Search Results (35)

Meripilus giganteus (Pers.) P. Karst. is a basidiomycete fungus known for its bioactive properties, including antioxidant, antimicrobial, and cytotoxic effects. Although research has largely focused on fruiting bodies, mycelium obtained through in vitro culture offers a sustainable and potentially scalable source of bioactive metabolites. This study aimed to compare the chemical composition and biological activity of extracts from the fruiting bodies and mycelium of M. giganteus. Key compound groups were analyzed using high-performance liquid chromatography (HPLC), and biological activity was assessed through DPPH and ABTS antioxidant assays and MTT-based cytotoxicity testing on human gastrointestinal cancer and normal colon epithelial cell lines. The results revealed distinct metabolite profiles between fungal forms and demonstrated that solvent type strongly influenced extraction efficiency. Cytotoxicity assays indicated moderate activity of both extract types, with some selectivity towards colorectal cancer cell lines. These findings suggest that M. giganteus mycelium may serve as a promising alternative to fruiting bodies for the production of antioxidant and potentially chemopreventive compounds. Further studies are recommended to optimize cultivation and extraction conditions to enhance both metabolite yield and biological activity. Full article

Zanthoxylum planispinum var. Dingtanensis (hereafter Z. planispinum) has excellent characteristics, including Ca and drought tolerance. It can flourish in stony soils, and it is used as a pioneer plant in karst rocky desertification control. However, soil degradation, coupled with the removal of nutrients absorbed from the soil by Z. planispinum’s fruit harvesting, exacerbates nutrient deficiency. The effects of fertilization on soil nutrient utilization and microbial limiting factors remain unclear. Here, we established a long-term (3 year) field experiment of no fertilization (CK), organic fertilizer + chemical fertilizer + sprinkler irrigation (T1), chemical fertilizer + sprinkler irrigation (T2), chemical fertilizer treatment (T3), and leguminous (soybean) + chemical fertilizer + sprinkler irrigation (T4). Our findings indicate that fertilization significantly improved the nutrient uptake efficiency of Z. planispinum, and it also enhanced urease activity compared with CK. T1 increased soil respiration and improved water transport, and the soil nutrient content retained in T1 was relatively high. It delayed the mineralization rate of organic matter, promoted nutrient balance, and enhanced enzyme activity related to the carbon and nitrogen cycle. T4 caused soil acidification, reducing the activity of peroxidase (POD) and polyphenol oxidase (PPO). The soil microbial community in the Z. planispinum plantation was limited by carbon and phosphorus, and T1 mitigated this limitation. This study indicated that soil nutrient content regulated enzymatic activity by influencing microbial resource limitation, with organic carbon being the dominant factor. Overall, we recommend T1 as the optimal fertilization strategy for Z. planispinum plantations. Full article

As the fundamental unit of soil structure, soil aggregates play a crucial role in enhancing soil carbon and nitrogen storage, thereby supporting soil fertility and overall health, particularly in fragile karst regions. This study aims to quantify the effects of various ecological construction measures on soil aggregate stability, including focusing on geometric mean diameter (GMD), mean weight diameter (MWD), and K values, as well as aggregate-related organic carbon (SOC) and total nitrogen (TN), soil mechanical composition, and aggregate content. The ecological construction measures examined include plantation forests (Y7th–rgl), restored forests (Y6th–zr), fruit forests (Y6th–jgl), and contour reverse slope terraces (Y1th–crt). Compared to sloping farmland, contour reverse slope terraces, with their distinctive priority induction function, significantly increased the content of medium-fine particle aggregates, greater than 87%. Among the ecological construction measures, plantation forests exhibited the highest aggregate stability, with an average increase ranging from 8% to 157%. Notably, microaggregates, regardless of size, possessed the highest carbon and nitrogen contents, contributing significantly to soil carbon and nitrogen pools. Furthermore, both plantation and contour reverse slope terrace treatments demonstrated an equal contribution of carbon and nitrogen across all aggregate sizes. The partial least squares path modeling (PLS-PM) analysis indicates that land use type and the content of carbon and nitrogen pools are the primary factors influencing soil aggregate stability. These findings suggest that plantations are particularly effective in enhancing soil and water conservation in fragile karst areas, while the contour reverse slope terrace method shows potential for stabilizing soil structure over extended time scales due to its unique “preferential entrainment” function. Full article

Soil in the karst region usually features high geogenic cadmium (Cd) and limited available phosphorus (P). Appropriate phosphate amendment is crucial for alleviating Cd accumulation in food crops and reducing health risks. However, the interaction of Cd and P in geogenic Cd-rich soil-plant systems is poorly understood. In this study, a pot experiment was conducted to investigate the translocation of Cd in the soil-pepper system under different amendment rates of Ca(H₂PO₄)₂. The results showed that the biomass of pepper was not affected by the application rates of Ca(H₂PO₄)_2, even up to 0.45 g/kg, but was affected by the application of nitrogen and potassium fertilizers. High contents of total Cd (6.19 mg/kg) and bioavailable Cd (2.72 mg/kg, 44%) in the studied soils resulted in elevated Cd content in pepper, and it decreased in the order of root (8.18 mg/kg) > stem (4.89 mg/kg) > fruit (3.88 mg/kg). This indicates that pepper planted in the studied soils may present potential health risks. Furthermore, phosphate amendment neither influences the bioavailable Cd in rhizosphere soil nor Cd uptake and transport in pepper plants. The findings of this study highlight that monocalcium phosphate is not a suitable choice for reducing the accumulation of Cd in pepper fruits in the studied soil and that other remediation strategies are needed. Full article

Crop rotation is widely recognized as a key strategy to mitigate the adverse effects associated with continuous cropping. Recent studies have demonstrated that biochar has a significant potential for preventing and controlling these challenges. However, the ameliorative effects of green manure rotation and biochar application on continuous pepper cultivation in the karst mountainous regions of Southwest China remain largely unexplored. To address this gap, a field experiment was conducted from 2020 to 2023 to investigate the effects of green manure rotation and biochar application on the continuous cropping of peppers. The experiment consisted of five treatments: CK (no green manure and no biochar), WP (winter fallow and conventional pepper production with chemical fertilization), GP (green manure and pepper rotation, the amount of fresh green manure returned to the field was about 15 t·ha⁻¹), WP + B (winter fallow and pepper rotation with 1500 kg·ha⁻¹ of biochar applied during the pepper season), and GP + B (green manure and pepper rotation with 1500 kg·ha⁻¹ of biochar applied during the pepper season, the amount of fresh green manure returned to the field was about 15 t·ha⁻¹). The results showed that all the improved measures (GP, WP + B, GP + B) increased the yield of fresh pepper and dry pepper by 26.97–72.98% and 20.96–65.70%, respectively, and the yield of dry pod pepper increased by 14.69–40.63% and 21.44–73.29% in 2021 to 2023, respectively, and significantly improved the yield stability and sustainability of continuous cropping of peppers compared with WP treatments. In addition, green manure rotation or biochar application alone or in combination enhanced the nutritional quality of pepper fruits by increasing the content of free amino acids (8.62–19.42%), reducing sugars (15.30–34.62%) and vitamin C (26.19–43.52), and decreasing the nitrate content (26.93–40.17%). Furthermore, the application of green manure rotation or biochar alone or in combination significantly improved the absorption of nitrogen (23.73–60.23%), phosphorus (18.12–61.71%), and potassium (20.57–61.48%) nutrients in the continuous cropping of peppers, which contributed to the improvement of fertilizer use efficiency. Notably, GP + B treatment not only improved the yield and quality of continuous cropping peppers but also resulted in higher production value and net income compared to the GP and WP + B treatments. In conclusion, the combination of green manure rotation and biochar application represents an effective strategy for mitigating the challenges of continuous cropping in pepper cultivation within the karst mountainous regions of Southwest China. Full article

This study explores the correlation between soil nutrient elements and pepper fruit quality in Guizhou Province, highlighting regional variations in nutrient influence. Guizhou, with its unique mountainous and karst terrain, provides a distinct ecological environment for pepper cultivation. Our analysis of three major pepper-growing regions—Dafang, Guiyang, and Zunyi—demonstrates that the nitrogen, phosphorus, and potassium levels in the soil significantly impact pepper quality. Potassium plays a particularly vital role in fruit development, as deficiencies in potassium often result in flower and fruit drop and reduced yield. In Dafang, AP (available phosphorus) and TK (total potassium) were most closely linked to amino acids, reducing sugars, and capsaicinoid content, while in Bozhou, SAN (available nitrogen) was most influential, and in Qingzhen, TP (total phosphorus) and AK (available potassium) were predominant. The findings suggest that key soil elements, such as available phosphorus, available potassium, available nitrogen, and organic matter, influence the quality indicators—amino acids, reducing sugars, capsaicin, and dihydrocapsaicin—in pepper fruits. Further analysis indicates that Guizhou’s distinct soil composition significantly contributes to its peppers’ unique flavor profile. The combined effects of soil nutrients, pepper varieties, and cultivation practices underline the superior quality of Guizhou peppers. This study provides a foundation for understanding the soil–quality interaction and enhances the market recognition of Guizhou’s pepper varieties. Future research should investigate the integrated effects of environmental and soil factors to better assess Guizhou’s favorable growth conditions for peppers. Full article

Inonotus hispidus (Bull.) P. Karst., is a medicinal fungus, which parasitizes broad-leaved tree such as Morus alba L., Fraxinus mandshurica Rupr., and Ulmus macrocarpa Hance. To elucidate the internal relationship between I. hispidus and its hosts, this study analyzed endophytic bacteria and fungi in the roots of M. alba and F. mandshurica growing I. hispidus using the 16S rDNA and ITS high-throughput sequencing technologies; and conducted widely targeted metabolomics research using UPLC-MS/MS. The results showed that Cyanobacteria and unidentified chloroplasts had the highest relative abundance at the phylum and genus levels, respectively. For endophytic fungi, Ascomycota was dominant at the phylum level, while Pleosporales gen Incertae sedis and Oncopodiella were the dominant genera in the roots of M. alba and F. mandshurica, respectively. Widely targeted metabolomics identified 562 differential metabolites and 46 metabolic pathways. Correlation analysis revealed that Xanthobacteraceae, Pseudorhodoplanes, and Bauldia were potential regulators of phenolic acids and phenylpropanoids biosynthesis. Additionally, the genus Oncopodiella was primarily associated with the enrichment of lipids, amino acids, sugars, phenolic acids, and other compounds. This result provides significant insights into the size of the fruiting body, resource development, and active ingredients of I. hispidus from different tree sources. Full article

Differences in land use type and chronological age affect soil properties and plant community characteristics, which may influence soil structural stability and erodibility. However, knowledge on the effects of soil physicochemical properties on soil aggregate stability and erodibility at different land use years is limited. This study selected five land use types: corn field (Year 38^th-y), corn intercropped with cabbage field (Year 38^th-y + b), fruit and meridian forest (Year 6^th-jgl), naturally restored vegetation (Year 6^th-zr), and artificial forest (Year 7^th-rgl) in the karst landscape of the Chishui River Basin in Yunnan Province. We aimed to identify the influencing factors of soil stability and erodibility under different land use time series. The results indicated that the mean weight diameter (MWD), the geometric mean diameter (GMD), and soil structural stability index (SSI values) were highest in Y6^th-zr and lowest in Y7^th-rgl. Conversely, the erodibility K value was lowest in Y6^th-zr, suggesting that the soil structure in Y6^th-zr exhibited greater stability, whereas soil stability in Y7^th-rgl was lower. Redundancy and throughput analyses revealed that organic carbon and water-stable aggregates > 2.0 mm content had higher vector values. Soil bulk density, total nitrogen, organic carbon, and soil texture content were the main factors contributing to soil stability variation (0.338–0.646). Additionally, total nitrogen, organic carbon, total phosphorus, and soil texture content drove the variation in K values (0.15–1.311). Natural vegetation restoration measures can enhance soil structure to a certain extent. These findings highlight changes in soil aggregate stability and erodibility over different land use durations. The research results have important theoretical and practical significance for understanding the differences in soil erosion and soil restoration under different land use patterns in the karst landscapes of southwest China. Full article

The feeding posture of a group of François’ langurs in Fusui County, Guangxi, was studied using instantaneous scan sampling from January to December 2016 to explore how the species adapts to karst limestone forests by collecting data on feeding posture, forest strata height, and substrate use. The results showed that leaves were the main food type of the François’ langurs, with young leaves accounting for 64.97% ± 19.08% of the food composition, mature leaves accounting for 11.88% ± 12.09%, fruits accounting for 12.96% ± 12.89%, flowers accounting for 4.16% ± 4.06%, and other food types, including stems, petioles, and other unknown parts of the tree, accounting for a total of 6.03% ± 9.09%. The François’ langurs had four main postures during feeding, of which sitting and bipedal standing feeding accounted for the largest proportions, at 85.99% ± 5.97% and 12.33% ± 6.08% of the total records, respectively. Quadrupedal standing and suspending were rarely observed and only appeared occasionally during feeding activities at the peak resting period, the two postures together accounting for 1.39% ± 1.59% of the total records. The feeding postures of the langurs had marked seasonal variation, as evidenced by the fact that seated feeding accounted for a significantly higher proportion of the total behavioral records in the rainy season than in the dry season, whereas feeding while standing bipedally was significantly more frequent during the dry season. Correlation analyses showed that feeding posture was correlated with food composition, showing a positive correlation between the proportion of bipedal standing feeding and mature leaf consumption. François’ langurs preferred to forage in the lower and middle forest layers, with the lower forest layer accounting for 55.93% ± 16.50% of the total number of recordings and the middle forest layer accounting for 33.63% ± 18.33%. Langurs were less likely to forage on the ground (rocks), accounting for only 6.79% ± 4.78% of the records. The frequency of langurs feeding in the upper part of the forest layer was the lowest at 3.65% ± 2.73%. Additionally, in the dry season, langurs utilized the lower forest layer more but used the middle forest layer less than in the rainy season. This study demonstrates that the spatial distribution of foods in the limestone forest has an important effect on the feeding posture of François’ langurs and their forest layer utilization. Full article

Changes in the spatial pattern of land use are inextricably linked to the ecosystem environment, and the assessment of regional eco-environment quality can help provide sustainable and healthy development strategies for heritage management organizations. In this study, based on RS and GIS technologies, we quantitatively analyzed the characteristics of land use changes in the Shibing Karst World Natural Heritage site from 2000 to 2020, and introduced the regional eco-environment quality assessment index for quantitative factor analysis. The results show that: (1) The heritage site is mainly dominated by forest and shrub, with more aggregated cropland, and impervious surfaces in the buffer zone. The area of shrub has increased during the 20-year period, occupying 12.63% of the total transferred area. Cropland has been basically converted to forest, accounting for more than 60% of the total transferred area, followed by shrubs, which have been basically transferred to ecologically better land types. (2) By analyzing the attitude of motivation, forest, shrub, and water have positive values, while cropland, grassland, and impervious surfaces have negative values. Grassland has the largest absolute value of kinetic attitude, and the smallest is for water. The integrated dynamic attitude is basically maintained at 24%, showing a state of rapid and then stable land category conversion. (3) Over the past 20 years, the regional eco-environment quality index has been stable between 0.68 and 0.71, and shows a trend of rapid growth and stabilization, which is consistent with the comprehensive attitude. The conversion between cropland, forest, and shrubs is the main cause of ecological improvement and deterioration. Overall, the relevant conservation measures at the site and China’s corresponding responses to global climate change have led to a stabilization and increase in the regional ecological quality of the site. The management measures of the relevant authorities have begun to bear fruit, but further promotion of the sustainable development of the site is needed to provide a scientific model for the conservation of other karst heritage sites. Full article

In recent years, a significant impediment to the advancement of China’s agricultural sector is the noteworthy challenge posed by diminished crop yields and quality due to ongoing continuous cropping obstacles. Numerous studies have consistently showcased the potential of plant growth-promoting rhizobacteria (PGPR) and biochar in augmenting the alleviation of continuous cropping barriers. Nevertheless, the potential of PGPR and biochar to remediate and improve continuous cropping peppers in the karst yellow soil area remains unclear. A 2-year field experiment was implemented to examine the impact of PGPR and biochar, when applied alone or in combination, on the production potential of continuous cropping peppers. The results revealed that PGPR and biochar significantly elevated the yield of fresh and dry pepper compared with TF treatment. The utilization of PGPR and biochar resulted in an augmentation of free amino acids, soluble sugar, and vitamin C content in pepper fruits, but a reduction in the nitrate content, which proved advantageous in enhancing the overall quality of peppers. Furthermore, the use of PGPR and biochar demonstrated significant benefits in enhancing NPK accumulation, fertilizer utilization, and economic efficiency. Nevertheless, the co-application of PGPR and biochar yielded significantly better results compared to their individual application. In conclusion, the utilization of PGPR and biochar demonstrated a favorable impact on the productivity and economic benefits of continuous cropping peppers. The simultaneous application of PGPR and biochar represents a promising approach to enhancing yield and improving the quality of peppers in the karst yellow soil region of Southwest China. Full article

The comprehensive exploration and thorough understanding of the physicochemical characteristics of “Crystal” grapes in the Karst area of Southwest China can not only produce edible table grapes, but also offer significant theoretical backing for the management of rocky desertification in the Karst area and consequently generate enhanced social and ecological benefits. This study explored the regulatory effect of 1-MCP fumigation on the postharvest storage quality of "Crystal” grapes, aiming to provide some technical support for the development of the grape industry in the Karst mountainous areas. The results indicate that compared with the control group, both the 10.0 and 50.0 μL/L 1-MCP treatment groups effectively inhibited the increase in decay rate, browning rate, shedding rate, and color change of the grapes, significantly inhibited the enhancement of polyphenol oxidase (PPO), peroxidase (POD), and lipoxygenases (LOX) browning-related enzyme activities, improved the superoxide dismutase (SOD) activity of the fruits, hindered the decrease of ascorbic acid (AsA) and polyphenols, delayed the accumulation of malondialdehyde (MDA) content, and significantly postponed the peak period of polygalacturonase (PG) activity in the fruits and the degradation of protopectin to soluble pectin, thereby maintaining desirable texture characteristics. The utilization of 1-MCP for fruit fumigation yielded a heightened overall fragrance, thereby facilitating the emission of terpenes, alcohols, aldehydes, ketone aromatic compounds, and methyl aromatic substances within the fruit. Overall, both the M10 and M50 treatments are equally effective in preserving the storage quality of “Crystal” grapes. Under the condition of ensuring the excellent edible quality of crystal grapes, M2 can extend the shelf life of crystal grapes by about 5 days, and M10 and M50 can extend the storage period of crystal grapes by 10~15 days. Considering the cost, it is recommended that the industry employs a concentration of 10.0 μL/L of 1-MCP for “Crystal” grapes. Simultaneously, this study also provides theoretical support for the ecologically high-quality development of cultivated land in the Karst mountainous area of Guizhou and tree selection. Full article

The Pitaya industry is a specialty fruit industry in the mountainous region of Guizhou, China. The planted area in Guizhou reaches 7200 ha, ranking first in the country. At present, Pitaya planting lacks efficient yield estimation methods, which has a negative impact on the Pitaya downstream industry chain, stymying the constant growing market. The fragmented and complex terrain in karst mountainous areas and the capricious local weather have hindered accurate crop identification using traditional satellite remote sensing methods, and there is currently little attempt made to tackle the mountainous specialty crops’ yield estimation. In this paper, based on UAV (unmanned aerial vehicle) remote sensing images, the complexity of Pitaya planting sites in the karst background has been divided into three different scenes as complex scenes with similar colors, with topographic variations, and with the coexistence of multiple crops. In scenes with similar colors, using the Close Color Vegetation Index (CCVI) to extract Pitaya plants, the accuracy reached 92.37% on average in the sample sites; in scenes with complex topographic variations, using point clouds data based on the Canopy Height Model (CHM) to extract Pitaya plants, the accuracy reached 89.09%; and in scenes with the coexistence of multiple crops, using the U-Net Deep Learning Model (DLM) to identify Pitaya plants, the accuracy reached 92.76%. Thereafter, the Pitaya yield estimation model was constructed based on the fruit yield data measured in the field for several periods, and the fast yield estimations were carried out and examined for three application scenes. The results showed that the average accuracy of yield estimation in complex scenes with similar colors was 91.25%, the average accuracy of yield estimation in scenes with topographic variations was 93.40%, and the accuracy of yield estimation in scenes with the coexistence of multiple crops was 95.18%. The overall yield estimation results show a high accuracy. The experimental results show that it is feasible to use UAV remote sensing images to identify and rapidly estimate the characteristic crops in the complex karst habitat, which can also provide scientific reference for the rapid yield estimation of other crops in mountainous regions. Full article

There is an increased interest in the hydroponic production of strawberries in protected cultivation systems, and it is, therefore, urgent to develop new, more sustainable growing media alternatives. This study investigated the physical properties of wood fiber produced from Norway spruce (Picea abies (L.) H. Karst.) and peat:wood fiber substrate blends as well as the performance of the wood fiber in comparison to the industry standards, i.e., peat and coconut coir in the cultivation of hydroponic strawberry. Tray plants of the June-bearing strawberry (Fragaria × ananassa Duch.) cultivar ‘Malling Centenary’ were transplanted into five different growing media: a peat (80%) and perlite (20%) mixture, stand-alone (100%) coconut coir and three stand-alone (100%) Norway spruce wood fiber substrates (including coarse textured fibers with compact and loose packing density and compacted fine-textured fibers). Ripe strawberries were harvested and registered throughout the production season. The overall marketable yield was comparable across all the tested growing media; however, after 4 weeks of harvest, both coarse wood fiber and fine wood fiber showed better fruiting performance than the peat-perlite mixture. A trend for earlier berry maturation was observed for all wood fiber-based substrates. Plant parameters recorded after the end of production showed that plant height, number of leaves, and biomass production were higher in coarse wood fiber than in the peat-perlite mixture. Moreover, plants grown in wood fiber-based substrates had less unripe berries and flowers not harvested in comparison to both the peat and coir treatments. Full article

Biochar is frequently utilized as a helpful amendment to sustain agricultural productivity. However, it remains uncertain whether biochar can effectively replace chemical fertilizers, especially in karst regions. To investigate the effects of co-applying biochar and chemical fertilizer on the biological characteristics and fertilizer uptake of pod peppers, as well as to determine the optimal ratio of biochar to chemical fertilizers, a two-year field experiment was conducted in southwest China. The results showed that, compared to the locally typical chemical fertilizer treatment (CF), the combined application of biochar and chemical fertilizer significantly increased the yield of both fresh and dry pod pepper. Chemical fertilizer reduction and biochar application also ameliorated fruit quality, increased nutrient accumulation, and improved fertilizer utilization efficiency. What is more, although the employment of biochar made production costs higher, the reduction in chemical fertilizers and the increase in yield improved economic efficiency, especially in the CF₇₀B treatment (70%CF + biochar). In conclusion, moderate amounts of biochar instead of chemical fertilizers may be a valid nutrient management strategy for pod pepper in the karst mountain areas, which is beneficial for maintaining yield stability, improving quality, and increasing net income. Full article