RESUMO. Nematoides formadores de galhas (Meloidogyne sp.) são responsáveis pela baixa produtividade na cultura do feijoeiro, cujas perdas, provocadas por esses patógenos, podem chegar até 90%. O presente estudo teve como objetivo avaliar o comportamento de seis linhagens de feijoeiro ('Hav 06', 'Hav 11', 'Hav 28', 'Hav 50', 'Hav 69' e 'Torino') frente ao parasitismo de M. javanica e de M. paranaensis. As linhagens foram inoculadas com 5.000 ovos e eventuais juvenis dos respectivos nematoides. O delineamento experimental foi inteiramente casualizado, com dez repetições para cada tratamento com os nematoides e dez repetições para testemunha sem inoculação. Quarenta e cinco dias após inoculação, os sistemas radiculares foram coletados, lavados e avaliados quanto à produção de ovos e estimativa do Fator de Reprodução (FR). Os resultados mostraram baixa reprodução dos nematoides nas linhagens de feijão-vagem avaliadas, e que, para M. javanica, o FR variou de 0,02 a 0,05, enquanto que, para M. paranaensis, a variação foi de 0,04 a 0,36, indicando que todas as linhagens se comportaram como resistentes, apresentando FR < 1.Palavras-chave: nematoide-de-galha, resistência, feijoeiro. ABSTRACT. Reaction of snap bean to Meloidogyne javanica and M. paranaensis in greenhouse.Root-knot nematodes (Meloidogyne sp.) are responsable for low productivity on bean culture, where the losses caused by this pathogen can reach 90%. The present study aimed to evaluate the behavior of six bean lineages ('Hav 06', 'Hav 11', 'Hav 28', 'Hav 50', 'Hav 69' and 'Torino') against the parasitism of M. javanica and M. paranaensis. The lineages were inoculated with 5,000 eggs and possible juveniles of each nematode in a completely randomized design, with 10 replications per treatment with the nematodes and 10 replications per treatment without inoculation (control). Forty-five days after inoculation, the roots systems were collected, washed and evaluated for egg production and estimated reproduction factor (RF). The results showed that, for M. javanica, the RF varied from 0.02 to 0.05, while for M. incognita the variation was from 0.04 to 0.36, showing that all snap bean genotypes were resistant, presenting a RF < 1.
RESUMOCom a finalidade de diminuir as perdas causadas pelos nematóides do gênero Meloidogyne (Goeldi, 1887) na cultura do cafeeiro, dentre as diversas medidas de manejo, o controle biológico com o fungo Paecilomyces lilacinus (Thom., 1910) ABSTRACTIn order to reduce the losses caused by nematodes of the genus Meloidogyne (Goeldi, 1887) in coffee plantation, among several management measures, biological control with the fungus Paecilomyces lilacinus (Thom., 1910) Samson, 1974 stands out as an advantageous alternative of control, from the ecological or economy points of view. Thus, the objective of this work was to evaluate ten isolates of Paecilomyces lilacinus in the control of Meloidogyne paranaensis in coffee trees (Coffea arabica L.) cv. Icatú, in greenhouse conditions. In the first experiment, the coffee seedlings were transplanted to substrate where tomato plants were previously cultivated, for M. paranaensis multiplication. The soil was mixed with 50 g rice colonized with ten isolates of P. lilacinus. In the second experiment, coffee seedlings were transplanted to substrate (1 sand: 1 dirt) with 50 g rice colonized with the isolates of P. lilacinus. Then, the seedlings were inoculated with suspension of ±5000 eggs of M. paranaensis. In the two experiments, a new application was made with 50 g of the isolates after fifteen days. The design was completely randomized with twelve treatments and ten replicates. After 90 they days were evaluated. The isolated of P. lilacinus did not affect the diameter of the coffee stalk. In the first experiment, the isolates Pae 22, 24, and 28 promoted the growth of the seedlings, all of the isolates reduced the population of eggs in the root system, and the isolates Pae 3 and 12 reduced the population of J2 of M. paranaensis in the soil. In the second experiment, the isolates Pae 3, 10, 12, and 13 favored the growth of the plants but reduced the weight of the fresh roots, all of the isolates reduced the population of J2 in the soil, and the isolates Pae 3, 10, 13, 18, 22, and 24 reduced the malformations caused by M. paranaensis roots.
RESUMO. O uso de híbridos e genótipos de milho resistentes aos nematóides formadores de galhas em sistemas de rotação de culturas mantém sua população em níveis baixos, diminuindo as perdas e possibilitando, posteriormente, o uso de genótipos mais suscetíveis. No presente trabalho, foi avaliada a resistência de 18 genótipos de milho ao parasitismo de M. paranaensis e a M. incognita raça 1 em casa-de-vegetação. As plantas foram inoculadas com 5.000 ovos e eventuais juvenis dos respectivos nematóides. O delineamento utilizado foi inteiramente ao acaso, com dez repetições para cada tratamento com os nematóides e cinco repetições para a testemunha sem inoculação. Também foi realizada a técnica de coloração das raízes com fucsina ácida, pelo método de Byrd et al. (1972). Sessenta dias após a inoculação, os sistemas radiculares foram coletados, lavados e avaliados quanto à penetração, produção de ovos e estimativa do Fator de Reprodução (FR). Os resultados mostraram que, para M. paranaensis, o FR variou de 0,01 a 0,08; para M. incognita, a variação foi de 0,01 a 0,03, mostrando que todos os genótipos se comportaram como resistentes, apresentando FR < 1. Palavras-chave:Zea mayz, nematóide, resistência, genótipo. ABSTRACT. Reaction of corn genotypes to parasitism fromMeloidogyne incognita breed 1 and M. paranaensis. The use of corn hybrids and genotypes resistant to root-knot nematodes in crop rotation systems reduce the population of nematodes, preventing losses and allowing for the use of more susceptible genotypes. In this study, the resistance of eighteen hybrids of corn to parasitism of Meloidogyne paranaensis and M. incognita breed 1 were evaluated in a greenhouse. The plants were inoculated with 5,000 eggs and possible juveniles of each nematode in a completely randomized design, using ten replicates for each treatment with nematodes, and five replicates for the treatment without inoculation (control). The root staining technique using acid fuchsin was also applied, according to Byrd et al. (1972). Sixty days after the inoculation, the roots systems were collected, washed and evaluated for penetration, egg production and estimated reproduction factor (RF). The results showed that, for M. paranaensis, the RF varied from 0.01 to 0.08, while for M. incognita the variation was from 0.01 to 0.03, showing that all corn genotypes were resistant, presenting a RF < 1.
Tagetes minuta is a plant presenting pest and disease control potential, although its activity on some plant parasite nematode species is poorly investigated. The aim of the current study is to evaluate the best T. minuta propagation way, as well as the plant reaction to nematodes such as Heterodera glycines, Meloidogyne incognita and Pratylenchus brachyurus, through nematode penetration and reproduction studies and root morphological assessments. Seedlings obtained from woody cuttings showed larger rooting and stem diameter. Heterodera glycines penetration was higher than that recorded for M. incognita. However, both species recorded reproduction factor (RF) lower than one, as well as maximum RF values 0.34 and 0.02 for H. glycines and M. incognita, respectively. The highest FR recorded for T. minuta were found in P. brachyurus (0.96 and 0.80) in the 60th and 80th day after inoculation (DAI). Root anatomy changes were observed in the 80th DAI in plants inoculated with P. brachyurus. Tagetes minuta was resistant to all nematodes; however, it did not prevent P. brachyurus activity in its roots.
The genus Tagetes constitutes a group of antagonistic plant species that are cytotoxic against plant pathogenic nematodes, with T. patula being particularly efficient. The aim of this study was to evaluate the in vitro effect of extracts and semi-purified fractions of T. patula flowers on eggs and second-stage juveniles (J 2 ) of Meloidogyne incognita, M. javanica, and M. paranaensis, as well as to verify the nematicidal effect of the flavonoids present in T. patula flowers. Extracts and semi-purified fractions were obtained from dried T. patula flowers after maceration and liquidification, yielding crude aqueous (CAE) and crude ethanol-water (CEWE) extracts. Dried flowers were also treated with n-hexane to obtain a crude defatted aqueous extract (CDAE) and a crude ethanol-water defatted extract (CEWDE). Then, the CEWE was fractionated, and the ethyl acetate (EAF), ethanol (EF), methanol (MF), and ethanol:water (EWF) fractions were obtained. CAE, CEWE, CDAE, and CEWDE were tested to evaluate their effects on hatching, mobility, and mortality of J 2 of M. incognita, M. javanica, and M. paranaensis. EAF, EF, MF, and EWF fractions were tested on the same variables of M. incognita. All extracts significantly reduced J 2 hatching of M. incognita, M. javanica, and M. paranaensis when compared to water and water + DMSO. CEWE had nematicidal effects on the three evaluated species, whereas CEWDE demonstrated nematicidal effects against M. incognita and M. javanica, and nematostatic effects on M. paranaensis. This toxic effect showed by CEWE may be related to the high content of quercetin, a major substance present in this sample. It was also observed that EAF accentuated the nematicidal response on Meloidogyne spp., suggesting that other medium polarity (methoxylated) flavonoids act as nematotoxic substances. Thus, these results suggest that quercetin contributes significantly to the nematicidal activity of CEWE and EAF.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2025 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.