In yeast,the stress-responsive protein Whi2 interacts with phosphatase Psr1 to form a complex that regulates cell growth,reproduction,infection,and the stress response.However,the roles of Whi2 and Psr1 in Fusarium gr...In yeast,the stress-responsive protein Whi2 interacts with phosphatase Psr1 to form a complex that regulates cell growth,reproduction,infection,and the stress response.However,the roles of Whi2 and Psr1 in Fusarium graminearum remain unclear.In this study,we identified homologous genes of WHI2 and PSR1 in F.graminearum and evaluated their functions by constructing deletion mutants.By comparing the responses of the mutants to different stressors,we found that FgWHI2 and FgPSR1 were involved in responding to osmotic,cell wall and cell membrane stresses,while also affecting the sexual and asexual reproduction in F.graminearum.Our studies demonstrated that FgWHI2 and FgPSR1 regulate the biosynthesis of ergosterol and the transcriptional level of FgCYP51C,which is a CYP51 paralogues unique to Fusarium species.This study also found that the deoxynivalenol(DON)production of FgWHI2 and FgPSR1 deletion mutants was reduced by≥90%and DON production was positively correlated with the transcriptional levels of FgWHI2 and FgPSR1.In addition,we observed that FgWHI2 and FgPSR1 were involved in regulating the sensitivity of F.graminearum to chlorothalonil,fluazinam,azoxystrobin,phenamacril,and oligomycin.This study revealed cross-resistance between chlorothalonil and fluazinam.Meanwhile,chlorothalonil and fluazinam inhibited DON biosynthesis by altering the normal expression of FgWhi2 and FgPsr1.Interestingly,the subcellular localization of FgWhi2 and FgPsr1 was significantly altered after treatment with chlorothalonil and fluazinam,with increased co-localization.Collectively,these findings indicate that FgWHI2 and FgPSR1 play crucial roles in stress response mechanisms,reproductive processes,secondary metabolite synthesis,and fungicide sensitivity in F.graminearum.展开更多
[Objectives]This study was conducted to improve the purification agent combination conditions for QuEChERS and establish a method for detecting the residues of 18 fungicides in animal-derived foods(fish,pork,milk,eggs...[Objectives]This study was conducted to improve the purification agent combination conditions for QuEChERS and establish a method for detecting the residues of 18 fungicides in animal-derived foods(fish,pork,milk,eggs,and pork liver)using high-performance liquid chromatography-triple quadrupole tandem mass spectrometry.[Methods]The samples were extracted with acetonitrile,purified with 885 mg of magnesium sulfate,150 mg of PSA(ethylenediamine-N-propylsilane silica gel),and 15 mg of GCB(graphitized carbon black),and analyzed using ACQUITY UPLC BEH C 18 as the chromatographic column with a mobile phase of acetonitrile-0.1%formic acid aqueous solution.[Results]The 18 fungicides showed good linearity in the range of 5.00–200.00μg/L,with correlation coefficients(R^(2))greater than 0.991.The limit of quantification(LOQ)was 0.01 mg/kg.The average recoveries ranged from 63.7%to 117.5%,and the relative standard deviations(RSDs)were between 0.22%and 6.33%.[Conclusions]This method is simple,rapid,and highly accurate,and provides technical reference for the detection and risk assessment of fungicides in animal-derived foods.展开更多
Azole fungicides(AFs)play an important role in the prevention and treatment of fungal diseases in agricultural crops.However,limited studies are addressing the fate and ecological risk of AFs in the urban water cycle ...Azole fungicides(AFs)play an important role in the prevention and treatment of fungal diseases in agricultural crops.However,limited studies are addressing the fate and ecological risk of AFs in the urban water cycle at a large watershed scale.To address this gap,we investigated the spatiotemporal distribution and ecological risk of twenty AFs in the lower reaches of the Yangtze River across four seasons.Carbendazim(CBA),tebuconazole(TBA),tricyclazole(TCA),and propiconazole(PPA)were found to be the dominant compounds.Their highest concentrations were measured in January(188.3 ng/L),and November(2197.1 ng/L),July(162.0 ng/L),and November(1801.9 ng/L),respectively.The comparison between wastewater treatment plants(WWTPs)effluents and surface water suggested that industrial WWTPs are major sources of AFs in the Yangtze River.In particular,TBA and PPA were found to be the most recalcitrant AFs in industrial WWTPs,while difenoconazole(DFA)was found to be the most potent pollutant in municipal WWTPs,with an average removal rate of less than60%.The average risk quotient(RQ)for the entire AFs was 6.45 in the fall,which was higher than in January(0.98),April(0.61),and July(0.40).This indicates that AFs in surface water posed higher environmental risks during the dry season.Additionally,the exposure risk of AFs via drinking water for sensitive populations deserves more attention.This study provides benchmark data on the occurrence of AFs in the lower reaches of the Yangtze River,and offers suggestions for better reduction of AFs.展开更多
[Objective] This study was conducted to determine the toxicity of 26 fungicides against Oidium heveae and the synergistic effects of their binary mixtures.[Method] The sensitivity of O.heveae to 26 fungicides was dete...[Objective] This study was conducted to determine the toxicity of 26 fungicides against Oidium heveae and the synergistic effects of their binary mixtures.[Method] The sensitivity of O.heveae to 26 fungicides was determined in vitro and in vivo by calculating EC50 values.Horsfall＇s toxicity rate was preliminarily employed to predict the type of joint action of 180 two-way mixtures,based on which the interaction level of the potentially synergistic mixtures was validated by Sun and Johnson＇s co-toxicity coefficient.[Result] Triflumizole,pyraoxystrobin,flufenoxystrobin,epoxiconazole,pyrametostrobin,flusilazole,pyraclostrobin and tetraconazole were the most potent inhibitors of both spore germination and mycelial growth.An ‘in vitro-in vivo＇ integrated strategy is proposed for screening the inhibitors of O.heveae,according to the fact that data obtained in germination experiment are able to reflect to some extent the effectiveness of fungicide confirmed by pot experiment.Results achieved by Horsfall＇s were in line with that validated by Sun and Johnson＇s,the Horsfall＇s seems to be a convenient means to assess rapidly the potential interaction type and level of fungicides in a binary mixture.Nineteen mixtures interact synergistically：epoxiconazole ＋ pyraclostrobin at the mixing ratio of 6：4,8：2;tetraconazole ＋ flufenoxystrobin at 1：9,2：8,3：7 and 4：6;triadimefon ＋ flufenoxystrobin at 9：1;triflumizole ＋ flufenoxystrobin at 8：2;flusilazole ＋pyrametostrobin at 7：3,8：2 and 9：1;tetraconazole ＋ pyrametostrobin at 6：4;triadimefon ＋ pyrametostrobin at 5：5,8：2;triflumizole ＋ pyrametostrobin at 7：3,8：2;tetraconazole ＋ pyraoxystrobin at 9：1;triflumizole ＋ pyraoxystrobin at 8：2,9：1.[Conclusion] The single fungicides and their binary mixtures are expected to serve as the alternatives to triadimefon and the alternate use of them could delay the buildup of resistant O.heveae isolate.展开更多
Fungicides are an indispensable tool in plant disease control.Various modes of action(MOAs)have been identified in different fungicides to suppress plant pathogens.The combined use of fungicides with distinct MOAs has...Fungicides are an indispensable tool in plant disease control.Various modes of action(MOAs)have been identified in different fungicides to suppress plant pathogens.The combined use of fungicides with distinct MOAs has been recommended to prevent the development of pathogen resistance.In studying MOAs,metabolomics has been proven to be a robust and high-throughput method.Because metabolites are unique and distinct depending on the biological activities of an organism,MOAs can be identified and classified by establishing metabolic fingerprinting and metabolic profiles.Similarly,if fungicide resistance is developed in a pathogen,the metabolome will change,which can be identified.In this review,we have discussed the principles and advanced applications of metabolomics in the study of MOAs and resistance mechanisms of fungicides,and the potential of metabolic data in understanding the interaction between fungicides and pathogens.Challenges are also discussed in the application of metabolomics,improvement of the study on the mechanism of fungicides in their functions against pathogens and advancing the development of novel fungicides.展开更多
[Objective] The aim was to study the effect of three new fungicides against rice sheath blight in field experiment. [Methods] The experiment set up 7 treatments with three times of repetition and designed by random gr...[Objective] The aim was to study the effect of three new fungicides against rice sheath blight in field experiment. [Methods] The experiment set up 7 treatments with three times of repetition and designed by random grouping. By using 5 sampling points in each plot, and investigating continuous 4 holes of each point, total plants, diseased plants and disease degrees were recorded. Then disease index and control efficiency were calculated, and variance analysis was carried out. [Results] 300 or 450 ml/hm^2 azoxystrobin ＋ difenoconazole 325 g/L SC had better control efficiency to rice sheath blight and had no phytotoxicity effect, we should use it at the initial disease stage and continuously spray 2-3 times. [Conclusion] The experiment provided a theoretical basis for controlling rice sheath blight using fungicides.展开更多
[Objective] This study aims to screen for the high effective fungicides which could significantly decrease the disease incidence and disease index of rice false smut. [Method] The inhibitory activities of the fungicid...[Objective] This study aims to screen for the high effective fungicides which could significantly decrease the disease incidence and disease index of rice false smut. [Method] The inhibitory activities of the fungicide against mycelial growth of Ustilaginoidea virens were measured to in vitro evaluate the ECho values. And 17 fungicides were sprayed to evaluate the efficacy and effect of the fungicides tested in the field trials on the rice characters, [Result] The results showed that epoxicona- zole, difenoconazole, propiconazole and procloraz exhibited high inhibitory activity against mycelial growth of Ustilaginoidea virens with the ECso values 0.04, 0.07, 0.12 and 0.11 pg/ml, respectively. The results of field trials showed that the efficacy of Wen- quning, and fungicides such as difenoconazole, prochloraz, propiconazole, epoxi- conazole and their mixtures in controlling rice false smut were all 70% or more. [Conclusion] The 17 tested fungicides behaved efficacy in controlling rice false smut and did not cause drug injury on leaves and grains of rice plants, sprayed when flag leaves of rice fully expanded.展开更多
In this research,the inhibitory effect of 16 fungicides on Colletotrichum horri causing persimmon anthracnose was investigated using mycelial growth method and spore germination method. The results showed that among t...In this research,the inhibitory effect of 16 fungicides on Colletotrichum horri causing persimmon anthracnose was investigated using mycelial growth method and spore germination method. The results showed that among the 16 tested fungicides,10% of Difenoconazole WG,33. 5% of Copper quinolate SC,25%of Bromothalonil EC,70% of Mancozeb WP,430 g/L of Tebuconazole SC,50% of Prochloraz-manganese chloride and 400 g/L of Flusilazole EC achieved the best inhibitory effect on mycelial growth of C. horri,with the inhibition rate of 100%; 70% of Polyram WG,33. 5% of Copper quinolate SC,25% of Bromothalonil EC,70% of Mancozeb WP,50% of Chlorobromoisocyanuric acid AF,50% of Triram WP and 400 g/L of Flusilazole achieved the best inhibitory effect on spore germination of C. horri,with the germination rate of 0. In conclusion,33. 5% of Copper quinolate SC,25% of Bromothalonil EC,70% of Mancozeb WP and 400 g/L of Flusilazole EC achieved the best inhibitory effect both in mycelial growth and spore germination,which could be used as the preference fungicides for the control of persimmon anthracnose,and 70% of Polyram WG and 50% of Triram WP achieved the secondly best inhibitory effect,which could be used as alternative fungicides. The results of this research could provide scientific evidence for the effective control of persimmon anthracnose,and more optional pesticides for utilization in the production practice of persimmon industry.展开更多
[Objective] This study aimed to screen effective fungicide for prevention and control of apple powdery mildew. [Method] Field efficacy of six kinds of fungi- cides with 18 concentrations against apple powdery mildew w...[Objective] This study aimed to screen effective fungicide for prevention and control of apple powdery mildew. [Method] Field efficacy of six kinds of fungi- cides with 18 concentrations against apple powdery mildew was investigated. [Re- sult] 4 000-fold triflumizole WP exhibited the highest control efficacy of 82.96%, fol- lowed by 3 000-fold triflumizole WP with control efficacy of 77.75%, while 800-fold and 1 000-fold 70% thiophanate methyl WP exhibited relatively low control efficacy, which was both lower than 60%. [Conclusion] In actual production, 4 000-fold triflu- mizole WP and 3 000-fold triflumizole WP should be used alternately to control and prevent apple powdery mildew.展开更多
For exploring the influences of application and residue of chemical fungi- cides on chlamydospore preparations of Trichoderma spp., the effects of seven chemical fungicides on chlamydospore germination and mycelia gro...For exploring the influences of application and residue of chemical fungi- cides on chlamydospore preparations of Trichoderma spp., the effects of seven chemical fungicides on chlamydospore germination and mycelia growth of two bio- control fungi T. harzianum 610 and T. Iongibrachiatum 758 were studied. Carben- dazim, tebuconazole and difenoconazole showed strong toxicities, thiram and car- bexin showed moderate toxicities, and metalaxyl showed Mycelia growth of the two strains was more sensitive to most tested fungicides than those of chlamydospore germination. Chlamydospore germination of 610 was more sensitive to tested fungicides than those of 758, and mycelia growth of 758 was more sensitive to most tested fungi- cides than those of 610. Among the seven fungicides, 98% carbendazim had the strongest effects （ECru values were 1.64 and 0.05μpg/ml）, and 70% pentachloroni- trobenzene had the weakest effects （EC50 values were 1.64 and 0,05 μg/ml） for chlamydospore germination and mycelia growth of 610. As for 758, 98% carbendaz- im had the strongest inhibitory effects and 95% metalaxyl had the weakest inhibitory for chlamydospore germination of 756 （EC50 values were 0.62 and 1 108.61 μg/ml respectively）, whereas 96.2% tebuconazole showed the strongest inhibitory effects for mycelia growth of 758 （EC= value was 0.32μg/ml）, and 95% metalaxyl was the weakest （EC= value was 1 206.29 μg/ml）. According to the applied concentration of different fungicides in practice, we concluded that chlamydospore preparations of 610 and 758 could not be combined with carbendazim, tebuconazole, thiram and carboxin for controlling plant diseases, and the pesticide residues to the biocontrol effects should be kept in mind. Chlamydospore preparations of 610 and 758 can be and difenoconazole for controlling plant dis- eases, 758 chlamydospore preparations and germinated chlamydospore of 610 can be combined with metalaxyl for controlling plant diseases, and pesticide residue risk was not serious.展开更多
The effects of biofungicide formula containing the biocontrol agent Trichoderma harzianum (Jn14) as wettable powder in combination with the fungicides pyrimethanil and a mixture of cyprodinil and flydioxonil on Botryt...The effects of biofungicide formula containing the biocontrol agent Trichoderma harzianum (Jn14) as wettable powder in combination with the fungicides pyrimethanil and a mixture of cyprodinil and flydioxonil on Botrytis cinerea of strawberry in vitro, in vivo and in greenhouse were studied. The pathogen B. cinerea was more affected in vitro by low concentrations of the fungicides tested above 0.4 μg·ml-1 than the bioagent T. harzianum (Jn14). The later was almost insensitive to pyrimethanil. In the same direction, gray mould disease severity on strawberry detached leaves and whole plants was reduced up to 89% by the tested fungicides, compared to the control, while the application of T. harzianum (Jn14) alone reduced disease severity up to 45% on strawberry detached leaves, compared to the control. In the integrated control approach, the combination of T. harzianum (Jn14) with higher concentrations of the tested fungicides (ED50) completely inhibited strawberry gray mould disease severity in pots and the greenhouse.展开更多
[Objective] This study was conducted to screen suitable fungicides to con-trol ginseng leaf blight caused by Alternaria panax_Whetz. [Method] The antifungal activity of seven fungicides against A. panax_ was determine...[Objective] This study was conducted to screen suitable fungicides to con-trol ginseng leaf blight caused by Alternaria panax_Whetz. [Method] The antifungal activity of seven fungicides against A. panax_ was determined based on mycelial growth rate in vitro. [Result] The results of in vitro antibiotic activity assay showed that there were significant differences in inhibition rate among different concentration treatments of each of the seven fungicides. Toxicity test results showed that among the seven fungicides, difenoconazole had the smal est EC50 （0.61 mg/L）, fol owed by streptomycin and captan, with EC50 value lower than 100 mg/L. [Conclusion] A fungicide which had strong antifungal activity on A. panax was screened out, and the results wil provide a theoretical basis for further field trial.展开更多
Widespread use of azole fungicides and low removal efficiency in wastewater treatment plants(WWTPs) have led to the elevated concentration of azole fungicides in receiving environment. However, there was limited resea...Widespread use of azole fungicides and low removal efficiency in wastewater treatment plants(WWTPs) have led to the elevated concentration of azole fungicides in receiving environment. However, there was limited research about the removal mechanism of azole fungicides in the biological treatment of WWTPs. Imidazole fungicide climbazole and triazole fungicide fluconazole were selected to investigate the biodegradation mechanism of azole fungicides in activated sludge under aerobic conditions. Climbazole was found to be adsorbed to solid sludge and resulted in quick biodegradation. The degradation of climbazole in the aerobic activated sludge system was fitted well by the first-order kinetic model with a half-life of 5.3 days, while fluconazole tended to stay in liquid and had only about 30% of loss within 77 days incubation. Ten biotransformation products of climbazole were identified by high resolution mass spectrometry using suspect and non-target screening method. But no biodegradation products of fluconazole were identified due to its limited removal. The possible biodegradation pathways for climbazole were proposed based on the products identification and pathway prediction system, and involves oxidative dehalogenation, side chain oxidation and azole ring loss. The findings from this study suggest that it should be a concern for the persistence of fluconazole in the environment.展开更多
Fusarium head blight(FHB) caused by Fusarium graminearum is a devastating fungal disease on small grain cereal crops,because it reduces yield and quality and causes the mycotoxin contamination to the grain.Dynamins an...Fusarium head blight(FHB) caused by Fusarium graminearum is a devastating fungal disease on small grain cereal crops,because it reduces yield and quality and causes the mycotoxin contamination to the grain.Dynamins and dynamin-related proteins(DRPs) are large GTPase superfamily members,which are typically involved in the budding and division of vesicles in eukaryotic cells,but their roles in Fusarium spp.remain unexplored.Here,we found that FgDnm1,a DRP and homolog to Dnm1 in Saccharomyces cerevisiae,contributes to the normal fungal growth,sexual reproduction and sensitivity to fungicides.In addition,we found FgDnm1 co-localizes with mitochondria and is involved in toxisome formation and deoxynivalenol(DON) production.Several quinone outside inhibitors(QoIs) and succinate dehydrogenase inhibitors(SDHIs) cause fragmentated morphology of mitochondria.Importantly,the deletion of FgDnm1displays filamentous mitochondria and blocks the mitochondrial fragmentation induced by QoIs and SDHIs.Taken together,our studies uncover the effect of mitochondrial dynamics in fungal normal growth and how such events link to fungicides sensitivity and toxisome formation.Thus,we concluded that altered mitochondrial morphology induced by QoIs and SDHIs depends on FgDnm1.展开更多
The yeasts Cryptococcus laurentii, Trichosporon pullulans, Rhodotorula glutinis andTrichosporon sp.were used to investigate their sensitivity to four fungicides anddifferent concentrations of CO2, as well as their ant...The yeasts Cryptococcus laurentii, Trichosporon pullulans, Rhodotorula glutinis andTrichosporon sp.were used to investigate their sensitivity to four fungicides anddifferent concentrations of CO2, as well as their antagonistic ability to Penicilliumexpansumand Alternariaalternata in vitro when applied with fungicide. There were significantdifferences in sensitivity to the fungicides among the different yeasts(P=0.05). R.glutinis was more sensitive to Deccocil, Iprodione and Stroby as compared to otheryeasts. Combination antagonistic yeasts with fungicide could more significantly enhancebiocontrol ability of the yeasts against the pathogenic fungi in vitro(P = 0.05). C.laurentii was the most effective antagonist among the four yeasts and could completelycontrol spore germination of P.expansum and A.alternata when combined with Stroby at theconcentration of 100 L L-1. The yeasts, except R.glutinis, could grow well on nutrientyeast dextrose agar (NYDA) after 8 d incubation even at 20% CO2 concentration at 25℃.Particularly Trichosporon sp. showeda better adaptability to low temperature as comparedto other antagonists.展开更多
The increasing demand for safe food without preservatives or pesticides residues has encouraged several studies on natural products with antifungal activity and low toxicity.In this study,ethanolic extracts from leave...The increasing demand for safe food without preservatives or pesticides residues has encouraged several studies on natural products with antifungal activity and low toxicity.In this study,ethanolic extracts from leaves and fruit residues(peel and seeds)of three Brazilian savanna species(Acrocomia aculeata,Campomanesia adamantium and Caryocar brasiliense)were evaluated against phytopathogenic fungi.Additionally,the most active extract was chemically characterized by ESI-MS and its oral acute toxicity was evaluated.Extracts from C.brasiliense(pequi)peel and leaves were active against Alternaria alternata,Alternaria solani and Venturia pirina with minimal inhibitory concentrations between 350 and 1000 lg/mL.When incorporated in solid media,these extracts extended the lag phase of A.alternata and A.solani and reduced the growth rate of A.solani.Pequi peel extract showed better antifungal activity and their ESI-MS analysis revealed the presence of substances widely reported as antifungal such as gallic acid,quinic acid,ellagic acid,glucogalin and corilagin.The oral acute toxicity was relatively low,being considered safe for use as a potential natural fungicide.展开更多
Wheat blast, caused by a fungal pathogen, <i><span style="font-family:Verdana;">Magnaporthe oryzae Tritichum </span></i><span style="font-family:Verdana;">(</span&g...Wheat blast, caused by a fungal pathogen, <i><span style="font-family:Verdana;">Magnaporthe oryzae Tritichum </span></i><span style="font-family:Verdana;">(</span><i><span style="font-family:Verdana;">MoT</span></i><span style="font-family:Verdana;">) pathotype (wheat isolates), was first reported in Bangladesh among Asian countries in 2016. It is a serious disease of wheat causing yield failures and significant economic losses during epidemic years. Extensive use of persistent synthetic pesticides to control notorious wheat blast imposes enormous threat to human health and environment. In addition, the increasing demand for organic food has stimulated people to look for alternative methods. Nowadays, the need for synthetic chemical-free agricultural practices is gaining importance due to effective in managing crop pests, inexpensive, biodegradable, easily available and have low toxicity to non-target organisms. In order to identify active plants, 12 kinds of methanol extracts obtained from 12 medicinal plants were conducted </span><i><span style="font-family:Verdana;">in vitro</span></i><span style="font-family:Verdana;"> to test the effect against </span><i><span style="font-family:Verdana;">Magnaporthe oryzae Triticum </span></i><span style="font-family:Verdana;">(</span><i><span style="font-family:Verdana;">MoT</span></i><span style="font-family:Verdana;">) pathotype. The remarkable inhibitory activity {(29.6 ± 01.5) mm, (25.1 ± 01.0) mm and (20.0 ± 02.0) mm zone of inhibition)} exhibited by the extracts (5 mg/disk) obtained from </span><i><span style="font-family:Verdana;">Artemisia indica</span></i><span style="font-family:Verdana;"> (Nagdona), </span><i><span style="font-family:Verdana;">Persicaria orientalis</span></i><span style="font-family:Verdana;"> (Bishkatali) and </span><i><span style="font-family:Verdana;">Clerodendrum indicum</span></i><span style="font-family:Verdana;"> (Bamonhati), respectively. Other medicinal plant extracts did not show any significant or no activity at all. Therefore, the three plant extracts might be a promising source for developing natural fungicides against wheat blast.</span>展开更多
The morphophysiological and molecular-genetic parameters of T. caries isolates collected from various fields of Southern Urals agrocenoses have been analysed. Isolate 1 of wheat callus had a high growth rate in vitro ...The morphophysiological and molecular-genetic parameters of T. caries isolates collected from various fields of Southern Urals agrocenoses have been analysed. Isolate 1 of wheat callus had a high growth rate in vitro even in the presence of 0.1 mg/l fungicide Baitan. Isolate 2 of wheat callus had a low growth rate whereas 0.1 mg/l Baitan significantly inhibited its growth. Comparison of nucleotide sequences of 18S RNA gene of the two isolates showed high level of homology between them, but a large number of nucleotide substitutions have been found. The most characteristic excision was five nucleotides at position 461 of the isolate 2, compared with the isolate 1. Our results allow to assume that the environmental stress including high pesticide concentration may cause the resistance of T. caries pathogen to fungicides.展开更多
Konjac （Amorphophallus muelleri）, a genus of tuberous plants in the Araceae family, is one of high-value crops in Southwest China. This study aimed at identifying the main pathogens causing tuber rot during storage ...Konjac （Amorphophallus muelleri）, a genus of tuberous plants in the Araceae family, is one of high-value crops in Southwest China. This study aimed at identifying the main pathogens causing tuber rot during storage ofA. muelleri and screening the effective fungicides, so as to prolong the storage period ofA. muelleri and decrease the losses. Isolation and identification, as well as pathogenicity test and retro-inoculation experiments were made for the pathogen causing tuber rot during storage ofA. muelleri in Kunming city, Yunnan province, China. The effective fungicides for the main pathogens were also screened in the laboratory. Six fungi were identified as the pathogens causing tuber rot of A. muelleri, which were Fusarium solani （Mart,） Sacc., Fusarium oxysporum Schlecht., Botrytis cinerea Pers., Alternaria alternata （Fr.） Keissl., Rhizopus nigricans Ehrenb., Penicillium ulaiense Hsieh, Su ＆ Tzean. The main pathogens causing postharvest diseases ofA. muelleri were F. solani, F. oxysporum and B. cinerea. The isolation frequencies of them were 33.9%, 10.5% and 19.4%, respectively. After artificial inoculation, the incidence of tubers infected by F. solani, F. oxysporum and B. cinerea was 100%, 83% and 95%, respectively. The results of chemical screening showed that, in potato dextrose agar （PDA） media plate, the compounds Fludioxonil （50% WP） and Boscalid （50% WG） were the most effective in controlling the three main pathogens, and the average effect reached more than 97%. The test of fungicidal antisepsis on tubers consisted ofA. muelleri being dipped in the 9,000x diluted solution of Fludioxonil （50% WP） or in the 3,500x diluted solution of Boscalid （50% WG） for 3 min and stored at room temperature （25 ℃） for 7 d and 15 d, respectively. The fungicidal effects of Fludioxonil against F. solani, F. oxysporum and B. cinerea for 7 d and 15 d were 88.6%/83.2%, 90.1%/84.7% and 93.0%/91.5%, respectively, whereas the fungicidal effects of Boscalid were 87.0%/85.3%, 89.0%/85.6% and 89.2%/89.1%, respectively. The results may provide useful information for the control ofpostharvest diseases ofA. muelleri.展开更多
[Objective] The research aimed to isolate and identify the pathogen of anthracnose of Ligusticum chuanxiong Hort,and make the antifungal test on four kinds of fungicides for selecting the optimum fungicides.[Method] T...[Objective] The research aimed to isolate and identify the pathogen of anthracnose of Ligusticum chuanxiong Hort,and make the antifungal test on four kinds of fungicides for selecting the optimum fungicides.[Method] The pathogenic fungi was separated according to Koch＇s rule and the shape characteristics were identified. The antifungal test of fungicides was made by using plate mycelium growth inhibition method.[Result] The pathogenic fungi was separated from leaves of Ligusticum chuanxiong Hort. and morphological characters were consistent with that of Colletotrichum gloeosporioides. In addition to chloroisobromine cyanuric acid,the other three fungicides could inhibit the mycelium growth. The growth inhibition rates of 1 000 times Metalaxyl＋mancozeb,zineb,Thiophanate-methyl for the mycelium were 26.8%,22.1%,59.8% respectively after 7 days.[Conclusion] The anthracnose was caused by Colletotrichum gloeosporioides. Ligusticum chuanxiong Hort. was a new record host plant of Colletotrichum gloeosporioides and the best inhibiting fungicide was Thiophanate methyl.展开更多
基金supported by the National Key Research and Development Program of China(2022YFD1400100)the Jiangsu Agriculture Science and Technology Innovation Fund,China(CX(21)2037)+1 种基金the Guidance Foundation of the Hainan Institute of Nanjing Agricultural University,China(NAUSY-MS03)the Postgraduate Research&Practice Innovation Program of Jiangsu Province,China(KYCX20_0596)。
文摘In yeast,the stress-responsive protein Whi2 interacts with phosphatase Psr1 to form a complex that regulates cell growth,reproduction,infection,and the stress response.However,the roles of Whi2 and Psr1 in Fusarium graminearum remain unclear.In this study,we identified homologous genes of WHI2 and PSR1 in F.graminearum and evaluated their functions by constructing deletion mutants.By comparing the responses of the mutants to different stressors,we found that FgWHI2 and FgPSR1 were involved in responding to osmotic,cell wall and cell membrane stresses,while also affecting the sexual and asexual reproduction in F.graminearum.Our studies demonstrated that FgWHI2 and FgPSR1 regulate the biosynthesis of ergosterol and the transcriptional level of FgCYP51C,which is a CYP51 paralogues unique to Fusarium species.This study also found that the deoxynivalenol(DON)production of FgWHI2 and FgPSR1 deletion mutants was reduced by≥90%and DON production was positively correlated with the transcriptional levels of FgWHI2 and FgPSR1.In addition,we observed that FgWHI2 and FgPSR1 were involved in regulating the sensitivity of F.graminearum to chlorothalonil,fluazinam,azoxystrobin,phenamacril,and oligomycin.This study revealed cross-resistance between chlorothalonil and fluazinam.Meanwhile,chlorothalonil and fluazinam inhibited DON biosynthesis by altering the normal expression of FgWhi2 and FgPsr1.Interestingly,the subcellular localization of FgWhi2 and FgPsr1 was significantly altered after treatment with chlorothalonil and fluazinam,with increased co-localization.Collectively,these findings indicate that FgWHI2 and FgPSR1 play crucial roles in stress response mechanisms,reproductive processes,secondary metabolite synthesis,and fungicide sensitivity in F.graminearum.
基金Supported by Natural Science Foundation of Hunan Province(2024JJ8259).
文摘[Objectives]This study was conducted to improve the purification agent combination conditions for QuEChERS and establish a method for detecting the residues of 18 fungicides in animal-derived foods(fish,pork,milk,eggs,and pork liver)using high-performance liquid chromatography-triple quadrupole tandem mass spectrometry.[Methods]The samples were extracted with acetonitrile,purified with 885 mg of magnesium sulfate,150 mg of PSA(ethylenediamine-N-propylsilane silica gel),and 15 mg of GCB(graphitized carbon black),and analyzed using ACQUITY UPLC BEH C 18 as the chromatographic column with a mobile phase of acetonitrile-0.1%formic acid aqueous solution.[Results]The 18 fungicides showed good linearity in the range of 5.00–200.00μg/L,with correlation coefficients(R^(2))greater than 0.991.The limit of quantification(LOQ)was 0.01 mg/kg.The average recoveries ranged from 63.7%to 117.5%,and the relative standard deviations(RSDs)were between 0.22%and 6.33%.[Conclusions]This method is simple,rapid,and highly accurate,and provides technical reference for the detection and risk assessment of fungicides in animal-derived foods.
基金supported by the National Natural Science Foundation of China(Nos.52270072,4222780043)。
文摘Azole fungicides(AFs)play an important role in the prevention and treatment of fungal diseases in agricultural crops.However,limited studies are addressing the fate and ecological risk of AFs in the urban water cycle at a large watershed scale.To address this gap,we investigated the spatiotemporal distribution and ecological risk of twenty AFs in the lower reaches of the Yangtze River across four seasons.Carbendazim(CBA),tebuconazole(TBA),tricyclazole(TCA),and propiconazole(PPA)were found to be the dominant compounds.Their highest concentrations were measured in January(188.3 ng/L),and November(2197.1 ng/L),July(162.0 ng/L),and November(1801.9 ng/L),respectively.The comparison between wastewater treatment plants(WWTPs)effluents and surface water suggested that industrial WWTPs are major sources of AFs in the Yangtze River.In particular,TBA and PPA were found to be the most recalcitrant AFs in industrial WWTPs,while difenoconazole(DFA)was found to be the most potent pollutant in municipal WWTPs,with an average removal rate of less than60%.The average risk quotient(RQ)for the entire AFs was 6.45 in the fall,which was higher than in January(0.98),April(0.61),and July(0.40).This indicates that AFs in surface water posed higher environmental risks during the dry season.Additionally,the exposure risk of AFs via drinking water for sensitive populations deserves more attention.This study provides benchmark data on the occurrence of AFs in the lower reaches of the Yangtze River,and offers suggestions for better reduction of AFs.
基金financed by the ministry of science and technology of P.R.China
文摘[Objective] This study was conducted to determine the toxicity of 26 fungicides against Oidium heveae and the synergistic effects of their binary mixtures.[Method] The sensitivity of O.heveae to 26 fungicides was determined in vitro and in vivo by calculating EC50 values.Horsfall＇s toxicity rate was preliminarily employed to predict the type of joint action of 180 two-way mixtures,based on which the interaction level of the potentially synergistic mixtures was validated by Sun and Johnson＇s co-toxicity coefficient.[Result] Triflumizole,pyraoxystrobin,flufenoxystrobin,epoxiconazole,pyrametostrobin,flusilazole,pyraclostrobin and tetraconazole were the most potent inhibitors of both spore germination and mycelial growth.An ‘in vitro-in vivo＇ integrated strategy is proposed for screening the inhibitors of O.heveae,according to the fact that data obtained in germination experiment are able to reflect to some extent the effectiveness of fungicide confirmed by pot experiment.Results achieved by Horsfall＇s were in line with that validated by Sun and Johnson＇s,the Horsfall＇s seems to be a convenient means to assess rapidly the potential interaction type and level of fungicides in a binary mixture.Nineteen mixtures interact synergistically：epoxiconazole ＋ pyraclostrobin at the mixing ratio of 6：4,8：2;tetraconazole ＋ flufenoxystrobin at 1：9,2：8,3：7 and 4：6;triadimefon ＋ flufenoxystrobin at 9：1;triflumizole ＋ flufenoxystrobin at 8：2;flusilazole ＋pyrametostrobin at 7：3,8：2 and 9：1;tetraconazole ＋ pyrametostrobin at 6：4;triadimefon ＋ pyrametostrobin at 5：5,8：2;triflumizole ＋ pyrametostrobin at 7：3,8：2;tetraconazole ＋ pyraoxystrobin at 9：1;triflumizole ＋ pyraoxystrobin at 8：2,9：1.[Conclusion] The single fungicides and their binary mixtures are expected to serve as the alternatives to triadimefon and the alternate use of them could delay the buildup of resistant O.heveae isolate.
基金funded by the National Key R&D Program of China(grant no.2022YFD1400900).
文摘Fungicides are an indispensable tool in plant disease control.Various modes of action(MOAs)have been identified in different fungicides to suppress plant pathogens.The combined use of fungicides with distinct MOAs has been recommended to prevent the development of pathogen resistance.In studying MOAs,metabolomics has been proven to be a robust and high-throughput method.Because metabolites are unique and distinct depending on the biological activities of an organism,MOAs can be identified and classified by establishing metabolic fingerprinting and metabolic profiles.Similarly,if fungicide resistance is developed in a pathogen,the metabolome will change,which can be identified.In this review,we have discussed the principles and advanced applications of metabolomics in the study of MOAs and resistance mechanisms of fungicides,and the potential of metabolic data in understanding the interaction between fungicides and pathogens.Challenges are also discussed in the application of metabolomics,improvement of the study on the mechanism of fungicides in their functions against pathogens and advancing the development of novel fungicides.
文摘[Objective] The aim was to study the effect of three new fungicides against rice sheath blight in field experiment. [Methods] The experiment set up 7 treatments with three times of repetition and designed by random grouping. By using 5 sampling points in each plot, and investigating continuous 4 holes of each point, total plants, diseased plants and disease degrees were recorded. Then disease index and control efficiency were calculated, and variance analysis was carried out. [Results] 300 or 450 ml/hm^2 azoxystrobin ＋ difenoconazole 325 g/L SC had better control efficiency to rice sheath blight and had no phytotoxicity effect, we should use it at the initial disease stage and continuously spray 2-3 times. [Conclusion] The experiment provided a theoretical basis for controlling rice sheath blight using fungicides.
基金Supported by Agricultural S&T Innovation:Genetic Structure Analysis and Parasitism Fitness of U.virens in Anhui Province(14B1148)Special Fund for Talent Development:Pesticide Innovation and High-efficient Application Technology(13C1109)~~
文摘[Objective] This study aims to screen for the high effective fungicides which could significantly decrease the disease incidence and disease index of rice false smut. [Method] The inhibitory activities of the fungicide against mycelial growth of Ustilaginoidea virens were measured to in vitro evaluate the ECho values. And 17 fungicides were sprayed to evaluate the efficacy and effect of the fungicides tested in the field trials on the rice characters, [Result] The results showed that epoxicona- zole, difenoconazole, propiconazole and procloraz exhibited high inhibitory activity against mycelial growth of Ustilaginoidea virens with the ECso values 0.04, 0.07, 0.12 and 0.11 pg/ml, respectively. The results of field trials showed that the efficacy of Wen- quning, and fungicides such as difenoconazole, prochloraz, propiconazole, epoxi- conazole and their mixtures in controlling rice false smut were all 70% or more. [Conclusion] The 17 tested fungicides behaved efficacy in controlling rice false smut and did not cause drug injury on leaves and grains of rice plants, sprayed when flag leaves of rice fully expanded.
基金Supported by Key R&D Program of Shandong Province(2018GNC110013)the Innovative Project of Forestry Science and Technology of Shandong Provinc of China(LYCX04-2018-23)Agricultural Improved Seed Project of Shandong Province(2016LZG012)
文摘In this research,the inhibitory effect of 16 fungicides on Colletotrichum horri causing persimmon anthracnose was investigated using mycelial growth method and spore germination method. The results showed that among the 16 tested fungicides,10% of Difenoconazole WG,33. 5% of Copper quinolate SC,25%of Bromothalonil EC,70% of Mancozeb WP,430 g/L of Tebuconazole SC,50% of Prochloraz-manganese chloride and 400 g/L of Flusilazole EC achieved the best inhibitory effect on mycelial growth of C. horri,with the inhibition rate of 100%; 70% of Polyram WG,33. 5% of Copper quinolate SC,25% of Bromothalonil EC,70% of Mancozeb WP,50% of Chlorobromoisocyanuric acid AF,50% of Triram WP and 400 g/L of Flusilazole achieved the best inhibitory effect on spore germination of C. horri,with the germination rate of 0. In conclusion,33. 5% of Copper quinolate SC,25% of Bromothalonil EC,70% of Mancozeb WP and 400 g/L of Flusilazole EC achieved the best inhibitory effect both in mycelial growth and spore germination,which could be used as the preference fungicides for the control of persimmon anthracnose,and 70% of Polyram WG and 50% of Triram WP achieved the secondly best inhibitory effect,which could be used as alternative fungicides. The results of this research could provide scientific evidence for the effective control of persimmon anthracnose,and more optional pesticides for utilization in the production practice of persimmon industry.
基金Supported by Fund of Guizhou Academy of Agricultural Sciences "Study on Pathogenesis and Chemical Control Techniques of Apple Powdery Mildew in Western Guizhou"[QNKH(Fund)No.2010001]Special Project of Guizhou Academy of Agricultural Sciences "Introduction and Demonstration of Apple Three-excellence Technology"[QNKYZX(2009)No.041]~~
文摘[Objective] This study aimed to screen effective fungicide for prevention and control of apple powdery mildew. [Method] Field efficacy of six kinds of fungi- cides with 18 concentrations against apple powdery mildew was investigated. [Re- sult] 4 000-fold triflumizole WP exhibited the highest control efficacy of 82.96%, fol- lowed by 3 000-fold triflumizole WP with control efficacy of 77.75%, while 800-fold and 1 000-fold 70% thiophanate methyl WP exhibited relatively low control efficacy, which was both lower than 60%. [Conclusion] In actual production, 4 000-fold triflu- mizole WP and 3 000-fold triflumizole WP should be used alternately to control and prevent apple powdery mildew.
基金Supported by Special Fund for Agro-scientific Research in the Public Interest(201303057)948 Program(2011-G4)~~
文摘For exploring the influences of application and residue of chemical fungi- cides on chlamydospore preparations of Trichoderma spp., the effects of seven chemical fungicides on chlamydospore germination and mycelia growth of two bio- control fungi T. harzianum 610 and T. Iongibrachiatum 758 were studied. Carben- dazim, tebuconazole and difenoconazole showed strong toxicities, thiram and car- bexin showed moderate toxicities, and metalaxyl showed Mycelia growth of the two strains was more sensitive to most tested fungicides than those of chlamydospore germination. Chlamydospore germination of 610 was more sensitive to tested fungicides than those of 758, and mycelia growth of 758 was more sensitive to most tested fungi- cides than those of 610. Among the seven fungicides, 98% carbendazim had the strongest effects （ECru values were 1.64 and 0.05μpg/ml）, and 70% pentachloroni- trobenzene had the weakest effects （EC50 values were 1.64 and 0,05 μg/ml） for chlamydospore germination and mycelia growth of 610. As for 758, 98% carbendaz- im had the strongest inhibitory effects and 95% metalaxyl had the weakest inhibitory for chlamydospore germination of 756 （EC50 values were 0.62 and 1 108.61 μg/ml respectively）, whereas 96.2% tebuconazole showed the strongest inhibitory effects for mycelia growth of 758 （EC= value was 0.32μg/ml）, and 95% metalaxyl was the weakest （EC= value was 1 206.29 μg/ml）. According to the applied concentration of different fungicides in practice, we concluded that chlamydospore preparations of 610 and 758 could not be combined with carbendazim, tebuconazole, thiram and carboxin for controlling plant diseases, and the pesticide residues to the biocontrol effects should be kept in mind. Chlamydospore preparations of 610 and 758 can be and difenoconazole for controlling plant dis- eases, 758 chlamydospore preparations and germinated chlamydospore of 610 can be combined with metalaxyl for controlling plant diseases, and pesticide residue risk was not serious.
文摘The effects of biofungicide formula containing the biocontrol agent Trichoderma harzianum (Jn14) as wettable powder in combination with the fungicides pyrimethanil and a mixture of cyprodinil and flydioxonil on Botrytis cinerea of strawberry in vitro, in vivo and in greenhouse were studied. The pathogen B. cinerea was more affected in vitro by low concentrations of the fungicides tested above 0.4 μg·ml-1 than the bioagent T. harzianum (Jn14). The later was almost insensitive to pyrimethanil. In the same direction, gray mould disease severity on strawberry detached leaves and whole plants was reduced up to 89% by the tested fungicides, compared to the control, while the application of T. harzianum (Jn14) alone reduced disease severity up to 45% on strawberry detached leaves, compared to the control. In the integrated control approach, the combination of T. harzianum (Jn14) with higher concentrations of the tested fungicides (ED50) completely inhibited strawberry gray mould disease severity in pots and the greenhouse.
基金Supported by National Natural Science Fondation of China(31260067)Collegeenterprise Cooperation Project of Yanbian University[(2015)6]~~
文摘[Objective] This study was conducted to screen suitable fungicides to con-trol ginseng leaf blight caused by Alternaria panax_Whetz. [Method] The antifungal activity of seven fungicides against A. panax_ was determined based on mycelial growth rate in vitro. [Result] The results of in vitro antibiotic activity assay showed that there were significant differences in inhibition rate among different concentration treatments of each of the seven fungicides. Toxicity test results showed that among the seven fungicides, difenoconazole had the smal est EC50 （0.61 mg/L）, fol owed by streptomycin and captan, with EC50 value lower than 100 mg/L. [Conclusion] A fungicide which had strong antifungal activity on A. panax was screened out, and the results wil provide a theoretical basis for further field trial.
基金supported by the National Natural Science Foundation of China(Nos.41473105,41877358 and 21806043)Scientific Research and Technology Development Program of Guangxi(No.2018AB36018)+1 种基金Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety(No.2019B030301008)the Pearl River Talent Plan of Guangdong Province(No.2017GC010244)。
文摘Widespread use of azole fungicides and low removal efficiency in wastewater treatment plants(WWTPs) have led to the elevated concentration of azole fungicides in receiving environment. However, there was limited research about the removal mechanism of azole fungicides in the biological treatment of WWTPs. Imidazole fungicide climbazole and triazole fungicide fluconazole were selected to investigate the biodegradation mechanism of azole fungicides in activated sludge under aerobic conditions. Climbazole was found to be adsorbed to solid sludge and resulted in quick biodegradation. The degradation of climbazole in the aerobic activated sludge system was fitted well by the first-order kinetic model with a half-life of 5.3 days, while fluconazole tended to stay in liquid and had only about 30% of loss within 77 days incubation. Ten biotransformation products of climbazole were identified by high resolution mass spectrometry using suspect and non-target screening method. But no biodegradation products of fluconazole were identified due to its limited removal. The possible biodegradation pathways for climbazole were proposed based on the products identification and pathway prediction system, and involves oxidative dehalogenation, side chain oxidation and azole ring loss. The findings from this study suggest that it should be a concern for the persistence of fluconazole in the environment.
基金supported by the National Natural Science Foundation of China (31772190)the Jiangsu Agriculture Science and Technology Innovation Fund, China (JASTIF) (CX(21)2037)the Postgraduate Research & Practice Innovation Program of Jiangsu Province, China (KYCX21_0631)。
文摘Fusarium head blight(FHB) caused by Fusarium graminearum is a devastating fungal disease on small grain cereal crops,because it reduces yield and quality and causes the mycotoxin contamination to the grain.Dynamins and dynamin-related proteins(DRPs) are large GTPase superfamily members,which are typically involved in the budding and division of vesicles in eukaryotic cells,but their roles in Fusarium spp.remain unexplored.Here,we found that FgDnm1,a DRP and homolog to Dnm1 in Saccharomyces cerevisiae,contributes to the normal fungal growth,sexual reproduction and sensitivity to fungicides.In addition,we found FgDnm1 co-localizes with mitochondria and is involved in toxisome formation and deoxynivalenol(DON) production.Several quinone outside inhibitors(QoIs) and succinate dehydrogenase inhibitors(SDHIs) cause fragmentated morphology of mitochondria.Importantly,the deletion of FgDnm1displays filamentous mitochondria and blocks the mitochondrial fragmentation induced by QoIs and SDHIs.Taken together,our studies uncover the effect of mitochondrial dynamics in fungal normal growth and how such events link to fungicides sensitivity and toxisome formation.Thus,we concluded that altered mitochondrial morphology induced by QoIs and SDHIs depends on FgDnm1.
基金supported by the National Science Fund for Distinguished Young Scholars of China(30225030)the National Natural Science Foundation of China(30170663)the Natural Science Foundation of Beijing(6012005).
文摘The yeasts Cryptococcus laurentii, Trichosporon pullulans, Rhodotorula glutinis andTrichosporon sp.were used to investigate their sensitivity to four fungicides anddifferent concentrations of CO2, as well as their antagonistic ability to Penicilliumexpansumand Alternariaalternata in vitro when applied with fungicide. There were significantdifferences in sensitivity to the fungicides among the different yeasts(P=0.05). R.glutinis was more sensitive to Deccocil, Iprodione and Stroby as compared to otheryeasts. Combination antagonistic yeasts with fungicide could more significantly enhancebiocontrol ability of the yeasts against the pathogenic fungi in vitro(P = 0.05). C.laurentii was the most effective antagonist among the four yeasts and could completelycontrol spore germination of P.expansum and A.alternata when combined with Stroby at theconcentration of 100 L L-1. The yeasts, except R.glutinis, could grow well on nutrientyeast dextrose agar (NYDA) after 8 d incubation even at 20% CO2 concentration at 25℃.Particularly Trichosporon sp. showeda better adaptability to low temperature as comparedto other antagonists.
基金We are grateful to SaōPaulo Research Foundation for the financial support of this research and for the fellowships awarded to C.A.B.(FAPESP No.2011/19057-7)G.A.B.(FAPESP No.2012/21395-0)to Study Group of Cerrado Agroindustrial Processes(GEPPAC)of the Federal University of Grande Dourados to provide laboratories for plant material processing step.
文摘The increasing demand for safe food without preservatives or pesticides residues has encouraged several studies on natural products with antifungal activity and low toxicity.In this study,ethanolic extracts from leaves and fruit residues(peel and seeds)of three Brazilian savanna species(Acrocomia aculeata,Campomanesia adamantium and Caryocar brasiliense)were evaluated against phytopathogenic fungi.Additionally,the most active extract was chemically characterized by ESI-MS and its oral acute toxicity was evaluated.Extracts from C.brasiliense(pequi)peel and leaves were active against Alternaria alternata,Alternaria solani and Venturia pirina with minimal inhibitory concentrations between 350 and 1000 lg/mL.When incorporated in solid media,these extracts extended the lag phase of A.alternata and A.solani and reduced the growth rate of A.solani.Pequi peel extract showed better antifungal activity and their ESI-MS analysis revealed the presence of substances widely reported as antifungal such as gallic acid,quinic acid,ellagic acid,glucogalin and corilagin.The oral acute toxicity was relatively low,being considered safe for use as a potential natural fungicide.
文摘Wheat blast, caused by a fungal pathogen, <i><span style="font-family:Verdana;">Magnaporthe oryzae Tritichum </span></i><span style="font-family:Verdana;">(</span><i><span style="font-family:Verdana;">MoT</span></i><span style="font-family:Verdana;">) pathotype (wheat isolates), was first reported in Bangladesh among Asian countries in 2016. It is a serious disease of wheat causing yield failures and significant economic losses during epidemic years. Extensive use of persistent synthetic pesticides to control notorious wheat blast imposes enormous threat to human health and environment. In addition, the increasing demand for organic food has stimulated people to look for alternative methods. Nowadays, the need for synthetic chemical-free agricultural practices is gaining importance due to effective in managing crop pests, inexpensive, biodegradable, easily available and have low toxicity to non-target organisms. In order to identify active plants, 12 kinds of methanol extracts obtained from 12 medicinal plants were conducted </span><i><span style="font-family:Verdana;">in vitro</span></i><span style="font-family:Verdana;"> to test the effect against </span><i><span style="font-family:Verdana;">Magnaporthe oryzae Triticum </span></i><span style="font-family:Verdana;">(</span><i><span style="font-family:Verdana;">MoT</span></i><span style="font-family:Verdana;">) pathotype. The remarkable inhibitory activity {(29.6 ± 01.5) mm, (25.1 ± 01.0) mm and (20.0 ± 02.0) mm zone of inhibition)} exhibited by the extracts (5 mg/disk) obtained from </span><i><span style="font-family:Verdana;">Artemisia indica</span></i><span style="font-family:Verdana;"> (Nagdona), </span><i><span style="font-family:Verdana;">Persicaria orientalis</span></i><span style="font-family:Verdana;"> (Bishkatali) and </span><i><span style="font-family:Verdana;">Clerodendrum indicum</span></i><span style="font-family:Verdana;"> (Bamonhati), respectively. Other medicinal plant extracts did not show any significant or no activity at all. Therefore, the three plant extracts might be a promising source for developing natural fungicides against wheat blast.</span>
文摘The morphophysiological and molecular-genetic parameters of T. caries isolates collected from various fields of Southern Urals agrocenoses have been analysed. Isolate 1 of wheat callus had a high growth rate in vitro even in the presence of 0.1 mg/l fungicide Baitan. Isolate 2 of wheat callus had a low growth rate whereas 0.1 mg/l Baitan significantly inhibited its growth. Comparison of nucleotide sequences of 18S RNA gene of the two isolates showed high level of homology between them, but a large number of nucleotide substitutions have been found. The most characteristic excision was five nucleotides at position 461 of the isolate 2, compared with the isolate 1. Our results allow to assume that the environmental stress including high pesticide concentration may cause the resistance of T. caries pathogen to fungicides.
基金This research was supported by the Science Foundation No. 2011FZ 178, 2011FZ 180, 2014HD004, 14C26215303260 and National Natural Science Foundation of China （NSFC） No. 31260073, 31340019, 31160412, 41361056.
文摘Konjac （Amorphophallus muelleri）, a genus of tuberous plants in the Araceae family, is one of high-value crops in Southwest China. This study aimed at identifying the main pathogens causing tuber rot during storage ofA. muelleri and screening the effective fungicides, so as to prolong the storage period ofA. muelleri and decrease the losses. Isolation and identification, as well as pathogenicity test and retro-inoculation experiments were made for the pathogen causing tuber rot during storage ofA. muelleri in Kunming city, Yunnan province, China. The effective fungicides for the main pathogens were also screened in the laboratory. Six fungi were identified as the pathogens causing tuber rot of A. muelleri, which were Fusarium solani （Mart,） Sacc., Fusarium oxysporum Schlecht., Botrytis cinerea Pers., Alternaria alternata （Fr.） Keissl., Rhizopus nigricans Ehrenb., Penicillium ulaiense Hsieh, Su ＆ Tzean. The main pathogens causing postharvest diseases ofA. muelleri were F. solani, F. oxysporum and B. cinerea. The isolation frequencies of them were 33.9%, 10.5% and 19.4%, respectively. After artificial inoculation, the incidence of tubers infected by F. solani, F. oxysporum and B. cinerea was 100%, 83% and 95%, respectively. The results of chemical screening showed that, in potato dextrose agar （PDA） media plate, the compounds Fludioxonil （50% WP） and Boscalid （50% WG） were the most effective in controlling the three main pathogens, and the average effect reached more than 97%. The test of fungicidal antisepsis on tubers consisted ofA. muelleri being dipped in the 9,000x diluted solution of Fludioxonil （50% WP） or in the 3,500x diluted solution of Boscalid （50% WG） for 3 min and stored at room temperature （25 ℃） for 7 d and 15 d, respectively. The fungicidal effects of Fludioxonil against F. solani, F. oxysporum and B. cinerea for 7 d and 15 d were 88.6%/83.2%, 90.1%/84.7% and 93.0%/91.5%, respectively, whereas the fungicidal effects of Boscalid were 87.0%/85.3%, 89.0%/85.6% and 89.2%/89.1%, respectively. The results may provide useful information for the control ofpostharvest diseases ofA. muelleri.
基金Supported by Basic Projects in Yunnan Academy of Agricultural Sciences"Medicinal Plant Resources Nursery Building"~~
文摘[Objective] The research aimed to isolate and identify the pathogen of anthracnose of Ligusticum chuanxiong Hort,and make the antifungal test on four kinds of fungicides for selecting the optimum fungicides.[Method] The pathogenic fungi was separated according to Koch＇s rule and the shape characteristics were identified. The antifungal test of fungicides was made by using plate mycelium growth inhibition method.[Result] The pathogenic fungi was separated from leaves of Ligusticum chuanxiong Hort. and morphological characters were consistent with that of Colletotrichum gloeosporioides. In addition to chloroisobromine cyanuric acid,the other three fungicides could inhibit the mycelium growth. The growth inhibition rates of 1 000 times Metalaxyl＋mancozeb,zineb,Thiophanate-methyl for the mycelium were 26.8%,22.1%,59.8% respectively after 7 days.[Conclusion] The anthracnose was caused by Colletotrichum gloeosporioides. Ligusticum chuanxiong Hort. was a new record host plant of Colletotrichum gloeosporioides and the best inhibiting fungicide was Thiophanate methyl.
