Search Results (7,626)

Feijoa fruits are known for their pronounced post-harvest ripening. Phytopathogen-infected specimens pose a significant risk to storage stability and overall fruit quality. Early detection and removal of defective fruits during the initial storage stages are critical for maintaining market value and preventing the spread of disease. In this study, we analyze how the multispectral reflectance properties of the feijoa surface change in response to various defects. ‘Superba’ cultivar fruits were selected, including healthy controls and samples exhibiting bruises, anthracnose, stink bug damage, tissue suberization, and gray mold. Biochemical analyses were conducted to measure the levels of organic acids, sugars, ascorbic acid, and total polyphenols. Multispectral imaging was performed with a 12-channel camera operating in the 400–1000 nm wavelength range. Results showed that the fruits affected by gray mold had the lowest concentrations of malic and citric acids but the highest levels of succinic acid. Fruits with anthracnose or insect damage exhibited the highest sugar content. Distinct differences in spectral reflectance were observed between healthy and affected areas of fruit. Based on these findings, an image processing algorithm for defective fruit detection was developed. Full article

Castanea henryi is one of the important fruit tree species cultivated in the mountainous regions of China. Castanea henryi is a starch-accumulating type. As an intracellular substance, starch plays an important role in maintaining cell turgor and sustaining fruit firmness. Although starch metabolism has been extensively studied in model and fruit crops, its regulatory mechanisms in Castanea henryi remain poorly understood. This review synthesizes recent advances in starch physicochemical properties, metabolic pathways, and regulatory mechanisms during fruit development, seed germination, and postharvest storage. Current knowledge gaps, including limited molecular characterization and gene functional analysis in Castanea henryi, are highlighted. This review provides a framework for future research and breeding strategies aimed at improving fruit quality and storage performance. Full article

Environmental temperature-induced metabolic changes in dams can be reflected by alterations in metabolomic and fatty acid profiles in colostrum. The colostrum from 13 Black Bengal (BB) dams was collected on the day of parturition at two consecutive parities during the hot conditions (HCs) of summer or rainy seasons and the cold conditions (CCs) of winter. The metabolomic and fatty acid profiles were analyzed using nuclear magnetic resonance (NMR) and gas chromatography–mass spectrometry, respectively. The results showed significantly higher sarcosine, tyrosine, citrate, succinate, galactose, acetylglucosamine, carnitine, choline, glycerophosphocholine, and trimethylamine N-oxide during CCs than HCs; potential discriminant metabolites according to VIP scores were sarcosine, succinate, and choline. Colostrum from CCs had significantly lower levels of saturated fatty acids (SFAs), including butyric acid (C4:0), myristic acid (C14:0), and pentadecanoic acid (C15:0), but higher omega-9 monounsaturated fatty acids (MUFAs), especially oleic acid (C18:1n9c), elaidic acid (C18:1n9t), and eicosenoic acid (C20:1n9), than in HC. Linoleic acid (C18:2n6c) and the omega 6/omega 3 PUFA ratio were higher during CCs than HCs. It is concluded that a metabolic shift for nutrient utilization occurs, from glucose during HCs toward fat during CCs, which may not be due to the diet but rather neurohumoral alterations occurring during temperature adaptation. Full article

Chilli is a major horticultural crop in tropical and subtropical regions that contributes substantially to the global culinary and economic sectors. However, anthracnose remains one of the most destructive diseases, causing severe losses in both field and stored fruits. Current management strategies offer limited long-term effectiveness, highlighting the need for sustainable alternatives. This study developed nanoemulsions (NEs) from Garcinia atroviridis fruit extract and evaluated their biocontrol potential against Colletotrichum capsici alone and in combination with Trichoderma harzianum. Two formulations, NE4 and NE7, exhibited good thermostability without phase separation at 25 and 54 °C, with droplet sizes of 135.1 and 124.1 nm, respectively, and were non-phytotoxic to chilli seedlings. In vitro, the nanoemulsions significantly suppressed C. capsici mycelial growth (62%) compared to the crude extract. Under rain shelter conditions, NE integrated with T. harzianum (T7 and T8) was highly effective in delaying disease onset and reducing disease severity, achieving 90.07% and 88.37% relative disease reduction, respectively. These treatments also produced the highest marketable yields, comparable to the synthetic fungicide Dithane M-45^® (2 g L⁻¹). In contrast, the untreated control group exhibited an 83% yield loss. The results indicate that nanoemulsions of G. atroviridis fruit extract, particularly when combined with T. harzianum, offer a promising and sustainable biological control option for managing pre-harvest chilli anthracnose. Their incorporation into integrated pest management programmes may reduce dependence on chemical fungicides and support safer chilli production systems. Full article

Intensive nitrogen (N) fertilization in Phyllostachys edulis (Carrière) J.Houz. forests increases productivity but also accelerates nitrous oxide (N₂O) emissions, posing a challenge to balancing forest yield with environmental sustainability. Silicon (Si), a beneficial element for bamboo, has emerged as a potential regulator of soil nitrogen (N) cycling, but its role in controlling N₂O emissions in forest ecosystems is not fully understood. In this study, we conducted a factorial pot experiment using P. edulis forest soil, with data collected over two years, but only the second-year results were analyzed, with controlled N (0, 80, and 160 mg kg⁻¹) and Si (0, 25, and 50 mg kg⁻¹) additions. The experiment lasted two years, but only the second-year data were used for analysis. We investigated how Si affected soil inorganic N dynamics, enzyme activities, plant growth, and cumulative N₂O emissions. Si addition significantly reduced N-induced N₂O emissions by up to 53%, with the strongest mitigation observed under moderate N input (p < 0.05, two-way ANOVA). This effect was associated with lower activities of AMO, NaR, and NiR, together with reduced availability of oxidized N substrates, indicating that Si mitigated N₂O emissions mainly by constraining upstream N transformation processes rather than by directly suppressing N₂O fluxes. Si addition also tended to promote plant biomass accumulation. These findings suggest that integrating Si fertilization into bamboo forest management may help improve nutrient use efficiency while mitigating greenhouse gas emissions. Full article

Understanding the mechanisms driving patterns of alpha and beta-diversity through temporal variation in taxonomic diversity remains a fundamental question in community ecology surveys. Insects represent a species-rich group playing several roles in ecological processes. However, knowledge of their temporal distribution and seasonality remains limited, particularly in subtropical regions. We investigated intra-annual patterns of alpha and beta-diversity of butterflies in Restinga ecosystems of southern Brazil, a subtropical region characterised by marked seasonality. Butterflies were monitored throughout one year using Malaise interception traps, and data were grouped by season. We tested seasonal differences in temperature and humidity and evaluated their association with patterns of richness, abundance, evenness, and species composition. Temperature was the main environmental filter structuring butterfly assemblages compared to humidity. Butterfly richness and abundance peaked in summer, followed by spring, coinciding with higher temperatures, while diversity declined markedly during winter. Although we expected winter assemblages to represent nested subsets of other seasons, beta-diversity analyses revealed high species turnover among seasons. Our findings demonstrate that temperature drove the structure of butterfly assemblages across seasons, highlighting the importance of monitoring to increase knowledge on the temporal dynamics and distribution of insects in the subtropical region. Full article

Precipitation is a fundamental element in terrestrial water circulation and ecosystem hydrological balance. The occurrence of concentrated precipitation is closely linked to vegetation growth and soil fertility rather than accumulated or averaged precipitation. Despite its importance, the characteristics of continuous precipitation and its specific effects on vegetation cover remain uncertain. In this study, we formulated a new continuous precipitation index system, including $C{P}_d$ (continuous precipitation days); $AC{P}_t$ (annual continuous precipitation times); $C{P}_a$ (continuous precipitation amount); and $FCP$ (frequency in different ranges of $AC{P}_a$). We utilized daily precipitation data from 467 meteorological stations across China, which were divided into eight vegetation type regions. We observed that the spatial distribution of continuous precipitation differed to varying degrees from accumulated precipitation. The national average of $MAC{P}_a$ for a single event was 16.7 mm, ranging from 3.8 mm in the temperate desert region to 37.1 mm in the tropical monsoon forest and rainforest region. Similarly, the national average of $MC{P}_d$ ($MMC{P}_d$) for a single event was approximately 2.3 or 9 days. At the regional level, the tropical monsoon forest and rainforest region experienced the longest $MMC{P}_d$. Furthermore, the national average of $MAC{P}_t$ occurrences for 1 year was 57.7 times, varying from 29.8 times in the temperate desert region to 77.9 times in the tropical monsoon forest and rainforest region. Vegetation responses to precipitation regimes exhibit significant regional heterogeneity across China. Our analysis reveals that $MAC{P}_t$ and $M{P}_a$ show markedly positive correlations with vegetation growth. In subtropical monsoon climate zones, particularly the Yunnan–Guizhou Plateau and Qinling Mountains, $MAC{P}_t$ demonstrates strong positive correlations (r = 0.6–1.0) with NDVI, where sustained rainfall provides stable moisture availability for vegetation. While a positive correlation between vegetation (NDVI) and mean annual consecutive precipitation is observed in some arid northern regions, in ecosystems such as the Loess Plateau (TG/TM), vegetation growth shows greater dependence on $M{P}_a$, highlighting the crucial role of total precipitation amount in water-limited ecosystems. Notably, extreme precipitation events display dual effects on vegetation dynamics. Prolonged heavy rainfall ($MMC{P}_d$/$MMC{P}_a$) exhibits significant negative impacts on NDVI (r = −1.0 to −0.6) in topographically complex regions, including the Hengduan Mountains and Yangtze River Basin (SE), likely due to induced soil erosion and waterlogging stress. Our findings underscore the importance of incorporating continuous precipitation indices to evaluate and forecast the influence of precipitation on ecosystem stability. This understanding is vital for developing informed conservation and management strategies to address current and future climate challenges. Full article

Bactrocera dorsalis (Hendel) is a major fruit-feeding pest that poses a severe and persistent threat to the horticulture industry in tropical and subtropical regions. Methyl eugenol (ME) is a powerful male-specific attractant phytochemical and pheromone precursor that has been widely exploited in lure-and-kill pest management programs. Upon ingestion, ME is metabolized (E)-coniferyl alcohol (E-CF) and 2-allyl-4,5-dimethoxyphenol (DMP), which are stored in the male rectal glands and released during courtship to attract females. Despite its ecological significance, the fundamental molecular mechanism underlying ME perception remains poorly understood. Here, we performed a comparative transcriptomic analysis of ME-responsive and ME-non-responsive male B. dorsalis across four tissues (head, gut, midleg, and wing). A total of 15,727 genes were annotated, of which 970 were associated with odorant-binding proteins (OBPs), odorant receptors (ORs), gustatory receptors (GRs), ionotropic receptors (IRs), and chemosensory proteins (CSPs), as well as detoxification families comprising cytochrome P450s (CYPs), carboxylesterases (CaEs), glutathione S-transferases (GSTs), and uridine diphosphate (UDP)-glycosyltransferases (UGTs), and the stress-related heat shock proteins (HSPs) genes. Differential expression analysis identified 7222, 7763, and 6105 differentially expressed genes (DEGs) in the head, gut, and wings/midlegs, respectively, between ME-responsive and ME-non-responsive males. Notably, CYPs, UGTs, and HSPs involved in detoxification and stress response were significantly downregulated. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses revealed that CYPs were significantly enriched in metabolic detoxification pathways. These findings reveal a complex molecular interplay between olfaction and detoxification and suggest that ME induces coordinated genetic pathways supporting survival, reproduction, and environmental adaptability. This knowledge provides a foundation for the development of eco-friendly pest management strategies targeting these molecular mechanisms. Full article

Alternaria brown spot, caused by the tangerine pathotype of Alternaria alternata, is a destructive fungal disease affecting citrus production worldwide. Nucleotide-binding site-leucine-rich repeat (NBS-LRR) genes constitute a major class of plant immune receptors; however, their genome-wide characteristics and potential association with Alternaria brown spot resistance loci in citrus remain poorly understood. In this study, we performed a comprehensive genome-wide identification and comparative analysis of NBS-LRR genes across representative citrus species. A total of 417 and 326 NBS-LRR genes were identified in Citrus reticulata and Citrus clementina, respectively, and were classified into NL, CNL, TNL, and RNL subfamilies based on domain architecture. Phylogenetic reconstruction, gene structure analysis, conserved motif composition, chromosomal distribution, synteny relationships, and promoter cis-element profiling collectively revealed considerable structural variation and lineage-specific expansion of the NBS-LRR gene family in citrus genomes. By integrating previously reported quantitative trait locus (QTL) data for Alternaria brown spot, we identified several NBS-LRR genes located within a resistance-associated genomic interval on chromosome 3. Among these, a candidate gene, designated LRR2, exhibited differential transcriptional responses upon pathogen inoculation and displayed distinct sequence variations between citrus genotypes. Structural modeling and molecular docking analyses suggested potential binding interfaces between LRR2 and multiple host-selective toxins, although the biological relevance of these interactions requires further experimental validation. Subcellular localization assays in Nicotiana benthamiana showed that LRR2 is distributed in both the nucleus and cytoplasm. Notably, transient overexpression of LRR2 triggered hypersensitive response-like cell death and H₂O₂ accumulation. Collectively, this study provides a comprehensive overview of the citrus NBS-LRR gene family and presents a multifaceted characterization of a QTL-anchored candidate gene. These findings establish a genomic and molecular framework for further functional investigations of citrus–Alternaria interactions. Full article

Existing buildings with large glazing ratios within subtropical Mediterranean climates face substantial challenges for thermal and visual control of their indoor environment. Previous research by the same authors has already identified the potential of incorporating both solar–PDLC (polymer-dispersed liquid crystal) and SPD (suspended particle device) switchable films within facades exposed to high solar insolation to provide a wide dynamic range of visual transparencies. This paper identifies a novel application for switchable laminates within a dynamic external shading device that permits the casting of a shadow on demand onto existing fenestration. This study compares the degree of glare within an enclosed space attained by a conventional opaque overhang over a window to that achieved with glass shading overhangs incorporating two types of switchable films. Using a scale model in a field test setting, indoor illumination and glare measurements are investigated under different states of switchable films and compared to those provided by conventional static glazing, with and without ordinary external overhangs under identical field test conditions. Results show that switchable overhangs in their transparent/bleached state can allow the ingress of daylight without creating excessive glare, whereas in their translucent/tinted state, switchable shades can deliver a level of glare protection similar to that provided by an opaque shading overhang. Full article

Upper troposphere (UT) humidity records are crucial for climate studies. To maximize temporal representativeness and enhance the lidar signal, pseudo-monthly averaging—limited to nighttime measurement—is applied, yielding water vapor mixing ratio (WVMR) profiles up to 16 km. This study evaluates 11 years (2013–2023) of WVMR profiles from a UV Raman lidar (Li1200) at Réunion Island, comparing them with MLS-Aura satellite retrievals, ERA5 reanalysis data, and GRUAN-processed M10 radiosondes. The results reveal a systematic dry shift in MLS of up to 30% above 12 km, particularly during the wet season. The lidar exhibits a slight downward shift in WVMR, approximately 5% lower than ERA5 throughout the UT, with the largest deviations occurring above 14 km and greater variability during the wet season. Calibration-related challenges during the dry season result in lidar WVMR profiles that are up to 10% drier than ERA5. Additionally, comparisons with GRUAN-processed radiosondes show a substantial dry shift relative to the lidar, exceeding 30% above 12 km. We investigate the effect of GNSS-based lidar calibration by applying an alternative calibration method, which produces higher WVMR values. This reveals a dry shift in ERA5 relative to the lidar, increasing with altitude in the UT up to 25%. These measurements contribute to the global effort to monitor and validate tropical and subtropical upper tropospheric humidity. Full article

Corn, paddy, wheat, sorghum, and cassava serve as the primary energy sources in both human and animal diets. This study aimed to evaluate their nutrient release patterns in a simulated gastrointestinal environment and to assess the in vitro biological activity of the metabolites produced during digestion. The results showed that wheat exhibited the highest dry matter degradation in the stomach–jejunum–ileum digestion stage, while wheat and paddy showed the highest crude protein degradation compared with the other starch sources. In addition, wheat had a higher total free sugar concentration than paddy, sorghum, and cassava. Among the individual free sugars, such as D-sorbitol and D-(+)-trehalose, were found to have the highest concentrations in wheat, whereas cassava had the highest D(−)-fructose concentration. Several differential metabolites, including valeric acid, caproic acid, octanoic acid, and azelaic acid were highly released in paddy, whereas glucaric acid, threonic acid, phenylacetic acid, and shikimic acid were highly released in cassava, and 4-hydroxycinnamic acid was highly released in paddy and sorghum. Four unique metabolites were identified during the digestion process of five starch sources. Particularly, isocitric acid and trans-cinnamic acid were released only from cassava; caffeic acid was released only from sorghum and corn; and pimelic acid was released only from paddy and wheat. Furthermore, cassava was distinct from the other starch sources, displaying a higher abundance of differential metabolites within the glucagon signaling pathways as mapped in KEGG pathway analysis. In summary, compared with other starch sources, wheat provides more dry matter, protein, and sugars for the body. Cassava is unlikely to offer any advantage in glycemic regulation, while paddy and cassava possess stronger biological activity in terms of differential metabolites. Full article

Nitrate-rich vegetables are increasingly recognised as a key subgroup of phytochemical-dense foods that have significant potential for preventing and managing chronic diseases. Although dietary nitrates were historically approached with caution due to concerns about nitrosamine formation, contemporary evidence highlights their beneficial effects on vascular, metabolic and cognitive functions. Ageing is characterised by endothelial dysfunction, impaired nitric oxide (NO) synthesis and increased oxidative stress, which elevates cardiovascular risk. In this context, nitrate-rich vegetables offer a natural way to restore NO bioavailability and support cardiometabolic health. This narrative review provides an integrative overview of nitrate-rich vegetables as sources of bioactive phytochemicals with therapeutic relevance. We summarise the biochemical pathways of nitrate and nitrite metabolism, including the enterosalivary nitrate–nitrite–NO cycle, the role of oral microbiota, and red blood cell-mediated nitrite reduction. Particular emphasis is placed on NOS-independent NO production, which becomes increasingly important with age, and on the synergistic interactions between dietary nitrates and other phytochemicals such as polyphenols, vitamin C, flavonoids and betalains. These compounds enhance NO stability, reduce oxidative stress, modulate inflammatory signalling and support mitochondrial function, thereby amplifying the health benefits of nitrate-rich vegetables. Beetroot, with its high nitrate content and distinctive antioxidant profile, is highlighted as a prime example. Clinical and mechanistic studies suggest that nitrate-rich vegetables may lower blood pressure, improve endothelial function and cerebral perfusion, enhance cognitive performance and muscle oxygenation, and increase exercise efficiency, particularly in older adults. Additional benefits include anti-inflammatory effects, modulation of platelet function and improvements in metabolic parameters, all of which are relevant to the prevention of chronic diseases such as hypertension, type 2 diabetes and atherosclerosis. While dietary nitrate is generally considered low-risk for healthy adults, caution is warranted in susceptible populations, such as infants and individuals with impaired renal function. Finally, significant research gaps remain, including the need for long-term, well-controlled trials and personalised strategies that account for variability in microbiota composition and nitrate metabolism between individuals. Full article

Papaya (Carica papaya L.) is a widely cultivated tropical and subtropical fruit crop valued for its rich nutritional content, diverse food industry applications, and the medicinal use of papain. However, bitterness in papaya fruit, particularly in fibrous strands, negatively affects fruit quality and consumer acceptance; therefore, the development of papaya cultivars with stable and desirable quality is of great importance. To identify the bitter compounds in papaya fruit fibrous strands and elucidate the molecular mechanisms underlying their biosynthesis, we performed transcriptomic and metabolomic analyses of fibrous strands from two papaya cultivars at three developmental stages. We identified carpaine, dehydrocarpaine II, and their derivative alkaloids. Furthermore, we identified two key regulatory genes, CpNAC82 and CpHD-Zip ANT2, associated with alkaloid biosynthesis. Finally, using single-nucleus RNA sequencing technology, we constructed a comprehensive gene expression atlas of papaya fibrous strands and stems, successfully identifying multiple cell types, including epidermal cells, guard cells, parenchyma cells, and phloem cells. Epidermal and phloem cells serve as the primary sites of alkaloid metabolism in papaya. These findings provide new insights into the molecular mechanisms of bitterness in papaya’s fibrous strands and yield genomic resources for improving fruit quality in papaya. Full article

Continuous monocropping and inappropriate fertilization have contributed to nutrient depletion and soil degradation, limiting peanut productivity in subtropical red soil agroecosystems. Although diversified cropping may help alleviate these constraints, the reasons why it improves peanut productivity remain unclear. In this study, we conducted a long-term field experiment in Jiangxi, China, to compare four cropping systems, assess soil nutrients, peanut productivity, and bacterial communities, and further evaluate the role of key taxa through inoculation assays and structural equation modeling. Results showed that diversified cropping improved peanut growth and yield, with the green manure integrated system performing best overall. Diversified cropping also increased soil organic carbon, total nitrogen, and available phosphorus, while reshaping bacterial communities. Several taxa, including Bradyrhizobium, Mycobacterium, Dormibacter, and Ardenticatena, were positively associated with soil nutrients. Inoculation assays further showed that a synthetic consortium assembled from representative strains affiliated with key taxa produced stronger effects on plant growth than a single-strain inoculation. Structural equation modeling identified key taxa as the factor most strongly associated with crop productivity. These findings suggest that higher peanut productivity under diversified cropping was closely associated with concurrent improvements in soil fertility and the enrichment of key taxa. Full article