Improving yield and quality of vegetable grown in PAEs-contaminated soils by using novel bioorganic fertilizer

Uptake, translocation, and biotransformation of phthalate acid esters in crop plants: A comprehensive review

Phthalate acid esters (PAEs) are prevalent emerging contaminants in agricultural environments. The uptake of PAEs by crop plants has attracted extensive attention due to the risks posed to human health through transfer in food chains. Despite its importance, the interaction between PAEs and crop plants remains poorly understood. In this critical review, the occurrence of six priority control PAEs in various food crops grown in greenhouses and conventional farms is investigated, with detected concentrations reaching up to mg/kg (dry weight) levels. PAEs enter plants through roots, foliar gas, or foliar particle uptake. After entry, PAEs exhibit acropetal translocation from the root and basipetal translocation from the leaf. PAEs are transformed into various metabolites through hydroxylation, hydrolysis, and oxidation in phase I metabolism and further conjugated with biomolecules such as amino acids or sugars in phase II metabolism. Exposure to PAEs disrupts plant homeostasis and activated antioxidant enzymes to alleviate phytotoxicity. Dietary intake of PAEs-contaminated food crops presents potential risks to human health, particularly from fruit and root vegetables consumed by children, warranting specific attention. Furthermore, current knowledge gaps and future perspectives are proposed. This review provides a comprehensive assessment of the knowledge on the uptake, translocation, and transformation of PAEs in crop plants, emphasizing the need for an integrated investigation into the full life cycle of PAEs in plants to ensure food safety.

Bacillus Bio-Organic Fertilizer Altered Soil Microorganisms and Improved Yield and Quality of Radish (Raphanus sativus L.)

Excessive use of fertilizers will not only cause the enrichment of soil N nutrients, soil secondary salinization, soil acidification, and an imbalance of the soil microbial community structure, but will also lead to the nitrate content of vegetables and the ground water exceeding the standard. The application of bio-organic fertilizer could reduce the amount of mineral fertilizer used. However, the effects of nitrogen reduced with different bio-organic fertilizers on soil chemical properties, microbial community structure, and the yield and quality of radish are not clear. In a field experiment, we designed six fertilization treatments: no fertilization (CK), conventional fertilization (T1), a total nitrogen reduction of 20% (T2), and a total nitrogen reduction of 20% with "No. 1", "Seek" or "Jiajiapei" bio-organic fertilizers. The results showed that nitrogen reduction of 20% with Bacillus bio-organic fertilizer (N1) significantly increased the organic matter, pH, total nitrogen content, and the relative abundance of Bacillus and Streptomyce in the soil compared with T1. RDA analysis showed that the pH, organic matter content, invertase and fluorescein diacetate enzyme activity of the soil were significantly correlated with the soil microbial community structure. In addition, the yield and Vc content in radish were increased with the application of bio-organic fertilizers, while on the contrary, the nitrate and cellulose content were decreased, and the N1 treatment showed the best effect. Moreover, the yield had a significant positive correlation with Bacillus. Overall, nitrogen reduction with bio-organic fertilizers, especially full-effective "No. 1" enriched with Bacillus, could alter the soil microbial community structure and effectively improve soil fertility, which in turn enhanced the yield and quality of radish. An application of Bacillus bio-organic fertilizer was an effective strategy to improve soil quality and vegetable safety.

Distribution of microplastics and phthalic acid esters during dry anaerobic digestion of food waste and potential microbial degradation analysis

Food waste (FW) and its biogas residue were considered as sources of terrestrial microplastics (MPs) and phthalic acid esters (PAEs) contamination. However, there was a lack of research and understanding of the MPs and PAEs pollution problem in FW dry anaerobic digestion process (DADP). The MPs and PAEs in three stages of the DADP with the largest monomer disposal scale in China were identified. At the biogas residue extrusion stage, MPs abundance and PAEs concentration reached the highest values, which were 3.63 ± 0.45 × 103 N·kg-1 and 3.62 ± 0.72 mg·kg-1, respectively. Furthermore, there was a significant positive correlation between MPs and PAEs throughout the process (p < 0.05). Although bacteria and fungi with plastic degradation potential were present in all stages, the contamination problem of MPs and PAEs cannot be completely solved through DADP. This study provides a scientific basis for preventing and controlling the pollution of MPs and PAEs.

Phthalate monoesters accumulation in residential indoor dust and influence factors

Phthalate monoesters (mPAEs) possess biological activity that matches or even exceeds that of their parent compounds, phthalate esters (PAEs), negatively impacting humans. Indoor dust is the main carrier of indoor pollutants. In this study, indoor dust samples were collected from 46 households in Changchun City, Jilin Province, in May 2019, and particulate and flocculent fibrous dust was used as the research target to analyze the concentration and compositional characteristics of mPAEs, primary metabolites of five significant PAEs. The influence of factors such as architectural features and living habits in residential areas on exposure to mPAEs was explored. Ten suspected enzyme genes along with two metabolic pathways with the ability to degrade PAEs were screened using PICRUSt2. The results showed that the total concentrations of the five mPAEs in the indoor dust samples were particulate dust (11.49-78.69 μg/g) and flocculent fibrous dust (21.61-72.63 μg/g), respectively. The molar concentration ratio (RC) of mPAEs to corresponding PAEs significantly differed among chemicals, with MMP/DMP and MEP/DEP sporting the highest RC values. Different bacterial types have shown distinct influences against mPAEs and PAEs. Enzyme function and metabolic pathway abundance had a significant effect on the concentration of some mPAEs, mPAEs are most likely derived from microbial degradation of PAEs.

Efficient remediation of di-(2-ethylhexyl) phthalate and plant-growth promotion with the application of a phosphate-solubilizing compound microbial agent

The ecotoxic endocrine-disrupting chemical di-(2-ethylhexyl) phthalate (DEHP) is ubiquitous in agricultural soil, posing a serious threat to human health. Here, we report efficient soil-borne DEHP degradation and plant growth promotion by a microbial organic fertilizer GK-PPB prepared by combining a recycled garden waste-kitchen waste compost product with ternary compound microbial agent PPB-MA, composed of Penicillium oxalic MB08F, Pseudomonas simiae MB751, and Bacillus tequilensis MB05B. The combination of MB08F and MB751 provided synergistic phosphorus solubilization, and MB05B enhanced the DEHP degradation capacity of MB08F via bioemulsification. Under optimal conditions (25.70 °C and pH 7.62), PPB-MA achieved a 96.81 % degradation percentage for 1000 mg L-1 DEHP within 5 days. The degradation curve followed first-order kinetics with a half-life of 18.24 to 24.76 h. A complete mineralization pathway was constructed after identifying the degradation intermediates of 2H-labeled DEHP. Evaluation in Caenorhabditis elegans N2 showed that PPB-MA eliminated the ecological toxicity of DEHP. A pakchoi (Brassica chinensis L.) pot experiment demonstrated that GK-PPB promoted phosphorus solubilization and plant growth, reduced soil DEHP residue, and decreased DEHP accumulation in pakchoi, suggesting its potential practical utility in environmentally responsible and safe cultivation of vegetables.

Uptake and accumulation of di(2-ethylhexyl) phthalate (DEHP) in a soil-ginseng system and toxicological mechanisms on ginseng (Panax ginseng C.A. Meyer)

Di(2-ethylhexyl) phthalate (DEHP) is regarded as a priority environmental pollutant. This study explored the adsorption and accumulation of DEHP within the ginseng-soil system and the mechanism of DEHP toxicity to ginseng (Panax ginseng C.A. Meyer). Under exposure to 22.10 mg/kg DEHP in soil, DEHP mainly accumulated in ginseng leaves (20.28 mg/kg), stems (4.84 mg/kg) and roots (2.00 mg/kg) after 42 days. The oxidative damage, metabolism, protein express of ginseng were comprehensively measured and analyzed. The results revealed that MDA presented an activation trend in ginseng stems and leaves after 42 days of DEHP exposure, while the opposite trend was observed for POD. Levels of ginsenoside metabolites Rg2, Rg3, Rg5, Rd, Rf and CK decreased in the ginseng rhizosphere exudates under DEHP stress. Further investigations revealed that DEHP disrupts ginsenoside synthesis by inducing glycosyltransferase (GS) and squalene synthase (SS) protein interactions. Molecular docking indicated that DEHP could stably bind to GS and SS by intermolecular forces. These findings provide new information on the ecotoxicological effect of DEHP on ginseng root.

Metal-immobilizing Pseudomonas taiwanensis WRS8 reduces heavy metal accumulation in Coriandrum sativum by changing the metal immobilization-related bacterial population abundances

Metal-immobilizing bacteria play a critical role in metal accumulation in vegetables. However, little is known concerning the mechanisms involved in bacteria-induced reduced metal availability and uptake in vegetables. In this study, the impacts of metal-immobilizing Pseudomonas taiwanensis WRS8 on the plant biomass, Cd and Pb availability and uptake in two coriander (Coriandrum sativum L.) cultivars, and bacterial community structure were investigated in the polluted soil. Strain WRS8 increased the biomass of two coriander cultivars by 25-48% and reduced Cd and Pb contents in the edible tissues by 40-59% and available Cd and Pb contents in the rhizosphere soils by 11.1-15.2%, compared with the controls. Strain WRS8 significantly increased the pH values and relative abundances of the dominant populations of Sphingomonas, Pseudomonas, Gaiellales, Streptomyces, Frankiales, Bradyrhizobium, and Luteimonas, while strain WRS8 significantly decreased the relative abundances of the dominant populations of Gemmatimonadaceae, Nitrospira, Haliangium, Paenibacillus, Massilia, Bryobacter, and Rokubacteriales and the rare bacterial populations of Enterorhabdus, Roseburia, Luteibacter, and Planifilum in the rhizosphere soils, compared with the controls. Significantly negative correlations were observed between the available metal concentrations and the abundances of Pseudomonas, Luteimonas, Frankiales, and Planifilum. These results implied that strain WRS8 could affect the abundances of the dominant and rare bacterial populations involved in metal immobilization, resulting in increased pH values and decreased metal availability and uptake in the vegetables in the contaminated soil.

Preparation and application of biochar from co-pyrolysis of different feedstocks for immobilization of heavy metals in contaminated soil

Co-pyrolysis is a potentially effective method for both biomass waste management and multi-functional biochar-based product design. It involves the thermochemical decomposition of biomass waste under anoxic conditions, which can reduce the cost of disposal and produce biochar with beneficial properties. Herein, this study aimed to investigate the properties and environmental applications of biochar from single- and mixed- feedstocks of wheat straw, rice husk, pig manure, and oyster shell at 450 ℃, respectively. A pot experiment with Chinese cabbage was carried out to compare the effects of biochars with limestone on soil Cd and Pb immobilization at two harvest periods. The results indicated that co-pyrolysis of various biomasses exhibited synthetic effects on promoting the calorific value of syngas and enhancing the quality of produced biochar. The pot experiment revealed a significant promotion on soil pH, soil organic matter, cation exchange capacity, and soluble Ca, which consequently reduced Cd and Pb availability. In contrast with limestone treatment, soil amendment with single biomass-derived and co-pyrolysis-derived (COPB) biochars had a significant positive impact on soil fertility and microbial biomass. Application of COPB at a 0.5% dosage consistently and most effectively enhanced the shoot biomass, increased leaf Vitamin C content but reduced leaf content of nitrate and heavy metals in both harvests. Using COPB for soil remediation would be financially visible due to the enhancement of crop yield. Therefore, this study proposes a strategy for targeted enhancement of the functions of biochar derived from co-pyrolysis of selected biomass waste for soil remediation and agricultural production.

Bioorganic fertilizers improve the adaptability and remediation efficiency of Puccinellia distans in multiple heavy metals-contaminated saline soil by regulating the soil microbial community

Soil salinization and heavy metal (HM) pollution are global environmental problems. Bioorganic fertilizers facilitate phytoremediation, but their roles and microbial mechanisms in natural HM-contaminated saline soils have not been explored. Therefore, greenhouse pot trials were conducted with three treatments: control (CK), manure bioorganic fertilizer (MOF), and lignite bioorganic fertilizer (LOF). The results showed that MOF and LOF significantly increased nutrient uptake, biomass, toxic ion accumulation in Puccinellia distans, soil available nutrients, SOC, and macroaggregates. More biomarkers were enriched in MOF and LOF. Network analysis confirmed that MOF and LOF increased the number of bacterial functional groups and fungal community stability and strengthened their positive association with plants; Bacteria have a more significant effect on phytoremediation. Most biomarkers and keystones play important roles in promoting plant growth and stress resistance in the MOF and LOF treatments. In summary, besides enrichment of soil nutrients, MOF and LOF can also improve the adaptability and phytoremediation efficiency of P. distans by regulating the soil microbial community, with LOF having a greater effect.

Noval bio-organic fertilizer containing Arthrobacter sp. DNS10 alleviates atrazine-induced growth inhibition on soybean by improving atrazine removal and nitrogen accumulation

Herbicide atrazine restricts nutrient accumulation and thus inhibits the growth of sensitive crops. The application of organic fertilizer is a common measure that contributes to modulating abiotic tolerance of crops and providing nutrients, but its advantages in combination with atrazine degrading microorganisms as bio-organic fertilizer to alleviate atrazine stress on sensitive crops and the associated mechanisms are unknown. We investigated the beneficial effects of organic and bio-organic fertilizer (named DNBF10) containing Arthrobacter sp. DNS10 applications on growth, leaf nitrogen accumulation, root surface structure and root physiological properties of soybean seedlings exposed to 20 mg kg^-1 atrazine in soil. Compared with organic fertilizer, bio-organic fertilizer DNBF10 exhibited more reduction in soil atrazine residue and plant atrazine accumulation, as well as alleviation in atrazine-induced root oxidative stress and damaged cells of soybean roots. Transcriptome analysis revealed that DNBF10 application enhanced nitrogen utilization by improving the expression of genes involved in nitrogen metabolism in soybean leaves. Besides, genes expression of cytochrome P450 and ABC transporters involved in atrazine detoxification and transport in soybean leaves were also down-regulated by DNBF10 to diminish phytotoxicity of atrazine to soybean seedlings. These results illustrate the molecular mechanism by which the application of DNBF10 alleviates soybean seedlings growth under atrazine stress, providing a step forward for mitigate the atrazine induced inhibition on soybean seedlings growth through decreasing atrazine residues as well as enhancing damaged root repair and nitrogen accumulation.

Effects of fertilizer application on phthalate ester pollution and the soil microbial community in plastic-shed soil on long-term fertilizer experiment

Due to the use of agricultural film, the pollution of phthalate esters (PAEs) in plastic-shed soils has attracted increasing attention. In this study, we used watermelon as a planting system and investigated the effects of organic fertilizer and chemical fertilizer application on the degradation of PAEs by evaluating soil nutrients and soil bacterial communities in plastic-shed soil. The dibutyl phthalate (DBP) concentration in the organic fertilizer soil was only 58.2% in the zero-fertilization control (CK) soil, but the concentrations of monohexyl phthalate (MEHP) and mono-n-butyl ester (MBP), the metabolites of PAEs, were found to be higher. The concentration of MBP is ten times that of DBP. The results showed that fertilization, especially the application of organic fertilizers, had a significant effect on the degradation of PAEs. There were specific biomarkers in different fertilization treatments. Among the microbiome community, Planifilum had the highest relative abundance in the organic fertilizer (OF) soil, and the highest proportion of Thermodesulfovibrionia was detected in the chemical fertilizer (CF) soil. These biomarkers were significantly correlated with PAEs and their metabolites. The relative abundance of Thermomonosporaceae was significantly positively correlated with DBP. Planifilum and Thermaerobacter, which significantly increased in organic fertilizer soil, showed a significant negative correlation with DBP and a significant positive correlation with MBP. The relative abundances of Planifilum and Geobacillus were elevated in the OF soil and may be able to co-metabolize soil nitrogen and PAEs. PAEs and their metabolites in soils had significant effects on soil microbes, as did the soil nutrients including available phosphorus (AP), alkali-hydrolysable nitrogen (Alkali-N), and organic matter (OM). Our research provides scientific support for the use of fertilizers to reduce PAE contamination but also warns of the potential risks of PAE metabolites.

Effects of phthalate esters on soil microbial community under different planting patterns in Northern China: Case study of Hebei Province

Soil microorganisms are biological factors involved in the farmland environment. The factors that shape soil microbial communities and how these are influenced by geographic location, planting pattern (open-field or greenhouse), and soil organic pollutants (phthalate esters, PAEs) remain poorly understood at large scales. Using 16 S rRNA gene and ITS sequencing, we characterized the soil microbiota in open-field and greenhouse soils in Hebei Province, China, and correlated their structure and composition to geographic location, planting pattern and PAEs. Compared with geographic location, planting pattern is more decisive for shaping soil microbes and has more significant effects on bacteria, and the effects are shaped by the number and types of core OTUs. PAEs participated in the shaping of soil microbial communities by altering the relative abundances of dominant microorganisms in the two planting patterns, and the effects of PAEs with high K_ow were more significant. PAEs have a greater impact on bacteria than fungi in both planting patterns. Bacteria in the greenhouse soil were sensitive to the 9 kinds of PAEs detected, however in the open-field samples, mainly responded to PAEs with high K_ow and rarely respond to PAEs with low K_ow. DEHP and DBP, as two monomers with the highest concentration, have significant effects on dominant genera of microorganisms under both planting patterns, with inhibiting effect on bacteria and significantly promotion on fungi. Our study clarified the factors that have a substantial impact on soil microorganisms at the provincial scale and the mechanisms involved in shaping soil microbial community structure, as well as the significant impact of PAEs on soil microbial dominant microorganisms.

An Insight into Microbial Inoculants for Bioconversion of Waste Biomass into Sustainable "Bio-Organic" Fertilizers: A Bibliometric Analysis and Systematic Literature Review

The plant-microbe holobiont has garnered considerable attention in recent years, highlighting its importance as an ecological unit. Similarly, manipulation of the microbial entities involved in the rhizospheric microbiome for sustainable agriculture has also been in the limelight, generating several commercial bioformulations to enhance crop yield and pest resistance. These bioformulations were termed biofertilizers, with the consistent existence and evolution of different types. However, an emerging area of interest has recently focused on the application of these microorganisms for waste valorization and the production of "bio-organic" fertilizers as a result. In this study, we performed a bibliometric analysis and systematic review of the literature retrieved from Scopus and Web of Science to determine the type of microbial inoculants used for the bioconversion of waste into "bio-organic" fertilizers. The Bacillus, Acidothiobacillus species, cyanobacterial biomass species, Aspergillus sp. and Trichoderma sp. were identified to be consistently used for the recovery of nutrients and bioconversion of wastes used for the promotion of plant growth. Cyanobacterial strains were used predominantly for wastewater treatment, while Bacillus, Acidothiobacillus, and Aspergillus were used on a wide variety of wastes such as sawdust, agricultural waste, poultry bone meal, crustacean shell waste, food waste, and wastewater treatment plant (WWTP) sewage sludge ash. Several bioconversion strategies were observed such as submerged fermentation, solid-state fermentation, aerobic composting, granulation with microbiological activation, and biodegradation. Diverse groups of microorganisms (bacteria and fungi) with different enzymatic functionalities such as chitinolysis, lignocellulolytic, and proteolysis, in addition to their plant growth promoting properties being explored as a consortium for application as an inoculum waste bioconversion to fertilizers. Combining the efficiency of such functional and compatible microbial species for efficient bioconversion as well as higher plant growth and crop yield is an enticing opportunity for "bio-organic" fertilizer research.

Di(2-ethylhexyl) phthalate and dibutyl phthalate have a negative competitive effect on the nitrification of black soil

Di (2-ethylhexyl) phthalate (DEHP) and dibutyl phthalate (DBP) are the most widely used plasticizers for agricultural mulching films and one of the most common organic pollutants in black soil. However, little is known about the effect of these two contaminants on nitrification in black soil. This study investigated the changes of 20 mg/kg DEHP and DBP on the diversity of nitrification microbial communities, the abundance of ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) related genes, and the activities of key enzymes involved in nitrification. During ammonia oxidation, DEHP and DBP had uncompetitive inhibition of urease, reducing the copy number of amoA gene, and microorganisms (Azoarcus, Streptomyces and Caulobacter) would use inorganic nitrogen as a nitrogen source for physiological growth. During nitrite oxidation, the copy number of nxrA gene also reduced, and the relative abundance of chemoautotrophic nitrifying bacteria (Nitrosomonas and Nitrobacter) decreased. Moreover, the path analysis results showed that DEHP and DBP mainly directly or indirectly affect AOB and NOB through three ways. These results help better understand the ecotoxicological effects of DEHP and DBP on AOB and NOB in black soil.

Impact of microplastics on bioaccumulation of heavy metals in rape (Brassica napus L.)

Microplastics have become a global environmental problem due to the ubiquitous existence. The impacts of microplastics on heavy metals behaviors in aquatic environment are widely investigated, however, the impacts of microplastics on bioaccumulation of heavy metals in vegetables in terrestrial environment are seldom investigated. Herein, batch experiments were carried out, the microplastics (0.001%, 0.01%, 0.1%) and heavy metal (50, 100 mg/kg Cu²⁺ or 25, 50 mg/kg Pb²⁺) were single or combined spiked into soil to cultivate rapes (Brassica napus L.) in greenhouse. Copper and lead contents of rapes in MP0.1+Cu100 and MP0.1+Pb50 treatments reached 38.9 mg/kg and 9.4 mg/kg, which were significantly (p < 0.05) higher than those of Cu100 (35.3 mg/kg) and Pb50 (8.7 mg/kg) treatments, respectively. Results showed that microplastics in soil would facilitate heavy metals entering rape plants. In addition, contents of total chlorophyll, soluble sugar, vitamin C, malondialdehyde contents, activities of superoxide dismutase and guaiacol peroxidase, as well as related gene expression were analyzed to investigate the toxic effects of these pollutants (microplastics, Cu, and Pb) to rape plants. Malondialdehyde contents of rapes in MP0.1+Cu50, MP0.1+Cu100, MP0.1+Pb25, and MP0.1+Pb50 treatments reached 0.102 mmol/mg Protein, 0.123 mmol/mg Protein, 0.101 mmol/mg Protein, and 0.119 mmol/mg Protein, which were 1.42, 1.37, 1.46, and 1.45 times of those in Cu50, Cu100, Pb25, and Pb50 treatments, respectively. The changes of malondialdehyde content, activities of superoxide dismutase and guaiacol peroxidase, as well as contents of sugar and vitamin C indicated that microplastics in soil would bring severer damage and deteriorate quality of rape plants. The data in this study indicated that microplastics would increase the bioaccumulation of heavy metals in vegetables and damage to vegetables.

Tissue distribution of phthalates in celery under different cultivation patterns and associated dietary exposure

To investigate tissue distribution, spatial difference, temperature variation, and potential health risks of PAEs in vegetables, celery was used as a model plant. Celery samples were collected from open fields and greenhouses from two provinces in China over four seasons. Celery tissues were analyzed for 16 PAE compounds by gas chromatography-tandem mass spectrometry. The total content of PAEs was 89.0-1130.3 μg kg^-1 dry weight (dw) in stems and 155.0-2730.8 μg kg^-1 dw in leaves. Concentrations of PAEs in celeries showed notable spatial differences (P < 0.05), and the levels in samples from open fields were lower than those in samples from plastic greenhouses. In celeries from greenhouses, higher PAE concentrations were observed for plants grown at high temperatures than in plants grown at low temperatures. Discrepancies in tissue distribution indicated different uptake pathways of PAE contaminants. Risk assessments to humans found that both carcinogenic risks and non-carcinogenic risks of PAEs via celery consumption were at an acceptable level. Further research should consider other exposure pathways of PAEs and pay special attention to reducing PAE contents in vegetables.

Identification of a new Talaromyces strain DYM25 isolated from the Yap Trench as a biocontrol agent against Fusarium wilt of cucumber

Fusarium equiseti is a pathogenic fungus of plant root rot, and there are few studies on the biocontrol strains of plant wilt caused by F. equiseti. Hence, we conducted a screening and antimicrobial characterization study of marine-origin biocontrol fungi from water samples of the Yap Trench. A new Talaromyces strain DYM25 was screened from water samples of the Yap Trench in the western Pacific Ocean, and its potential as a biocontrol agent against Fusarium wilt of cucumber was studied. 18S rRNA and ITS gene sequencing verified that strain DYM25 belongs to the genus Talaromyces. The growth of F. equiseti was inhibited by strain DYM25 through the antibiosis effect. A preliminary test was first conducted to examine the bioactive stability of filtered DYM25 broth against F. equiseti under various conditions, including high temperature, UV light, alkaline environment, and the presence of metal ions, which indicated its potential as a bio-control agent. The results of the pot experiment showed that F. equiseti caused cucumber wilt, which could be mitigated using the fermentation broth of strain DYM25 (52.9 %). On the other hand, the alkaloid chromogenic reaction showed that the alkaloid salts present in the crude n-butanol extracts were most likely the major components that might have an antimicrobial effect. Therefore, Talaromyces sp. DYM25 represents a new species that can be used as a novel biocontrol agent against cucumber wilt.