Pub Date : 2024-12-01DOI: 10.1016/j.rhisph.2024.100992
Qingchao Xie , Fanfan Shang , Zhe Zhang , Yihui Liu , Hongmin Zhang , Zheng Han , Yong Zhao
Due to the application of contaminated water irrigation and bio-amendments, the emergence and spread of antibiotic resistance genes (ARGs) and virulence factors (VFs) in soil have become a global problem, thus having potential threats to human health and ecology. However, limited knowledge exists regarding how variations in the soils of Glebionis coronaria L. (previously called Chrysanthemum coronarium L., or the crown daisy) planting sites influence the profiles of ARGs and VFs. In this study, ARGs, VFs, mobile genetic elements (MGEs), and microbial communities were comprehensively characterized using metagenomic methods in the soils from five different Glebionis coronaria L. planting sites in Shanghai. The dominant microbial populations in Glebionis coronaria L. planting soil were not affected by different planting sites, but there were changes in their relative abundance. The abundance and diversity of ARGs, VFs, and MGEs were different among the soils of five planting sites. The overall distribution characteristics of ARGs and VFs in the soils of each planting site remained consistent. Potential hosts shared by ARGs and VFs were present at each site, raising the risk of soil antibiotic resistance. Fe and T were the primary driving factors for the changes in ARGs and VFs, contributing to 11.32 % and 10.74 % of the overall variation in ARGs and VFs, respectively. Taken together, the identification of biological and non-biological factors that affect ARGs and VFs in the soils from different planting sites could provide valuable perspectives for controlling the dissemination of these genes. This study underscored the necessity for accurate and coordinated strategies to tackle the worldwide antibiotic resistance challenge.
{"title":"Metagenomics reveals the profiles and drivers of antibiotic resistance genes and virulence factors in Glebionis coronaria L. planting soil","authors":"Qingchao Xie , Fanfan Shang , Zhe Zhang , Yihui Liu , Hongmin Zhang , Zheng Han , Yong Zhao","doi":"10.1016/j.rhisph.2024.100992","DOIUrl":"10.1016/j.rhisph.2024.100992","url":null,"abstract":"<div><div>Due to the application of contaminated water irrigation and bio-amendments, the emergence and spread of antibiotic resistance genes (ARGs) and virulence factors (VFs) in soil have become a global problem, thus having potential threats to human health and ecology. However, limited knowledge exists regarding how variations in the soils of <em>Glebionis coronaria</em> L. (previously called <em>Chrysanthemum coronarium</em> L., or the crown daisy) planting sites influence the profiles of ARGs and VFs. In this study, ARGs, VFs, mobile genetic elements (MGEs), and microbial communities were comprehensively characterized using metagenomic methods in the soils from five different <em>Glebionis coronaria</em> L. planting sites in Shanghai. The dominant microbial populations in <em>Glebionis coronaria</em> L. planting soil were not affected by different planting sites, but there were changes in their relative abundance. The abundance and diversity of ARGs, VFs, and MGEs were different among the soils of five planting sites. The overall distribution characteristics of ARGs and VFs in the soils of each planting site remained consistent. Potential hosts shared by ARGs and VFs were present at each site, raising the risk of soil antibiotic resistance. Fe and T were the primary driving factors for the changes in ARGs and VFs, contributing to 11.32 % and 10.74 % of the overall variation in ARGs and VFs, respectively. Taken together, the identification of biological and non-biological factors that affect ARGs and VFs in the soils from different planting sites could provide valuable perspectives for controlling the dissemination of these genes. This study underscored the necessity for accurate and coordinated strategies to tackle the worldwide antibiotic resistance challenge.</div></div>","PeriodicalId":48589,"journal":{"name":"Rhizosphere","volume":"32 ","pages":"Article 100992"},"PeriodicalIF":3.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747544","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Clubroot is a soil-borne disease caused by infection with Plasmodiophora brassicae, the causal agent of clubroot, and clubroot can directly cause enormous economic losses in cruciferous crops. The latent spores of P. brassicae are highly active, have a high rate of infection, and are transmitted over a wide range of channels. The manifestation of P. brassicae in fields is often caused by the mixed infection of multiple physiological races, and such mixed infections often pose a substantial challenge to the breeding of plants that are resistant to P. brassicae. In this study, a set of multiple molecular markers for the identification of the main physiological race of P. brassicae was established by utilizing a system to detect the clubroot microspecies-specific primers SCL14 (UP/LP), PBRA_000030-2 (F/R), PBRA_000303-1 (F/R), PBRA_009348-2 (F/R), and Novel342-1 (F/R). The molecular identification of clubroot physiological race resulted in identifying of five such races, including No. 1, 4, 7, 9, and 11. The primers used in this study were more specific, and some strains were not only identified as No. 4 but also as No. 7, such as strains P2, P3, and P4, or as No. 1, such as strain P60. The highest frequency and widest distribution of the small species No. 4 in the sampling site indicated that race No. 4 is the dominant race of P. brassicae. Based on the distribution of race in the sampling site, it was found that the isolated strains of P. brassicae were more differentiated and caused more types of disease. In this study, the primers obtained for the molecular identification of P. brassicae in previous studies were improved and combined to form a multi-molecular marker method to identify the physiological race isolates of P. brassicae, which will provide a theoretical basis to identify the isolates of P. brassicae using molecular markers.
{"title":"Primer pairs to identify physiological races of Plasmodiophora brassicae","authors":"Hui Zhao (赵辉) , Hai-di Liang (梁海迪) , Hu Zhou (周瑚) , Bing-ying Ling (凌丙英) , Erming Liu (刘二明) , Zuo-hua Ren (任佐华)","doi":"10.1016/j.rhisph.2024.100983","DOIUrl":"10.1016/j.rhisph.2024.100983","url":null,"abstract":"<div><div>Clubroot is a soil-borne disease caused by infection with <em>Plasmodiophora brassicae</em>, the causal agent of clubroot, and clubroot can directly cause enormous economic losses in cruciferous crops. The latent spores of <em>P. brassicae</em> are highly active, have a high rate of infection, and are transmitted over a wide range of channels. The manifestation of <em>P. brassicae</em> in fields is often caused by the mixed infection of multiple physiological races, and such mixed infections often pose a substantial challenge to the breeding of plants that are resistant to <em>P. brassicae</em>. In this study, a set of multiple molecular markers for the identification of the main physiological race of <em>P. brassicae</em> was established by utilizing a system to detect the clubroot microspecies-specific primers <em>SCL14 (UP/LP)</em>, <em>PBRA_000030-2 (F/R)</em>, <em>PBRA_000303-1 (F/R)</em>, <em>PBRA_009348-2 (F/R)</em>, and <em>Novel342-1 (F/R)</em>. The molecular identification of clubroot physiological race resulted in identifying of five such races, including No. 1, 4, 7, 9, and 11. The primers used in this study were more specific, and some strains were not only identified as No. 4 but also as No. 7, such as strains P2, P3, and P4, or as No. 1, such as strain P60. The highest frequency and widest distribution of the small species No. 4 in the sampling site indicated that race No. 4 is the dominant race of <em>P. brassicae</em>. Based on the distribution of race in the sampling site, it was found that the isolated strains of <em>P. brassicae</em> were more differentiated and caused more types of disease. In this study, the primers obtained for the molecular identification of <em>P. brassicae</em> in previous studies were improved and combined to form a multi-molecular marker method to identify the physiological race isolates of <em>P. brassicae</em>, which will provide a theoretical basis to identify the isolates of P. brassicae using molecular markers.</div></div>","PeriodicalId":48589,"journal":{"name":"Rhizosphere","volume":"32 ","pages":"Article 100983"},"PeriodicalIF":3.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-01DOI: 10.1016/j.rhisph.2024.100997
Abubakar Dar , Umme Habiba , Muhammad Tauseef Jaffar , Maqshoof Ahmad , Azhar Hussain , Umar Farooq , Sajid Mehmood Nadeem , Muhammad Zahid Mumtaz , Usman Zulfiqar , Abd El-Zaher M.A. Mustafa , Mohamed S. Elshikh
Although the environmental and health challenges associated with conventional herbicide use are well-documented, studies comparing the potential of microbial and plant allelopathy for weed management remain limited. This study aims to fill this gap by evaluating the combined and individual impacts of Pseudomonas fulva T19 and sunflower extract on suppressing the weed canary grass (Phalaris minor Retz.) in wheat, offering a potential eco-friendly alternative to chemical herbicides. The experiment includes 10 treatments: 1) control, 2) sunflower soil incorporation 1% (1% SSI), 3) sunflower extract 2.5% (2.5% SE), 4) sunflower extract 5% (5% SE), 5) sunflower extract 10% (10% SE), 6) T19 bacterial strain (AB), 7) 1% SSI + AB, 8) 2.5% SE + AB, 9) 5% SE + AB, and 10) 10% SE + AB. Applying AB and SE significantly (p ≤ 0.05) suppressed the P. minor and promoted wheat's biochemical properties, growth, and yield. Specifically, AB + 10% SE notably promoted wheat root and shoot lengths (46.6 and18.1%) and their biomasses (38.5 and 30.1%) as compared to the control. Moreover the similar treatment also promoted chlorophyll ‘a’ and ‘b’ contents (32.8 and 28.7%), antioxidant enzymes (APX by 40.4%, CAT by 45.6% and POD by 40.2%), and grain yield per pot by 21.7% by causing the reduction in such characteristics of P. minor. Principal component analysis revealed a negative correlation between wheat and P. minor attributes under the influence of AB and SE allelopathy. Pearson correlation indicated positive correlations among wheat attributes and negative ones with P. minor. Ultimately, combining AB with SE synergistically enhanced wheat growth and yield by suppressing P. minor, suggesting a sustainable alternative to herbicides.
{"title":"Suppression of canary grass (Phalaris minor) with simultaneous use of rhizobacteria and sunflower allelopathy","authors":"Abubakar Dar , Umme Habiba , Muhammad Tauseef Jaffar , Maqshoof Ahmad , Azhar Hussain , Umar Farooq , Sajid Mehmood Nadeem , Muhammad Zahid Mumtaz , Usman Zulfiqar , Abd El-Zaher M.A. Mustafa , Mohamed S. Elshikh","doi":"10.1016/j.rhisph.2024.100997","DOIUrl":"10.1016/j.rhisph.2024.100997","url":null,"abstract":"<div><div>Although the environmental and health challenges associated with conventional herbicide use are well-documented, studies comparing the potential of microbial and plant allelopathy for weed management remain limited. This study aims to fill this gap by evaluating the combined and individual impacts of <em>Pseudomonas fulva</em> T19 and sunflower extract on suppressing the weed canary grass (<em>Phalaris minor</em> Retz.) in wheat, offering a potential eco-friendly alternative to chemical herbicides. The experiment includes 10 treatments: 1) control, 2) sunflower soil incorporation 1% (1% SSI), 3) sunflower extract 2.5% (2.5% SE), 4) sunflower extract 5% (5% SE), 5) sunflower extract 10% (10% SE), 6) T19 bacterial strain (AB), 7) 1% SSI + AB, 8) 2.5% SE + AB, 9) 5% SE + AB, and 10) 10% SE + AB. Applying AB and SE significantly (<em>p</em> ≤ 0.05) suppressed the <em>P. minor</em> and promoted wheat's biochemical properties, growth, and yield. Specifically, AB + 10% SE notably promoted wheat root and shoot lengths (46.6 and18.1%) and their biomasses (38.5 and 30.1%) as compared to the control. Moreover the similar treatment also promoted chlorophyll ‘a’ and ‘b’ contents (32.8 and 28.7%), antioxidant enzymes (APX by 40.4%, CAT by 45.6% and POD by 40.2%), and grain yield per pot by 21.7% by causing the reduction in such characteristics of <em>P. minor</em>. Principal component analysis revealed a negative correlation between wheat and <em>P. minor</em> attributes under the influence of AB and SE allelopathy. Pearson correlation indicated positive correlations among wheat attributes and negative ones with <em>P. minor</em>. Ultimately, combining AB with SE synergistically enhanced wheat growth and yield by suppressing <em>P. minor</em>, suggesting a sustainable alternative to herbicides.</div></div>","PeriodicalId":48589,"journal":{"name":"Rhizosphere","volume":"32 ","pages":"Article 100997"},"PeriodicalIF":3.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142757670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-01DOI: 10.1016/j.rhisph.2024.100993
Xisheng Tai , Ruiqi Yang , Jun Li , Ang Li , Wei Chen , Jiajia Ding
In the cold and arid mining areas of Northwest China, Halogeton glomeratus C. Meyer (Amaranthaceae) is a promising plant for the remediation of heavy metal pollution. In this study, samples correspond to a gradient of nickel and copper pollution, and this study aims to analyze the characteristics of endophytic bacteria in H. glomeratus under such pollution gradients. Samples of the plant H. glomeratus and their corresponding rhizosphere soil were collected from a smelting area, a mining area, and a control area within the Jinchang mine. In mining and smelting areas, Ni in H. glomeratus rhizosphere soils was 95 and 6 times, and Cu was 40 and 94 times higher than control area. Ni in H. glomeratus from these areas was 27 and 4 times, and Cu was 4.2 and 4.6 times greater than control area. The endophytic bacteria predominantly found in H. glomeratus from nickel-copper mining regions was Sphingomonas pseudosanguinis. Our findings might corroborate the notion that heavy metal stress in the soil can markedly facilitate the migration of an unclassified second most abundant species of Cyanobacteria, residing within the roots of H. glomeratus, to aerial tissues, where the stress from heavy metals was diminished. RDA indicated that the migration and enrichment of nickel and copper into the tissues of H. glomeratus in smelting and mining areas influenced changes in the community structure of endophytic bacteria. Under varying levels of nickel and copper stress, endophytic bacteria underwent alterations in their metabolic characteristics, aiding H. glomeratus in withstanding heavy metal stress through processes such as lipid, nucleotide, and amino acid metabolism, xenobiotics biodegradation and metabolism, protein folding, sorting, and degradation, as well as replication and repair. The identification of plant growth-promoting traits, including the ability to release phosphorus, produce IAA and ACC deaminase, and exhibit tolerance to nickel and copper, among culturable dominant strains, had shown that Pseudomonas oryzihabitans K2l-2-LB and Pseudomonas putida K2r-3-R2A possess significant potential for application. These strains could be effectively utilized as microbial inoculants to promote plant growth during the restoration of vegetation in nickel and copper-contaminated mine sites.
在西北寒冷干旱矿区，苋菜科（Halogeton glomeratus C. Meyer）是一种很有前途的重金属污染修复植物。在本研究中，样品对应于镍和铜污染梯度，本研究旨在分析在该污染梯度下肾小球内生细菌的特征。在金昌矿区的一个冶炼区、一个矿区和一个对照区采集了植物肾小球及其根际土壤样品。矿区和冶炼区根际土壤Ni含量分别是对照区的95倍和6倍，Cu含量分别是对照区的40倍和94倍。这些地区的肾小球螺中Ni分别是对照区的27倍和4倍，Cu分别是对照区的4.2倍和4.6倍。产自镍铜矿区的肾小球内生细菌以假蛇鞘单胞菌为主。我们的研究结果可能证实了这样一个观点，即土壤中的重金属胁迫可以显著促进居住在H. glomeratus根部的未分类的第二丰富蓝藻物种向空气组织的迁移，在那里重金属胁迫减少。RDA表明，镍和铜在冶炼区和矿区的迁移和富集影响了内生细菌群落结构的变化。在不同水平的镍和铜胁迫下，内生细菌的代谢特性发生了变化，通过脂质、核苷酸和氨基酸代谢、外源生物降解和代谢、蛋白质折叠、分选和降解以及复制和修复等过程，帮助肾囊H. glomeratus抵御重金属胁迫。在可培养的优势菌株中，通过对植物生长促进性状的鉴定，包括释放磷、产生IAA和ACC脱氨酶的能力以及对镍和铜的耐受性，表明米氏假单胞菌K2l-2-LB和恶臭假单胞菌K2r-3-R2A具有显著的应用潜力。这些菌株可以作为微生物接种剂，在镍铜污染矿区植被恢复过程中有效地促进植物生长。
{"title":"Endophytic bacteria in Halogeton glomeratus from mining areas are mainly Sphingomonas pseudosanguinis, with a Cyanobacteria moving from roots to leaves to avoid heavy metals","authors":"Xisheng Tai , Ruiqi Yang , Jun Li , Ang Li , Wei Chen , Jiajia Ding","doi":"10.1016/j.rhisph.2024.100993","DOIUrl":"10.1016/j.rhisph.2024.100993","url":null,"abstract":"<div><div>In the cold and arid mining areas of Northwest China, <em>Halogeton glomeratus</em> C. Meyer (Amaranthaceae) is a promising plant for the remediation of heavy metal pollution. In this study, samples correspond to a gradient of nickel and copper pollution, and this study aims to analyze the characteristics of endophytic bacteria in <em>H</em>. <em>glomeratus</em> under such pollution gradients. Samples of the plant <em>H</em>. <em>glomeratus</em> and their corresponding rhizosphere soil were collected from a smelting area, a mining area, and a control area within the Jinchang mine. In mining and smelting areas, Ni in <em>H. glomeratus</em> rhizosphere soils was 95 and 6 times, and Cu was 40 and 94 times higher than control area. Ni in <em>H. glomeratus</em> from these areas was 27 and 4 times, and Cu was 4.2 and 4.6 times greater than control area. The endophytic bacteria predominantly found in <em>H. glomeratus</em> from nickel-copper mining regions was <em>Sphingomonas pseudosanguinis</em>. Our findings might corroborate the notion that heavy metal stress in the soil can markedly facilitate the migration of an unclassified second most abundant species of Cyanobacteria, residing within the roots of <em>H. glomeratus</em>, to aerial tissues, where the stress from heavy metals was diminished. RDA indicated that the migration and enrichment of nickel and copper into the tissues of <em>H. glomeratus</em> in smelting and mining areas influenced changes in the community structure of endophytic bacteria. Under varying levels of nickel and copper stress, endophytic bacteria underwent alterations in their metabolic characteristics, aiding <em>H. glomeratus</em> in withstanding heavy metal stress through processes such as lipid, nucleotide, and amino acid metabolism, xenobiotics biodegradation and metabolism, protein folding, sorting, and degradation, as well as replication and repair. The identification of plant growth-promoting traits, including the ability to release phosphorus, produce IAA and ACC deaminase, and exhibit tolerance to nickel and copper, among culturable dominant strains, had shown that <em>Pseudomonas oryzihabitans</em> K2l-2-LB and <em>Pseudomonas putida</em> K2r-3-R2A possess significant potential for application. These strains could be effectively utilized as microbial inoculants to promote plant growth during the restoration of vegetation in nickel and copper-contaminated mine sites.</div></div>","PeriodicalId":48589,"journal":{"name":"Rhizosphere","volume":"32 ","pages":"Article 100993"},"PeriodicalIF":3.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-01DOI: 10.1016/j.rhisph.2024.100996
Mehmet Aydoğdu , İlker Kurbetli , Sirel Canpolat , Ahmet Öztürk
Macrophomina phaseolina is a soilborne fungus inducing yield losses up to 50% in maize (Zea mays L.), but little is known about its pathogenicity on the root system of maize. This study aimed to examine host (maize) - pathogen (M. phaseolina) interaction by considering root infection of M. phaseolina and four agronomic characteristics (plant height, root dry weight, grain weight and biomass) of maize. In this respect, seven maize varieties that belong to different maize variety groups [dent corn (Zea mays var. indentata), sweet corn (Zea mays var. saccharata), popcorn (Zea mays var. everta) and flint corn (Zea mays var. indurata)] were used as host plants. The experiments were conducted using soil inoculation technique in a greenhouse in two consecutive years. As a result, soil inoculation of M. phaseolina caused distinctive rottings on primary, crown and lateral roots and lower stems of the inoculated plants. M. phaseolina caused reductions, 36.39, 47.06, 49.57 and 47.11%, in plant height, root dry weight, grain weight and biomass of the tested maize varieties, respectively. Mean reductions in all the examined agronomic characteristics of the maize varietes were ranked from the highest to the lowest one as follows: popcorn, sweet corn, flint corn and dent corn, respectively. Disease scores significantly (P < 0.01) and positively correlated with the reductions in the examined agronomic characteristics. Based on the root infections, four reaction types (susceptible, moderately susceptible, resistant and moderately resistant) were detected among the maize variety groups. The results not only contribute to understanding of maize - M. phaseolina interaction but also reveal new knowledge for epidemiology of the pathogen in maize as well. To the best of our knowledge, this is the first study classifying reactions of maize varieties that belong to the different variety groups (dent corn, sweet corn, popcorn and flint corn) to root infection of M. phaseolina.
phaseolina是一种导致玉米产量损失高达50%的土传真菌，但对其对玉米根系的致病性知之甚少。本研究以玉米的4个农艺性状（株高、根干重、粒重和生物量）为指标，综合考虑玉米的根侵染情况，探讨了寄主（玉米）与病原菌（玉米）的相互作用。在这方面，以不同玉米品种群的7个玉米品种[凹痕玉米（Zea mays var. indentata），甜玉米（Zea mays var. saccharata），爆米花（Zea mays var. everta）和燧石玉米（Zea mays var. indurata）]为寄主植物。试验采用土壤接种技术，连续两年在温室内进行。结果表明，土壤接种后，接种植株的初生、冠状、侧根和下茎均发生了不同程度的腐烂。稻瘟病菌对玉米株高、根干重、粒重和生物量的影响分别为36.39%、47.6%、49.57%和47.11%。各玉米品种农艺性状平均降幅由高到低依次为：爆米花玉米、甜玉米、燧石玉米和凹痕玉米。疾病评分显著(P <；0.01)，且与所测农艺性状的降低呈正相关。根据根系侵染情况，玉米品种组检测到4种反应类型（感、中感、抗、中抗）。研究结果不仅有助于了解玉米与菜绿分枝杆菌的相互作用，而且为玉米病原菌的流行病学研究提供了新的知识。据我们所知，这是第一次对不同品种群（凹痕玉米、甜玉米、爆米花和燧石玉米）的玉米品种对菜籽病根侵染的反应进行分类的研究。
{"title":"Host response of maize to root infection of Macrophomina phaseolina varies depending on maize variety groups","authors":"Mehmet Aydoğdu , İlker Kurbetli , Sirel Canpolat , Ahmet Öztürk","doi":"10.1016/j.rhisph.2024.100996","DOIUrl":"10.1016/j.rhisph.2024.100996","url":null,"abstract":"<div><div><em>Macrophomina phaseolina</em> is a soilborne fungus inducing yield losses up to 50% in maize (<em>Zea mays</em> L.), but little is known about its pathogenicity on the root system of maize. This study aimed to examine host (maize) - pathogen (<em>M</em>. <em>phaseolina</em>) interaction by considering root infection of <em>M</em>. <em>phaseolina</em> and four agronomic characteristics (plant height, root dry weight, grain weight and biomass) of maize. In this respect, seven maize varieties that belong to different maize variety groups [dent corn (<em>Zea mays</em> var. <em>indentata</em>), sweet corn (<em>Zea mays</em> var. <em>saccharata</em>), popcorn (<em>Zea mays</em> var. <em>everta</em>) and flint corn (<em>Zea mays</em> var. <em>indurata</em>)] were used as host plants. The experiments were conducted using soil inoculation technique in a greenhouse in two consecutive years. As a result, soil inoculation of <em>M</em>. <em>phaseolina</em> caused distinctive rottings on primary, crown and lateral roots and lower stems of the inoculated plants. <em>M</em>. <em>phaseolina</em> caused reductions, 36.39, 47.06, 49.57 and 47.11%, in plant height, root dry weight, grain weight and biomass of the tested maize varieties, respectively. Mean reductions in all the examined agronomic characteristics of the maize varietes were ranked from the highest to the lowest one as follows: popcorn, sweet corn, flint corn and dent corn, respectively. Disease scores significantly (P < 0.01) and positively correlated with the reductions in the examined agronomic characteristics. Based on the root infections, four reaction types (susceptible, moderately susceptible, resistant and moderately resistant) were detected among the maize variety groups. The results not only contribute to understanding of maize - <em>M</em>. <em>phaseolina</em> interaction but also reveal new knowledge for epidemiology of the pathogen in maize as well. To the best of our knowledge, this is the first study classifying reactions of maize varieties that belong to the different variety groups (dent corn, sweet corn, popcorn and flint corn) to root infection of <em>M</em>. <em>phaseolina</em>.</div></div>","PeriodicalId":48589,"journal":{"name":"Rhizosphere","volume":"32 ","pages":"Article 100996"},"PeriodicalIF":3.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142757603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-23DOI: 10.1016/j.rhisph.2024.100995
Tao Yao , Chongyang Wang , Quan Ren , Meng Liu , Wenxiu Sun , Yi Cao
The root-related microorganisms have good effects of stress resistance and disease resistance, and promote the healthy growth of plants. It is important to understand the characteristics of microbial communities in healthy and infected tobacco roots and rhizosphere soil for controlling tobacco bacterial wilt by using beneficial microorganisms in specific niches. In this study, the soil properties and microbial composition of the rhizosphere soil and roots of healthy and bacterial wilt-diseased tobacco plants were analyzed to evaluate their potential influence on plant health. Soil properties including total carbon and total nitrogen have show significant differences in bacterial wilt-infected tobacco. The microbial community diversity and composition are high related to the occurrence of bacterial wilt. Fungal, bacterial and actinobacterial community varied between two different health systems with the increase/decrease of beneficial microbiomes. Results of community functions of rhizosphere microbiomes have showed the differences in Metabolic pathways. This study clarified the impact of bacterial wilt caused by Ralstonia solanacearum on tobacco root and rhizosphere soil microbial communities, providing a theoretical basis for studying the relationship between rhizosphere-soil microorganisms-plant health, and offering a new perspective for utilizing beneficial microorganisms to defend against pathogen invasion in specific ecological niches.
{"title":"Bacterial wilt alters the microbial community characteristics of tobacco root and rhizosphere soil","authors":"Tao Yao , Chongyang Wang , Quan Ren , Meng Liu , Wenxiu Sun , Yi Cao","doi":"10.1016/j.rhisph.2024.100995","DOIUrl":"10.1016/j.rhisph.2024.100995","url":null,"abstract":"<div><div>The root-related microorganisms have good effects of stress resistance and disease resistance, and promote the healthy growth of plants. It is important to understand the characteristics of microbial communities in healthy and infected tobacco roots and rhizosphere soil for controlling tobacco bacterial wilt by using beneficial microorganisms in specific niches. In this study, the soil properties and microbial composition of the rhizosphere soil and roots of healthy and bacterial wilt-diseased tobacco plants were analyzed to evaluate their potential influence on plant health. Soil properties including total carbon and total nitrogen have show significant differences in bacterial wilt-infected tobacco. The microbial community diversity and composition are high related to the occurrence of bacterial wilt. Fungal, bacterial and actinobacterial community varied between two different health systems with the increase/decrease of beneficial microbiomes. Results of community functions of rhizosphere microbiomes have showed the differences in Metabolic pathways. This study clarified the impact of bacterial wilt caused by <em>Ralstonia solanacearum</em> on tobacco root and rhizosphere soil microbial communities, providing a theoretical basis for studying the relationship between rhizosphere-soil microorganisms-plant health, and offering a new perspective for utilizing beneficial microorganisms to defend against pathogen invasion in specific ecological niches.</div></div>","PeriodicalId":48589,"journal":{"name":"Rhizosphere","volume":"32 ","pages":"Article 100995"},"PeriodicalIF":3.4,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142720257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-23DOI: 10.1016/j.rhisph.2024.100994
Zhijie Qiu , Zhaobei Wang , Shuoye Wang , Jingyi Fei , Zhimiao Qu , Hao Wu , Min Zhao , Hongyan Yang
Root rot caused by Fusarium oxysporum is a major threat to the yield and quality of Panax ginseng. The use of antimicrobial compounds from antagonistic microorganisms is effective in controlling pathogens. Lipids from Mortierella can promote plant growth, but their role in disease resistance is unclear. In this study, we conducted a comprehensive analysis of the lipid components of Mortierella alpina and investigated the disease resistance properties and mechanisms of the total lipids and main component arachidonic acid (ARA). The results demonstrated that total lipids and arachidonic acid (ARA) directly inhibited the growth of F. oxysporum, F. solani, and Aspergillus sp., while promoting beneficial microorganisms such as Pseudomonas geniculate, Bacillus velezensis, and Trichoderma velutinum. These compounds also significantly induced the defense response of ginseng adventitious roots. Pot experiments revealed that total lipids and ARA significantly improved theresistance of ginseng to F. oxysporum root rot. Compared with F. oxysporum treatment alone, lipid addition increased the chlorophyll content, root length, fresh weight, and total saponin content. The increased expression of genes related to the jasmonic acid signaling pathway and relatively high nitrogen levels in the rhizosphere soil indicated increased defense mechanisms. Additionally, lipid addition increased the abundances of beneficial microorganisms such as Lysobacter, Gemmatimonas, Pedobacter, Pseudolabrys, and Mortierella, while decreasing Fusarium abundance. Overall, these findings demonstrate that Mortierella-derived lipids enhance ginseng resistance to root rot by directly inhibiting pathogens, modulating defense signaling pathways, and improving the rhizosphere microenvironment.
由镰孢菌（Fusarium oxysporum）引起的根腐病是三七产量和质量的主要威胁。使用拮抗微生物的抗菌化合物能有效控制病原体。毛蒂菌的脂质可促进植物生长，但其在抗病方面的作用尚不清楚。在这项研究中，我们对毛地黄属植物的脂质成分进行了全面分析，并研究了总脂质和主要成分花生四烯酸（ARA）的抗病特性和机制。结果表明，总脂质和花生四烯酸（ARA）能直接抑制草孢霉、禾谷霉和曲霉的生长，同时促进基因假单胞菌、韦氏芽孢杆菌和绒毛霉等有益微生物的生长。这些化合物还能明显诱导人参不定根的防御反应。盆栽实验表明，总脂和 ARA 能显著提高人参对 F. oxysporum 根腐病的抗性。与单独处理草孢子菌相比，添加脂质可增加叶绿素含量、根长、鲜重和总皂苷含量。茉莉酸信号通路相关基因的表达量增加以及根瘤土壤中相对较高的氮含量表明防御机制增强。此外，脂质的添加还增加了有益微生物的数量，如溶菌酶、金霉素菌、拟杆菌、莫蒂埃拉菌，同时降低了镰刀菌的数量。总之，这些研究结果表明，毛蒂菌衍生的脂质通过直接抑制病原体、调节防御信号通路和改善根圈微环境，增强了人参对根腐病的抗性。
{"title":"Protective role of Mortierella alpina-derived lipids in resisting root rot in Panax ginseng","authors":"Zhijie Qiu , Zhaobei Wang , Shuoye Wang , Jingyi Fei , Zhimiao Qu , Hao Wu , Min Zhao , Hongyan Yang","doi":"10.1016/j.rhisph.2024.100994","DOIUrl":"10.1016/j.rhisph.2024.100994","url":null,"abstract":"<div><div>Root rot caused by <em>Fusarium oxysporum</em> is a major threat to the yield and quality of <em>Panax ginseng</em>. The use of antimicrobial compounds from antagonistic microorganisms is effective in controlling pathogens. Lipids from <em>Mortierella</em> can promote plant growth, but their role in disease resistance is unclear. In this study, we conducted a comprehensive analysis of the lipid components of <em>Mortierella alpina</em> and investigated the disease resistance properties and mechanisms of the total lipids and main component arachidonic acid (ARA). The results demonstrated that total lipids and arachidonic acid (ARA) directly inhibited the growth of <em>F. oxysporum</em>, <em>F. solani</em>, and <em>Aspergillus</em> sp., while promoting beneficial microorganisms such as <em>Pseudomonas geniculate</em>, <em>Bacillus velezensis</em>, and <em>Trichoderma velutinum</em>. These compounds also significantly induced the defense response of ginseng adventitious roots. Pot experiments revealed that total lipids and ARA significantly improved theresistance of ginseng to <em>F. oxysporum</em> root rot. Compared with <em>F. oxysporum</em> treatment alone, lipid addition increased the chlorophyll content, root length, fresh weight, and total saponin content. The increased expression of genes related to the jasmonic acid signaling pathway and relatively high nitrogen levels in the rhizosphere soil indicated increased defense mechanisms. Additionally, lipid addition increased the abundances of beneficial microorganisms such as <em>Lysobacter</em>, <em>Gemmatimonas</em>, <em>Pedobacter</em>, <em>Pseudolabrys</em>, and <em>Mortierella</em>, while decreasing <em>Fusarium</em> abundance. Overall, these findings demonstrate that <em>Mortierella</em>-derived lipids enhance ginseng resistance to root rot by directly inhibiting pathogens, modulating defense signaling pathways, and improving the rhizosphere microenvironment.</div></div>","PeriodicalId":48589,"journal":{"name":"Rhizosphere","volume":"32 ","pages":"Article 100994"},"PeriodicalIF":3.4,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142698583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-12DOI: 10.1016/j.rhisph.2024.100991
Dinda Rista Anis Mufida , Ivan Permana Putra , Abdjad Asih Nawangsih , Ni Putu Ratna Ayu Krishanti , Aris Tri Wahyudi
Fusarium oxysporum, a phytopathogenic fungus responsible for fusarium wilt in more than 120 plant species, is primarily managed using synthetic fungicides, which pose environmental hazards. Therefore, alternative biological control methods are urgently needed. Actinobacteria isolated from maize rhizosphere, which produce β-1.3-glucanase enzymes that degrade fungal cell wall glucans, offer promising potential as biocontrol agents. This study aimed to evaluate glucanase activity, identify genes of actinobacteria, and assess their antifungal activity against F. oxysporum. Actinobacteria demonstrating glucanase production, Streptomyces sp. ARJ 22, Streptomyces tendae ARJ 42, Streptomyces sp. ARJ 44, and Streptomyces sp. ARJ 81, were selected. Streptomyces isolates exhibited activity values ranging from 10.38 to 24.08 U/mg of protein. The presence of the bglS gene, encoding endo-β-1.3-glucanase from glycoside hydrolase family 16, supports the production of glucanase. The amino acid sequence was constructed to 3D structural model. This model exhibited high similarity to endo-β-1.3-glucanase from Nocardiopsis sp. F96. In vitro assays demonstrated that all isolates inhibited hyphal growth of F. oxysporum. Direct inhibition assays showed an average inhibition of 26.18%, whereas the filtrate culture method showed 29.38% inhibition. Enzymes from Streptomyces sp. ARJ 44 was partially purified using acetone, resulting in a specific activity of 46.34 U/mg of protein and a purity increase of up to 1.92-fold. The purified enzyme inhibited the growth of F. oxysporum mycelia by 35.80%. This inhibition was confirmed by observing damage to F. oxysporum hyphae using scanning electron microscopy. The study concluded that the four Streptomyces sp. Strains producing β-1.3-glucanase enzymes have potential as biocontrol agents against F. oxysporum.
{"title":"Glucanase enzyme activity from rhizospheric Streptomyces spp. inhibit growth and damage the cell wall of Fusarium oxysporum","authors":"Dinda Rista Anis Mufida , Ivan Permana Putra , Abdjad Asih Nawangsih , Ni Putu Ratna Ayu Krishanti , Aris Tri Wahyudi","doi":"10.1016/j.rhisph.2024.100991","DOIUrl":"10.1016/j.rhisph.2024.100991","url":null,"abstract":"<div><div><em>Fusarium oxysporum</em>, a phytopathogenic fungus responsible for fusarium wilt in more than 120 plant species, is primarily managed using synthetic fungicides, which pose environmental hazards. Therefore, alternative biological control methods are urgently needed. Actinobacteria isolated from maize rhizosphere, which produce β-1.3-glucanase enzymes that degrade fungal cell wall glucans, offer promising potential as biocontrol agents. This study aimed to evaluate glucanase activity, identify genes of actinobacteria, and assess their antifungal activity against <em>F. oxysporum</em>. Actinobacteria demonstrating glucanase production, <em>Streptomyces</em> sp. ARJ 22, <em>Streptomyces tendae</em> ARJ 42, <em>Streptomyces</em> sp. ARJ 44, and <em>Streptomyces</em> sp. ARJ 81, were selected. <em>Streptomyces</em> isolates exhibited activity values ranging from 10.38 to 24.08 U/mg of protein. The presence of the <em>bgl</em>S gene, encoding endo-β-1.3-glucanase from glycoside hydrolase family 16, supports the production of glucanase. The amino acid sequence was constructed to 3D structural model. This model exhibited high similarity to endo-β-1.3-glucanase from <em>Nocardiopsis</em> sp. F96. <em>In vitro</em> assays demonstrated that all isolates inhibited hyphal growth of <em>F. oxysporum</em>. Direct inhibition assays showed an average inhibition of 26.18%, whereas the filtrate culture method showed 29.38% inhibition. Enzymes from <em>Streptomyces</em> sp. ARJ 44 was partially purified using acetone, resulting in a specific activity of 46.34 U/mg of protein and a purity increase of up to 1.92-fold. The purified enzyme inhibited the growth of <em>F. oxysporum</em> mycelia by 35.80%. This inhibition was confirmed by observing damage to <em>F. oxysporum</em> hyphae using scanning electron microscopy. The study concluded that the four <em>Streptomyces</em> sp. Strains producing β-1.3-glucanase enzymes have potential as biocontrol agents against <em>F. oxysporum</em>.</div></div>","PeriodicalId":48589,"journal":{"name":"Rhizosphere","volume":"32 ","pages":"Article 100991"},"PeriodicalIF":3.4,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142698581","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-09DOI: 10.1016/j.rhisph.2024.100990
Misagh Parhizkar , Mohammad Reza Nasiri
The flow depth is an important hydraulic parameter for calculating other hydraulic parameters of overland flow. There is notable changes in hydraulic parameter when the roots of a plant develop in the topsoil. A power regression equation between soil detachment capacity (Dc) and unit energy of cross section (UEC) was established in soils under Fraxinus excelsior L. species based on the Froude number. For measuring Dc, samples collected from soils under the studied species and subjected to five slopes (from 13.9 to 33.9%) and five water discharges (from 0.39 to 0.77 L m−1 s−1) by a hydraulic flume. Compared with the soil with absence of root, the soil with presence of root had lower Dc. The results showed a strong power relationship between the unit energy of cross section and Dc, suggesting that soil detachment rate in rill erosion can be estimated using this hydraulic parameter (R2 = 0.84). This finding is particularly relevant for hillslopes with slopes from 12% to 31%, where the proposed mathematical model could be applied to predict Dc. Overall, this investigation supports a broader use of native species (such as the european ash Fraxinus excelsior L.), as a useful eco-engineering conservation practice and an alternative technique instead of utilizing artificial and expensive conservation practices.
水流深度是计算陆地流其他水力参数的一个重要水力参数。当植物的根系在表土中生长时，水力参数会发生显著变化。根据弗劳德数，建立了 Fraxinus excelsior L. 树种下土壤的脱离能力（Dc）与横截面单位能量（UEC）之间的幂回归方程。为测量 Dc，从所研究树种下的土壤中采集了样本，并通过水槽对其进行了五次斜坡（从 13.9% 到 33.9%）和五次排水（从 0.39 到 0.77 L m-1 s-1）试验。与无根土壤相比，有根土壤的 Dc 值较低。结果表明，横截面单位能量与 Dc 之间存在很强的幂函数关系，这表明可以利用这一水力参数（R2 = 0.84）来估算碾压侵蚀中的土壤剥离率。这一发现尤其适用于坡度在 12% 到 31% 之间的山坡，在这些山坡上，所提出的数学模型可用于预测 Dc。总之，这项调查支持更广泛地使用本地物种（如欧洲白蜡树），将其作为一种有用的生态工程保护措施和替代技术，而不是使用人工和昂贵的保护措施。
{"title":"Modeling root effects on soil detachment capacity using critical flow depth and unit energy of cross section in soils under Fraxinus excelsior L. species","authors":"Misagh Parhizkar , Mohammad Reza Nasiri","doi":"10.1016/j.rhisph.2024.100990","DOIUrl":"10.1016/j.rhisph.2024.100990","url":null,"abstract":"<div><div>The flow depth is an important hydraulic parameter for calculating other hydraulic parameters of overland flow. There is notable changes in hydraulic parameter when the roots of a plant develop in the topsoil. A power regression equation between soil detachment capacity (D<sub>c</sub>) and unit energy of cross section (UEC) was established in soils under <em>Fraxinus excelsior</em> L. species based on the Froude number. For measuring D<sub>c</sub>, samples collected from soils under the studied species and subjected to five slopes (from 13.9 to 33.9%) and five water discharges (from 0.39 to 0.77 L m<sup>−1</sup> s<sup>−1</sup>) by a hydraulic flume. Compared with the soil with absence of root, the soil with presence of root had lower D<sub>c</sub>. The results showed a strong power relationship between the unit energy of cross section and D<sub>c</sub>, suggesting that soil detachment rate in rill erosion can be estimated using this hydraulic parameter (R<sup>2</sup> = 0.84). This finding is particularly relevant for hillslopes with slopes from 12% to 31%, where the proposed mathematical model could be applied to predict D<sub>c</sub>. Overall, this investigation supports a broader use of native species (such as the european ash <em>Fraxinus excelsior</em> L.), as a useful eco-engineering conservation practice and an alternative technique instead of utilizing artificial and expensive conservation practices.</div></div>","PeriodicalId":48589,"journal":{"name":"Rhizosphere","volume":"32 ","pages":"Article 100990"},"PeriodicalIF":3.4,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mangrove forest is a unique wetland ecosystem that is highly productive and provides an environment for a variety of microorganisms. Endophytic fungi derived from mangrove plants provide the plants with protection from adverse environmental conditions, while also allowing the fungi to produce valuable bioactive compounds. The present study sampled 11 mangrove trees and isolated, screened, and identified the potent endophytic fungi and their bioactive substances showing anti-pathogenic, anti-mutagenic and antioxidant activities, while the endophytes were investigated for their enzymatic potential. In total, 47 endophytic fungi were isolated from the leaves (36) and stems (11) of the host plants and all isolates were tested for antagonistic activities against selected plant pathogens. Based on the results, isolates BgS-04 and BcL-05 had the highest anti-pathogenic activities against Curvularia sp., Fusarium sp., and Colletotrichum sp. Therefore, the ethyl acetate crude extracts from these two fungi were further investigated for their antioxidant and anti-mutagenic activities and their phenolic compound contents, based on phytochemical analysis. Based on the results, the crude extracts of BgS-04 and BcL-05 contained 5.24 and 4.8 mg gallic acid equivalent/g of total phenolic compounds, respectively, and had antioxidant activity (half maximal inhibitory concentration) levels of 7.4 and 4.26 mg/mL, respectively. The preliminary qualitative phytochemical analysis of the fungal crude extracts identified tannins and coumarins. The anti-mutagenic activity levels of BgS-04 and BcL-05 against the mutagenic compounds, Trp-P-1 and DMBA, were determined using the Ames test, which revealed that the crude extracts of BgS-04 and BcL-05 had moderate-to-high antimutagenic potential against TA98 and TA100.
All 47 endophytic isolates were assessed for their potential role in producing extracellular enzyme; they were capable of producing protease (53%), pectinase (28%), amylase (26%) and cellulase (19%) but none of them produced lipase. Among the isolates, RmL-01 derived from the leaves of Rhizophora mucronata had the significantly highest amylase production. Maximum amylase production (141.2 U/mL) was observed at 30 °C, pH 7.0 and 120 h of incubation time. Molecular identification of the isolates BgS-04, BcL-05 and RmL-01 using nuclear ribosomal DNA internal transcribed spacer sequences revealed that they were Pestalotiopsis parva, Collectotrichum perseae, and Aspergillus oryzae, respectively, with high bootstrap support. It was concluded that the distinct groups of mangrove endophytes were potential sources of novel and valuable bio-based compounds with impressive anti-plant pathogen, anti-mutagenic, and antioxidant activities and capable of producing multi-industrial enzyme cocktails that might be important and useful for biotechnological applications.
{"title":"Discovery of pharmaceutical compounds in endophytic fungi from mangrove trees","authors":"Siriluck Iamtham , Anyalak Wachirachaikarn , Kathawut Sopalun , Nongpanga Jarussophon","doi":"10.1016/j.rhisph.2024.100989","DOIUrl":"10.1016/j.rhisph.2024.100989","url":null,"abstract":"<div><div>Mangrove forest is a unique wetland ecosystem that is highly productive and provides an environment for a variety of microorganisms. Endophytic fungi derived from mangrove plants provide the plants with protection from adverse environmental conditions, while also allowing the fungi to produce valuable bioactive compounds. The present study sampled 11 mangrove trees and isolated, screened, and identified the potent endophytic fungi and their bioactive substances showing anti-pathogenic, anti-mutagenic and antioxidant activities, while the endophytes were investigated for their enzymatic potential. In total, 47 endophytic fungi were isolated from the leaves (36) and stems (11) of the host plants and all isolates were tested for antagonistic activities against selected plant pathogens. Based on the results, isolates BgS-04 and BcL-05 had the highest anti-pathogenic activities against <em>Curvularia</em> sp., <em>Fusarium</em> sp., and <em>Colletotrichum</em> sp. Therefore, the ethyl acetate crude extracts from these two fungi were further investigated for their antioxidant and anti-mutagenic activities and their phenolic compound contents, based on phytochemical analysis. Based on the results, the crude extracts of BgS-04 and BcL-05 contained 5.24 and 4.8 mg gallic acid equivalent/g of total phenolic compounds, respectively, and had antioxidant activity (half maximal inhibitory concentration) levels of 7.4 and 4.26 mg/mL, respectively. The preliminary qualitative phytochemical analysis of the fungal crude extracts identified tannins and coumarins. The anti-mutagenic activity levels of BgS-04 and BcL-05 against the mutagenic compounds, Trp-P-1 and DMBA, were determined using the Ames test, which revealed that the crude extracts of BgS-04 and BcL-05 had moderate-to-high antimutagenic potential against TA98 and TA100.</div><div>All 47 endophytic isolates were assessed for their potential role in producing extracellular enzyme; they were capable of producing protease (53%), pectinase (28%), amylase (26%) and cellulase (19%) but none of them produced lipase. Among the isolates, RmL-01 derived from the leaves of <em>Rhizophora mucronata</em> had the significantly highest amylase production. Maximum amylase production (141.2 U/mL) was observed at 30 °C, pH 7.0 and 120 h of incubation time. Molecular identification of the isolates BgS-04, BcL-05 and RmL-01 using nuclear ribosomal DNA internal transcribed spacer sequences revealed that they were <em>Pestalotiopsis parva</em>, <em>Collectotrichum perseae</em>, and <em>Aspergillus oryzae</em>, respectively, with high bootstrap support. It was concluded that the distinct groups of mangrove endophytes were potential sources of novel and valuable bio-based compounds with impressive anti-plant pathogen, anti-mutagenic, and antioxidant activities and capable of producing multi-industrial enzyme cocktails that might be important and useful for biotechnological applications.</div></div>","PeriodicalId":48589,"journal":{"name":"Rhizosphere","volume":"32 ","pages":"Article 100989"},"PeriodicalIF":3.4,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663390","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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