Eficácia de extratos de nim para o controle do oídio do feijoeiro

Carneiro, Solange Monteiro de Toledo Piza Gomes; Pignoni, Ericka; Vasconcellos, Maria Elizabeth da Costa; Gomes, José Carlos

doi:10.1590/s0100-54052007000100005

Cited by 20 publications

(18 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Abbasi et al (2004) reported the absence of neem oil toxicity to tomato plants. For other crops, neem toxicity has been variable (Xuan et al 2004, Carneiro et al 2007, Pinheiro et al 2009.…”

Section: Discussionmentioning

confidence: 99%

Alternative control of Tetranychus evansi Baker & Pritchard (Acari: Tetranychidae) on tomato plants grown in greenhouses

Soto¹,

Venzon²,

Oliveira³

et al. 2010

Neotrop. entomol.

View full text Add to dashboard Cite

-Tetranychus evansi Baker & Pritchard is an important pest of solanaceous plants, including tomatoes. This mite is characterized by a high reproductive rate, which leads to high population growth in a short period of time causing important economic damage. Control of T. evansi is mainly through synthetic acaricides. In searching for environmentally friendly control measures, we evaluated the effi ciency of alternative products to control T. evansi on tomato plants under greenhouse conditions. The products tested were lime sulphur and neem based products. We fi rst estimated the lethal concentration (LC) and instantaneous rate of increase (r i ) of T. evansi exposed to different product concentrations in laboratory conditions, and later tested the effi cacy of LC 95 and the concentrations that restrained mite population growth (r i = 0) in greenhouse conditions. The following treatments were repeated three times: NeemPro (81.0 and 71.6 mg a.i./l), Natuneem (31.1 and 20.4 mg ai/l), Organic Neem (39.1 and 30.4 mg a.i./l), lime sulphur (1.0 and 0.6%) and water (control). For all products, control provided by LC 95 was higher than provided for lower concentrations (r i = 0) one day after spraying. However, after fi ve days, for both concentrations, the percentage of T. evansi population reduction was superior to 95% and increased over time. Only plants sprayed with Natuneem (31.1 mg a.i./l) showed symptoms of phytotoxicity. Lime sulphur and neem based products, applied in appropriate concentrations and formulations, bear out as a viable alternative to control T. evansi on tomato plants.KEY WORDS: Acari, Azadirachta indica, lime sulphur, effi ciency, phytotoxicityThe tomato red spider mite, Tetranychus evansi Baker & Pritchard, is an important pest of solanaceous plants, especially tomatoes (Flechtmann 1983, Bonato 1999, Ferragut & Escudero 2002. This mite is characterized by a high reproductive capacity, which leads to high population levels in a short time, causing important economic damage (Moraes & McMurtry 1986). Additionally, the mite produces large quantities of webs on the infested plants, hampering the action of natural enemies (Gerson 1985, Sabelis & Bakker 1992. The control of T. evansi in tomato is done mainly with application of synthetic pesticides. Despite its relative effi ciency, chemical control has several negative impacts as the selection of resistant individuals due to the continuous use of certain active ingredients, the reduction or elimination of benefi cial species, the high toxicity of products to applicators, and the presence of residues in food (Picanço et al 2007, Maniania et al 2008.A viable alternative to the problems arising from excessive use of synthetic pesticides in tomato production is the use of methods that provide control with social and environmental safety. In the search for such methods, natural enemies are being evaluated as biological control agents of T. evansi (Wekesa et al 2005, Furtado et al 2007, Brito et al 2009. Another strategy that has been used where con...

show abstract

Section: Discussionmentioning

confidence: 99%

Alternative control of Tetranychus evansi Baker & Pritchard (Acari: Tetranychidae) on tomato plants grown in greenhouses

Soto¹,

Venzon²,

Oliveira³

et al. 2010

Neotrop. entomol.

View full text Add to dashboard Cite

show abstract

“…El AUDPC para la incidencia fue menor para la aplicación 24 horas después de la inoculación de patógenos a la mayor concentración. El of the applicator have been the subject of various studies, such as those conducted by Bettiol et al (1999), Carneiro et al (2007) and Faria et al (2011), among others. These alternative control methods are normally based on obtaining the extract of a specific plant or product that shows capacity for inhibiting infection.…”

Section: Debido a Sus Propiedades Antimicrobianas El Propóleo Ha Sidomentioning

confidence: 99%

Propolis for the control of powdery mildew and the induction of phytoalexins in cucumber

Guginski-Piva

Santos

Júnior³

et al. 2015

Idesia

View full text Add to dashboard Cite

Due to its antimicrobial properties propolis has been utilised by man for millennia, however, only recently has its use as an agricultural antimicrobial agent been tested. The capacity of this product to activate plant defence mechanisms is highly promising, due to the large number of substances in its composition. Therefore, the objective of this study was to evaluate the effect of different concentrations and application times of ethanol extracts of propolis (EEP) on powdery mildew (Podosphaera fuliginea) in cucumber crops, to establish the most suitable method for control and whether or not there is potential to induce plant defence mechanisms. The experiment was conducted in pots in a greenhouse. A completely randomised experimental design was employed, using a 6x3 factorial consisting of six concentrations (0; 0.5; 1; 2; 4 and 8%) and three EEP application times (24 hours before pathogen inoculation, 24 hours after pathogen inoculation and at the onset of first symptoms of the disease), replicated four times. Evaluations for disease incidence and severity were made weekly. The experiment was repeated for a second crop, following the same methodology established in the first. We also evaluated the effect of different EEP concentrations on the activation of plant defence mechanisms, through the induction of phytoalexins in soybean (Glycine max) cotyledons. A significant interaction was observed between the factors (application time x concentration) for disease incidence. For the area under the disease progress curve (AUDPC) for severity there was no interaction observed between the factors, however, we observed significant differences for the two factors separately. The AUDPC for incidence was less for the application 24 hours after pathogen inoculation, principally at the highest concentration. The 8% concentration of EEP controlled disease severity by 31.33 and 43.68% for the first and second crops, respectively. The application of the concentrations 24 hours before and 24 hours after pathogen inoculation showed less AUDPC for severity, but this difference was not significant for either crop. The EEP induced increasing phytoalexin levels in soybean cotyledons as the applied EEP concentration increased. Ethanol extracts of propolis could have potential for the control of powdery mildew, principally in cucumbers, through the preventive application of an 8% concentration.

show abstract

“…Dentre as alternativas de manejo, encontram-se os óleos essenciais de algumas espécies vegetais os quais são eficazes no controle de doenças de plantas, seja por uma ação fungitóxica direta ou por um aumento no nível de resistência, que envolve a síntese de fitoalexinas, enzimas como a peroxidase e polifenoloxidase, e compostos fenólicos, substâncias participantes do mecanismo de defesa de plantas (Rezende et al, 2002;Carneiro, 2007;Anaruma et al, 2010;Leite et al, 2011;Nozaki et al, 2013).…”

Section: Palavras-chaveunclassified

“…Os óleos extraídos das plantas possuem um custo menor que os fungicidas, são facilmente acessíveis ao agricultor, e oferecem baixo risco à saúde humana e ao ambiente (Martinez, 2002;Carneiro, 2007). No entanto, uma grande parcela de plantas brasileiras ainda não foram pesquisadas e entre as estudadas, pouco se sabe da ação de seus compostos secundários sobre fitopatógenos (Aquino, 2012).…”

Section: Palavras-chaveunclassified

ÓLEOS ESSENCIAIS COMO ALTERNATIVA PARA O CONTROLE DO Colletotrichum coffeanum NO CAFEEIRO

et al. 2016

View full text Add to dashboard Cite

Na cultura do café o gênero Colletotrichum, causador de doenças conhecidas como antracnose, acarreta perdas significativas em sua produção. Este estudo avaliou o efeito de óleos essenciais sobre a germinação de conídios e o crescimento micelial de Colletotrichum coffeanum e na redução da severidade da antracnose em folhas de café. Folhas destacadas de café foram tratadas com óleos essenciais de citronela, capim-limão e hortelã nas concentrações de 0; 5; 7,5; 10 e 15 µLmL -1 e após 24h avaliadas quanto a fitotoxidez para proceder com a inoculação. A germinação de conídios foi conduzida com a deposição de 100 µL de cada tratamento sobre 100 µL da suspensão de conídios (10 4 conídios mL -1 ). Para o crescimento micelial, os óleos essenciais foram incorporados ao meio BDA e a mistura vertida em placas de Petri. Após solidificação, um disco de micélio foi repicado no centro da placa. A maior concentração dos óleos causaram fitotoxidez nas folhas, sendo que todas as concentrações do capimlimão foram fitotóxicos 24h após os tratamentos. Hortelã e citronela nas concentrações 5; 7,5 e 10 µLmL -1 não apresentaram fitotoxidez ou apresentaram fitotoxidez reduzida. Até 15 dias após a inoculação não foram observados sintomas da antracnose nas folhas. Hortelã e a citronela, nas três concentrações utilizadas, reduziram significativamente a germinação de conídios e o crescimento micelial. Dessa forma, acredita-se que as concentrações utilizadas contribuíram para fitotoxidez observada. Entretanto, este estudo serve como ponto de partida para que outros sejam conduzidos com estes óleos, utilizando concentrações menores e também com testes envolvendo plantas. Palavras-chave:Controle alternativo, eliciador, fitotoxidez, fungistático.Essential oils as alternative for the control of Colletotrichum coffeanum at the coffee tree. In the coffee culture the Colletotrichum genus which cause diseases known as anthracnose, causes significant lost in coffee production. The study evaluated the effect of essential oils on the conidial germination and mycelium growth of the Colletotrichum coffeanum and in the reduction of severity of anthracnose in coffee leaves. Coffee detached leaves were collected and treated with citronella, lemongrass and mint essential oils at concentrations 0; 5; 7,5; 10 and 15 µLmL -1 , and after 24h were evaluated for phytotoxicity to proceed with the inoculation. Conidial germination was conducted with the deposition of 100 µL of each treatment on 100 µL of the conidial suspension (10 4 conidial mL -1 ). For mycelium growth essential oils were added to BDA media and the mixture poured into Petri dishes. After solidification, a mycelial disc was peaked to the center of the plate. The highest concentration of oils caused phytotoxicity in the leaves, and all lemongrass concentrations were phytotoxic 24 hours after the treatments. Mint and citronella in concentrations 5; 7.5 and 10 µLmL -1 showed no phytotoxicity or had reduced phytotoxicity. Symptoms of anthracnose were not observed 15 days after inoculation on the leaves....

show abstract

Eficácia de extratos de nim para o controle do oídio do feijoeiro

Cited by 20 publications

References 9 publications

Alternative control of Tetranychus evansi Baker & Pritchard (Acari: Tetranychidae) on tomato plants grown in greenhouses

Alternative control of Tetranychus evansi Baker & Pritchard (Acari: Tetranychidae) on tomato plants grown in greenhouses

Propolis for the control of powdery mildew and the induction of phytoalexins in cucumber

ÓLEOS ESSENCIAIS COMO ALTERNATIVA PARA O CONTROLE DO Colletotrichum coffeanum NO CAFEEIRO

Contact Info

Product

Resources

About