Influence of microbial consortia on the incidence of grey mold (Botrytis cinerea) in strawberry (Monterey variety)

Botrytis cinerea, the causal agent of grey mold disease, is one of the most destructive pathogens of strawberry crops, both in vegetative development and postharvest. The control of this pathogen is complex due to its aggressiveness and ability to attack and infect various plant tissues and is mainly based on chemical control; however, the incorrect use of pesticides, mainly due to overdosing, causes the presence of traces of these agrochemicals in the fruits, as well as the selection of pathogen resistance to fungicides, making it a risk to human health and the environment. The objective of the study was to use biological regulation strategies, with the application of microbial consortia made up of mycorrhizal fungi, antagonistic bacteria and Trichoderma harzianum, as an alternative for the management of grey mold in strawberry crops (Monterey variety) under field conditions. Treatments T4 (mycorrhizal fungi), T8 (mycorrhizal fungi, antagonistic bacteria and T. harzianum) and T2 (T. harzianum) presented the lowest incidence of the pathogen with 2.6, 3.1 and 3.6 %, respectively, compared to control plants with 16.6%. The influence of all biological treatments on the regulation of B. cinerea was greater than the control.

Botrytis cinerea, el agente causal de la enfermedad del moho gris, es uno de los patógenos más destructivos del cultivo de fresa, tanto en el desarrollo vegetativo como en poscosecha. El control de este patógeno es complejo, debido a su agresividad y capacidad de atacar e infectar diversos tejidos de la planta y se basa, principalmente, en el control químico; sin embargo, el uso incorrecto de plaguicidas, principalmente por sobredosificación, provoca la presencia de trazas de estos agroquímicos en los frutos, así como la selección de resistencia del patógeno a los fungicidas, convirtiéndolo en un riesgo para la salud humana y el ambiente. El objetivo del estudio fue utilizar estrategias de regulación biológica, con la aplicación de consorcios microbianos, conformados por hongos micorrícicos, bacterias antagonistas y Trichoderma harzianum, como alternativa para el manejo del moho gris, en cultivos de fresa (variedad Monterey), en condiciones de campo. Los tratamientos T4 (hongos micorrízicos), T8 (hongos micorrízicos, bacterias antagonistas y T. harzianum) y T2 (T. harzianum) presentaron la menor incidencia del patógeno, con 2,6, 3,1 y 3,6 %, respectivamente, en comparación con las plantas control, con 16,6 %. La influencia de todos los tratamientos biológicos en la regulación de B. cinerea fue mayor respecto al control.

Antifungal efficacy of Moringa oleifera leaf and seed extracts against Botrytis cinerea causing gray mold disease of tomato (Solanum lycopersicum L. ) / Eficácia antifúngica de extratos de folha e de semente de Moringa oleifera contra Botrytis cinerea causador da doença do molde cinza de tomate (Solanum lycopersicum L. )

Abstract Drawbacks associated with the use of chemical fungicides to control plant pathogenic fungi such as Botrytis cinerea stimulate the need for alternatives. Therefore, the present study was carried out to determine the antifungal potentials of Moringa oleifera extracts against B. cinerea. Phytochemical analysis using qualitative chemical tests revealed the presence of huge amount of crucial phytochemicals compounds like phenolic compounds, alkaloids and saponins in the M. oleifera leaf extract. Antifungal bioassay of the crude extracts indicated better mycelial growth inhibition by methanol leaf extract (99%). The minimum inhibitory concentration (MIC) was 5 mg/ml with 100% spore germination inhibition and minimum fungicidal concentration (MFC) was 10 mg/ml with 98.10% mycelial growth inhibition using broth micro dilution and poisoned food techniques. Gas chromatography-mass spectrometry (GC-MS) analysis led to the identification of 67 volatile chemical compounds in the leaf extract with 6-decenoic acid (Z)- (19.87%) was the predominant compound. Further chemical elucidation of the crude extracts performed by liquid chromatography with tandem mass spectrometry (LC-MS/MS) showed the presence of non-volatile chemical compounds, mostly flavones, flavonoids and phenolic acids (i.e. quercetin and kaempferol). Scanning electron microscopy and transmission electron microscopy analysis showed positive effect of M. oleifera leaf extract on the treated conidia and mycelium of B. cinerea. Findings revealed that irreversible surface and ultra-structural changes with severe detrimental effects on conidia and mycelium morphology compared to control treatment. Overall findings suggested that M. oleifera leaf extract is a promising candidate for biological control of fungal pathogens, thus limiting overdependence on chemical fungicides.

Resumo As desvantagens associadas ao uso de fungicidas químicos para controlar fungos fitopatogênicos, como Botrytis cinerea, estimulam a necessidade de alternativas. Portanto, o presente estudo foi realizado para determinar o potencial antifúngico de extratos de Moringa oleifera contra B. cinerea. A análise fitoquímica usando testes químicos qualitativos revelou a presença de uma grande quantidade de compostos fitoquímicos cruciais, como compostos fenólicos, alcaloides e saponinas no extrato da folha de M. oleifera. O bioensaio antifúngico dos extratos brutos indicou melhor inibição do crescimento micelial pelo extrato de folhas de metanol (99%). A concentração inibitória mínima (MIC) foi de 5 mg/mL com 100% de inibição da germinação de esporos e a concentração fungicida mínima (MFC) foi de 10 mg/mL com 98,10% de inibição do crescimento micelial usando microdiluição em caldo e técnicas de alimentos envenenados. A análise por cromatografia gasosa-espectrometria de massa (GC-MS) levou à identificação de 67 compostos químicos voláteis no extrato da folha, sendo o ácido 6-decenoico (Z) (19,87%) o composto predominante. Elucidação química adicional dos extratos brutos realizada por cromatografia líquida com espectrometria de massa em tandem (LC-MS/MS) mostrou a presença de compostos químicos não voláteis, principalmente flavonas, flavonoides e ácidos fenólicos (ou seja, quercetina e kaempferol). As análises de microscopia eletrônica de varredura e microscopia eletrônica de transmissão mostraram efeito positivo do extrato de folhas de M. oleifera sobre os conídios e micélios tratados de B. cinerea. Os resultados revelaram a superfície irreversível e alterações ultraestruturais com graves efeitos prejudiciais sobre os conídios e a morfologia micelial, em comparação com o tratamento de controle. Os resultados gerais sugeriram que o extrato da folha de M. oleifera é um candidato promissor para o controle biológico de patógenos fúngicos, limitando assim a dependência excessiva de fungicidas químicos.

Prohexadione-calcium on downy mildew and botrytis bunch rot epidemiology, and yield and technological and phenolic parameters of the Merlot vine cultivar in the highland region of southern Brazil / Efeitos da prohexadiona de cálcio na epidemiologia do mildio e podridão de botrytis e no desempenho vitícola da cultivar de videira Merlot em região de altitude do sul do Brasil

ABSTRACT: Prohexadione-calcium (ProCa) is a gibberellin biosynthesis inhibitor and the objective of this study was to evaluate the effect of ProCa on the downy mildew (DM) and Botrytis bunch rot (BBR) epidemiology, and the yield and technological and phenolic parameters of grape Merlot cultivar. Experiments were carried out in a commercial vineyard in São Joaquim Municipality/SC, Southern Brazil, during the 2017-2018 and 2018-2019 growing seasons. ProCa was applied at four doses and three phenological stages: A) 0 g ha−1 (control); B) 1000 g ha−1 (inflorescence fully developed); C) 500 + 500 g ha−1 (inflorescence fully developeted and full flowering); D) 500 + 500 + 500 g ha−1 (inflorescence fully developed, full flowering, and berries pea-sized). DM and BBR incidence and severity were quantified weekly from the first symptom appearance until harvest, and their epidemiology was compared according to: a) the beginning of symptom appearance; b) the time to reach the maximum disease incidence and severity; c) the maximum value of disease incidence and severity; d) the area under the disease progress curve. In general, there were significant differences in the ProCa doses for all epidemiologic parameters of DM and BBR compared with the control plot; however, there was no significant difference among the ProCa doses. The principal epidemiological variables that differentiated the effect of ProCa on the DM and BBR control were the Smax and AUSDPC. Some yield and technological and phenolic parameters were negatively affected by different doses of ProCa, but it was still a good option for DM and BBR control in highland region of southern Brazil during the 2017-2018 and 2018-2019 growing seasons.

RESUMO: A prohexadiona-cálcio (ProCa) é um inibidor da biossíntese de giberelina e o objetivo desse estudo foi avaliar o efeito do ProCa na epidemiologia do míldio da videira (MV) e da podridão de Botrytis (PB) e no desempenho vitícola da cultivar de videira Merlot. Experimentos foram realizados em um vinhedo comercial no município de São Joaquim/SC, Sul do Brasil, durante as safras 2017-2018 e 2018-2019. A ProCa foi aplicada em quatro doses e três estágios fenológicos: A) 0 g ha-1 (controle); B) 1000 g ha-1 (inflorescência totalmente desenvolvida); C) 500 + 500 g ha-1 (inflorescência totalmente desenvolvida e floração completa); D) 500 + 500 + 500 g ha-1 (inflorescência totalmente desenvolvida, floração completa e baga tipo ervilha). A incidência e severidade de MV e PB foram quantificadas semanalmente a partir do aparecimento dos primeiros sintomas até a colheita e a epidemiologia das doenças foram comparadas de acordo com: a) o início do aparecimento dos sintomas; b) tempo para atingir a máxima incidência e severidade da doença; c) valor máximo da incidência e severidade da doença; d) área abaixo da curva de progresso da doença. Em geral, houve diferenças significativas na dose de ProCa para todos os parâmetros epidemiológicos de MV e PB em comparação com o controle; no entanto, não houve diferença significativa entre as doses de ProCa. As principais variáveis ​​epidemiológicas que diferenciaram o efeito da ProCa no controle do MV e PB foram o Smax e o AUSDPC. Algumas variáveis vitícolas da cultivar Merlot foram afetados negativamente por diferentes doses de ProCa, mas ainda foi uma boa opção o uso da ProCa para o controle do MV e PB em região de altitude do sul do Brasil durante as safras 2017-2018 e 2018-2019.

Exocyst subunit BcSec3 regulates growth, development and pathogenicity in Botrytis cinerea

Botrytis cinerea is a saprophytic plant pathogenic fungus that can infect a variety of crops and cause gray mold,which leads to huge losses worldwide. The role of exocyst in fungal pathogenicity is being revealed. In thisstudy, homologous recombination technology was used to knock out the exocyst subunit BcSec3 of B. cinerea,and it was found that the BcSec3 subunit plays a crucial role in the growth and pathogenicity of B. cinerea.Compared with the wild-type strain B05.10, the mycelial growth ability of the BcSec3 deletion strain wasreduced by up to 49.8%, the conidia production capacity of the deletion strain was severely lost, and nosclerotia was formed. The polygalacturonase, is one of plant cell wall hydrolases, whose activity in BcSec3deletion strain was significantly reduced. In the tomato leaves infection assay in vitro, the lesion area caused bythe BcSec3 deletion strain was only 20% of the wild type after 5 days of infection. Observation by lightmicroscope showed that the morphology of BcSec3 deletion strain mycelium was significantly changed, themycelium became thinner and deformed, and the polarity growth was not obvious. Further observation withlaser confocal microscopy and transmission electron microscopy was conducted. It was found that comparedwith the wild type, the number of vesicles in BcSec3 deleted cells reduced and localization and distribution ofvesicles changed. In mutant cell, vesicles relatively concentrated in the cytoplasm, while in wild-type cellmainly concentrated inside the cell membrane. These evidences indicate that the exocyst subunit BcSec3 playsan important role in the growth, development and pathogenicity of B. cinerea.

Diagrammatic scale for measuring severity of gray mould in thornless Castilla blackberry (Rubus glaucus Benth) / Escala diagramática para medir a severidade do mofo cinzento em amora de Castilla (Rubus glaucus Benth) sem espinhos

ABSTRACT: Gray mould, caused by the fungus Botrytis cinerea Pers., is a disease that largely affects the crops of Rubus glaucus Benth. (Castilla blackberry) in Colombia. In spite of the economic losses that it causes in the production of Castilla blackberry at national level, a standardized method to quantify the disease severity caused by this fungus in the fruits has not yet been reported. In the present work, a diagrammatic scale was prepared to assess gray mould severity in thornless fruits of R. glaucus. The proposed scale showed the levels of 5, 10, 20, 40, 60, 80, and 100%. Photographic images were obtained for each of these levels, which were processed using the ImageJ software. The scale was validated by 13 evaluators who assessed affected fruits with and without the scale. The precision and accuracy of each evaluator was determined by simple linear regression between actual and estimated severity. The evaluators showed better precision, accuracy, and reproducibility in the assessments performed with the scale. The proposed scale is appropriate to estimate the severity of gray mould in R. glaucus fruits.

RESUMO: O mofo cinzento, causado pelo fungo Botrytis cinerea Pers., é uma doença que afeta amplamente as culturas de Rubus glaucus Benth. (Amora preta) na Colômbia. Apesar das perdas econômicas causadas na produção de amora preta em nível nacional, ainda não foi relatado um método padronizado para quantificar a severidade da doença causada por esse fungo nos frutos. No presente trabalho, uma escala diagramática foi preparada para avaliar a severidade do mofo cinza em frutos sem espinho de R. glaucus. A escala proposta apresentou os níveis de 5, 10, 20, 40, 60, 80 e 100%. Imagens fotográficas foram obtidas para cada um desses níveis, processadas com o software ImageJ. A escala foi validada por 13 avaliadores que analisaram os frutos afetados com e sem a escala. A precisão e exatidão de cada avaliador foram determinadas por regressão linear simples entre a severidade real e a estimada. Os avaliadores mostraram melhor precisão, exatidão e reprodutibilidade nas avaliações realizadas com a escala. A escala proposta é apropriada para estimar a severidade do mofo cinza em frutos de R. glaucus.

Screening and Evaluation of Yeast Antagonists for Biological Control of Botrytis cinerea on Strawberry Fruits

Gray mold (Botrytis cinerea) is one of the most common diseases of strawberries (Fragaria × ananassa Duchesne) worldwide. Although many chemical fungicides are used for controlling the growth of B. cinerea, the risk of the fungus developing chemical resistance together with consumer demand for reducing the use of chemical fungicides have necessitated an alternative method to control this pathogen. Various naturally occurring microbes aggressively attack plant pathogens and benefit plants by suppressing diseases; these microbes are referred to as biocontrol agents. However, screening of potent biocontrol agents is essential for their further development and commercialization. In this study, 24 strains of yeast with antagonistic ability against gray mold were isolated, and the antifungal activity of the volatile and diffusible metabolites was evaluated. Putative mechanisms of action associated with the biocontrol capacity of yeast strains against B. cinerea were studied through in vitro and in vivo assays. The volatile organic compounds produced by the Galactomyces candidum JYC1146 could be useful in the biological control of plant pathogens and therefore are potential alternative fungicides with low environmental impact.

Antifungal efficacy of Moringa oleifera leaf and seed extracts against Botrytis cinerea causing gray mold disease of tomato (Solanum lycopersicum L.)

Abstract Drawbacks associated with the use of chemical fungicides to control plant pathogenic fungi such as Botrytis cinerea stimulate the need for alternatives. Therefore, the present study was carried out to determine the antifungal potentials of Moringa oleifera extracts against B. cinerea. Phytochemical analysis using qualitative chemical tests revealed the presence of huge amount of crucial phytochemicals compounds like phenolic compounds, alkaloids and saponins in the M. oleifera leaf extract. Antifungal bioassay of the crude extracts indicated better mycelial growth inhibition by methanol leaf extract (99%). The minimum inhibitory concentration (MIC) was 5 mg/ml with 100% spore germination inhibition and minimum fungicidal concentration (MFC) was 10 mg/ml with 98.10% mycelial growth inhibition using broth micro dilution and poisoned food techniques. Gas chromatographymass spectrometry (GC-MS) analysis led to the identification of 67 volatile chemical compounds in the leaf extract with 6-decenoic acid (Z)- (19.87%) was the predominant compound. Further chemical elucidation of the crude extracts performed by liquid chromatography with tandem mass spectrometry (LC-MS/MS) showed the presence of non-volatile chemical compounds, mostly flavones, flavonoids and phenolic acids (i.e. quercetin and kaempferol). Scanning electron microscopy and transmission electron microscopy analysis showed positive effect of M. oleifera leaf extract on the treated conidia and mycelium of B. cinerea. Findings revealed that irreversible surface and ultra-structural changes with severe detrimental effects on conidia and mycelium morphology compared to control treatment. Overall findings suggested that M. oleifera leaf extract is a promising candidate for biological control of fungal pathogens, thus limiting overdependence on chemical fungicides.

Resumo As desvantagens associadas ao uso de fungicidas químicos para controlar fungos fitopatogênicos, como Botrytis cinerea, estimulam a necessidade de alternativas. Portanto, o presente estudo foi realizado para determinar o potencial antifúngico de extratos de Moringa oleifera contra B. cinerea. A análise fitoquímica usando testes químicos qualitativos revelou a presença de uma grande quantidade de compostos fitoquímicos cruciais, como compostos fenólicos, alcaloides e saponinas no extrato da folha de M. oleifera. O bioensaio antifúngico dos extratos brutos indicou melhor inibição do crescimento micelial pelo extrato de folhas de metanol (99%). A concentração inibitória mínima (MIC) foi de 5 mg/mL com 100% de inibição da germinação de esporos e a concentração fungicida mínima (MFC) foi de 10 mg/mL com 98,10% de inibição do crescimento micelial usando microdiluição em caldo e técnicas de alimentos envenenados. A análise por cromatografia gasosa-espectrometria de massa (GC-MS) levou à identificação de 67 compostos químicos voláteis no extrato da folha, sendo o ácido 6-decenoico (Z) (19,87%) o composto predominante. Elucidação química adicional dos extratos brutos realizada por cromatografia líquida com espectrometria de massa em tandem (LC-MS/MS) mostrou a presença de compostos químicos não voláteis, principalmente flavonas, flavonoides e ácidos fenólicos (ou seja, quercetina e kaempferol). As análises de microscopia eletrônica de varredura e microscopia eletrônica de transmissão mostraram efeito positivo do extrato de folhas de M. oleifera sobre os conídios e micélios tratados de B. cinerea. Os resultados revelaram a superfície irreversível e alterações ultraestruturais com graves efeitos prejudiciais sobre os conídios e a morfologia micelial, em comparação com o tratamento de controle. Os resultados gerais sugeriram que o extrato da folha de M. oleifera é um candidato promissor para o controle biológico de patógenos fúngicos, limitando assim a dependência excessiva de fungicidas químicos.

Entomopathogenic Fungi as Dual Control Agents against Both the Pest Myzus persicae and Phytopathogen Botrytis cinerea

The green peach aphid (Myzus persicae), a plant pest, and gray mold disease, caused by Botrytis cinerea, affect vegetables and fruit crops all over the world. To control this aphid and mold, farmers typically rely on the use of chemical insecticides or fungicides. However, intensive use of these chemicals over many years has led to the development of resistance. To overcome this problem, there is a need to develop alternative control methods to suppress populations of this plant pest and pathogen. Recently, potential roles have been demonstrated for entomopathogenic fungi in endophytism, phytopathogen antagonism, plant growth promotion, and rhizosphere colonization. Here, the antifungal activities of selected fungi with high virulence against green peach aphids were tested to explore their potential for the dual control of B. cinerea and M. persicae. Antifungal activities against B. cinerea were evaluated by dual culture assays using both aerial conidia and cultural filtrates of entomopathogenic fungi. Two fungal isolates, Beauveria bassiana SD15 and Metarhizium anisopliae SD3, were identified as having both virulence against aphids and antifungal activity. The virulence of these isolates against aphids was further tested using cultural filtrates, blastospores, and aerial conidia. The most virulence was observed in the simultaneous treatment with blastospores and cultural filtrate. These results suggest that the two fungal isolates selected in this study could be used effectively for the dual control of green peach aphids and gray mold for crop protection.

Relationship between production, nematodes and "redness" in strawberries / Relação entre produção, nematoide e o sintoma de "vermelhão" em morangueiros

ABSTRACT: In recent years "redness" has increasingly appeared in strawberry plants with leaves taking on a reddish color. No causal agent has been associated with plants. Since strawberries presented problems due to the incidence of nematodes, the purpose of this study was to look at the relationship between production, resistance to the Meloidogyne hapla nematode and the "redness" symptom in strawberry cultivars. Two experiments were performed, both with the 'Camino Real', 'Festival', 'Oso Grande', 'Albion' and 'Camarosa' cultivars. The first experiment was performed in the field, where the following were evaluated: strawberry production, fruit quality, macro and micronutrient contents in fruit and leaves, percentage of plant survival, incidence of nematodes, quantity of eggs in the roots and juveniles in the soil, and the incidence of Botrytis cinerea . In the second experiment, the strawberries were transplanted into pots and filled with pinus bark-based commercial substrate. Half the pots were inocculated with Meloidogyne hapla . Cultivars presented differences in fruit production and also in the incidence of "redness". Lowest performance in production was related to the high incidence of the nematode Meloidogyne hapla. 'Oso Grande' and 'Albion' presented nematode-resistant behavior. It was possible find a relationship between the incidence of the Meloidogyne hapla nematode, and the incidence of "redness" only 'Camino Real' cultivar.

RESUMO: Nos últimos anos, vem aumentando o aparecimento do "vermelhão" nos morangueiros, que ficam com as folhas avermelhadas. Nenhum agente causal foi associado às plantas. Devido aos plantios de morangueiros apresentarem problemas pela incidência de nematoide, o objetivo do presente trabalho foi verificar a relação entre produção, resistência ao nematoide Meloidogyne hapla e o sintoma de "vermelhão" em cultivares de morangueiro. Foram realizados dois experimentos, ambos com as cultivares 'Camino Real', 'Festival', 'Oso Grande', 'Albion' e 'Camarosa'. O primeiro experimento foi realizado a campo, onde se avaliaram a produção de morangos, qualidade dos frutos, teores de macro e micronutrientes em frutos e folhas, porcentagem de sobrevivência das plantas, incidência de nematoides, quantidade de ovos nas raízes e juvenis no solo e a incidência de Botrytis cinerea. No segundo experimento, os morangueiros foram transplantados em vasos e preenchidos com substrato comercial a base de casca de pinus. Metade dos vasos foi inoculada com Meloidogyne hapla. As cultivares apresentaram diferenças na produção de frutos e também na incidência de "vermelhão". O menor desempenho produtivo relaciona-se com a alta incidência de nematoide Meloidogyne hapla. 'Oso Grande' e 'Albion' se comportaram como resistentes ao nematoide. Foi possível relacionar a incidência de nematoide Meloidogyne hapla com a de "vermelhão" apenas na cultivar 'Camino Real'.

Biological control of the grapevine diseases ‘grey mold’ and ‘powdery mildew’ by Bacillus B27 and B29 strains.

Uncinula necator and Botrytis cinerea are the most destructive pathogens of the grapevine in Tunisia and elsewhere. We used two strains of Bacillus subtilis group, B27 and B29 to control powdery mildew and the grey mold disease of the grapevine. Green house experiments showed that B29 and B27 strains of the bacteria efficiently reduced the severity of powdery mildew up to 50% and 60%, respectively. Further, they decreased Botrytis cinerea development on grape leaf by 77% and 99%, respectively. The mode of action has been shown to be chitinolytic. These two bacteria showed significant production of total proteins discharged into the culture medium. Determination of some chitinolytic enzymes revealed the involvement of N-acetyl glucosaminidase (Nagase), the chitin-1,4-chitobiosidase (Biase) and endochitinase in degrading the mycelium of B. cinerea.

Antagonistic Effect of Streptomyces sp. BS062 against Botrytis Diseases

The use of microorganisms and their secreted molecules to prevent plant diseases is considered an attractive alternative and way to supplement synthetic fungicides for the management of plant diseases. Strain BS062 was selected based on its ability to inhibit the mycelial growth of Botrytis cinerea, a major causal fungus of postharvest root rot of ginseng and strawberry gray mold disease. Strain BS062 was found to be closely related to Streptomyces hygroscopicus (99% similarity) on the basis of 16S ribosomal DNA sequence analysis. Postharvest root rot of ginseng and strawberry gray mold disease caused by B. cinerea were controlled up to 73.9% and 58%, respectively, upon treatment with culture broth of Streptomyces sp. BS062. These results suggest that strain BS062 may be a potential agent for controlling ginseng postharvest root rot and strawberry gray mold disease.

Biological activity of a furanoeremophilane isolated from Senecio filaginoides var. filaginoides / Actividad biológica de un furanoeremofilano aislado de Senecio filaginoides var. filaginoides

Compound, 10H-9-oxofuranoeremophilane was isolated from Senecio filaginoides var. filaginoides, and its structure established on the basis of spectral analysis and and comparison with literature data. Antimicrobial activity was demonstrated against Candida spp but not against bacteria (Staphylococcus aureus, Escherichia coli and Pseudomona aeruginosa). Besides, the compound showed antifungal activity and effect on mycelial growth of the phytopathogenic fungus Botrytis cinerea. and comparison with literature data.

Un compuesto, 10H-9-oxofuranoeremofilano fue aislado de Senecio filaginoides var. filaginoides, esta estructura fue establecida sobre la base del análisis espectral y comparación con datos bibliográficos. La actividad antimicrobiana fue demostrada contra Candida spp pero no contra las bacterias (S.aureus, E.coli y P. aeruginosa). Además el compuesto mostró actividad antifúngica y efectos sobre el crecimiento micelial del hongo fitopatógeno Botrytis cinerea.

Avaliação do extrato etanólico de Ottonia martiana Miq. para o controle de duas doenças florestais / Evaluation of Ottonia martiana Miq. alcoholic extract to control two forest diseases

Metabólitos secundários presentes em plantas medicinais apresentam várias propriedades biológicas incluindo a atividade antifúngica. Esse estudo avaliou o potencial antifúngico da planta medicinal Ottonia martiana no controle da pinta-preta em erva-mate (Ilex paraguariensis) e do mofo-cinzento em eucalipto (Eucalyptus dunnii). Extrato etanólico (EBEtOH) dos órgãos totais (raízes, caules, folhas e frutos) foi preparado e testado na concentração de 1000 μg mL-1 contra os patógenos Cylindrocladium spathulatum (pinta-preta) e Botrytis cinerea (mofo-cinzento). Bioensaios in vitro (germinação de esporos e bioautografia direta) e in vivo (teste de patogenicidade em mudas) mostraram que o EBEtOH reduziu o crescimento micelial dos patógenos testados e a germinação dos esporos de C. spathulatum e estimulou a germinação de esporos de B. cinerea. O teste de patogenicidade mostrou que o controle da pinta-preta em erva-mate e do mofo cinzento em eucalipto não é viável usando-se a concentração testada de EBEtOH de O. martiana. Na bioautografia direta, foram detectadas zonas de inibição de crescimento micelial dos fungos e que foram relacionadas com a presença de piperovatina.

Secondary metabolites from medicinal plants have several biological properties, including antifungal activity. This study evaluated the antifungal potential of the medicinal plant Ottonia martiana to control maté leaf spot (Ilex paraguariensis) and eucalypt gray mould (Eucalyptus dunnii). Ethanol extract (EBEtOH) of the total parts (roots, stems, leaves and fruits) was prepared at the concentration of 1000 μg mL-1 and tested against Cylindrocladium spathulatum (maté leaf spot) and Botrytis cinerea (eucalypt gray mould). In vitro bioassays (spore germination and direct bioautography) and in vivo bioassays (pathogenicity test in seedlings) showed that EBEtOH reduced the mycelial growth of the tested pathogens and the germination of C. spathulatum spores and stimulated the germination of B. cinerea spores. The pathogenicity test showed that the control of maté leaf spot and eucalypt gray mould is not viable using the tested concentration of O. martiana EBEtOH. Zones of mycelial growth inhibition were detected in direct bioautography and were related to the presence of piperovatine.

Bioatividade de óleos essenciais no controle de Botrytis cinerea isolado de morangueiro / Essential oils bioactivity in strawberry grey mould control

Objetivou-se avaliar o uso de óleos essenciais sobre isolados de Botrytis cinerea, causador do mofo cinzento em morangueiro. Foram testados óleos essenciais de capim-limão, palmarosa, citronela, cravo, canela, menta, lavanda, tangerina, eucalipto, melaleuca, alecrim e laranja, todos estes analisados em cromatógrafo a gás acoplado a detector de massas, para identificação dos principais componentes dos óleos. Foram avaliados o crescimento micelial, produção e germinação de conídios de B. cinerea, com a incorporação do óleo no meio de cultura. Realizou-se ainda uma avaliação de voláteis e a eficiência de óleos em isolado resistente a fungicida. Para cada teste, diferentes óleos apresentaram eficiência, contudo capim limão, palmarosa, canela e menta demonstraram os melhores efeitos em todos os testes realizados. Todos os tratamentos a base de óleos demonstraram efeito semelhante a um fungicida recomendado para a cultura, a base de tiofanato metílico. Dois tratamentos mostraram-se efetivos no caso de isolado resistente (óleo de capim limão e de canela). Óleos essenciais mostram-se como opção promissora para o desenvolvimento de possíveis produtos fitossanitários para o manejo de doenças em plantas.

This study aimed evaluates essential oils in Botrytis cinerea isolates growth, which causes gray mould on strawberry. Were tested essential oils of lemon grass, palmrose, citronella, clove, cinnamon, mint, lavender, tangerine, eucalyptus, tea tree, rosemary and orange. The oils were analyzed in gas chromatograph attached to mass detector for identifying the mainly oils components. Were evaluated mycelial growth, conidia production and conidia germination of B. cinerea, with oil incorporation in culture medium. Were conducted an evaluation of oils volatile components and the efficiency of oils in fungicide-resistant isolate. For each test, different oils showed efficiency, however lemongrass, palmarosa, cinnamon and mint showed the best effects in all tests. All treatments demonstrated similar effects to recommended fungicide for the culture, which had methyl thiophanate. Two treatments (lemon grass and cinnamon oils), were effective against resistant isolate. Essential oils are shown as promising option for development of possible product for plant disease management.

First Report of Botrytis cinerea as a Postharvest Pathogen of Blueberry in Korea

Gray mold of blueberry caused by Botrytis sp. is reported for the first time in Korea. A detailed description of the fungus is given, along with its rDNA internal transcribed spacer sequence. The fungus was identified as Botrytis cinerea based on mycological characteristics and molecular data.

CONSTITUYENTES QUÍMICOS, ACTIVIDAD INSECTICIDA Y ANTIFÚNGICA DE LOS ACEITES ESENCIALES DE HOJAS DE DOS ESPECIES COLOMBIANAS DEL GÉNERO Ocotea (LAURACEAE) / CHEMICAL CONSTITUENTS, INSECTICIDE AND ANTIFUNGAL ACTIVITIES OF THE ESSENTIAL OILS OF LEAVES OF TWO COLOMBIAN SPECIES OF Ocotea GENUS (LAURACEAE) / CONSTITUENTS QUÍMICOS, ATMDADE ANTIFÚNGICA E INSETICIDA DE ÓLEOS ESSENCIAIS DE FOLHAS DE DUAS ESPECIES COLOMBIANO DO GÉNERO Ocotea (LAURACEAE)

En este estudio se determinó la composición química de los aceites esenciales de hojas de Ocotea longifolia y O. macrophylla obtenidos mediante destilación por arrastre convapor, yse evaluó la actividad antifúngica e insecticida de los aceites esenciales para estimar su uso como posibles plaguicidas. El rendimiento del aceite esencial de O. longifolia fue superior al 0,2%, mientras que el rendimiento del aceite esencial de O. macrophylla fue inferior al 0,1%. El análisis de los aceites por CG/EM permitió la identificación de α-terpinoleno (80,91%) y α-felandreno (4,74%) como componentes principales del aceite O. longifolia, y espatulenol (15,91%), γ-muuroleno (15,4%) y biciclogermacreno (14,58%) como los principales componentes de O. macrophylla. El aceite esencial de O. longifolia mostró actividad fumigante significativa contra Sitophilus zeamais (CL50 280,5 µL/L aire). Adicionalmente se evaluó la actividad antifúngica de los aceites esenciales, encontrándose un bajo efecto inhibidor en el crecimiento de los hongos fitopatógenos Fusarium oxysporum f. sp. dianthi y Botrytis cinerea.

This study determined the chemical composition of the essential oils isolated from leaves of Ocotea longifolia and O. macrophylla by steam distillation and the antifungal and insecticide activities of essential oils as potential pesticides were tested. The yield of essential oil of O. longifolia was more than 0.2%, while the essential oil yield of O. macrophylla was less than 0.1%. GC/MS analysis allowed the identification of α-terpinolene (80.91%) and α-phellandrene (4.74%) as the main constituents of O. longifolia oil, and spathulenol (15.91%), γ-muurolene (15.4%) and bicyclogermacrene (14.58%) as the major constituents of O. macrophylla. The essential oil of O. longifolia showed significant fumigant activity against Sitophilus zeamais (LC50 280.5 µL/L air), and could become an alternative to synthetic pesticides for controlling this pest. The antifungal activity of the essential oils also was evaluated. The essential oils showed low inhibitory effect on the growth of the phytopathogen fungi Fusarium oxysporum f. sp. dianthi and Botrytis cinerea.

Neste estudo nós determinamos a composicào química dos óleos essenciais das folhas de Ocotea longifolia e O. macrophylla obtidas por destilacáo a vapor e avaliaram a atividade antifúngica e inseticida de óleos essenciais para estimar a sua possível utilizacào como pesticidas. O rendimento do óleo essencial de O. longifolia foi superior a 0,2%, enquanto o rendimento doóleo essencial de O. acrophylla foi inferior a 0,1%. A análise dos óleos por CG/EM permitiu a identificacáo de α-terpinolene (80,91%) e α-felandreno (4,74%) como os principais componentes do óleo de O. longifolia, e espatulenol (15,91%), γ-muuroleno (15,4%) e biciclogermacreno (14,58%) como os principais componentes do óleo de O. macrophylla. O óleo essencial de O. longifolia mostraram atividade significativa contra Sitophilus zeamais (CL50 280,5 µL/L ar), e pode se tornar uma alternativa aos inseticidas sintéticos para o controle desta praga. A atividade antifúngica de óleos essenciais também foi avaliada. Os óleos essenciais de O. longifolia e O. macrophylla apresentaram baixo efeito inibitório sobre o crescimento dos fungos Fusarium oxysporum f. sp. dianthi e Botrytis cinerea.

Boty-II, a novel LTR retrotransposon in Botrytis cinerea B05.10 revealed by genomic sequence

Botrytis cinerea is a necrotrophic pathogen causing pre- and post-harvest diseases in at least 235 plant species. It manifests extraordinary genotype and phenotype variation. One of the causes of this variation is transposable elements. Two transposable elements have been discovered in this fungus, the retrotransposon (Boty), and the transposon (Flipper). In this work, two complete (Boty-II-76 and Boty-II-103) and two partial (Boty-II-95 and Boty-II-141) long terminal repeat (LTR) retrotransposons were identified by an in silico genomic sequence analysis. Boty-II-76 and Boty-II-103 contain 6439 bp nucleotides with a pair of LTRs at both ends, and an internal deduced pol gene encoding a polyprotein with reverse transcriptase and DDE integrase domains. They are flanked by 5 bp direct repeats (ACCAT, CTTTC). In Boty-II-141, two LTRs at both ends, and a partial internal pol gene encoding a protein with a DDE integrase domain were identified. In Boty-II-95, a right LTR and a partial internal pol gene encoding a protein with no conserved domains were identified. Boty-II uses a self-priming mechanism to initiate synthesis of reverse transcripts. The sequence of the presumed primer binding site for first-strand reverse transcription is 5’-TTGTACCAT-3’. The polypurine-rich sequence for plus-strand DNA synthesis is 5’-GCCTTGAGCGGGGGGTAC-3’. Fourteen Boty-II LTRs that contain 125-158 bp nucleotides and share 69.1 ~ 100 percent identities with the short inverted terminal repeats of 5 bp (TGTCA…TGACA) were discovered. Analysis of structural features and phylogeny revealed that Boty-II is a novel LTR retrotransposon. It could potentially be used as a novel molecular marker for the investigation of genetic variation in B. cinerea.

The Identification of Antagonistic Bacteria B-04 against Botrytis cinerea and Improving Biocontrol Effect through Genetic Modification with ?-1,3-glucanase Gene / 中国生物工程杂志

Bacillus cereus B-04 antagonist to Botrytis cinerea were isolated from samples of tomato soil infected by Botrytis cinerea in Zibo, which are identified through a series of morphological and biochemical characteristics and the sequence of 16SrDNA. Aiming at enhancing the inhibitory effect of this strain, a 4.1kb DNA fragment containing ?-1,3-glucanases gene from pUC1940 was inserted into vector pBE2 and pHY300PLK to construct recombination plasmids, PBE2-glu and pHY300PLK-glu, which were transferred into Bacillus cereus B-04, resulting in a new strain named B-04-glu. Restriction enzyme digestion and ?-1,3-glucanases plate culture confirmed that B-04-glu contained a functional ?-1,3-glucanases gene. Compared to the wild strain B-04, B-04-glu had an increased inhibitory effect against Botrytis cinerea on tomato.

Occurrence of Gray Mold Caused by Botrytis cinerea on Cryptotaenia japonica in Korea

A gray mold disease occurred on Cryptotaenia japonica in Korea. All the isolates of Botrytis sp. from the lesions of the diseased plants were identified to be B. cinerea based on the morphological characteristics. Conidia formed on conidiogenous cells were not in chains, hyaline to pale brown, unicellular, ellipsoidal to obovate with a single hilum at the base, entirely verruculose, and 6.3-11.3~6.3-10.0 microm in size. Pathogenicity of the fungus was proved by artificial inoculation on C. japonica. This is the first record of gray mold on C. japonica caused by B. cinerea in Korea.