ABSTRACT
Talius is a new fungicide containing the new active substance proquinazid. Talius is a fungicide against cereal powdery mildew (Blumeria graminis) in cereals and grass seed. The risk assessment was finalized at a meeting Mai 29, 2012, by VKM’s Scientific Panel on plant protection products (VKM). VKM is in particular asked by the Norwegian Food Safety Authority to look at the following: The human health risk for operators related to the properties of the active substance and the product. o The effects seen in studies on dog and if these effects warrant a classification for chronic toxicity. o The oncogenic effects in liver and thyroid. o The establishment of reference values (ADI, AOEL and ARfD). o Dermal absorption. o The classification and labelling of the active substances and the product. • The fate and behaviour in the environment and the ecotoxical effects and risks with regard to the properties of Talius and proquinazid. VKM’s conclusion is as follows: Health: VKM concluded that a less serious effect (dose-related ocular discharge increase) was seen in dogs in both the 90 days study and 1 year-study. The opinion of the Panel is that cholangiocarcinomas is relevant for the classification of cancer and VKM is concerned about these effects. VKM proposes an NOAEL of 1.2 mg/kg bw/day for proquinazid based on the 2 year study with rats. VKM support: The proposed ADI value of 0.01 mg/kg bw/day. • The proposed AOEL value of 0.02 mg/kg bw/day. The proposed ARfD value of 0.2 mg/kg bw/day. • The proposed classification from The Norwegian Food Safety Authority. VKM supports The Norwegian Food and Safety Authority calculations for dermal absorption under Norwegian directions for use (2.6 times higher dilution). Environment: Proquinazid can be persistent under prevailing conditions in Norway and the Panel considers the results from the Finnish PEC calculator to be relevant for Norwegian conditions and expects that repeated annual applications may cause accumulation in soil up to an equilibrium level under Norwegian conditions.The potential for groundwater contamination from leaching of proquinazid and its metabolites are low. There are minimal risks for toxic effects of proquinazid to terrestrial organisms, sediment dwelling organisms, aquatic plants, and algae with the proposed application regime. For fish and invertebrates minimal risks are calculated provided that a 3 m buffer zone is used.
ABSTRACT
Infinito is a new fungicide containing the two active substances fluopicolide and propamocarb-HCL. Infinito is a new generation fungicide to protect potatoes against the blight pathogen phytophtora infestans. The risk assessment was finalized at a meeting Mai 29, 2012, by the Panel on plant protection products of the Norwegian Scientific Committee for Food Safety (VKM). The Norwegian Food Safety Authority would like, in this regard, an assessment of the following: The fate and behaviour in the environment and the ecotoxicological effects and risks with regard to the properties of Infinito and the active substances. The Panel is particularly asked to look at the following: o The persistence of fluopicolide and its metabolites. o The leaching potential of fluopicolide and its metabolites. VKM considers both fluopicolide and its main metabolite M-01 (2,6-dichlorobenzamid (BAM)) to be persistent in Norwegian soils and surface waters. Other conclusions from VKM are as follows: Fluopicolide and its main metabolite may have a significant potential for soil accumulation after repeated use under Norwegian conditions.Fluopicolide shows low mobility in both studies and modelling. Metabolite M-01 (BAM) is however highly mobile.There is minimal risk for toxic effects of fluopicolide to terrestrial and aquatic organisms with the proposed application regime.
ABSTRACT
The aim of the experiment was to study the effect of a various concentrations of a systemic fungicide, metalaxyl on the expression of new proteins during early germination of maize. The study was conducted for 7 days. Our investigation showed the appearance of induced proteins ranging from 100-110kDa, 44kDa, 30kDa and 18-25kDa on different days of observation and different concentration of metalaxyl treatment, which is in line with the ?ndings in various abiotic stresses
ABSTRACT
In Hezhang county, Guizhou province, black spot tends to occur to Aconitum carmichaelii in the hot rainy summer, with the incidence up to 50%-70%, seriously impacting the yield and quality of the medicinal material. Thus, this study aims to clarify the pathogen and the occurrence characteristics. To be specific, the pathogen was isolated and identified according to Koch's postulates and the pathogenicity and biological characteristics were determined. In addition, the sensitivity of the pathogen to four microbial fungicides, four botanical fungicides, and five chemical fungicides was determined with the mycelium growth rate method for the purpose of screening out optimal fungicides. The pathogen was identified as Alternaria alternate, as evidenced by the similar colony morphology and microscopic characteristics and 99.55%-100% similarity in sequences of rDNA-ITS, LSU, 18S, and TEF of the two. The optimum growth conditions for A. alternata were 28 ℃, pH 8, and continuous darkness. Bacillus subtilis had strong inhibitory effect on the pathogen, and the inhibition rate was more than 90% when the concentration was 1 mg·L~(-1). In addition, difenoconazole and quinoline copper can also control the pathogen, with median effective concentration(EC_(50)) of 2.92 and 9.02 mg·L~(-1), respectively. This study lays a theoretical basis for the field control of black spot in A. carmichaelii.
Subject(s)
Aconitum , Alternaria , Fungicides, Industrial/pharmacology , MyceliumABSTRACT
The occurrence of powdery mildew (Microsphaera diffusa) in soybean (Glycine max L.) has increased in the last harvests. In order to study the efficiency of powdery mildew control due to the application of alternative products and conventional fungicide, trials were conducted in Ponta Grossa, PR, Brazil, during the 2013/2014 and 2014/2015 growing seasons. The design used was randomized blocks with four replications. The treatments for the experiments were: 1 - control; 2 - acibenzolar-S-methyl (Bion 500 WG®); 3 - calcium (Max Fruit®); 4 - Micronutrients: copper, manganese and zinc (Wert Plus®); 5 - Micronutrients: manganese, zinc and molybdenum (V6®); 6 - NK fertilizer (Hight Roots®); 7 - Ascophyllum nodosum (Acadian®) and 8 - fungicide (azoxystrobin + cyproconazole) (Priori XTRA®) with the addition of the adjuvant. Four applications of alternative products (phenological stages V3, V6, R1 and R5.1) and two of fungicide (phenological stages R1 and R5.1) were carried out. The parameters evaluated were powdery mildew severity and productivity. The severity data made it possible to calculate the area under the disease progress curve (AUDPG). Alternative products didn't reduce powdery mildew in the two harvests. The conventional fungicide treatment was the only one that controlled powdery mildew and didn't reduce the productivity in both experiments.
Subject(s)
Pesticides , Glycine max , Fungicides, Industrial , Erysiphe/pathogenicityABSTRACT
During the high-temperature and rainy season from June to October in 2017-2019,serious southern blight broke out in the Cynanchum stauntonii planting area in Tuanfeng county,Hubei province,which had a great impact on the yield and quality of medicinal materials. In this study,the pathogen of C. stauntonii was isolated,purified,and identified,and the pathogenicity was tested according to Koch's postulates. Meanwhile,the biological characteristics of the pathogen were analyzed. On this basis,the effective fungicides were screened in laboratory. Finally,the pathogen( BQ-1) was identified as Athelia rolfsii( Deuteromycotina,Basidiomycota,anamorph: Sclerotium rolfsii). The optimum growth conditions for BQ-1 were 25-30 ℃,p H 5-8,and alternating light and dark.The effective chemical fungicides were lime-sulphur-synthelic-solution( LSSS) and flusilazole,and the effective botanical fungicide was osthole. BQ-1 was highly homologous to the pathogen HS-1 of peanut southern blight,with the similarity of 18 S r DNA and TEF sequences at 99. 09%. The southern blight in C. stauntonii might be resulted from that in peanut. In the production of C. stauntonii,the following measures should be taken: avoiding rotation or neighboring with peanut,draining water from June to October to reduce humidity,and reasonably applying fungicides.
Subject(s)
Basidiomycota , Cynanchum , Fungicides, Industrial/pharmacology , HumidityABSTRACT
Arbuscular mycorrhizal fungi provided is beneficial to Salvia miltiorrhiza for increasing yield, promoting the accumulation of active ingredients, and alleviating S. miltiorrhiza disease etc. However, the application of fungicides will affect the benefit of arbuscular mycorrhizal fungi and there is little research about it. This article study the effect of four different fungicides: carbendazim, polyoxin, methyl mopazine, and mancozeb on mycorrhiza benefit to S. miltiorrhiza by the infection intensity of arbuscular mycorrhizal fungi, the growth of S. miltiorrhiza, and the content of active ingredients. RESULTS:: showed that different fungicides had different effects. The application of mancozeb had the strongest inhibitory effect on the mycorrhizal benefit to S. miltiorrhiza. Mancozeb significantly reduced the mycorrhizal colonization and the beneficial effect of arbuscular mycorrhizal fungi on the growth and the accumulation of active components of S. miltiorrhiza. The application of polyoxin had no significant effect on mycorrhizal colonization. Instead, it had a synergistic effect with the mycorrhizal benefit to promoting the growth and accumulation of rosmarinic acid of S. miltiorrhiza. The inhibitory strengths of four fungicides are: mancozeb>thiophanate methyl, carbendazim>polyoxin. Therefore, we recommend applying biological fungicides polyoxin and avoid applying chemical fungicides mancozeb for disease control during mycorrhizal cultivation of S. miltiorrhiza.
Subject(s)
Fungicides, Industrial/pharmacology , Mycorrhizae , Plant Roots , Salvia miltiorrhiza , SymbiosisABSTRACT
In order to identify the species and biological characteristics of the pathogen of southern blight from three kinds of Chinese medicine of Iridaceae(Belamcanda chinensis, Iris tectorum and I. japonica) in Dabie Mountains, the isolation, identification, pathogenicity and biological characteristics of the pathogens were studied according to Koch's postulates. In addition, 9 chemical fungicides, 3 botanical fungicides and 5 microbial fungicides were used to evaluate their inhibition to the isolates in vitro. The results showed that all the strains(SG-Q, YW-Q, and HDH-Q) isolated and purified from the diseased plants of B. chinensis, I. tectorum and I. japonica, respectively, were identified as Sclerotium rolfsii through morphological observation and sequence aligement of 18 S rDNA, rDNA-ITS and TEF. Field observations showed that the intensity of the disease incidence of three Iridaceae plants was B. chinensis>I. japonica> I. tectorum, and the pathogenicity of the strains was SG-Q>YW-Q>HDH-Q. For biological characteristics, SG-Q strain was suitable for growth under the 12 h light/12 h dark cycle, with the optimal growth temperature of 30 ℃ and pH of 5. Among the 9 tested chemical fungicides, 29% lime sulphure and 10% flusilazole had stronger inhibitory effect on mycelia growth of SG-Q. For 3 botanical fungicides, 1% osthol, 20% eugenol and 0.5% berberine could effectively inhibt the mycelial growth of SG-Q and cause the morphological variation of the pathogen. For 5 microbial fungicides, Trichoderma harzianum and Bacillus subtilis had better inhibition on the mycelium growth of SG-Q.
Subject(s)
Basidiomycota , Hypocreales , Iridaceae , MedicineABSTRACT
Abstract The unconscious use of pesticides causes various adverse effects on non-target organisms, including humans. Enzymes that control metabolism become the target of the pesticide and the organs are damaged due to toxic effects. Glutathione s-transferase (GST, EC 2.5.1.18), an important enzyme of the detoxification mechanism and antioxidant defense system, can be affected by such toxic substances. Therefore, the effect of fenarimol on GST enzyme activity was investigated in our study. For this, 200 mg/kg fenarimol was administered intraperitoneally to male and female rats at different periods (2, 4, 8, 16, 32, 64 and 72 hours). After application, GST enzyme activity was analysed in the liver, kidney, brain and small intestine tissues of the rats. According to our results, activation (liver, kidney, small intestine) or inhibition (brain) of the generally GST enzyme was observed in the tissues of rats exposed to fenarimol. It is thought that the increase and/or decrease in this enzyme activity may be the cause of the toxic effect of fenarimol.
Subject(s)
Animals , Rats , Pesticides/adverse effects , Glutathione S-Transferase pi , Enzyme Activation , Fungicides, Industrial/adverse effectsABSTRACT
Abstract Ceratobasidium ramicola is a fitopathogenic fungus that harmful and causes various levels of damage on several types of forestry and horticultural crops. The purpose of this study was to examine the effect of Acacia villosa, Myristica fragrans, Acacia mangium and Calliandra calothyrsus leaf extracts as tannin sources related to the in vitro inhibition of Ceratobasidium ramicola growth. The in vitro inhibition was performed by employing solid potato dextrose agar (PDA) medium to obtain the radial inhibition, while liquid potato dextrose broth (PDB) medium was used to obtain the biomass inhibition. Experimental design was based on in time nested-completely randomized design and statistical analysis was carried out with SAS software version 9.1. The result of radial growth inhibition of Ceratobasidium ramicola showed that tannin extracts of A. mangium and M. Fragrans were not significantly different to each other. Treatment of tannin extracts from A. villosa, M. fragrans, A. mangium and C. Calothyrsus with a concentration of 1% were significantly different with other concentrations and resulted the greatest inhibition values. Tannin extract of A. Mangium at 1% concentration produced the greatest radial inhibition by 33.2%. In most cases, the effective inhibition from tannin extract occurred at the 24h of incubation. The greatest biomass inhibition was produced on 1% tannin extract of A. mangium by 64.3%, while the lowest was produced from 1% tannin extract of M. fragrans by 27.0%.
Resumo Ceratobasidium ramicola é um fungo fitopatogênico prejudicial que causa vários danos em diversas culturas florestais e agrícolas. O objetivo deste estudo foi examinar o efeito dos extratos de folhas de Acacia villosa, Myristica fragrans, Acacia mangium e Calliandra calothyrsus como fontes de tanino relacionadas à inibição do crescimento in vitro de Ceratobasidium ramicola. A inibição in vitro foi realizada empregando o meio de ágar batata dextrose para obter a inibição radial, enquanto o meio de caldo de batata dextrose líquido foi usado para obter a inibição da biomassa. O projeto experimental foi fundamentado in time. O delineamento utilizado foi inteiramente casualizado, e a análise estatística foi realizada com o software SAS, versão 9.1. O resultado da inibição do crescimento radial de Ceratobasidium ramicola mostrou que os extratos de tanino de A. mangium e M. fragrans não diferiram significativamente entre si. Os tratamentos de extratos de tanino de A. villosa, M. fragrans, A. mangium e C. Calothyrsus, utilizando uma concentração de 1%, foram significativamente diferentes em comparação com outras concentrações e resultaram em maiores valores de inibição. O extrato de tanino de A. mangium a 1% de concentração produziu a maior inibição radial, com taxa de 33,2%. Na maioria dos casos, a inibição efetiva do extrato de tanino ocorreu em 24 horas de incubação. A maior inibição de biomassa foi produzida em 1% de extrato de tanino de A. Mangium, com taxa de 64,3%, enquanto a menor foi produzida a partir de 1% de extrato de tanino de M. fragrans, com taxa de 27%.
Subject(s)
Myristica , Acacia , Fabaceae , Tannins , Plant ExtractsABSTRACT
ABSTRACT: Asian soybean rust is one of the most destructive diseases that can be found in this crop. It can be largely controlled by fungicide application. The objective was to assess the sensitivity of P. pachyrhizi isolates to fungicides. The tests were performed in a completely randomized design, with six replicates. The sensitivity of twelve isolates to site-specific and multisite fungicides at concentrations of 0.1; 1.0; 10.0, and 100.0 mg L-1, plus a control with absence of fungicide (0.0 mg L-1) was assessed. Soybean leaflets were immersed in the appropriate fungicide solutions, disposed in wet chambers in plastic boxes, and inoculated using each uredinia suspension of P. pachyhrizi (5.0 x 104 uredospores mL-1), separately. Boxes were incubated for 20 days at a temperature of 23°C and a 12-hour photoperiod. Next, the number of uredinia per cm2 on the abaxial face of each leaflet was evaluated. The active ingredients prothioconazole, trifloxystrobin, fluxapiroxade, trifloxystrobin + prothioconazole, trifloxystrobin + bixafen + prothioconazole, azoxystrobin + benzovindiflupyr, and azoxystrobin + benzovindiflupyr + diphenoconazole were highly fungitoxic for the majority of the isolates, with EC50 lower than 1.0 mg L-1. Diphenoconazole, azoxystrobin, and fenpropimorph were considered moderately fungitoxic for nine of the twelve isolates, with EC50 between 1 and 10 mg L-1. The multisites mancozeb and copper oxychloride presented EC50 responses classified as low toxic for the twelve isolates and eight for chlorothalonil (EC50 between 10 mg L-1 and 50 mg L-1). Site-specific fungicides showed high-to-moderate fungitoxicity to P. pachyrhizi isolates, even as the multisites presented moderate-to-less toxic activity.
RESUMO: A ferrugem-asiática da soja é uma das doenças mais destrutivas que ocorre na cultura. Seu controle é baseado, principalmente, na aplicação de fungicidas. O objetivo foi avaliar a sensibilidade de isolados de P. pachyrhizi a fungicidas. Os ensaios foram realizados em delineamento inteiramente casualizado, com seis repetições. Por meio de teste de folíolos destacados de soja, foram avaliadas as sensibilidades de doze isolados do fungo a fungicidas sítio-específicos e multissítios, nas concentrações de 0,1; 1,0; 10,0 e 100,0 mg L-1, mais uma testemunha sem fungicida (0,0 mg L-1). Os folíolos de soja foram imersos nas devidas soluções fungicida, dispostos em câmaras úmidas em caixas gerbox e inoculados com as devidas suspensões de esporos de P. pachyhrizi (5,0x104 uredosporos mL-1). As caixas foram incubadas durante 20 dias, em temperatura de 23 oC e fotoperíodo de 12 h. Em seguida, avaliou-se o número de urédias cm-2 da face abaxial de cada folíolo. Os ingredientes ativos protioconazol, trifloxistrobina, fluxapiroxade, trifloxistrobina + protioconazol, trifloxistrobina + bixafem + protioconazol, azoxistrobina + benzovindiflupir e azoxistrobina + benzovindiflupir + difenoconazol foram altamente fungitóxicos para a maioria dos isolados, com CE50 menor do que 1,0 mg L-1. Difenoconazol, azoxistrobina e fenpropimorfe foram considerados medianamente fungitóxicos para nove dos doze isolados, com CE50 entre 1 e 10 mg L-1. Os multissítios mancozebe e oxicloreto de cobre apresentaram respostas de CE50 classificadas como pouco tóxicas para os doze isolados do fungo e o clorotalonil para oito deles (CE50 entre 10 e 50 mg L-1). Os fungicidas sítio-específico apresentaram alta a moderada fungitoxicidade aos isolados de P. pachyrhizi oriundos dos distintos locais, enquanto os multissítios apresentaram atividade moderada a pouco tóxica.
ABSTRACT
The frequent tank mixing of phytosanitary products, adjuvants, and foliar fertilizers highlights the lack of information which sustains decisions about what products can be mixed for spray application. Thus, the aim of this study was to evaluate the physical and chemical characteristics of fungicides, herbicides, and insecticides in combination with some adjuvants on the Brazilian market. The experimental design was completely randomized and spray mixes of the phytosanitary products: fungicide (azoxystrobin+benzovindiflupir), herbicide (diamônio salt of N-(phosponomethyl)) or insecticide (fenpropathrin) were evaluated in combination with adjuvants (mineral oil base, foliar fertilizer or lecithin + propionic acid), and in two application rates (95 and 52 L ha-1); all with four replications. Surface tension, electrical conductivity, pH, dynamic viscosity and density of spray mixes were evaluated. The adjuvants presented characteristics capable of significantly altering the physicochemical properties of the phytosanitary spray mixes, and thus, alter the biological effectiveness and efficiency of the spray applications. However, its effects are also dependent on the phytosanitary product added to the spray mix, which makes general recommendations a difficult task. The greatest pH reduction, as well as the greatest increase in electrical conductivity, were caused by the adjuvant lecithin + propionic acid. All phytosanitary products and adjuvants studied, associated or not, resulted in a reduction in the surface tension of the spray mix in relation to water. The magnitude of change of density and dynamic viscosity promoted by adjuvants was lower than the other characteristics evaluated.
A realização frequente de misturas em tanque de produtos fitossanitários, adjuvantes e fertilizantes foliares traz à tona a carência de informações que amparem as decisões sobre quais produtos podem ser misturados. O objetivo deste trabalho foi avaliar características físicas e químicas de caldas fungicidas, herbicidas e inseticidas em combinação com alguns adjuvantes do mercado. O delineamento experimental utilizado foi inteiramente casualizado, sendo avaliadas diferentes caldas com o fungicida azoxistrobina+benzovindiflupir, herbicida sal de diamônio de N-(phosponomethyl) e inseticida fenpropatrina, em combinação com adjuvantes a base de óleo mineral, fertilizante foliar e lecitina de soja+ácido propiônico, considerando duas taxas de aplicação (95 e 52 L ha-1), todos os tratamentos com quatro repetições. Foram avaliadas as seguintes características: tensão superficial, condutividade elétrica, pH, viscosidade dinâmica e densidade. Os adjuvantes apresentaram características capazes de alterar significativamente as propriedades físico-químicas das caldas fitossanitárias, podendo, assim, alterar a eficácia biológica e a eficiência das aplicações. Contudo, seu efeito também é dependente do produto fitossanitário adicionado à calda, o que dificulta generalizações. A maior redução do pH, bem como o maior aumento na condutividade elétrica da calda, foram ocasionados pelo adjuvante lecitina+ácido propiônico. Todos os produtos fitossanitários e adjuvantes, de forma associada ou não, provocaram redução na tensão superficial da calda em relação à água. A magnitude das alterações de densidade e viscosidade dinâmica promovida pelos adjuvantes foi inferior às demais características avaliadas.
Subject(s)
Pesticide Industry , Fungicides, Industrial , Herbicides , InsecticidesABSTRACT
Alternaria leaf blight caused by Alternaria brassicae and Alternaria brassicola, is one of the most destructive diseases of mustard (Brassica campestris, B. juncea and B.napus) in West Bengal, causing considerable damages to the crop. The experiment was conducted under in vitro and in vivo conditions to see the effect of bio-agents, plant extracts and chemicals (fungicide and SAR compound) against Alternaria brassicae. Maximum inhibition in mycelial growth (95.56%) was observed with Mancozeb 75% Wp followed by Lantana camera (80%), Salicylic acid (73.33%), Allium sativum (54.44%) and Zingiber officinale (17.78%) in comparison to control. Foliar spray with fungicide (Mancozeb 75% WP @ 0.2%) was found to be most effective in reducing disease severity (81,23%) and infection rate which increased the yield (77.23%) of mustard over untreated control. Among the plant extracts, Lantana camera was found to be excellent in controlling the Alternaria blight infection in the field (71.92% reduction in disease severity and 68.18% increase in yield) in comparison to salicylic acid (SAR compound) and bio-agent (Trichoderma viride) 48.33% and 36.27% reduction in disease severity respectively.
ABSTRACT
Abstract The use of chemical defensives to control fungal diseases has by consequence to impact negatively over the environment and human health, this way, the use of plant extracts with antifungal properties along with proper cultural management makes viable an alternative plant production control, specially for familiar and organic cultures. The objective of this study was to perform phytochemical and antioxidant analysis of Byrsonima crassifolia (canjiqueira) barks and evaluate its antifungal potential over Fusarium solani and Sclerotinia sclerotiorum mycelial growth. The ethanol extract from plants collected in Pantanal, Mato Grosso do Sul, Brazil was submitted to phytochemical prospection, total phenol and flavonoids quantification and antioxidant activiy determination (DPPH). To evaluate antifungal activity concentrations of 800, 1200, 1600, 2000 and 2400 µg 100 mL-1 of ethanol extract were used. Which concentration was separately incorporated in agar (PDA) and shed in Petri dishes, followed by the fungi mycelial disc where the colonies diameter was measured daily. Negatives control with agar without extract and agar with an ethanol solution were used. The B. crassifolia ethanol extract presented inhibitory activity over the fungi studied where concentrations of 800 and 1600 µg 100 mL-1, inhibited 38% of the mycelial growth of F. solani; to S. sclerotiorum the best concentration was 2400 µg 100 mL1, reducing 37.5%. The antifungal bark extract potential of this specie is attributed to phenolic compounds and to triterpenes derivatives.
Resumo A aplicação de defensivos químicos para o controle de doenças fúngicas tem por consequência impactos sobre o ambiente e a saúde humana, dessa forma, a utilização de extratos vegetais com propriedades antifúngicas associado ao manejo adequado de culturas, torna-se uma proposta viável de controle alternativo, principalmente na agricultura orgânica e familiar. Neste sentido, objetivou-se neste trabalho realizar a análise fitoquímica e antioxidante das cascas de Byrsonima crassifolia (canjiqueira) e avaliar seu potencial antifúngico sobre o crescimento micelial de Fusarium solani e Sclerotinia sclerotiorum. O extrato etanólico das cascas da planta, coletadas no Pantanal do Rio Negro, em Mato Grosso do Sul, foi submetido à prospecção fitoquímica, quantificação de fenóis totais e flavonoides e determinação da atividade antioxidante (DPPH). Para a avaliação da atividade antifúngica foram utilizadas as concentrações de 800, 1200, 1600, 2000 e 2400 µg 100 mL-1 do extrato etanólico. Cada concentração foi incorporada, separadamente, em ágar BDA, e vertida em placas de petri, seguido do disco de micélio do fungo, onde o diâmetro das colônias foi medido diariamente. Utilizou-se como controle negativo, ágar sem extrato e ágar com solução etanólica. O extrato etanólico de B. crassifolia apresentou atividade inibitória sobre os fungos estudados, onde as concentrações de 800 e 1600 µg 100 mL-1, inibiram 38% do crescimento micelial de F. solani; para S. sclerotiorum, a melhor concentração foi de 2400 µg 100 mL1, com 37,5% de redução de crescimento. Atribui-se o potencial antifúngico do extrato da casca da espécie aos compostos fenólicos e derivados de triterpenos.
Subject(s)
Plant Extracts/chemistry , Malpighiaceae/chemistry , Antifungal Agents/pharmacology , Antifungal Agents/chemistry , Antioxidants/pharmacology , Antioxidants/chemistry , Soil Microbiology , Plant Extracts/pharmacology , Phytochemicals , Fungi/drug effectsABSTRACT
The biocidal agrochemicals commonly used in agriculture can remain in the soil, affecting the environmental conditions and causing serious risks to health. Knowing that soil microorganisms, especially those from the rhizosphere, can degrade environmental xenobiotics, it was evaluated the potential of bacteria isolated from Coriandrum sativum L. rhizosphere to biodegrade carbendazim (MBC), a fungicide extensively used by agriculturists from rural farming communities in Manaus, Amazonas. Cultures carried out in medium containing carbendazim as a sole carbon source enabled the isolation of 80 bacteria, in the established conditions. Assays to determine degradation potential allowed the selection of the two elite isolates identified as Stenotrophomonas sp. and Ochrobactrum sp. Quantitative assays with each strain individually or in consortium, were carried out using minimal salt medium added with carbendazim (250 µg mL-1) and incubated at 30°C, under agitation (125 rpm) for 21 days. Samples used in the biodegradation test were HPLC analyzed for final fungicide quantitation. The Stenotrophomonas sp. strain was more efficient (68.9%) to degrade carbendazim and showed no toxicity in tests with Artemia salina.
Agrotóxicos são comumente utilizados na produção agrícola, podendo persistir no solo, afetar a qualidade do ambiente e causar sérios riscos à saúde. Sabendo-se que micro-organismos do solo, principalmente aqueles da rizosfera, podem degradar produtos xenobióticos avaliou-se o potencial de bactérias isoladas da rizosfera de Coriandrum sativum L. em degradar carbendazim, um fungicida usado extensivamente em comunidades de agricultores rurais em Manaus, Amazonas. Procedimentos de cultivo em meio, contendo carbendazim como única fonte de carbono, mostraram que 80 bactérias cresceram nas condições estabelecidas. Ensaios de eficiência de degradação permitiram a seleção dos dois melhores isolados que foram identificados como Stenotrophomonas sp. e Ochrobactrum sp. Os ensaios quantitativos, com cada cepa individualmente e com as duas em consórcio, foram conduzidos em meio mínimo contendo sais, acrescido de carbendazim (250 µg mL-1) e incubados a 30°C, 125 rpm, por 21 dias. A quantificação final do fungicida nas amostras do ensaio de biodegradação foi realizada em HPLC. A linhagem Stenotrophomonas sp. apresentou maior eficiência, degradando 68,9% do total de carbendazim e não apresentou toxicidade nos testes realizados com Artemia salina.
Subject(s)
Amazonian Ecosystem , Coriandrum , Pesticides , SoilABSTRACT
A method for simultaneous determination of 25 kinds of fungicides in cereals, vegetables and fruits using SPE-LC-Q-TOF/MS technique was developed.The samples were extracted with acetonitrile containing 1% (V/V) acetic acid, purified by solid phase extraction (SPE) with a Crabon/NH2 cartridge, eluted with acetonitrile-toluene(3∶1, V/V), separated by a reversed phase C18 column, gradiently eluted with acetonitrile and 0.1% formic acid solution (Containing 5 mmol/L ammonium acetate), determined by LC-Q-TOF/MS, and quantified by external standard method.A data base of the accurate mass numbers and a library which contains 25 kinds of fungicides were established.The automatic retrieval of detection results was carried on according to the characteristics of the compound, such as accurate mass, retention time, isotope peak distribution, isotopic ratios, and so on.Based on the above results, the qualitative identifications of the 25 new fungicides were accomplished without the contrast of standard substances.The results indicated that 25 fungicides showed good linearity in the range of 0.02-200 μg/L, and the limits of detection (LOD) and the limits of quantification (LOQ) were 0.01-5.00 μg/kg and 0.02-20.00 μg/kg, respectively.The linear relative coefficients were greater than 0.995.The recoveries were in the range 71.8%-114.0% and the relative standard deviations (RSD) were ranged from 0.1% to 21.3% (n=3).The method has some advantages such as simplicity, rapidity and high sensitivity, and is suitable for the rapid determination of the common fungicides in cereals, vegetables and fruits.
ABSTRACT
A method of ultra performance liquid chromatography-quadrupole-time of flight-mass spectrometry ( UPLC-Q-TOF MS) was developed to determine 35 kinds of illegally added chemical fungicides in pesticide formulations. The samples were pretreated based on the ultrasonic extraction by the solvent of methanol, and then separated on a Zorbax C18(100 mm×1. 8 mm, 2. 1 μm) column by a gradient elution with 0. 1% formic acid aqueous solution and acetonitrile as the mobile phase. The mass spectrometer was operated under positive mode. Under the optimal conditions, the recoveries at three spiked levels (0. 2, 0. 4, and 2. 0 mg/kg) were in the range of 81. 0%-101. 3% and the RSDs were 1. 0%-4. 4%. Based on the developed method, 100 samples were analyzed, and among which 6 samples were screened out chemical fungicides. The proposed method was high-efficient, accurate and reliable for the qualitatively screening of illegaly added chemical fungicides.
ABSTRACT
We identified two genes related to fungicide resistance in Fusarium fujikuroi through random mutagenesis. Targeted gene deletions showed that survival factor 1 deletion resulted in higher sensitivity to fungicides, while deletion of the gene encoding F-box/WD-repeat protein increased resistance, suggesting that the genes affect fungicide resistance in different ways.
Subject(s)
Fusarium , Gene Deletion , MutagenesisABSTRACT
Abstract The use of chemical defensives to control fungal diseases has by consequence to impact negatively over the environment and human health, this way, the use of plant extracts with antifungal properties along with proper cultural management makes viable an alternative plant production control, specially for familiar and organic cultures. The objective of this study was to perform phytochemical and antioxidant analysis of Byrsonima crassifolia (canjiqueira) barks and evaluate its antifungal potential over Fusarium solani and Sclerotinia sclerotiorum mycelial growth. The ethanol extract from plants collected in Pantanal, Mato Grosso do Sul, Brazil was submitted to phytochemical prospection, total phenol and flavonoids quantification and antioxidant activiy determination (DPPH). To evaluate antifungal activity concentrations of 800, 1200, 1600, 2000 and 2400 µg 100 mL-1 of ethanol extract were used. Which concentration was separately incorporated in agar (PDA) and shed in Petri dishes, followed by the fungi mycelial disc where the colonies diameter was measured daily. Negatives control with agar without extract and agar with an ethanol solution were used. The B. crassifolia ethanol extract presented inhibitory activity over the fungi studied where concentrations of 800 and 1600 µg 100 mL-1, inhibited 38% of the mycelial growth of F. solani; to S. sclerotiorum the best concentration was 2400 µg 100 mL1, reducing 37.5%. The antifungal bark extract potential of this specie is attributed to phenolic compounds and to triterpenes derivatives.
Resumo A aplicação de defensivos químicos para o controle de doenças fúngicas tem por consequência impactos sobre o ambiente e a saúde humana, dessa forma, a utilização de extratos vegetais com propriedades antifúngicas associado ao manejo adequado de culturas, torna-se uma proposta viável de controle alternativo, principalmente na agricultura orgânica e familiar. Neste sentido, objetivou-se neste trabalho realizar a análise fitoquímica e antioxidante das cascas de Byrsonima crassifolia (canjiqueira) e avaliar seu potencial antifúngico sobre o crescimento micelial de Fusarium solani e Sclerotinia sclerotiorum. O extrato etanólico das cascas da planta, coletadas no Pantanal do Rio Negro, em Mato Grosso do Sul, foi submetido à prospecção fitoquímica, quantificação de fenóis totais e flavonoides e determinação da atividade antioxidante (DPPH). Para a avaliação da atividade antifúngica foram utilizadas as concentrações de 800, 1200, 1600, 2000 e 2400 µg 100 mL-1 do extrato etanólico. Cada concentração foi incorporada, separadamente, em ágar BDA, e vertida em placas de petri, seguido do disco de micélio do fungo, onde o diâmetro das colônias foi medido diariamente. Utilizou-se como controle negativo, ágar sem extrato e ágar com solução etanólica. O extrato etanólico de B. crassifolia apresentou atividade inibitória sobre os fungos estudados, onde as concentrações de 800 e 1600 µg 100 mL-1, inibiram 38% do crescimento micelial de F. solani; para S. sclerotiorum, a melhor concentração foi de 2400 µg 100 mL1, com 37,5% de redução de crescimento. Atribui-se o potencial antifúngico do extrato da casca da espécie aos compostos fenólicos e derivados de triterpenos.
ABSTRACT
Abstract Ceratobasidium ramicola is a fitopathogenic fungus that harmful and causes various levels of damage on several types of forestry and horticultural crops. The purpose of this study was to examine the effect of Acacia villosa, Myristica fragrans, Acacia mangium and Calliandra calothyrsus leaf extracts as tannin sources related to the in vitro inhibition of Ceratobasidium ramicola growth. The in vitro inhibition was performed by employing solid potato dextrose agar (PDA) medium to obtain the radial inhibition, while liquid potato dextrose broth (PDB) medium was used to obtain the biomass inhibition. Experimental design was based on in time nested-completely randomized design and statistical analysis was carried out with SAS software version 9.1. The result of radial growth inhibition of Ceratobasidium ramicola showed that tannin extracts of A. mangium and M. Fragrans were not significantly different to each other. Treatment of tannin extracts from A. villosa, M. fragrans, A. mangium and C. Calothyrsus with a concentration of 1% were significantly different with other concentrations and resulted the greatest inhibition values. Tannin extract of A. Mangium at 1% concentration produced the greatest radial inhibition by 33.2%. In most cases, the effective inhibition from tannin extract occurred at the 24h of incubation. The greatest biomass inhibition was produced on 1% tannin extract of A. mangium by 64.3%, while the lowest was produced from 1% tannin extract of M. fragrans by 27.0%.
Resumo Ceratobasidium ramicola é um fungo fitopatogênico prejudicial que causa vários danos em diversas culturas florestais e agrícolas. O objetivo deste estudo foi examinar o efeito dos extratos de folhas de Acacia villosa, Myristica fragrans, Acacia mangium e Calliandra calothyrsus como fontes de tanino relacionadas à inibição do crescimento in vitro de Ceratobasidium ramicola. A inibição in vitro foi realizada empregando o meio de ágar batata dextrose para obter a inibição radial, enquanto o meio de caldo de batata dextrose líquido foi usado para obter a inibição da biomassa. O projeto experimental foi fundamentado in time. O delineamento utilizado foi inteiramente casualizado, e a análise estatística foi realizada com o software SAS, versão 9.1. O resultado da inibição do crescimento radial de Ceratobasidium ramicola mostrou que os extratos de tanino de A. mangium e M. fragrans não diferiram significativamente entre si. Os tratamentos de extratos de tanino de A. villosa, M. fragrans, A. mangium e C. Calothyrsus, utilizando uma concentração de 1%, foram significativamente diferentes em comparação com outras concentrações e resultaram em maiores valores de inibição. O extrato de tanino de A. mangium a 1% de concentração produziu a maior inibição radial, com taxa de 33,2%. Na maioria dos casos, a inibição efetiva do extrato de tanino ocorreu em 24 horas de incubação. A maior inibição de biomassa foi produzida em 1% de extrato de tanino de A. Mangium, com taxa de 64,3%, enquanto a menor foi produzida a partir de 1% de extrato de tanino de M. fragrans, com taxa de 27%.