed that the photosynthetic and transpiration rate, as well as the fresh and dry weights of lettuce plants (Lactuca sativa cv. ‘Tiberius’), increased by 17.8%, 21.7%, 29.6%, and 29.9%, respectively, under treatment T₄ compared to those under the control, while the canopy air temperature and relative humidity decreased by 1.3 °C and 3.2%, respectively. The above results indicate that the newly designed cultivation system can be considered an effective system for improving lettuce plant growth and its canopy environment. Full article

In karst regions (KRs), unique surface morphology and irrational human exploitation have led to increasingly prominent issues such as land fragmentation and rocky desertification. Understanding the spatiotemporal evolution of cultivated land (CL) in these areas is of great significance for supporting regional socioeconomic development, food security, and ecological sustainability. This study focuses on Guilin, combining GIS spatial analysis with methods including kernel density analysis, dynamic degree, spatial transfer matrix, and a Geodetector to examine the spatiotemporal distribution characteristics, evolution trends, and driving factors of land use based on five-phase of land use data from 2000 to 2020. The results show that: (1) over the past two decades, land use in Guilin has been dominated by CL and forest land, with CL exhibiting a spatial pattern of more in the east and south, and less in the west and north; (2) the CL transfer-out rate exceeded the transfer-in rate, mainly shifting to construction land and forest land; (3) the overall density of CL showed a declining trend, with a relatively stable spatial pattern; and (4) driving factor analysis indicates that the spatiotemporal changes in CL are jointly influenced by multiple factors, with natural factors exerting a stronger influence than socio-economic factors. Among them, the interaction between elevation and temperature had the greatest impact and served as the dominant factor. Although GDP and population were not dominant individually, their explanatory power and sensitivity increased significantly when interacting with other factors, making them key sensitive factors. The results can provide a scientific reference for the protection and rational utilization of CL resources in KR. Full article

Global warming poses a growing threat to winter wheat production in Henan Province, a critical region for China’s food security, necessitating a quantitative assessment of climate impacts. This study aimed to quantify the dominant climatic drivers of winter wheat yield and assess its spatiotemporal evolution and future risks under climate change, thereby providing a scientific basis for targeted adaptation strategies. Thus, the APSIM model in combination with the Geodetector method was applied to quantify the spatiotemporal response of winter wheat yield to climate change in Henan Province under historical (1957–2020) and SSP245 scenarios. The study results demonstrated significant trends in climatic factors during the winter wheat growing season: precipitation decreased by an average of 3.09 mm/decade, sunshine hours declined by 36 h/decade, wind speed reduced by 0.447 m/(s·decade), and evaporation decreased by 14.7 mm/decade. In contrast, the accumulated temperature ≥ 0 °C significantly increased by 70.9 °C·d/decade. Geodetector analysis further identified accumulated temperature as the dominant climatic driver (q = 0.548), followed by precipitation (q = 0.340) and sunshine hours (q = 0.261). Yield simulations from 1960 to 2018 indicated that most regions maintained stable or slightly increasing yields (<50 kg·ha⁻¹·decade⁻¹), though some areas experienced fluctuating declines. Under future scenarios, major production regions in Henan Province (Zhengzhou, Xinxiang, Luoyang) are projected to see substantial yield increases, with growth rates of 147.2–148.9 kg·ha⁻¹·decade⁻¹. Specifically, Xinxiang is expected to achieve yields of 6200 kg·ha⁻¹. The frequency of climate-induced negative yield years decreased by approximately 35% after 2003, highlighting the role of improved agricultural technologies in enhancing climate resilience. This study clarifies how multiple climatic factors jointly affect winter wheat yield, identifying rising accumulated temperature and water stress as key future constraints. It recommends optimizing varietal selection and cultivation practices according to regional climate patterns to improve policy relevance and local applicability. Full article