Inactivation of isolated fungi on Erythrina velutina Willd. seeds through atmospheric plasma

Abstract This study aimed to evaluate the effect of atmospheric plasma application on the inactivation of fungi on the surface of Erythrina velutina seeds and on isolated fungal colonies. Two experiments were conducted using a completely randomized design. First, plasma was applied to the surface of the seeds using helium gas and atmospheric plasma for 3, 6, and 9 min in addition to the control (untreated seeds), constituting seven treatments with five repetitions each. In the second experiment, Petri dishes containing the inoculum of different fungi were treated with atmospheric air plasma for 3, 6, and 9 min (Air-3, Air-6, and Air-9) and were compared with untreated fungi in Petri dishes without treatment (control), totaling four treatments and five repetitions each. We found that the application of atmospheric air plasma to E. velutina seeds for 9 min had an antimicrobial effect on the fungi Aspergillus niger, Aspergillus flavus, Fusarium sp., Brachysporium sp., and Rhizopus sp. The formation of fungal colonies isolated from E. velutina seeds was also inhibited by 3 min of exposure to atmospheric air plasma, except for A. niger, whose inhibition occurred after 6 min of exposure to atmospheric plasma.

Resumo Este trabalho teve como objetivo avaliar o efeito da aplicação de plasma atmosférico na inativação de fungos na superfície de sementes de Erythrina velutina e em colônias fúngicas isoladas. Dois experimentos foram realizados em delineamento inteiramente casualizado: no primeiro, o plasma foi aplicado na superfície das sementes usando gás hélio e plasma atmosférico por três, seis e nove minutos, além do controle (sementes sem tratamento), constituindo sete tratamentos com cinco repetições cada; no segundo experimento, placas de Petri contendo o inóculo de diferentes fungos foram tratadas com plasma atmosférico por três, seis e nove minutos (Air-3, Air-6 e Air-9) e comparadas com fungos não tratados em placas de Petri sem tratamento (controle), totalizando quatro tratamentos e cinco repetições cada. Descobrimos que a aplicação de plasma atmosférico nas sementes de E. velutina por nove minutos teve efeito antimicrobiano sobre os fungos Aspergillus niger, Aspergillus flavus, Fusarium sp., Brachysporium sp. e Rhizopus sp. A formação de colônias fúngicas isoladas de sementes de E. velutina também foi inibida por três minutos de exposição à aplicação de plasma atmosférico, exceto para A. niger, cuja inibição ocorreu a partir de 6 minutos de exposição à aplicação de plasma atmosférico.

Inactivation of isolated fungi on Erythrina velutina Willd. seeds through atmospheric plasma / Inativação de fungos isolados em sementes de Erythrina velutina Willd. por meio do plasma atmosférico

Abstract This study aimed to evaluate the effect of atmospheric plasma application on the inactivation of fungi on the surface of Erythrina velutina seeds and on isolated fungal colonies. Two experiments were conducted using a completely randomized design. First, plasma was applied to the surface of the seeds using helium gas and atmospheric plasma for 3, 6, and 9 min in addition to the control (untreated seeds), constituting seven treatments with five repetitions each. In the second experiment, Petri dishes containing the inoculum of different fungi were treated with atmospheric air plasma for 3, 6, and 9 min (Air-3, Air-6, and Air-9) and were compared with untreated fungi in Petri dishes without treatment (control), totaling four treatments and five repetitions each. We found that the application of atmospheric air plasma to E. velutina seeds for 9 min had an antimicrobial effect on the fungi Aspergillus niger, Aspergillus flavus, Fusarium sp., Brachysporium sp., and Rhizopus sp. The formation of fungal colonies isolated from E. velutina seeds was also inhibited by 3 min of exposure to atmospheric air plasma, except for A. niger, whose inhibition occurred after 6 min of exposure to atmospheric plasma.

Resumo Este trabalho teve como objetivo avaliar o efeito da aplicação de plasma atmosférico na inativação de fungos na superfície de sementes de Erythrina velutina e em colônias fúngicas isoladas. Dois experimentos foram realizados em delineamento inteiramente casualizado: no primeiro, o plasma foi aplicado na superfície das sementes usando gás hélio e plasma atmosférico por três, seis e nove minutos, além do controle (sementes sem tratamento), constituindo sete tratamentos com cinco repetições cada; no segundo experimento, placas de Petri contendo o inóculo de diferentes fungos foram tratadas com plasma atmosférico por três, seis e nove minutos (Air-3, Air-6 e Air-9) e comparadas com fungos não tratados em placas de Petri sem tratamento (controle), totalizando quatro tratamentos e cinco repetições cada. Descobrimos que a aplicação de plasma atmosférico nas sementes de E. velutina por nove minutos teve efeito antimicrobiano sobre os fungos Aspergillus niger, Aspergillus flavus, Fusarium sp., Brachysporium sp. e Rhizopus sp. A formação de colônias fúngicas isoladas de sementes de E. velutina também foi inibida por três minutos de exposição à aplicação de plasma atmosférico, exceto para A. niger, cuja inibição ocorreu a partir de 6 minutos de exposição à aplicação de plasma atmosférico.

Isolation and Characterization of Antibiotic Producing Fungi from Soil

This study was aimed to isolate and characterize antibiotic producing fungi from the soil environment within Ahmadu Bello University main campus Samaru, Zaria. Soil samples were collected from five different locations within Ahmadu Bello University main campus for the Isolation of fungi. Spread plate method involving serial dilution technique was used for the Isolation using Saboraud Dextrose Agar (SDA). Six species of fungi were isolated from the soil samples and then characterized microscopically and macroscopically. The fungi were Aspergillus niger, Aspergillus fumigatus, Aspergillus sp, Penicillium sp, Fusarium sp (P14) and Fusarium sp (P15). Sensitivity test using Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae as test pathogens was employed to determine the ability of the fungal isolates to produce antimicrobials. All the fungal isolates were found to inhibit the growth of at least one of the test pathogens except Fusarium sp (P14). Aspergillus niger produces zones of inhibition of 9mm, 5mm and 6mm against Staphylococcus aureus, Escherichia coli, and Klebsiella pneumoniae, Aspergillus fumigatus produces zones of inhibition of 5mm against Escherichia coli and Klebsiella pneumoniae. Aspergillus sp produced zones of 6mm against Staphylococcus aureus and Escherichia coli, Penicillium sp which produces a zone of 10mm, 7mm and 6mm against Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae. The findings of this study show that antibiotic-producing fungus are prevalent in the soil of Ahmadu Bello University's main campus in Samaru, Zaria, and that these strains could be used by pharmaceutical companies to produce antibiotics from local sources.

Clinical profile and treatment outcomes of Fusarium keratitis

Purpose: To determine the seasonality, clinical profile, and treatment outcome of Fusarium keratitis. Methods: A retrospective medical chart review of 97 patients with culture?proven Fusarium keratitis at a tertiary eye care institution from January 2018 to December 2019. Results: The median (SD) age at enrollment was 44.6 (16) years; 75 (79.8%) of them were male. Presence of infiltrate less than 4 mm2 at baseline indicated 4.4 times the odds of achieving final BCVA more than 20/60 (95% CI: 1.4–13.3; P = 0.008). The absence of surgical management indicated 8.1 times the odds of achieving final BCVA of more than 20/60 (95% CI: 0.9–71.5; P = 0.06). The visual acuity at presentation, duration between symptoms and presentation, history of ocular trauma, previous use of topical medications, and presence of hypopyon were not identified as significant predictors of final BCVA in the multivariable regression analysis. Conclusion: Smaller infiltrate size and absence of surgical management are the significant predictors of good visual outcome. Visual outcome of Fusarium keratitis is poor, and a significant number of patients did not respond to anti?fungal therapy and had to undergo surgeries. To the best of our knowledge, this is the largest case series on Fusarium keratitis to date

siRNA quelling of tri4 and tri5 genes related to deoxynivalenol synthesis in Fusarium graminearum and Fusarium culmorum

Aim: This study was conducted to investigate the quelling of tri4 and tri5 genes associated with deoxynivalenol, most common class B trichothecene, via siRNA application. Methodology: In this study, one Fusarium graminearum (4F) and two F. culmorum (9F and 20F) isolates, expressing high levels of tri4 and tri5 genes, were targeted for siRNA-based silencing. Full length tri4 and tri5 genes were amplified from all isolates, sequenced and then subjected to CLUSTALW analysis for designing siRNA molecules. Totally designed six siRNAs were separately co-transfected together with helper plasmids (pEGFP75 and pAN7-1) as 36 combinations into protoplast cultures and quelling was analysed via real time polymerase chain reaction, thin layer chromatography and spectrofluorimetric analysis. Results: Alignment of both tri4 and tri5 genes’ sequencing revealed high levels of similarity between isolates (94-99% and 95-100%, respectively). Transfection efficiency ranged from 50±0.00/5x104 to 99.33±10.06/5x104 and relative fluorescence unit values were calculated between 1.37±0.07 and 2.89±0.06. The 0.7 kb length fragments of hph and GFP were amplified from transfectants. The real time PCR revealed that tri4 was completely suppressed in 30 experimental sets whereas down-regulations of tri5, ranging from 74.5 to 99%, was detected in remaining 6 experiment groups. Thin layer chromatography assay also showed that siRNA-transfected Fusarium samples showed no deoxynivalenol spots. Interpretation: This study revealed that tri4 and tri5 genes can be targeted in the development of less deoxynivalenol (DON)-producing strains through RNAi. Moreover, current study has great importance as it demonstrates that quelling can be used as a potential strategy in controlling diseases caused by phytopathogenic species.

Identification and Characterizations of Pathogenic Fungal Species Associated with Symptoms of Cassava Anthracnose in Ivory Coast

Cassava anthracnose is a plant disease that affects cassava stems, petioles and fruits. The aim of this study was to analyze the diversity of cassava anthracnose symptoms in Ivory Coast and then to identify and characterize the associated fungal genera. Surveys were carried out in all agricultural zones of the country from July to November, in 2014, 2015, 2016 and 2017. Infected samples consisting of stems cut with a small number of superficial cankers (0.3%), distorted stems (25.77%), and necrotic stems and petioles (65.18%) were collected. Also, withered and dried apical buds (8.76%) were harvested. Fungal pathogens derived from samples were Colletotrichum gloeosporioides (35.08%), Fusarium sp. (27.19%) and Botrytis sp. (19.73%) genera and undetermined strains (17.98%). Genera were characterized by morphological and microscopic characteristics. Parasitic pressure increased to 80 and 100% respectively for Botrytis sp. genus and Colletotrichum gloeosporioides and Fusarium sp genera. Fungal genera have caused lesions on stem and petioles in green house with diameters sizes 46, 71 and 72 mm respectively for genera Botrytis sp, Fusarium sp and Colletotrichum gloeosporioides. Aggressiveness index of Botrytis sp. genus was 3 and 4 respectively for Colletotrichum gloeosporioides and Fusarium sp. genera. The mycoflora of cassava aerial organs alteration, linked to the symptoms of anthracnose, is composed of genera of great economic importance and scientific interest.

In Vitro Antimicrobial Activity And Mic Of The Extracellular Ethyl Acetate Crude Extract Of Endophytic Fungi Fusarium Sp. Isolated From Tephrosia Purpurea Root

Objective: The objective of the present investigation was to find antimicrobial and MIC of endophytic fungi Fusarium sp. isolated from Tephrosia purpurea root. Methods: Well diffusion assay was performed to find out the antimicrobial activity and Resazurin dye reduction method was performed to find out MIC of the extract. Result: The extract showed the highest zone of inhibition of 22.66±0.57 mm, (Bacillus subtilis, MTCC-441) for Gram-positive bacteria and 20.66±0.57 mm, (E. coli, MTCC-443) for Gram-negative bacteria. Furthermore, the MIC of the extract was found to be (31.25 µg/ml-125 µg/ml). Conclusion: Hence, the endophytic fungi isolated from the Tephrosia purpurea root, i.e. Fusarium sp. showed good antimicrobial activity and hence can be used to find a novel drug.

Hongos fitopatógenos asociados a la enfermedad de marchitez vascular y muerte regresiva en plantaciones de Tectona grandis L. f. (teca) en el Trópico Húmedo Ecuatoriano / Phytopathogen fungi related to vascular wilt and die back in Tectona grandis L. f (teak) field in Ecuadorian Tropical Rainforest

Plantaciones de teca (Tectona grandis L.f.) en Ecuador están siendo afectadas por una compleja enfermedad de marchitez vascular y muerte regresiva, con características epidémicas, sin que hasta el momento se conozca el o los agentes causales. Se planteó describir la sintomatología de la enfermedad e identificar los hongos fitopatógenos asociados a árboles enfermos en el Trópico Húmedo Ecuatoriano mediante morfofisiología. Se seleccionaron tres plantaciones de 2, 5 y 7 años de edad, en cada una se delimitó tres parcelas de 500 m2. Se realizó la descripción sintomatológica, evaluó la incidencia y severidad de la enfermedad empleando una escala de cinco categorías. Por parcela se diseccionaron tres árboles, cuyos tejidos se llevaron al laboratorio, donde se emplearon tres estrategias metodológicas (cámara húmeda, sandwiches de zanahoria, y medio de cultivo papa-dextrosa-agar; PDA) para estimular la expresión de los fitopatógenos. En árboles enfermos se detectó clorosis, pérdida de turgencia, ápices de crecimiento secos, emisión de brotes epicormicos en el fuste, y marchitez fulminante. Se aisló e identificó Ceratocystis fimbriata Ellis & Halst., y especies de Fusarium de forma consecutiva con las tres estrategias metodológicas empleadas. La incidencia de la enfermedad fue del 16.6%, 15.2%, y 11.6% para las plantaciones de 2, 5 y 7 años, respectivamente. Los árboles enfermos en la plantación de 2 años se encontraron en las escalas 2, 4 y 5, mientras que en plantaciones de 5 y 7 años se ubicaron en las escalas 2, 3 y 5 de progreso de la enfermedad...(AU)

Teak plantations (Tectona grandis L. f.) in Ecuador are being affected by a complex disease of vascular wilt and dieback, with epidemic characteristics, without knowing the causal agent(s) so far. We proposed to describe the symptomatology of the disease and identify phytopathogenic fungi associated with diseased trees in the Ecuadorian Humid Tropic by morphophysiology. Three plantations of 2, 5 and 7 years of age were selected, in each three plots of 500 m2 were delimited. The symptomatologic description was made, evaluated the incidence and severity of the disease using a scale of five categories. By plot, three trees were dissected, whose tissues were taken to the laboratory, where three methodological strategies were used (wet chamber, carrot sandwiches, and potatodextrose-agar culture medium, PDA) to stimulate the expression of phytopathogens. In diseased trees, chlorosis, turgor loss, dry growth apices, emission of epicormic shoots in the stem, and fulminating wilt were detected. It was isolated and identified Ceratocystis fimbriata Ellis & Halst., and Fusarium species. consecutively with the three methodological strategies employed. The incidence of the disease was 16.6%, 15.2%, and 11.6% for plantations of 2, 5 and 7 years, respectively. The sick trees in the plantation of 2 years were found in scales 2, 4 and 5, while in plantations of 5 and 7 years they were located in scales 2, 3 and 5 of progress of the disease. ..(AU)

Total synthesis of cyclodepsipeptide Hikiamides A-C / 中国药科大学学报

@#Total synthesis of cyclodepsipeptide Hikiamides A-C was described. Fragment convergent condensation method was applied for the preparation of Hikiamides A-C, starting from Commercially available amino acid such as L-N-Boc-Phe-OH, L-N-Boc-Trp-OH, L-N-Cbz-Van-OH etc. Tripeptide fragments(compounds 5a/5b)and dipeptide fragments(compounds 8a/8b)were first prepared. The subsequent condensation of the resulted two fragments provided protected linear pentapetides(compounds 9a/9b/9c); Finally, the linear pentapetide was cyclized by a mixed condensing agents comprised of PyBOP and HBTU. Hikiamides A-C was obtained with total yields of 9%, 11% and 6. 5%, respectively. Compared with the natural source, this method has the advantages of low cost, convenient operation and high yield, which effectively solves the problem of low isolated yield of Hikiamides A-C from Fusarium sp.

Evaluación de la actividad fungicida e identificación de compuestos orgánicos volátiles liberados por Trichoderma viride / Evaluation of fungicidal activity and identification of volatile organic compounds released by Trichoderma viride

Resumen Los metabolitos secundarios producidos por hongos son ampliamente diversos en estructura y función, lo que provee una fuente de compuestos con actividad biológica para aplicaciones en agricultura, farmacia y procesamiento de alimentos. Entre los metabolitos secundarios se encuentran compuestos orgánicos volátiles (COVs) a los cuales se atribuye un papel determinante en la comunicación entre microorganismos. En este trabajo empleamos una cámara de ensayos comunicada por el espacio de cabeza para evaluar la actividad debida únicamente a COVs. Los resultados indican que los COVs liberados por T. viride afectan el crecimiento de los hongos fitopatógenos evaluados. En el caso de Fusarium sp. se afectaron los halos de crecimiento y para Colletotrichum gloeosporioides se observaron cambios morfológicos en su color. Para identificar los COVs responsables de esta actividad, se usaron 3 técnicas de extracción: Headspace dinámico (HSD), headspace estático (HSE) y extracción líquido-líquido (ELL) y el análisis por cromatografía de gases acoplada a espectrometría de masas (GCMS). Mediante el muestreo del HSD y HSE se encontraron alcoholes y lactonas, mientras que en ELL los compuestos mayoritarios fueron alcoholes y varios ácidos orgánicos. Entre los compuestos determinados por las tres técnicas se encuentran alcohol bencílico, alcohol 2-feniletílico, 6-pentil-2H-piran-2-ona y gama-butirolactona. Esta última identificada por primera vez en T. viride. La comparación de las tres técnicas de extracción permitió establecer que HSD es el método de extracción de COVs que mejor simula la situación presentada en la cámara de evaluación de actividad biológica, permitiendo así identificar los COVs responsables de la actividad antifúngica detectada.

Abstract The secondary metabolites produced by fungi widely vary in structure and function, providing a rich source of biologically active compounds with applications in farming, pharmacology and food processing. Volatile organic compounds (VOCs) are a biologically relevant class of secondary metabolites, since they are suspected of playing a crucial role in the communication between microorganisms. In this work, we use a test headspace chamber to evaluate the VOCs mediated antifungal activity of T. viride against Fusarium sp. and Colletotricum gloeosporiodes. We observed that VOCs produced by T. viride interact with both fungi affecting the growth halos of Fusarium sp. and modifying the colour of Colletotricum gloeosporiodes. The VOCs responsible for this activity were identified using three extraction techniques: Dynamical Headspace (DHS), Static Headspace (SHS) and liquid-liquid extraction (LLE), all of them analyzed via gas chromatography coupled to mass spectrometry (GCMS). DHS and SHS identified alcohols and lactones as VOCs, while with LLE we found a large number of alcohol components and several organic acids. All three techniques identified benzyl alcohol, 2-phenylethyl alcohol, 6-pentyl-2H-pyran-2-one and, for the first time associated to T. viride, gama-butirolactone. After comparison between these extraction techniques, we established that DHS provides the most accurate simulation of biological activity in the test chamber, which reflects in a reliable identification of the VCOs with antifungal activity.

Screening and Production of Manganese Peroxidase from Fusarium sp. on Residue Materials

In this study, we report the manganese peroxidase production ability from a Fusarium sp. strain using an inexpensive medium of agriculture residues of either rice straw or wood chips as carbon source. The highest manganese peroxidase activity on rice straw medium and on wood chips was 1.76 U/mL by day 9 and 1.91 U/mL by day 12, respectively.

Evaluación del crecimiento de cuatro especies del género Bacillus sp, primer paso para entender su efecto biocontrolador sobre Fusarium sp / Evaluation of growth of four species of the genus Bacillus sp, the first step to understand their biocontrol effect on Fusarium sp

Evaluar las condiciones de crecimiento de cuatro especies de Bacillus sp. nativas a escala de 10ml en Medio Mínimo de Sales (MMS) como primer paso para entender su acción biocontroladora contra Fusarium sp. Métodos. El procedimiento para evaluar el crecimiento de los aislamientos UCMC-TB1, UCMC-TB2, UCMC-TB3 y UCMC-TB4 se realizó utilizando espectrofotometría y recuento directo en placa y pruebas de antagonismo dual en placa para evaluar el efecto controlador contra Fusarium sp. Resultados. Se confirmó la identificación por pruebas bioquímicas de los cuatro aislamientos: Bacillus licheniformis, Bacillus subtilis, Bacillus pumilusy Bacillus cereus; todas las cepas presentaron antagonismo in vitro. El Bacillus subtilis fue la especie que demostró mayor capacidad antagónica (79,73%PICR) y las características más destacadas de esta cepa fueron su velocidad de crecimiento. El género Bacillus es uno de los más reportados para usar en el control biológico de hongos como Fusarium sp. el cual ataca un gran número de cultivos de interés económico para el sector agrícola en Colombia.

Objetive. Evaluate the conditions of growth of four species of native Bacillus sp. on the scale of in minimal medium 10ml Sales (MMS) as a first step to understand their biocontrol action against Fusarium sp. Methods. The procedure for evaluating the growth of UCMC-TB1, UCMC-TB2, UCMC-TB3 and TB4 UCMC-isolates was performed using spectrophotometry and direct plate count and dual antagonism tests to evaluate the effect against Fusarium sp. Results. Identification by biochemical tests of the four isolates were confirmed: Bacillus licheniformis, Bacillus subtilis, Bacillus pumilus and Bacillus cereus; all showed antagonism in vitro. Bacillus subtilis was the species that showed increased antagonistic capacity (79.73% PICR) and the main features of this strain were the speed of growth and death. The genus Bacillus is one of the most reported for use in the biological control of fungi such as Fusarium sp. It is attacking a large number of crops of economic interest to the agricultural sector in Colombia.

Fungal production of the anti-leukemic enzyme L-asparaginase: from screening to medium development / Produção fúngica da enzima antileucêmica L-asparaginase: da triagem ao desenvolvimento de um meio de cultivo

The treatment of acute lymphoblastic leukemia is challenging due to side effects, efficacy of the available drugs, and costs. Utilization of L-asparaginase as a therapeutic agent is essential to increase survival of patients. However, costs are elevated and the bacterial forms of the enzyme cause reactions that result in its inhibition by the immune system. Therapeutics alternatives may be searched among eukaryote producers, like fungi. Twelve strains of filamentous fungi were evaluated regarding expression of L-asparaginase activity. The profile of nitrogen assimilation and radial growth were determined for strains which showed higher production ratios. Three media were formulated after selection of the carbon source and carbon/nitrogen ratio that better induced L-asparaginase expression by Penicillium sp. and Fusarium sp. The enzyme activity produced in liquid media reached 8.3 U min.-1 mL-1 (Penicillium sp. T6.2) and 11.4 U min.-1 mL-1 (Fusarium sp.) after 72 hours of cultivation in Bacelar-1 medium. These data show that good producers can be found among fungi, and adjustment of productive processes may offer an alternative to implement eukaryote L-asparaginase production.

O tratamento da leucemia linfoblástica aguda é desafiador devido aos efeitos adversos, à eficácia dos fármacos disponíveis e aos custos envolvidos. A utilização de L-asparaginase como agente terapêutico é fundamental para aumentar a sobrevida do paciente. Porém, seu custo é elevado e as formas bacterianas da enzima causam reações que resultam na sua inibição pelo sistema imune. Alternativas terapêuticas podem ser buscadas entre produtores eucariontes, como os fungos. Doze linhagens de fungos filamentosos foram avaliadas quanto à expressão de atividade de L-asparaginase. O perfil de assimilação de nitrogênio e o crescimento radial foram determinados para as linhagens com maior razão de produção. Três meios foram formulados após a seleção da fonte de carbono e da razão carbono/nitrogênio que melhor induziram a expressão de L-asparaginase por Penicillium sp. e Fusarium sp. A atividade enzimática produzida em meio líquido alcançou 8,32 U min.-1 mL-1 (Penicillium sp. T6.2) e 11,45 U min.-1 mL-1 (Fusarium sp.) após 72 horas de cultivo no meio Bacelar-1. Esses dados mostram que bons produtores podem ser encontrados entre os fungos e que ajustes nos processos produtivos podem oferecer uma alternativa para a implementação da produção de L-asparaginase eucarionte.

Relationship between expression of sesquiterpene synthase gene and sesquiterpene content in artificial agarwood induced by Fusarium sp. A2 / 中国药学杂志

OBJECTIVE: To explore the expression of sesquiterpene synthase (gene sesqui-TPS) and dynamic change of sesquiterpene content in the resin-deposited parts of the trunk of Aquilaria sinensis (Lour.) Gilg. induced by Fusarium sp. A2. METHODS: Artificial agarwoods from Aquilaria sinensis were induced by Fusarium sp. A2 using pinhole instillation. The heartwood of Aquilaria sinensis without or with resin were extracted before induction and at 7 time points within one year after induction. The expression of sesqui-TPS was detected by quantitative Real-time PCR. And then the dynamic change of sesquiterpene content in the tissues were analyzed by gas chromatography-mass spectrometry (GC-MS). RESULTS: The relative expression of sesqui-TPS gene in the artificial agarwoods induced by Fusarium sp. A2 from 2 to 12 months were 10.85, 0.793 1, 6.484, 611.4, 5 800, and 4 211 respectively. Sesquiterpene secondary metabolites were not detected in the trunk at 2 months before artificial induction. Fourteen sesquiterpene were detected from 4 to 12 months, with relative percentages of 21.40%, 25.52%, 36.44%, 32.40% and 55.70% at each time point. CONCLUSION: Sesqui-TPS gene is extremely sensitive to Fusarium sp. A2 treatment and responds to late damage. The expression of sesqui-TPS gene lags behind the accumulation of sesquiterpene component, which would provide a foundation for studies on regulation action of function gene for sesquiterpene biosynthase pathway during the formation of agarwood resin in A. sinensis.

Incidência de fungos e germinação de sementes de feijão-caupi (Vigna unguiculata L. (Walp) tratadas com óleo de nim (Azadirachta indica A. Juss) / Incidence of fungi and germination of cowpea seeds (Vigna unguiculata L. (Walp) treated with neem oil (Azadirachta indica A. Juss)

Neste trabalho avaliou-se o efeito do óleo de nim no controle de fungos associados às sementes de feijão caupi e a influência deste produto na germinação de três cultivares (Serrinha, BR 17, e Maranhão). Foram preparadas diluições de 0,5; 1,0; 2,0; 4,0 g dm 3-do óleo de nim em água destilada e testemunha, só com água. Os fungos foram identificados pelo método do papel de filtro e a germinação das sementes foi avaliada considerando as informações das Regras para Análise de Sementes. Foram utilizadas sementes de três cultivares de feijão-caupi: a cultivar Serrinha, proveniente da cidade de Timon-MA, a cultivar Maranhão, da cidade de Viana - MA, e a cultivar BR 17, obtida junto à Embrapa Meio Norte, na cidade de Teresina-PI. O crescimento de Fusarium sp. nas cultivares Maranhão e Serrinha foi reduzido em 52 e 53%, respectivamente e o índice de redução de Aspergillus sp. foi de 14 e 20% nas mesmas cultivares. Em relação aos fungos M. phaseolina e Phoma sp., observa-se que não foram inibidos em nenhuma das três cultivares. No que se refere à germinação das sementes nota-se que na cultivar Maranhão houve aumento no índice da germinação de 13 e 17,5% em relação à testemunha e, na cultivar Serrinha, somente a concentração 0,5% diferiu da testemunha com redução no índice de germinação de 6,49%. Conclui-se que o óleo de nim reduz a incidência de Fusarium sp. e Aspergillus sp. e é indiferente na redução de M. phaseolina e Phoma sp. O índice de germinação aumentou na cultivar Maranhão e diminuiu na cultivar Serrinha.

This study aimed to evaluate the effect of neem oil on germination and fungi incidence on the seeds of three cowpea cultivars (Serrinha, BR 17 and Maranhão). Dilutions of 0.5; 1.0; 2.0, 4.0 g dm-3 of neem oil were prepared in water. The fungi incidence was evaluated by the filter paper test, and the germination was evaluated according to the Rules for Seeds Testing ("Regras para Análise de Sementes," in Portuguese). Seeds of three cowpea cultivars were used: Serrinha and Maranhão, from the cities of Timon and Viana, respectively, state of Maranhão, Brazil, and BR 17, from Embrapa Meio Norte (Terezina, state of Piaí, Brazil). The growth of Fusarium sp. on the seed of the Maranhão and Serrinha cultivars was reduced in 52 and 53%, respectively, and the reduction rate of Aspergillus sp. was 14 and 20%, on the same cultivars. However, the neem oil did not inhibit the growth of the fungi Macrophomina phaseolina and Phoma sp. in any of the three cultivars. With regard to the seed germination, an increase of 13 and 17.5% was observed in the Maranhão cultivar compared to control, while for the Serrinha cultivar, only the 0.5% concentration differed from the control, reducing the germination rate by 6.49%. We conclude that the neem oil was effective in controlling Aspergillus sp. and Fusarium sp. On the other hand, it was ineffective against Phoma sp. and M. phaseolina. The germination increased in the Maranhão cultivar and decreased in the Serrinha cultivar.

Determinación de metabolitos secundarios a partir de Bacillus subtilis efecto biocontrolador sobre Fusarium sp / Determination of secondary metabolites from Bacillus subtilis with effect biological control on Fusarium sp

El uso de agentes de control biológico es una alternativa eficaz para el tratamiento de las enfermedades en plantas, contribuyendo en la disminución del uso de pesticidas químicos. Microorganismos del género Bacillus se han convertido en el centro de interés por su producción de metabolitos de tipo secundario, con propiedades antifúngicas, supresores efectivos contra diversos Fitopatógenos como Fusarium, Pythium, Phytophthora y Rhizoctonia. El objetivo del presente estudio fue identificar la presencia de metabolitos secundarios obtenidos por fermentación en estado líquido a partir de una cepa de Bacillus subtilis, los cuales fueron analizados mediante cromatografía de alta resolución (HPLC). Se confirmó su efecto biocontrolador sobre Fusarium sp por pruebas de excavación en placa. Se identificó el antibiótico Iturina A, con una concentración aproximada de 151.805 mg/l y las pruebas de antagonismo in vitro expresaron un porcentaje de 70 a 100% de inhibición de crecimiento sobre Fusarium sp. Se espera a futuro identificar la presencia de otros metabolitos de tipo secundario, de importancia en fitosanidad, como la producción de surfactina y fengicina.

The use of microorganisms for biological control of plants diseases in an effective alternative that reduce pesticides use that affect soil fertility. Bacillus genus has become a point of interest due the production of secondary metabolites with antifungal properties effective against several phytopathogenics such as Fusarium, Pythium, Phytophthora and Rhizoctonia. The aim of this study was to identify the presence of secondary metabolites produced by liquid fermentation from Bacillus subtilis, analyzed by High-performance liquid chromatography (HPLC), and confirm its biocontrol effect on Fusarium sp. The antibiotic iturin A was identified, with a concentration around 151,805 mg/l. In vitro antagonism tests showed 70 to 100% growth inhibition of Fusarium sp. In the near future is expected to identify the existence of other secondary metabolites with possible significant effect on the plant protection, such as surfactin and fengycin.

EVALUACIÓN DEL ANTAGONISMO Y MULTIPLICACIÓN DE Trichodermasp. EN SUSTRATO DE PLÁTANO EN MEDIO LÍQUIDO ESTáTICO / Evaluation Of Antagonism And Multiplication The Trichodermasp. In The Middle Static Liquid Banana Substrate

Se evaluó la capacidad antagónica de nueve aislados del hongo Trichoderma sp. proveniente de la colección de cepas del Laboratorio de Fitopatología de la Universidad de Córdoba, Colombia y su producción de esporas en medios de cultivo líquido estático, a través de pruebas in vitro de antagonismo, utilizando dos hongos fitopatógenos: Fusarium sp. y Rhizoctonia sp.; esta prueba permitió seleccionar el aislado con la mayor actividad antagónica, para así ajustar la producción de esporas mediante un proceso de fermentación en estado líquido en condición estática mediante procesos de buferización y sin buferización con fosfato 0,2N, utilizándose como sustrato principal harina de plátano (HP) 5%, además de complementos nutricionales que constituyeron los tratamientos: HPM (solución de melaza 5%), HPL (solución de levadura granulada al 2%), HPU (solución de urea 0,1%), y como testigo PGL (papa glucosa líquida). En los ensayos de antagonismo se seleccionó el aislado C2 de Trichoderma sp. por presentar la mayor capacidad antagónica frente al hongo Fusarium sp., con un porcentaje de inhibición del 78,30% y reportando un índice 4 de antagonismo, en los procesos de producción de esporas el tratamiento HPL (harina de plátano más levadura sin buffer) se destacó por su favorable producción de conidias, con una concentración de 1,1 x 10(9) conidias/mL. Los procesos de buferización se diferenciaron significativamente, demostrando que la variable buffer influyó en la producción de conidias, los medios que se amortiguaron mostraron una producción de 1,01 x 10(9) conidias/mL, con respecto a los que no se amortiguaron 6,3 x 10(8) conidias/mL.

The antagonistisc ability of nine isolated natives fungi Trichoderma sp from the collection of strains at Laboratory of phytopathology at University of Cordoba, Colombia was assessed so as its production of spores in crop liquid static medium, cross the in vitro proof antagonism using two phytopathogenic fungi: Fusarium sp. and Rhizoctonia sp., this proof let select the isolated with the major antagonistic activity and adjust the production of spores through fermentation process in liquid static by means of buffer and without buffer with phosphate 0,2 N, being used as principal substrate plantain flour (HP) 5%, besides of nutritional supplements that formed the trataments: HPM (molasses solution 5%), HPL (granulated yeast solution at 2%), HPU (urea solution 0.1%), and as witness PGL (potato glucose liquid). In the test of antagonism was selected the isolated C2 of Trichoderma sp. by present the major antagonistic ability in front of the fungi Fusarium sp., with a inhibition percentage at 78,30% and reporting a index 4 of antagonism, in the process of spores production, the tratament HPL (plantain flour plus yeast without buffer) stressed for the favorable production of conidias, with a concentration of 1,1 x 10(9) conidias/mL. The buffer process were significant differentiated, showing that the variable buffer influenced in the production of conidias, the mediums that shocked in the production show 1,01 x 10(9) conidias/mL, Ïwith respect at don’t shocked 6,3 x 10(8) conidias/mL.

Protocolo para la formación de microtubérculos de ñame (Dioscorea alata L) en sistema de inmersión temporal / A protocol for yam (Dioscorea alata L) microtuber formation in temporary immersion system

Con el propósito de desarrollar un protocolo para la formación de microtubérculos en el clon de ñame Pacala Duclos (Dioscorea alata L) en sistema de inmersión temporal, que pudiera ser usado como alternativa para la propagación de esta especie, se deinieron como objetivos de trabajo determinar el efecto del tiempo y la frecuencia de inmersión, así como la inluencia del volumen de medio de cultivo por planta cultivada in vitro. Con el empleo de 15 min de inmersión y una frecuencia de inmersión cada 6 horas, se alcanzaron los mejores resultados en cuanto al número de microtubérculos formados por planta. Con este tiempo y frecuencia de inmersión los microtubérculos presentaron la mayor masa fresca y seca, así como el mayor diámetro. Además, a las 18 semanas de cultivo se obtuvo el mayor número total de microtubérculos por sistema y el mayor número de microtubérculos aprovechables como material vegetal de propagación. En cuanto al volumen de medio de cultivo por planta, con 60 ml de medio de cultivo por planta in vitro se alcanzó el mayor número de microtubérculos aprovechables, los cuales presentaron el contenido más alto de materia seca. Los microtubérculos obtenidos en este tipo de sistema de inmersión temporal presentaron una masa fresca superior a 2,40 gMF, lo cual podría permitir su uso como material de plantación directo a campo

The following working objectives were deined for developing a protocol for ´Pacala Duclos´ yam clone (Dioscorea alata L) microtuber formation in temporary immersion systems (TIS): time effect, immersion frequency and culture medium volume inluence per in vitro cultivated plant. The results led to deining that the highest performance regarding microtuber number formed per plant was achieved with a 15-minute immersion time and six-hourly immersion frequency; the microtubers presented the greatest dry and fresh weight and largest diameter at such immersion time and frequency. Furthermore, the highest total number of microtubers per system and the largest number of microtubers usable for planting (vegetal propagation) material were obtained after 18 weeks’ culture. Regarding culture medium volume per plant, the greatest amount of usable microtubers was achieved with 60 ml per in vitro plant, microtubers presenting the highest dry matter content. As microtubers obtained in this type of TIS had fresh weights higher than 2.40 gFW they could be used as direct planting material in ield conditions

Evaluación de métodos para la conservación de hongos fitopatógenos del ñame (Dioscorea sp) / Evaluating methods for preserving yam (Dioscorea sp) phytopathogenic fungii

Un elemento esencial en la investigación con microorganismos fitopatógenos es su conservación y uso seguro.Desde este punto de vista, en este estudio se evaluaron métodos de conservación de hongos que atacanel ñame, empleando como factores de respuesta el potencial de viabilidad, y la estabilidad y presencia o ausenciade cambios en las características macro y microscópicas. Como resultado del trabajo se proponen los métodos más adecuados para los géneros Colletotrichum y Fusarium, hongos causantes de las mayores pérdidasen las plantaciones de ñame en la Costa Caribe colombiana. Las cepas utilizadas en este estudio provienen de las colecciones de la Universidad de Sucre, del Instituto de Biotecnología de la Universidad Nacional de Colombia (IBUN) y de una donación de la doctora Lucía Afanador de la Universidad Nacional, Sede Medellín.Estas fueron sometidas a diferentes métodos de conservación, entre ellos criopreservación, liofilizacióny cultivo periódico con y sin aceite mineral. Los resultados obtenidos permitieron elegir la criopreservacióncomo el método más eficiente para la conservación de la colección, y el cultivo periódico con aceite mineralcomo método alternativo y complementario. Estos minimizan el riesgo de pérdida del material biológico y brindan condiciones de manejo que conservan las características biológicas bajo estudio desde campos comola microbiología, la bioquímica y la biología molecular, entre otros.

An essential element in phytopathogenic microorganism research is their preservation and safe use. The purposeof this study was to evaluate methods for preserving fungi producing diseases in yam, using potential viability, stability and the presence or absence of macro- and microscopic characteristic changes as response factors. More suitable methods for Colletotrichum and Fusarium genera were proposed as a result of the work; these are fungi causing the greatest losses in yam plantations on the Colombian Caribbean Coast. The strains used in this study came from collections kept at the University of Sucre and the Universidad Nacional de Colombia’s Institute of Biotechnology (IBUN) in Bogota and a donation from Dr Lucia Afanador from the Universidad Nacional in Medellín. These strains were subjected to different preservation methods, including cryopreservation, lyophilisation and periodic culture with and without mineral oil. The results led to choosing cryopreservation as the most efficient method for preserving the collection and the periodic culture withmineral oil as an alternative and complementary method. These minimised the risk of biological material loss and provided handling conditions conserving the biological characteristics of the fungi being studied from the fields of microbiology, biochemistry and molecular biology.

Fusarium sp in severe contact lens related fungal keratitis / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To report a rare case of severe contact lens related fungal keratitis due to fusarium sp, which not only was successfully treated with therapeutic penetrating keratoplasty but also aided in the confirmation of diagnosis. METHODS:Case report.RESULTS: A 39-year-old private clerk Malay lady who wore extended wear soft contact lens for the past 18 years, presented with acute right eye pain and redness for 10 days duration. Ocular examination showed multiple round feathery paracentral corneal ulcers with presence of minimal hypopyon. Clinical diagnosis of presumed fungal keratitis was made. She was treated with broad spectrum topical antibiotics and antifungal agents after repeated corneal scrapping was negative either for fungi or for the bacteria. However, she developed deterioration of the right eye keratitis. Other topical and systemic antifungal agents were instituted. Unfortunately the right corneal ulcer became further deteriorating. Finally a therapeutic penetrating keratoplasty has done in order to preserve the globe and limit the infection after one and a half months of presentation. The diagnosis and the etiology agent were only confirmed based on histopathological examina-tion and polymerase chain reaction (PCR) from corneal button revealed fusarium sp.CONCLUSION:This case highlights the rare case of fusarium sp as an etiology of severe contact lens related fungal keratitis. This case also illustrates the challenge in managing fungal keratitis. Therapeutic penetrating keratoplasty is the ultimate choice in controlling further infection and perserving the globe.