Nematicidal activityin vitroandin vivoof neem oil onMeloidogyne incognita

Abstract

Considering the losses caused by nematodes in the different crops, chemical substances with nematicidal effect have been investigated and found in various plants. The neem oil is presented as an alternative to manage this pathogen. The aim of this study was to evaluate in vitro, the action of different doses of neem oil on the hatching and immobility of Meloidogyne incognita juveniles and in vivo in order to verify the data about the efficacy of neem oil to control nematodes of galls in tomato plants. In vitro assays were installed in laboratory conditions and in a completely randomized design with four replications. The experiment consisted of the following treatments: 1. Distilled water (100%); 2. Furadan (5%); 3. Neem oil (1%); 4. Neem oil (5%); 5. Neem oil (10%). For the experiment done in greenhouse, the experimental design was completely randomized with five replicates. The experiment consisted of the following treatments: 1. Control; 2. Neem oil in the soil; 3. Neem oil foliar; 4. Neem oil in the soil + leaf. The use of neem oil in vitro was effective only in the immobility of M. incognita at concentrations of 1%. The neem oil reduces the number of galls of M. incognita when in foliar application + soil at concentrations of 1%.Key words: Azadirachta indica A. Juss, immobility, nematode galls, hatching rate. Atividade nematicida in vitro e in vivo do óleo de nim sobre Meloidogyne incógnita ResumoConsiderando as perdas causadas por nematoides às diversas culturas, substâncias químicas com efeito nematicida têm sido pesquisadas e encontradas em várias plantas. O óleo de nim se apresenta como uma alternativa para manejar esse patógeno. O objetivo desta pesquisa foi avaliar in vitro a ação de diferentes doses do óleo de nim sobre a eclosão e imobilidade de juvenis de Meloidogyne incognita e in vivo com a finalidade de comprovar os dados relativos à eficácia do óleo de nim no controle de nematoides de galhas em plantas de tomate. Os ensaios in vitro foram instalados em condições de laboratório e em delineamento inteiramente casualizado com quatro repetições. O experimento constou dos seguintes tratamentos: 1. Água destilada (100%); 2. Furadan (5%); 3. Óleo de nim (1%); 4. Óleo de nim (5%); 5. Óleo de nim (10%). Para o experimento realizado em casa de vegetação, o delineamento experimental utilizado foi o inteiramente casualizado, com cinco repetições. O experimento constou dos seguintes tratamentos: 1. Testemunha; 2. Óleo de nim via solo; 3. Óleo de nim via foliar; 4. Óleo de nim via solo + foliar. A utilização do óleo de nim in vitro foi efetivo apenas na imobilidade de M. incognita nas concentrações de 1%. O óleo de nim reduz o número de galhas de M. incognita quando aplicado via foliar + solo nas concentrações de 1%. Palavras-chave:Azadirachta indica A. Juss, imobilidade, nematoides das galhas, taxa de eclosão. Actividad nematicida in vitro e in vivo de Aceite de Neem sobre Meloidogyne incognita ResumenTeniendo en cuenta las pérdidas causadas por nematodos en diferentes cultivos, distintas sustancias...

Nematicidal effectivity of neem oil, castor oil, and pyrethroids toward foliar nematode (Aphelenchoides fragariae) mortality

“…From leaf-disc assays of neem oil on A. fragariae by An et al, demonstrated that neem oil caused 36.22% and 91.08% mortality in a 20 and 2-fold dilution (in 4.76% and 33.33% concentration, respectively) within 24 -72 hours of exposure time [15]. In a similar in vitro test on M. incognita J2, the use of neem oil in vitro was effective only in the immobility of M. incognita at concentrations of 1% in the control of active J2, with a percentage of 11% immobility that was different statistically from the control with 84.8% and smaller than the other treatments [8]. Neem oil is a type of vegetable oil that is made from the neem (Azadirachta indica) seed kernels.…”

“…Most of the available investigations on neem oil, castor oil, and pyrethroids against nematodes were mostly targeted at root-knot nematodes Meloidogyne spp. [8,9,10] and a few studies on A. fragariae.…”