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Molecular Comparison of Iranian Populations of Meloidogyne javanica and Meloidogyne incognita with PCR-RFLP  

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Full Text Available To carry out this study, total DNA was extracted from eggs and from second stage juveniles of several populations of Meloidogyne javanica and Meloidogyne incognita, using phenol / chloroform method. Following extraction, DNA was electrophoresed on 1% agarose gel to determine its quality and quantity. A specific primer pair (C2F3 / 1108; 23 and 20 nucleotides, respectively was used to discriminate M. javanica from M. incognita populations using polymerase chain reaction (PCR. Primer annealing sites were located in the 3? portion of mitochondrial gene encoding cytochrome oxidase subunit II (COII and in the 16S rRNA gene. Following PCR amplification, electrophoresis of amplified DNA showed 1.7 kb fragment in populations of both species. Digestion of 1.7 kb amplified product with HinfI restriction endonuclease resulted in the generation of two DNA fragments of 0.7 and 1.0 kb in M. javanica and three DNA fragments of 0.3, 0.4 and 1.0 kb in M. incognita. There were no differences in the digestion patterns among various populations of each species examined.

M. Mohammadi

2007-01-01

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Influence of Initial Population Densities of Meloidogyne incognita on Three Chile Cultivars  

OpenAIRE

The effects of Meloidogyne incognita on the Big Jim, Jalapeno, and New Mexico No. 6 chile (Capsicum annuum) cultivars were investigated in microplots for two growing seasons. All three cultivars were susceptible to M. incognita and reacted similarly to different initial populations of this nematode. Severe stunting and yield suppressions occurred at all initial M. incognita densities tested ranging from 385 to 4,230 eggs and larvae/500 cm³ soil. Regression analysis of the microplot data from...

Lindsey, D. L.; Clayshulte, Margaret Stefano

1982-01-01

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Influence of Initial Population Densities of Meloidogyne incognita on Three Chile Cultivars.  

Science.gov (United States)

The effects of Meloidogyne incognita on the Big Jim, Jalapeno, and New Mexico No. 6 chile (Capsicum annuum) cultivars were investigated in microplots for two growing seasons. All three cultivars were susceptible to M. incognita and reacted similarly to different initial populations of this nematode. Severe stunting and yield suppressions occurred at all initial M. incognita densities tested ranging from 385 to 4,230 eggs and larvae/500 cm(3) soil. Regression analysis of the microplot data from a sandy loam soil showed yield losses of 31% for the 1978 season and 25% for the 1979 season for the three cultivars for each 10-fold increase in the initial population of M. incognita. PMID:19295720

Lindsey, D L; Clayshulte, M S

1982-07-01

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Effect of a Terminated Cover Crop and Aldicarb on Cotton Yield and Meloidogyne incognita Population Density  

OpenAIRE

Terminated small grain cover crops are valuable in light textured soils to reduce wind and rain erosion and for protection of young cotton seedlings. A three-year study was conducted to determine the impact of terminated small grain winter cover crops, which are hosts for Meloidogyne incognita, on cotton yield, root galling and nematode midseason population density. The small plot test consisted of the cover treatment as the main plots (winter fallow, oats, rye and wheat) and rate of aldicarb...

Wheeler, T. A.; Leser, J. F.; Keeling, J. W.; Mullinix, B.

2008-01-01

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Effect of a Terminated Cover Crop and Aldicarb on Cotton Yield and Meloidogyne incognita Population Density.  

Science.gov (United States)

Terminated small grain cover crops are valuable in light textured soils to reduce wind and rain erosion and for protection of young cotton seedlings. A three-year study was conducted to determine the impact of terminated small grain winter cover crops, which are hosts for Meloidogyne incognita, on cotton yield, root galling and nematode midseason population density. The small plot test consisted of the cover treatment as the main plots (winter fallow, oats, rye and wheat) and rate of aldicarb applied in-furrow at-plant (0, 0.59 and 0.84 kg a.i./ha) as subplots in a split-plot design with eight replications, arranged in a randomized complete block design. Roots of 10 cotton plants per plot were examined at approximately 35 days after planting. Root galling was affected by aldicarb rate (9.1, 3.8 and 3.4 galls/root system for 0, 0.59 and 0.84 kg aldicarb/ha), but not by cover crop. Soil samples were collected in mid-July and assayed for nematodes. The winter fallow plots had a lower density of M. incognita second-stage juveniles (J2) (transformed to Log(10) (J2 + 1)/500 cm(3) soil) than any of the cover crops (0.88, 1.58, 1.67 and 1.75 Log(10)(J2 + 1)/500 cm(3) soil for winter fallow, oats, rye and wheat, respectively). There were also fewer M. incognita eggs at midseason in the winter fallow (3,512, 7,953, 8,262 and 11,392 eggs/500 cm(3) soil for winter fallow, oats, rye and wheat, respectively). Yield (kg lint per ha) was increased by application of aldicarb (1,544, 1,710 and 1,697 for 0, 0.59 and 0.84 kg aldicarb/ha), but not by any cover crop treatments. These results were consistent over three years. The soil temperature at 15 cm depth, from when soils reached 18 degrees C to termination of the grass cover crop, averaged 9,588, 7,274 and 1,639 centigrade hours (with a minimum threshold of 10 degrees C), in 2005, 2006 and 2007, respectively. Under these conditions, potential reproduction of M. incognita on the cover crop did not result in a yield penalty. PMID:19259531

Wheeler, T A; Leser, J F; Keeling, J W; Mullinix, B

2008-06-01

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Preferred Temperature of Meloidogyne incognita  

OpenAIRE

In laboratory thermal gradients, newly hatched infective juveniles of the plant-parasitic root-knot nematode Meloidogyne incognita migrated toward a preferred temperature that was several degrees above the temperature to which they were acclimated. After shifting egg masses to a new temperature, the preferred temperature was reset in less than a day. Possible functions of this type of thermotaxis are discussed, including the use of thermal gradients around plant roots to locate hosts and to m...

Diez, James A.; Dusenbery, David B.

1989-01-01

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Interactions Between Meloidogyne incognita and Pratylenchus brachyurus on Soybean  

OpenAIRE

Interactions among Meloidogyne incognita, Pratylenchus brachyurus, and soybean genotype on plant growth and nematode reproduction were studied in a greenhouse. Coker 317 (susceptible to both nematodes) and Gordon (resistant to M. incognita, susceptible to P. brachyurus) were inoculated with increasing initial population densities (Pi) of both nematodes individually and combined. M. incognita and P. brachyurus individually usually suppressed shoot growth of both cultivars, but only root growth...

Herman, M.; Hussey, R. S.; Boerma, H. R.

1988-01-01

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Predicting Damage of Meloidogyne incognita on Watermelon  

Science.gov (United States)

Quantitative growth response of watermelon (Citrullus lanatus) sensitive to Meloidogyne incognita is poorly understood. Determination of soil population densities of second-stage juveniles (J2) of M. incognita with Baermann funnel extraction often is inaccurate at low soil temperatures. In greenhouse experiments, three sandy soils were inoculated with dilution series of population densities of eggs or J2 of M. incognita and planted in small containers to watermelon ‘Royal Sweet’ or subjected to Baermann funnel extraction. After five weeks of incubation in the greenhouse bioassay plants in egg-inoculated soils, gall numbers on watermelon roots related more closely to inoculated population densities than J2 counts after Baermann funnel extraction. In April 2004, perpendicularly-inserted tubes (45-cm diameter, 55-cm deep) served as microplots where two methyl bromide-fumigated sandy soils were inoculated with egg suspensions of M. incognita at 0, 100, 1,000 or 10,000 eggs/100 cm3 of soil in 15-cm depth. At transplanting of 4-week old watermelon seedlings, soils were sampled for the bioassay or for extraction of J2 by Baermann funnel. In the Seinhorst function of harvested biomass in relation to nematode numbers, decline of biomass with increasing population densities of M. incognita was accurately modeled by the inoculated eggs (R2 = 0.93) and by the counts of galls on the bioassay roots (R2 = 0.98); but poorly by J2 counts (R2 = 0.68). Threshold levels of watermelon top dry weight to M. incognita were 122 eggs/100 cm3 soil, 1.6 galls on bioassay roots, or 3.6 J2/100 cm3 of soil. Using the bioassay in early spring for predicting risk of nematode damage appeared useful in integrated pest management systems of watermelon. PMID:23482631

Xing, Lijuan; Westphal, Andreas

2012-01-01

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Responses of Cotton Yield and Meloidogyne incognita Soil Populations to Soil Applications of Aldicarb and 1,3-D in Florida  

OpenAIRE

In four tests conducted in loamy-sand soils in northern Florida, cotton lint yield increased and post-harvest soil populations of Meloidogyne incognita were more effectively suppressed by 1,3-dichloropropene (1,3-D) than aldicarb when both nematicides were evaluated over a range of recommended rates. Significant positive relationships existed between lint yield and rates of 1,3-D in three tests, whereas only one significant positive relationship occurred between lint yield and aldicarb rates....

Kinloch, R. A.; Rich, J. R.

1998-01-01

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Influence of 1,3-Dichloropropene, Fenamiphos, and Carbofuran on Meloidogyne incognita Populations and Yield of Chile Peppers  

OpenAIRE

Field trials were conducted during 1986, 1988, 1989, and 1991 to compare the effects of 1,3-dichloropropene, fenamiphos, and carbofuran on yield and quality of chile peppers (Capsicum annuum) in soil infested with Meloidogyne incognita. When compared with untreated plots, numbers of M. incognita juveniles recovered from soil 60 and(or) 90 days after chile pepper emergence were reduced (P = 0.05) following 1,3-D treatment every year except 1986. Nematode numbers were also reduced (P = 0.05) by...

Thomas, S. H.

1994-01-01

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Biomass Partitioning in Tomato Plants Infected with Meloidogyne incognita  

OpenAIRE

Tomato plants were inoculated with Meloidogyne incognita at initial populations (Pi) of 0, 1, 10, 50, 100, and 200 (x 1,000) eggs per plant and maintained in a growth chamber for 40 days. Total fresh biomass (roots + shoots) at harvest was unchanged by nematode inoculation with Pi of 1 x 10? eggs or less. Reductions in fresh shoot weight with increasing Pi coincided with increases in root weight. Total fresh biomass declined with Pi above 1 x 10? eggs, whereas total dry biomass declined a...

Fortnum, B. A.; Kasperbauer, M. J.; Hunt, P. G.; Bridges, W. C.

1991-01-01

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Influence of 1,3-Dichloropropene, Fenamiphos, and Carbofuran on Meloidogyne incognita Populations and Yield of Chile Peppers.  

Science.gov (United States)

Field trials were conducted during 1986, 1988, 1989, and 1991 to compare the effects of 1,3-dichloropropene, fenamiphos, and carbofuran on yield and quality of chile peppers (Capsicum annuum) in soil infested with Meloidogyne incognita. When compared with untreated plots, numbers of M. incognita juveniles recovered from soil 60 and(or) 90 days after chile pepper emergence were reduced (P = 0.05) following 1,3-D treatment every year except 1986. Nematode numbers were also reduced (P = 0.05) by fenamiphos in 1989. Chile pepper yields were significantly higher than those in untreated control plots (P = 0.05) all 4 years in plots treated with 1,3-D and in 1989 in plots treated with fenamiphos. Use of carbofuran did not significantly reduce nematode numbers or enhance yields in these experiments. Green chile pepper fruit quality was enhanced (P = 0.05) following 1,3-D treatments in 1988 and 1989 but was unaffected by fenamiphos or carbofuran application. Increasing placement depth of 1,3-D from 28 to 48 cm increased (P = 0.05) red chile pepper yield compared with that obtained with conventional placement in 1988 only, and did not affect green chile pepper yield. PMID:19279948

Thomas, S H

1994-12-01

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Reproduction of Four Races of Meloidogyne incognita on Hibiscus cannabinus  

OpenAIRE

The feasibility of cultivation of kenaf (Hibiscus cannabinus) in the United States is receiving a multifaceted evaluation. Among the factors being evaluated is kenafs susceptibility to nematodes. In this investigation, four races of Meloidogyne incognita reproduced extensively on each of the several kenaf genotypes examined in greenhouse tests. Some genotypes of kenaf, however, demonstrated limited resistance to certain races of M. incognita.

Veech, Joseph A.

1992-01-01

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Effects of Soil Type on the Damage Potential of Meloidogyne incognita on Soybean  

OpenAIRE

Effects of soil type on the reproduction and damage potential of Meloidogyne incognita on soybean, Glycine max (L.) Merr., were determined at five locations in North Carolina, including one site where plots with six soil types were established. M. incognita reproduced readily on a susceptible soybean cultivar in most soil types, with somewhat limited reproduction in muck soils. The relationship between initial population densities and yield varied among soil types and nematode populations. Yi...

Windham, G. L.; Barker, K. R.

1986-01-01

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Elementos del ciclo de vida de población cubana de Meloidogyne incognita (Kofoid y White) Chitwood en Solanum lycopersicum L. / Life cycle elements of a Cuban population Meloidogyne incognita (Kofoid and White) in Solanum lycopersicum L.  

Scientific Electronic Library Online (English)

Full Text Available El experimento se desarrolló en condiciones semicontroladas, en aisladores biológicos (18-21ºC), con el objetivo de determinar la duración del ciclo de vida de Meloidogyne incognita (Kofoid y White) Chitwood y la producción de huevos por hembras adultas en las primeras 96h en tomate (Solanum lycoper [...] sicum L.). Plantas de unos 15cm de altura se trasplantaron a macetas y una semana después se inocularon 2500±5 J2 de M. incognita raza 2. A las 72 horas se retiraron y plantaron en macetas con suelo estéril. El sistema radical fue extraído seis días post-inoculación para observar los diferentes estadios. La temperatura media en el período del estudio fue de 18-21ºC. Tres plantas fueron extraídas diariamente y se detuvo la extracción 96h después de haberse observado las primeras hembras adultas con huevos en la matriz gelatinosa. Entre 7 y 10 días posteriores a la inoculación, las raíces del tomate mostraron zonas hinchadas, indicativo de la entrada de los juveniles y de su alimentación. El ciclo de vida, desde J2 a hembra con matriz gelatinosa y huevos fue de 24 días. Las hembras en las primeras 24 horas depositaron más de 50 huevos en las matrices y a las 96h, tenían como promedio más de 100 huevos cada una. Abstract in english The experiment was carried out under semi controlled conditions in biological insulators (18-21ºC), with the objective of determining the duration of the life cycle of Meloidogyne incognita (Kofoid & White) Chitwood and the egg production of the adult females on tomato (Solanum lycopersicum L.) in t [...] he first 96h. Plants with about 15cm of height were transplanted to pots and, a week later, inoculated with 2500 ±5 J2 of M. incognita race 2. At 72 hours, they were removed and planted in pots with sterile soil. The root system was drawn out six days after inoculation to observe the different stages. The average temperature during the study was 18 to 21ºC. Three plants were removed and the daily extraction was stopped 96 h after the first adult females with eggs in the gelatinous matrix were observed. Between 7 and 10 days after inoculation, the roots of tomato showed swollen areas, indicative of the entrance of the juveniles and their feeding. The life cycle from J2 to female eggs with gelatinous matrix was 24 days. In the first 24 hours, the females deposited over 50 eggs in the wombs, and at 96h, each of them had an average of eggs higher than 100.

Dainé, Hernández-Ochandía; Yailén, Arias; Lucila, Gómez; Belkis, Peteira; Ileana, Miranda; Mayra G, Rodríguez.

2012-12-01

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Responses of Cotton Yield and Meloidogyne incognita Soil Populations to Soil Applications of Aldicarb and 1,3-D in Florida.  

Science.gov (United States)

In four tests conducted in loamy-sand soils in northern Florida, cotton lint yield increased and post-harvest soil populations of Meloidogyne incognita were more effectively suppressed by 1,3-dichloropropene (1,3-D) than aldicarb when both nematicides were evaluated over a range of recommended rates. Significant positive relationships existed between lint yield and rates of 1,3-D in three tests, whereas only one significant positive relationship occurred between lint yield and aldicarb rates. Yield increases ranged from 16% to 124%, depending on rate of 1,3-D, and 35% in one aldicarb-treated test. Only a weak negative relationship between post-harvest soil densities of second-stage juveniles (J2) and aldicarb rates was determined by combining data from the four tests. Aldicarb failed to suppress post-harvest J2 soil population densities in any test. All rates of 1,3-D significantly reduced post-harvest M. incognita J2 soil population densities in two tests and provided a stronger negative correlation between nematode soil densities and rates than aldicarb when all test data were combined for each nematicide. PMID:19274259

Kinloch, R A; Rich, J R

1998-12-01

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Adaptação hospedeira de variedades de abacaxi a meloidogyne incognita raça 1 / Host suitability of pineapple varieties for meloidogyne incognita race 1  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Avaliou-se, em campo naturalmente infestado, a adaptação hospedeira das variedades de abacaxi Smooth Cayenne, Abacaxi-de-gomo, Bico-de-rosa, Boituva, Guiana, Huitota, Manzana, Natal Queen, Pérola, Perolera, Rondon, Roxo-de-Tefé e Turi Verde a Meloidogyne incognita raça 1. Somente 'Huitota' apresento [...] u populações do nematóide significativamente menores que aquelas encontradas na 'Smooth Cayenne', considerada boa hospedeira da espécie. Abstract in english The host suitability of thirteen pineapple varieties, namely Smooth Cayenne, Abacaxi-de-gomo, Bico-de-rosa. Boituva, Guiana, Huitota, Manzana, Natal Queen, Pérola, Perolera, Rondon, Roxo-de-Tefé, and Turi Verde, for Meloidogyne incognita race I was evaluated under infested field conditions. Only 'Hu [...] itota' was considered poor host, showing significantly lower nematode population than 'Smooth Cayenne', known as a good host to M. incognita.

Leila Lucí, Dinardo-Miranda; Ademar, Spironello; Antonio Lúcio Mello, Martins.

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Adaptação hospedeira de variedades de abacaxi a meloidogyne incognita raça 1 Host suitability of pineapple varieties for meloidogyne incognita race 1  

Directory of Open Access Journals (Sweden)

Full Text Available Avaliou-se, em campo naturalmente infestado, a adaptação hospedeira das variedades de abacaxi Smooth Cayenne, Abacaxi-de-gomo, Bico-de-rosa, Boituva, Guiana, Huitota, Manzana, Natal Queen, Pérola, Perolera, Rondon, Roxo-de-Tefé e Turi Verde a Meloidogyne incognita raça 1. Somente 'Huitota' apresentou populações do nematóide significativamente menores que aquelas encontradas na 'Smooth Cayenne', considerada boa hospedeira da espécie.The host suitability of thirteen pineapple varieties, namely Smooth Cayenne, Abacaxi-de-gomo, Bico-de-rosa. Boituva, Guiana, Huitota, Manzana, Natal Queen, Pérola, Perolera, Rondon, Roxo-de-Tefé, and Turi Verde, for Meloidogyne incognita race I was evaluated under infested field conditions. Only 'Huitota' was considered poor host, showing significantly lower nematode population than 'Smooth Cayenne', known as a good host to M. incognita.

Leila Lucí Dinardo-Miranda

1996-01-01

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Toxicidade de filtrados fúngicos a meloidogyne incognita Fungus filtrates toxicity to Meloidogyne incognita  

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Full Text Available Visando à obtenção de novas moléculas nematicidas, 18 filtrados de espécies fúngicas e extratos de sete micélios fúngicos foram estudados in vitro quanto aos efeitos sobre a eclosão, motilidade e mortalidade de juvenis do segundo estádio (J2 de Meloidogyne incognita. Filtrados fúngicos foram obtidos de culturas em meio Czapek. Metanol foi usado como solvente para obter extratos dos micélios fúngicos. Filtrados de Paecilomyces lilacinus, Fusarium moniliforme e Fusarium oxysporum reduziram a motilidade e eclosão, e aumentaram a mortalidade (P In the search for new nematicidal molecules, 18 fungal species filtrates and seven fungus mycelium extracts were studied in vitro to see their influence on hatching, mobility and mortality of second stage juveniles (J2 of Meloidogyne incognita. Fungal filtrates were obtained from fifteen day Czapek cultures. Methanol was used as solvent to obtain fungus mycelium extracts. Paecilomyces lilacinus, Fusarium moniliforme and Fusarium oxysporum filtrates reduced J2 motility and hatching, and increased J2 mortality (P < 0,05 similarly to Aldicarb. Some fungus filtrates reduced J2 mobility without leading to death. Aspergillus flavus, Cylindrocarpon magnusianum, Fusarium solani and Mortierella sp. filtrates reduced (P < 0,05 only J2 hatching. Production of toxic fungus metabolites was not dependent on the amount of mycelium produced. P. lilacinus produced toxic filtrates after one day culturing. Since then, toxicity increased steadily, reaching 100% J2 mortality on the thirteenth day.

MAURO J.N. COSTA

2001-12-01

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Toxicidade de filtrados fúngicos a meloidogyne incognita / Fungus filtrates toxicity to Meloidogyne incognita  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Visando à obtenção de novas moléculas nematicidas, 18 filtrados de espécies fúngicas e extratos de sete micélios fúngicos foram estudados in vitro quanto aos efeitos sobre a eclosão, motilidade e mortalidade de juvenis do segundo estádio (J2) de Meloidogyne incognita. Filtrados fúngicos foram obtido [...] s de culturas em meio Czapek. Metanol foi usado como solvente para obter extratos dos micélios fúngicos. Filtrados de Paecilomyces lilacinus, Fusarium moniliforme e Fusarium oxysporum reduziram a motilidade e eclosão, e aumentaram a mortalidade (P Abstract in english In the search for new nematicidal molecules, 18 fungal species filtrates and seven fungus mycelium extracts were studied in vitro to see their influence on hatching, mobility and mortality of second stage juveniles (J2) of Meloidogyne incognita. Fungal filtrates were obtained from fifteen day Czapek [...] cultures. Methanol was used as solvent to obtain fungus mycelium extracts. Paecilomyces lilacinus, Fusarium moniliforme and Fusarium oxysporum filtrates reduced J2 motility and hatching, and increased J2 mortality (P

MAURO J.N., COSTA; VICENTE P., CAMPOS; LUDWIG H., PFENNING; DENILSON F., OLIVEIRA.

2001-12-01

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Reação de genótipos de maracujazeiro a Meloidogyne incognita raça 3 e Meloidogyne javanica / Reaction of passion fruit genotypes to Meloidogyne incognita race 3 and Meloidogyne javanica  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese O objetivo do trabalho foi avaliar a reação de genótipos de maracujazeiro a Meloidogyne spp.. O experimento foi conduzido em casa de vegetação em DBC, com seis repetições, em esquema fatorial 9x2 (Passiflora giberti, P. nitida, P. setacea, P. mucronata, P. cincinnata, P. ligularis, P.alata, híbrido [...] BRS Sol do Cerrado e seleção M19-UFV x Meloidogyne javanica e M. incognita raça 3). Segundo os critérios de Oostenbrink, e Moura e Régis, o BRS Sol do Cerrado, a seleção M-19-UFV e P. alata comportaram-se como imunes a M. incognita. Além destes, P. cincinnata e P. setacea foram imunes a M. javanica. Passiflora cincinnata e P.giberti comportaram-se como resistentes a M. incognita e M. javanica, respectivamente. Segundo Taylor e Sasser, os genótipos classificados como imunes pelos outros critérios foram classificados como resistentes aos nematoides. Todas as variáveis nematológicas avaliadas em P. giberti, P. ligularis, P. mucronata e P. nitida foram superiores em plantas infectadas por M. incognita. Independentemente do nematoide, P. mucronata apresentou maior número de galhas, massas de ovos, ovos, J2 e FR, em relação aos outros genótipos. O peso de matéria fresca de raiz de P. ligularis e P. mucronata foi menor na presença de M. incognita em relação a M. javanica. Abstract in english The aim of this study was to evaluate the reaction of genotypes of passion fruit to Meloidogyne spp.. The experiment was carried out in a greenhouse in RBD with six replications in 9 x 2 factorial designs (Passiflora giberti, P. nitida, P. setacea, P. mucronata, P. cincinnata, P. ligularis, P. alata [...] , BRS Sol do Cerrado cultivar and selection M19-UFV x Meloidogyne javanica and M. incognita race 3). According to Oostenbrink criteria, and Moura and Régis, the BRS Sol do Cerrado, and selection M-19-UFV and P. alata behaved as immune to M. incognita. In addition to these, P. cincinnata and P. setacea were immune to M. javanica. Passiflora cincinnata and P.giberti behaved as resistant to M. incognita and M. javanica, respectively. According to Taylor and Sasser, the genotypes classified as immune by the other criteria were classified as resistant to nematodes. All the nematological variables evaluated in P. giberti, P. ligularis, P. mucronata and P. nitida were superior in plants infected by M. incognita. Regardless of the nematode, P mucronata presented larger number of root galls, egg masses, eggs, J2 and RF, as compared to the other genotypes. The root fresh matter weight of P. ligularis and P. mucronata was smaller in the presence of M. incognita as compared to M. javanica.

Leandro Souza, Rocha; Regina Cássia Ferreira, Ribeiro; Adelica Aparecida, Xavier; Fabíola de Jesus, Silva; Claudio Horst, Bruckner.

1017-10-01

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Development of virulence to Meloidogyne incognita on resistant pepper rootstocks  

Energy Technology Data Exchange (ETDEWEB)

The root-knot nematode (RKN) Meloidogyne incognita is a major soil parasite of pepper crops in greenhouses in Southeast Spain. Due to the limitations of the use of soil fumigants, grafting plants on resistant rootstocks (R-rootstocks) has become an important alternative to chemical nematicides. The repeated use of R-rootstocks can bring about the selection of virulent populations capable of overcoming resistance. We carried out a six-year investigation on resistant rootstocks in a naturally M. incognita infested greenhouse, and found that two successive years of growing plants grafted on R-rootstocks Atlante (ATL) were sufficient to overcome resistance (galling index 1.5 and 5.6 in the first and second years respectively). A large variability was observed between several R-rootstocks. Two R-rootstocks (C19 and Snooker) behaved like ATL while two others (Terrano and DRO 8801) were not infected by RKN. Laboratory studies with the same R-rootstocks, inoculated with two nematode isolates (avirulent and virulent against ATL) confirmed the greenhouse results, indicating that some rootstocks may be infested by virulent populations and others may not. It suggests that different R-genes, which are differentially overcome by RKN, have been introgressed into the rootstocks. This may have consequences for the management of resistant rootstocks in the field. (Author)

Ros-Ibanez, C.; Robertson, L.; Martinez-Lluch, M. C.; Cano-Garcia, A.; Lacasa-Plasencia, A.

2014-06-01

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GENOTYPIC DIVERSITY OF POTATO GERMPLASM AGAINST ROOT KNOT NEMATODE (MELOIDOGYNE INCOGNITA INFECTION IN PAKISTAN  

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Full Text Available Potato (Solanum tuberosum, an important vegetable crop of Pakistan endures significant yield losses due to root knot nematode (Meloidogyne incognita.. Research wok was designed to identify resistant potato germplasm against RKN (Meloidogyne incognita infection. A field trial was conducted in the research area of Department of Plant Pathology, University of Agriculture Faisalabad. Thirty six (36 potato verities/ cultivars relocated five times were sown in four years sick plot containing root knot nematode (Meloidogyne incognita in RCBD layout. Root knot nematode reproduction and host damage was accessed by recording nematode root galls and egg mass indices, root weight, shoot weight, , number of leaves, fruit weight, rate of reproduction and final population of nematodes. Experiment revealed a considerable variation in response against Meloidogyne incognita infection among the genotype tested but none of the single cultivar was immune. FD-8-1 was used as negative control. The cultivar FD-19-2 was highly susceptible followed by SH-692 and SH-5. All other cultivars had less galling index with low fecundity rate indicating their ability to suppress the adult female reproduction. The cultivar FD-1-3 scored least number of galls and egg mass indices followed by FD-49-62, SH-339 and SH-332.

Sajid A. Khan

2012-12-01

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Reação de genótipos de Avena spp. a Meloidogyne incognita raça 4 Host suitability of Avena spp. genotypes to Meloidogyne incognita race 4  

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Full Text Available As aveias preta (Avena strigosa, branca (A. sativa e amarela (A. byzantina são muito utilizadas como culturas de cobertura, em sucessão a soja, algodão, feijão, batata e cenoura, que são culturas que sofrem elevadas perdas provocadas por Meloidogyne incognita. O manejo de M. incognita pode ter como um dos componentes o uso de genótipos de aveia que reduzam a densidade populacional do nematóide. Foram conduzidos três experimentos em casa de vegetação com o objetivo de avaliar cinco genótipos de aveia preta ('CPAO 0010', 'Comum', 'Embrapa 29', 'Embrapa 140' e 'IPFA 99006', um de aveia branca ('UFRGS 17' e um de aveia amarela ('São Carlos', em relação a sua resposta a três isolados da raça 4 de M. incognita (BA, SP e MT. As aveias pretas aumentaram a densidade populacional do nematóide. As aveias branca e amarela reduziram ou causaram pequeno aumento da densidade populacional de M. incognita, não se diferenciando de Crotalaria spectabilis. Portanto, a aveia branca 'UFRGS 17' e a amarela 'São Carlos' devem ser preferidas em relação às aveias pretas como culturas de cobertura, em áreas infestadas com M. incognita raça 4.The black oat (Avena strigosa, the white oat (A. sativa and the Algerian oat (A. byzantina have been widely used as cover crops under succession with soybean, cotton, bean, potato and carrot, which are crops highly damaged by Meloidogyne incognita. The management of M. incognita may have as a component the use of oat genotypes that reduce the nematode population density. Three greenhouse experiments were carried out in order to evaluate the host suitability of five genotypes of black oat ('CPAO 0010', 'Common', 'Embrapa 29', 'Embrapa 140' and 'IPFA 99006', one of white oat ('UFRGS 17' and one of Algerian oat ('São Carlos' to three isolates of M. incognita race 4 (BA, SP and MT. The black oats increased the population density of the nematode. The oats 'UFRGS 17' and 'São Carlos' reduced or caused a small increase in the population of M. incognita race 4, and neither differentiated from Crotalaria spectabilis. Therefore, the white oat 'UFRGS 17' and the Algerian oat 'São Carlos' should be used in preference to black oats as cover crops in areas infested with M. incognita race 4.

Dárcio C. Borges

2009-02-01

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Reação de genótipos de Avena spp. a Meloidogyne incognita raça 4 / Host suitability of Avena spp. genotypes to Meloidogyne incognita race 4  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese As aveias preta (Avena strigosa), branca (A. sativa) e amarela (A. byzantina) são muito utilizadas como culturas de cobertura, em sucessão a soja, algodão, feijão, batata e cenoura, que são culturas que sofrem elevadas perdas provocadas por Meloidogyne incognita. O manejo de M. incognita pode ter co [...] mo um dos componentes o uso de genótipos de aveia que reduzam a densidade populacional do nematóide. Foram conduzidos três experimentos em casa de vegetação com o objetivo de avaliar cinco genótipos de aveia preta ('CPAO 0010', 'Comum', 'Embrapa 29', 'Embrapa 140' e 'IPFA 99006'), um de aveia branca ('UFRGS 17') e um de aveia amarela ('São Carlos'), em relação a sua resposta a três isolados da raça 4 de M. incognita (BA, SP e MT). As aveias pretas aumentaram a densidade populacional do nematóide. As aveias branca e amarela reduziram ou causaram pequeno aumento da densidade populacional de M. incognita, não se diferenciando de Crotalaria spectabilis. Portanto, a aveia branca 'UFRGS 17' e a amarela 'São Carlos' devem ser preferidas em relação às aveias pretas como culturas de cobertura, em áreas infestadas com M. incognita raça 4. Abstract in english The black oat (Avena strigosa), the white oat (A. sativa) and the Algerian oat (A. byzantina) have been widely used as cover crops under succession with soybean, cotton, bean, potato and carrot, which are crops highly damaged by Meloidogyne incognita. The management of M. incognita may have as a com [...] ponent the use of oat genotypes that reduce the nematode population density. Three greenhouse experiments were carried out in order to evaluate the host suitability of five genotypes of black oat ('CPAO 0010', 'Common', 'Embrapa 29', 'Embrapa 140' and 'IPFA 99006'), one of white oat ('UFRGS 17') and one of Algerian oat ('São Carlos') to three isolates of M. incognita race 4 (BA, SP and MT). The black oats increased the population density of the nematode. The oats 'UFRGS 17' and 'São Carlos' reduced or caused a small increase in the population of M. incognita race 4, and neither differentiated from Crotalaria spectabilis. Therefore, the white oat 'UFRGS 17' and the Algerian oat 'São Carlos' should be used in preference to black oats as cover crops in areas infested with M. incognita race 4.

Dárcio C., Borges; Sonia R., Antedomênico; Viviane P., Santos; Mário M., Inomoto.

2009-02-01

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Winter Survival of Meloidogyne incognita in Six Soil Types  

OpenAIRE

Winter survival of Meloidogyne incognita in six soil types (Fuquay sand, Norfolk loamy sand, Portsmouth loamy sand, muck, Cecil sandy clay loam, and Cecil sandy clay) was determined in microplots at one location from November 1981 to May 1982 and from November 1982 to March 1983. Survival, based on second-stage juveniles (J2) of M. incognita, from November 1981 until May 1982 ranged from 1% in the muck soil to 6% in a Cecil sandy clay loam, but survival rates were much higher the next year fo...

Windham, G. L.; Barker, K. R.

1988-01-01

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Potential for Site-specific Management of Meloidogyne incognita in Cotton Using Soil Textural Zones  

OpenAIRE

The effect of various edaphic factors on Meloidogyne incognita population densities and cotton yield were evaluated from 2001 to 2003 in a commercial cotton field in southeastern Arkansas. The 6.07-ha field was subdivided into 512 plots (30.5 m × 3.9 m), and each plot was sampled for M. incognita prior to fumigation (Ppre), at planting (Pi), at peak bloom (Pm) and at harvest (Pf) each year. Soil texture (percent sand fraction) and the pre-plant soil fertility levels each year were determined...

Monfort, W. S.; Kirkpatrick, T. L.; Rothrock, C. S.; Mauromoustakos, A.

2007-01-01

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Effects of 1,3-Dicliloropropene for Meloidogyne incognita Management on Cotton Produced under Furrow Irrigation.  

Science.gov (United States)

Field trials were conducted during 1990 to evaluate the effects of preplant soil fumigation with 1,3-dichloropropene (1,3-D) on yield and fiber quality of furrow-irrigated cotton cultivars subjected to high population densities of Meloidogyne incognita. We measured the responses of eight upland cotton cultivars with different levels of root-knot nematode resistance and compared the responses of upland and Pima cottons. Reductions in lint weight ranged from 10 to 52% among cultivars grown in soil without 1,3-D fumigation compared with those grown in treated soil. Meloidogyne incognita reduced yields primarily by reducing the number of bolls on each plant, rather than by decreasing boll size. Cotton fiber quality varied among cultivars but was unaffected by M. incognita in either study. Upland cotton cultivar Acala 1517-88 and M-315/240 sustained less than half the yield reductions observed with M. incognita-susceptible cultivars Deltapine 41 and Paymaster 145. Sixty days after cotton emergence, fewer M. incognita second-stage juveniles were recovered from M-315/240 than all other cultivars. PMID:19279835

Thomas, S H; Smith, D W

1993-12-01

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Efeitos do nível de inóculo de Meloidogyne incognita em algodoeiro  

OpenAIRE

Pesquisas acerca da fisiologia de plantas em resposta ao ataque de nematóides normalmente são feitas com doses altas de inóculo, quer sejam ovos ou juvenis de segundo estágio. Diferentemente, as avaliações da resistência de plantas a nematóides em programas de melhoramento são realizadas com doses bastante inferiores. Neste estudo acompanhou-se a variação de alguns parâmetros fisiológicos em algodão, em resposta à aplicação de baixas doses de inóculo de Meloidogyne incognita...

ABRÃO MARLUCI MUNDIN; MAZZAFERA PAULO

2001-01-01

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Sensitivity of Meloidogyne incognita and Rotylenchulus reniformis to Abamectin  

OpenAIRE

Avermectins are macrocyclic lactones produced by Streptomyces avermitilis. Abamectin is a blend of B1a and B1b avermectins that is being used as a seed treatment to control plant-parasitic nematodes on cotton and some vegetable crops. No LD50 values, data on nematode recovery following brief exposure, or effects of sublethal concentrations on infectivity of the plant-parasitic nematodes Meloidogyne incognita or Rotylenchulus reniformis are available. Using an assay of nematode mobility, LD50 ...

Faske, T. R.; Starr, J. L.

2006-01-01

31

Effects of 1,3-Dicliloropropene for Meloidogyne incognita Management on Cotton Produced under Furrow Irrigation  

OpenAIRE

Field trials were conducted during 1990 to evaluate the effects of preplant soil fumigation with 1,3-dichloropropene (1,3-D) on yield and fiber quality of furrow-irrigated cotton cultivars subjected to high population densities of Meloidogyne incognita. We measured the responses of eight upland cotton cultivars with different levels of root-knot nematode resistance and compared the responses of upland and Pima cottons. Reductions in lint weight ranged from 10 to 52% among cultivars grown in s...

Thomas, S. H.; Smith, D. W.

1993-01-01

32

Induction of Systemic Acquired Resistance by Rotylenchulus reniformis and Meloidogyne incognita in Cotton Following Separate and Concomitant Inoculations  

OpenAIRE

Systemic acquired resistance (SAR) can be elicited by virulent and avirulent pathogenic strains and SAR against plant-parasitic nematodes has been documented. Our objective was to determine whether co-infection of cotton by Meloidogyne incognita and Rotylenchulus reniformis affects the population level of either nematode compared to infection by each species individually. Split-root trials were conducted in which plants were inoculated with i) R. reniformis only, ii) M. incognita only, iii) b...

Aryal, Sudarshan K.; Davis, Richard F.; Stevenson, Katherine L.; Timper, Patricia; Ji, Pingsheng

2011-01-01

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Reaction of common bean genotypes to Meloidogyne incognita Race 1 / Reação do plantas de feijoeiro a Meloidogyne incognita Raça 1  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: English Abstract in portuguese RESUMO Objetivou-se com esse trabalho estudar a reação de 33 genótipos de Phaseolus vulgaris L. ao parasitismo de Meloidogyne incognita raça 1 em casa de vegetação. Desses genótipos seis são cultivados comercialmente ("IAPAR­- 81" , "EL- 22" , "Carioca", "Serrano", "BATT- 477" e "Uirapuru"), um é su [...] scetível ("Rico- 23" ), dois são resistentes ("Aporé" e "Pérola") e os demais foram resgatados em propriedades localizadas no Sul do Espírito Santo. O experimento foi conduzido em casa de vegetação em delineamento inteiramente casualisado com 7 repetições. As plantas foram inoculadas com 4.000 ovos + juvenis de segundo estádio (J2) do nematóide. Após 50 dias da inoculação, foram avaliados a população final de nematóides (PF), fator de reprodução (FR) e o percentual de redução do fator de reprodução (% RFR). Os genótipos foram classificados como altamente susceptível (AS), susceptível (SU), pouco resistente (PR), moderadamente resistente (MR), resistente (RE), altamente resistente (AR) ou imune (IM). Apenas o genótipo "Preto Meia Lua" comportou-se como AR. Os genótipos "Terrinha- 2" e "Mulatinho" foram classificados como RE, os genótipos "EL- 22", "BATT- 477", "Vermelho", "Bate Estrada" e "Paina" como SU e os genótipos "Rico- 23" e "Morgado" como AS. Abstract in english ABSTRACT The objective was to determine the reaction of 33 Phaseolus vulgaris L. genotypes to parasitism by Meloidogyne incognita race 1. The genotypes used in this study six included commercially exploited ("IAPAR­- 81", "EL- 22", "Carioca", "Serrano", "BATT- 477" and "Uirapuru") varieties, one sus [...] ceptible ("Rico- 23") and two resistant ("Aporé" and "Pérola") varieties; the others were provided by farmers of the South of Espírito Santo State. The experiment was carried out in a greenhouse in a completely randomized design with 7 replicates. The plants were inoculated with 4,000 eggs + second-stage juveniles (J2) of nematodes. After 50 days, the final population of nematodes (FP), reproduction factor (RF) and percentage reproduction rate (%RR) were evaluated. The resistance selection was based on the %RR, i.e., 0-25% = highly susceptible (HS); 26-50% = susceptible (SU); 51-75% = little resistant (LR); 76-95% = moderately resistant (MR); 96-99% = resistant (RE); 100% = highly resistant (HR) or immune (IM). Only the genotype "Preto Meia Lua" was highly resistant. The genotypes "Terrinha- 2" and "Mulatinho" were classified as resistant, "EL- 22", "BATT- 477", "Vermelho", "Bate Estrada" and "Paina" as (susceptible) and genotypes "Rico 23" and "Morgado" as highly susceptible.

Fábio R, Alves; Leonardo N. S, dos Santos; Willian B, Moraes; Fernando C, Cosmi; Pablo D. S, Cabral; Sebastião Martins, Filho; Frederico De Pina, Matta; Waldir C. Jesus, Júnior.

2011-08-01

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Reaction of common bean genotypes to Meloidogyne incognita Race 1 Reação do plantas de feijoeiro a Meloidogyne incognita Raça 1  

Directory of Open Access Journals (Sweden)

Full Text Available ABSTRACT The objective was to determine the reaction of 33 Phaseolus vulgaris L. genotypes to parasitism by Meloidogyne incognita race 1. The genotypes used in this study six included commercially exploited ("IAPAR­- 81", "EL- 22", "Carioca", "Serrano", "BATT- 477" and "Uirapuru" varieties, one susceptible ("Rico- 23" and two resistant ("Aporé" and "Pérola" varieties; the others were provided by farmers of the South of Espírito Santo State. The experiment was carried out in a greenhouse in a completely randomized design with 7 replicates. The plants were inoculated with 4,000 eggs + second-stage juveniles (J2 of nematodes. After 50 days, the final population of nematodes (FP, reproduction factor (RF and percentage reproduction rate (%RR were evaluated. The resistance selection was based on the %RR, i.e., 0-25% = highly susceptible (HS; 26-50% = susceptible (SU; 51-75% = little resistant (LR; 76-95% = moderately resistant (MR; 96-99% = resistant (RE; 100% = highly resistant (HR or immune (IM. Only the genotype "Preto Meia Lua" was highly resistant. The genotypes "Terrinha- 2" and "Mulatinho" were classified as resistant, "EL- 22", "BATT- 477", "Vermelho", "Bate Estrada" and "Paina" as (susceptible and genotypes "Rico 23" and "Morgado" as highly susceptible.RESUMO Objetivou-se com esse trabalho estudar a reação de 33 genótipos de Phaseolus vulgaris L. ao parasitismo de Meloidogyne incognita raça 1 em casa de vegetação. Desses genótipos seis são cultivados comercialmente ("IAPAR­- 81" , "EL- 22" , "Carioca", "Serrano", "BATT- 477" e "Uirapuru", um é suscetível ("Rico- 23" , dois são resistentes ("Aporé" e "Pérola" e os demais foram resgatados em propriedades localizadas no Sul do Espírito Santo. O experimento foi conduzido em casa de vegetação em delineamento inteiramente casualisado com 7 repetições. As plantas foram inoculadas com 4.000 ovos + juvenis de segundo estádio (J2 do nematóide. Após 50 dias da inoculação, foram avaliados a população final de nematóides (PF, fator de reprodução (FR e o percentual de redução do fator de reprodução (% RFR. Os genótipos foram classificados como altamente susceptível (AS, susceptível (SU, pouco resistente (PR, moderadamente resistente (MR, resistente (RE, altamente resistente (AR ou imune (IM. Apenas o genótipo "Preto Meia Lua" comportou-se como AR. Os genótipos "Terrinha- 2" e "Mulatinho" foram classificados como RE, os genótipos "EL- 22", "BATT- 477", "Vermelho", "Bate Estrada" e "Paina" como SU e os genótipos "Rico- 23" e "Morgado" como AS.

Fábio R Alves

2011-08-01

35

Reação de porta-enxertos de pessegueiro à Meloidogyne incognita Reaction of peach rootstocks to Meloidogyne incognita  

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Full Text Available O objetivo foi avaliar a reação de cinco porta-enxertos de pessegueiro ao Meloidogyne incognita (Kofoid e White Chitwood, em condições de casa de vegetação. Foram utilizados os porta-enxertos: 'Seleção UFPel 0402', 'Okinawa', 'Nagano Wild', 'Flordaguard' e 'Seleção NR-0080407'. As plantas foram inoculadas com 10.000 ovos+J2 de Meloidogyne incognita. Cinco plantas de tomateiro cv. Santa Cruz foram inoculadas para comprovação da eficiência do inóculo. O delineamento experimental foi o inteiramente casualizado, com cinco repetições e uma planta por parcela. Seis meses após a inoculação, as raízes foram avaliadas quanto ao índice de galhas e ao Fator de Reprodução (FR. No tomateiro, as avaliações foram feitas aos três meses após a inoculação. Não se verificou a ocorrência de galhas ou multiplicação dos nematoides nos genótipos avaliados, com exceção do porta-enxerto 'Nagano Wild', onde se registraram 36 galhas, porém sem evidência de multiplicação do nematoide. Os genótipos testados foram considerados imunes a esta espécie de nematoide das galhas, uma vez que foram eficazes em suprimir a reprodução de M. incognita, podendo ser usados como porta-enxertos alternativos em áreas de plantio com ocorrência desta praga de solo ou como fonte de resistência ao melhoramento genético de porta-enxertos de pessegueiro.In order to evaluate the reaction of the peach rootstocks 'Okinawa', 'Flordaguard', 'Nagano Wild', and the selection 'UFPel 0402' and 'NR-0080407' to Meloidogyne incognita, the plants were inoculated with 10.000 eggs+J2 of M. incognita. Seedlings of tomato 'Santa Cruz' inoculated in the same way were used as control and to determine the inoculum viability. The experiment was carried out under greenhouse conditions in a completely randomized experimental design with five replications, each one performe by a plant. Six months after inoculation, the plants were pulled out on the roots and evaluated for the number of galls and reproduction factor (RF. Neither gall no nematode reproduction was registered in all rootstock systems, except for 'Nagano Wild' that shown 36 galls, but without evidences of nematode reproduction. All the tested genotypes were considered immune to this root-knot nematode specie, because they were effective in suppressing the M. incognita reproduction, and may be used as alternative rootstocks in new orchards or as resistance source to genetic improvement of peach rootstock.

Luciane Arantes de Paula

2011-06-01

36

Cyperus Tubers Protect Meloidogyne incognita from 1,3-Dichloropropene.  

Science.gov (United States)

Meloidogyne incognita-infected and noninfected tubers of yellow nutsedge (Cyperus esculentus) and purple nutsedge (Cyperus rotundus) were treated with 56 L/ha 1,3-dichloropropene (1,3-D) in microplots and subsequently examined for tuber and nematode viability in the greenhouse using a chile pepper (Capsicum annuum) bioassay system. The study was conducted three times. Nutsedge tuber viability and M. incognita harbored in both yellow and purple nutsedge tubers were unaffected by 1,3-D treatment. Nematode reproduction on nutsedges and associated chile pepper plants varied among years, possibly due to differing levels of tuber infection or soil temperature, but was not affected by fumigation. The presence of M. incognita resulted in greater yellow nutsedge tuber germination and reproduction. The efficacy of 1,3-D for management of M. incognita in chile pepper production is likely to be reduced when nutsedges are present in high numbers, reinforcing the importance of managing these weeds and nematodes simultaneously. PMID:19262797

Thomas, S H; Schroeder, J; Murray, L W

2004-06-01

37

Identificación morfológica, morfométrica y molecular de meloidogyne incognita en higuera (ficus carica l.) en Costa Rica  

Scientific Electronic Library Online (English)

Full Text Available SciELO Costa Rica | Language: Spanish Abstract in spanish Identificación morfológica, morfométrica y molecular de Meloidogyne incognita en higuera (Ficus carica L.) en Costa Rica. El objetivo de este estudio fue identificar la especie de Meloidogyne asociada a dos plantaciones de higuera en Costa Rica. En marzo de 2012, en el distrito de Pacayas, provincia [...] de Cartago, se detectaron agallas en los sistemas radicales de plantas de higuera (Ficus carica L.) de dos fincas. De las raíces agalladas se extrajeron hembras, masas de huevos y juveniles (J2) de Meloidogyne sp. Se examinaron los patrones perineales de las hembras y los segundos estadios infectivos se analizaron morfológica y molecularmente mediante PCR-RFLP. Se amplificó la región intergénica (IGS) del genoma mitocondrial, delimitada por el gen de la subunidad II de la citocromo oxidasa (COII) y el gen ribosomal 16S. La población de nematodos se identificó como M. incognita. El tamaño de los productos de PCR generados con los imprimadores C2F3 y 1108 fue de 1,7 kb. Al tratar los productos de PCR con enzimas de restricción, se generaron cuatro fragmentos de 850, 450, 250 y 150 pb con la enzima AluI y dos fragmentos de 1300 y 400 pb con la enzima HinfI. Abstract in english Morphological, morphometrical and molecular identification of Meloidogyne incognita in fig (Ficus carica L.) in Costa Rica. The objective of this study was to identify species of Meloidogyne associated with two fig plantations in Costa Rica. On March 2012 in Pacayas, Cartago province, root-galls wer [...] e found in two fig plantations of Ficus carica L. Females, egg-masses and juveniles (J2) of Meloidogyne sp. were extracted from the galled roots. Female perineal patterns were examined and second infective stages were analyzed morphometrically and molecularly by PCR-RFLP. The mitochondrial intergenic region (IGS) flanked by the cytochrome oxidase subunit II gene (COII) and the 16S ribosomal gene was amplified. The population was identified morphologically, morphometrically and molecularly as M. incognita. The PCR product obtained with primers C2F3 and 1108 were 1.7 kb in size. When PCR products were treated with restriction enzymes they generated four fragments of 850, 450, 250 and 150 bp with AluI and two fragments of 1300 and 400 bp with HinfI.

Walter, Peraza-Padilla; Johaner, Rosales-Flores; Alejandro, Esquivel-Hernández; Irena, Hilje-Rodríguez; Ramón, Molina-Bravo; Pablo, Castillo-Castillo.

2013-12-01

38

Purificação de metabólitos fúngicos com efeitos tóxicos sobre Meloidogyne incognita / Purification of fungal metabolites with toxic effects on Meloidogyne incognita  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Objetivando o desenvolvimento de novas metodologias de controle de fitonematóides, este trabalho buscou purificar as substâncias nematicidas produzidas por Cunninghamella elegans, Fusarium sp., Paecilomyces lilacinus eP. variotii. Esses fungos foram cultivados em meio líquido Czapek-Dox durante 15 d [...] ias, a 25 ºC, em agitador orbital. Em seguida, filtraram-se as misturas, o que permitiu a obtenção de soluções que foram concentradas sob vácuo e submetidas à purificação direcionada por testes in vitro com Meloidogyne incognita. Observou-se que os filtrados de P. lilacinus e P. variotii perdiam suas atividades nematicidas após a concentração sob vácuo, sugerindo que as substâncias ativas produzidas por esses fungos são consideravelmente voláteis. Para o filtrado de Fusarium sp., observou-se perda total da atividade contra M. incognita após fracionamento em coluna de sílica gel, indicando instabilidade da substância nematicida frente às condições empregadas.Do filtrado de C. elegans isolou-se uma substância que, em solução aquosa na concentração de 250 ppm, imobilizou 94% dos juvenis do segundo estádio de M. incognita expostos a tal solução durante 48 h. Abstract in english In a search for new molecules toxic to plant parasitic nematodes, procedures were set up to purify nematode toxic molecules produced by Cunninghamella elegans, Fusarium sp., Paecilomyces lilacinus and P. variotii. Those fungi were grown in Czapek-Dox liquid medium during 15 days, at 25 ºC, in an orb [...] ital shaker. After fungus mycelium removal by filtration, the solutions were concentrated under vacuum and submitted to purification, guided by in vitro assays with Meloidogyne incognita juveniles. As a result, it was observed that P. lilacinus and P.variotii filtrates lost their activity after vacuum concentration, which suggests that the nematocides produced by those fungi are considerably volatile. In the case of Fusarium sp. filtrate, the active substance seems to be unstable, as the activity against M. incognita juveniles completely disappeared after chromatography in a silica gel column. The C. elegans filtrate rendered one isolated substance that immobilized 94% of the M. incognita juveniles exposed during 48 h to an aqueous solution of the substance at 250 ppm.

GERALDO H., SILVA; DENILSON F., OLIVEIRA; VICENTE P., CAMPOS.

2002-11-01

39

Alternate row placement is ineffective for cultural control of Meloidogyne incognita in cotton  

OpenAIRE

The objective of this study was to determine if planting cotton into the space between the previous year's rows reduces crop loss due to Meloidogyne incognita compared to planting in the same row every year. Row placement had a significant (P ? 0.05) effect on nematode population levels only on 8 July 2005. Plots receiving 1,3-dichloropropene plus aldicarb had lower nematode population levels than non-fumigated plots on 24 May and 8 July in 2005, but not in 2004. The effect of nematicide tr...

Davis, Richard F.

2008-01-01

40

Purificação de metabólitos fúngicos com efeitos tóxicos sobre Meloidogyne incognita  

Directory of Open Access Journals (Sweden)

Full Text Available Objetivando o desenvolvimento de novas metodologias de controle de fitonematóides, este trabalho buscou purificar as substâncias nematicidas produzidas por Cunninghamella elegans, Fusarium sp., Paecilomyces lilacinus eP. variotii. Esses fungos foram cultivados em meio líquido Czapek-Dox durante 15 dias, a 25 ºC, em agitador orbital. Em seguida, filtraram-se as misturas, o que permitiu a obtenção de soluções que foram concentradas sob vácuo e submetidas à purificação direcionada por testes in vitro com Meloidogyne incognita. Observou-se que os filtrados de P. lilacinus e P. variotii perdiam suas atividades nematicidas após a concentração sob vácuo, sugerindo que as substâncias ativas produzidas por esses fungos são consideravelmente voláteis. Para o filtrado de Fusarium sp., observou-se perda total da atividade contra M. incognita após fracionamento em coluna de sílica gel, indicando instabilidade da substância nematicida frente às condições empregadas.Do filtrado de C. elegans isolou-se uma substância que, em solução aquosa na concentração de 250 ppm, imobilizou 94% dos juvenis do segundo estádio de M. incognita expostos a tal solução durante 48 h.

SILVA GERALDO H.

2002-01-01

41

Influence of Environmental Factors on the Hatch and Survival of Meloidogyne incognita  

OpenAIRE

The influence of soil temperature and moisture on Meloidogyne incognita (Kofoid and White) Chitwood was examined in relation to hatching and survival of second-stage juveniles (J2). Nematodes were cultured on cotton (Gossypium hirsutum L. cv. Acala SJ2) under field conditions to provide populations similar to those found in the field in late autumn. Egg masses were placed in a temperature range (9-12 C and 21 C), and hatch was measured over a period equivalent to 20 degree days > 10 C (DD10)....

Goodell, P. B.; Ferris, H.

1989-01-01

42

Population Dynamics of Meloidogyne incognita, M. arenaria,and Other Nematodes and Crop Yields in Rotations of Cotton, Peanut, and Wheat Under Minimum Tillage  

OpenAIRE

Wheat, cotton, and peanut were arranged in three cropping sequences to determine the effects of fenamiphos (6.7 kg a.i./ha) and cropping sequence on nematode population densities and crop yields under conservation tillage and irrigation for 6 years. The cropping sequences included a wheat winter cover crop each year and summer crops of cotton every year, peanut every year, or cotton rotated every other year with peanut. The population densities of Meloidogyne spp. and Helicotylenchus dihyster...

Johnson, A. W.; Dowler, C. C.; Handoo, Z. A.

2000-01-01

43

Alternate row placement is ineffective for cultural control of Meloidogyne incognita in cotton.  

Science.gov (United States)

The objective of this study was to determine if planting cotton into the space between the previous year's rows reduces crop loss due to Meloidogyne incognita compared to planting in the same row every year. Row placement had a significant (P yield in 2004 or 2005. Nematicide treatment decreased root galling in all years, and the decrease was not influenced by row placement. Yield was increased by nematicide application in 2004 and 2005, and the increase was not affected by row placement. Percentage yield loss was not affected by row placement. Changing the placement of rows reduced nematode population levels only on one sampling date in one year, but end-of-season root galling and lint yield were not affected by changing the placement of rows, nor was the effect of fumigation on yield influenced by row placement. Therefore, row placement is unlikely to contribute to M. incognita management in cotton. PMID:19440259

Davis, Richard F

2008-09-01

44

Evaluation of Soybean Cultivars for Production in Meloidogyne incognita-infested Soil  

OpenAIRE

Significant (P < 0.05) differences among galling and yields of 41 soybean cultivars and breeding lines were found when they were produced at a site infested with Meloidogyne incognita during 3 years of investigation. Over a period of 6 years of testing, 13 cultivars were identified as having a suitably low susceptibility to warrant their production in M. incognita infested soil.

Kinloch, R. A.; Hiebsch, C. K.; Peacock, H. A.

1987-01-01

45

Management of Meloidogyne incognita with Chemicals and Cultivars in Cotton in a Semi-Arid Environment  

OpenAIRE

Management of Meloidogyne incognita (root-knot nematode) in cotton in the United States was substantially affected by the decision to stop production of aldicarb by its principle manufacturer in 2011. The remaining commercially available tools to manage M. incognita included soil fumigation, nematicide seed treatments, postemergence nematicide application, and cultivars partially resistant to M. incognita. Small plot field studies were conducted on a total of nine sites from 2011–2013 to ex...

Wheeler, T. A.; Siders, K. T.; Anderson, M. G.; Russell, S. A.; Woodward, J. E.; Mullinix, B. G.

2014-01-01

46

ASPECTOS GENERALES DE LA INTERACCIÓN TOMATE (Solanum lycopersicon L.) _ Meloidogyne incognita / General aspects of the interaction tomato (Solanum lycopersicon L.) _ Meloidogyne incognita  

Scientific Electronic Library Online (English)

Full Text Available En el presente trabajo se abordan aspectos generales de la interacción tomate-Meloidogyne incognita. Se tienen en cuenta especificidades morfológicas y fisiológicas propias de los nematodos como organismos causantes de enfermedades, mecanismos desarrollados por este grupo en el momento de la penetra [...] ción e infección y los mecanismos de defensa que desarrolla la planta. Abstract in english In this paper, general aspects of the interaction tomato-Meloidogyne incognita are summarized. The morphological and physiological specifications of nematodes as organisms causing diseases, the mechanisms developed by this group during penetration and infectation and the plant defense mechanisms are [...] analized.

Yailén, Arias; Ivonne, González; Mayra, Rodríguez; Carolina, Rosales; Zoraida, Suárez; Belkis, Peteira.

2009-04-01

47

Nematotoxic phenolic compounds from Melia azedarach against Meloidogyne incognita.  

Science.gov (United States)

In the present study, evaluated was the paralysis activity of whole Italian and Algerian Melia azedarach, commonly known as chinaberry, fruits and parts (seeds, wood, and kernels) against Meloidogyne incognita second stage juveniles (J(2)). The paralysis activity was evaluated in vitro after 1 h and 1 day immersion periods of nematodes in test solutions. Phenolic constituent components of the extracts were identified and quantified by high-performance liquid chromatography-mass spectrometry, while confirmation was performed by high-performance liquid chromatography-diode array. The water extract of the Italian M. azedarach fruit pulp (IPWE) showed significant nematicidal activity (EC(50/48h) = 955 ?g/mL) and among its active ingredient components were p-coumaric acid and p-hydroxybenzoic acid (EC(50/48h) = 840 and 871 ?g/mL, respectively). This is the first report of the nematicidal activity of M. azedarach pulp water extract and phenolic acids against the root knot nematode M. incognita. PMID:23136941

Aoudia, Hassiba; Ntalli, Nikoletta; Aissani, Nadhem; Yahiaoui-Zaidi, R; Caboni, Pierluigi

2012-11-28

48

Raphanus sativus, Sinapis alba, and Fagopyrum esculentum as Hosts to Meloidogyne incognita, Meloidogyne javanica, and Plasmodiophora brassicae  

OpenAIRE

Cultivars of oilseed radish (Raphanus sativus var. oleifera cv. Adagio, Nemex, Pegletta, Renova, Siletina, Siletta Nova, and Ultimo), white mustard (Sinapis alba cv. Albatross, Emergo, Maxi, Martigena, Metex, and Serval), buckwheat (Fagopyrum esculentum cv. Prego, Tardo), and phacelia (Phacelia tanacetifolia cv. Angelia) were tested for susceptibility to Meloidogyne incognita race 3 and Meloidogyne javanica. Experiments were conducted in growth chambers at 25 C and 16 hours light for 42 days ...

Gardner, J.; Caswell-chen, E. P.

1994-01-01

49

Effect of Broccoli (Brassica oleracea) Tissue, Incorporated at Different Depths in a Soil Column, on Meloidogyne incognita  

OpenAIRE

Brassicas have been used frequently for biofumigation, a pest-management strategy based on the release of biocidal volatiles during decomposition of soil-incorporated tissue. However, the role of such volatiles in control of plant-parasitic nematodes is unclear. The goal of this study was to determine the direct localized and indirect volatile effects of amending soil with broccoli tissue on root-knot nematode populations. Meloidogyne incognita-infested soil in 50-cm-long tubes was amended wi...

Roubtsova, Tatiana; Lo?pez-pe?r?ez, Jose-antonio; Edwards, Scott; Ploeg, Antoon

2007-01-01

50

Varietal Response of Tomato to the Interaction of Salinity and Meloidogyne incognita Infection  

OpenAIRE

Response of tomato (Lycopersicon esculentum) cultivars to a range of conductivity levels was tested in the presence and absence of Meloidogyne incognita. The conductivity levels were produced by appropriate adjustment of a 1:1 solution of sodium chloride and calcium chloride. The growth of M. incognita resistant ('Beefmaster' and 'Atkinson') and susceptible ('Hunts 2580' and 'Ronita') tomato plants was inversely related to soil salinity between ECe 0 and 5 mmhos/cm. Nematode inoculation of sa...

Edongali, Ezarug A.; Ferris, Howard

1982-01-01

51

Resistance induction for Meloidogyne incognita in sugarcane through mineral organic fertilizers  

OpenAIRE

The effects of Coda Radimax (CR), Coda Humus-PK (CH) and Coda Vit (CV) on the induction of resistance for Meloidogyne incognita in sugarcane (Saccharum sp.) varieties (RB92579, RB863129, RB867515) through nematode reproduction, plant development and root anatomy analysis, emphasizing the differences of the lignin deposition, and cortex-vascular cylinder proportions were investigated. In 90 days after inoculation with eggs of M. incognita, CR reduced the number of eggs per root system in all t...

Andréa Chaves; Elvira Maria Régis Pedrosa; Rejane Magalhães de Mendonça Pimentel; Rildo Sartori Barbosa Coelho; Lílian Margarete Paes Guimarães; Sandra Roberta Vaz Lira Maranhão

2009-01-01

52

Relationships between Soil and Levels of Meloidogyne incognita and Tobacco Yield and Quality  

OpenAIRE

A 2-year study with six soils and four levels of Meloidogyne incognita in microplots was designed to determine the effects of these parameters on nematode activity and tobacco yield and quality. Key components under study were affected by soil, nematode level, and season (year-cultivar). In 1980, low initial nematode numbers (1,250) enhanced tobacco yield in Cecil clay loam, but caused slight to moderate yield losses in the other soils. Yield losses to M. incognita were generally greatest in ...

Barker, K. R.; Weeks, W. W.

1991-01-01

53

Efficacy of Fenamiphos Formulations Applied through Irrigation for Control of Meloidogyne incognita on Squash  

OpenAIRE

Management ofMeloidogyne incognita by chemigation with fenamiphos was studied in an infested field planted to M. incognita-suscepfible yellow summer squash cv. Dixie Hybrid. Fenamiphos (VL 73.1% a.i. manufacturing concentrate in propylene glycol) was mixed with Unitol DSR-90 or used as fenamiphos 3 SC (spray concentrate). Both formulations, applied with 63.5 kl irrigation water per hectare, decreased numbers of M. incognita second-stage juveniles in the soil and root-gall indices, and increas...

Johnson, A. W.; Young, J. R.

1994-01-01

54

Efeitos do nível de inóculo de Meloidogyne incognita em algodoeiro Effects of low inoculum level of Meloidogyne incognita on cotton plants  

OpenAIRE

Pesquisas acerca da fisiologia de plantas em resposta ao ataque de nematóides normalmente são feitas com doses altas de inóculo, quer sejam ovos ou juvenis de segundo estágio. Diferentemente, as avaliações da resistência de plantas a nematóides em programas de melhoramento são realizadas com doses bastante inferiores. Neste estudo acompanhou-se a variação de alguns parâmetros fisiológicos em algodão, em resposta à aplicação de baixas doses de inóculo de Meloidogyne incognita...

MARLUCI MUNDIN ABRÃO; PAULO MAZZAFERA

2001-01-01

55

Adaptação hospedeira de variedades de abacaxi a meloidogyne incognita raça 1 Host suitability of pineapple varieties for meloidogyne incognita race 1  

OpenAIRE

Avaliou-se, em campo naturalmente infestado, a adaptação hospedeira das variedades de abacaxi Smooth Cayenne, Abacaxi-de-gomo, Bico-de-rosa, Boituva, Guiana, Huitota, Manzana, Natal Queen, Pérola, Perolera, Rondon, Roxo-de-Tefé e Turi Verde a Meloidogyne incognita raça 1. Somente 'Huitota' apresentou populações do nematóide significativamente menores que aquelas encontradas na 'Smooth Cayenne', considerada boa hospedeira da espécie.The host suitability of thirteen pineapple varieties...

Leila Lucí Dinardo-Miranda; Ademar Spironello; Antonio Lúcio de Mello Martins

1996-01-01

56

Control of Meloidogyne incognita Using Mixtures of Organic Acids.  

Science.gov (United States)

This study sought to control the root-knot nematode (RKN) Meloidogyne incognita using benign organo-chemicals. Second-stage juveniles (J2) of RKN were exposed to dilutions (1.0%, 0.5%, 0.2%, and 0.1%) of acetic acid (AA), lactic acid (LA), and their mixtures (MX). The nematode bodies were disrupted severely and moderately by vacuolations in 0.5% of MX and single organic acids, respectively, suggesting toxicity of MX may be higher than AA and LA. The mortality of J2 was 100% at all concentrations of AA and MX and only at 1.0% and 0.5% of LA, which lowered slightly at 0.2% and greatly at 0.1% of LA. This suggests the nematicidal activity of MX may be mostly derived from AA together with supplementary LA toxicity. MX was applied to chili pepper plants inoculated with about 1,000 J2, for which root-knot gall formations and plant growths were examined 4 weeks after inoculation. The root gall formation was completely inhibited by 0.5% MX and standard and double concentrations of fosthiazate; and inhibited 92.9% and 57.1% by 0.2% and 0.1% MX, respectively. Shoot height, shoot weight, and root weight were not significantly (P ? 0.05) different among all treatments and the untreated and non-inoculated controls. All of these results suggest that the mixture of the organic acids may have a potential to be developed as an eco-friendly nematode control agent that needs to be supported by the more nematode control experiments in fields. PMID:25506312

Seo, Yunhee; Kim, Young Ho

2014-12-01

57

Glucosinolate content and nematicidal activity of Brazilian wild mustard tissues against Meloidogyne incognita in tomato  

Science.gov (United States)

The wild mustard (Brassica juncea L.), an invasive weed of winter crops in Brazil, was evaluated for glucosinolate content of its plant tissues and nematicidal activity of its dry leaf meal (LM), whole seed meal (WSM) and hexane defatted seed meal (DSM) against Meloidogyne incognita on tomato plants...

58

Localization of Cuticular Binding Sites of Concanavalin A on Caenorhabditis elegans and Meloidogyne incognita  

OpenAIRE

Utilizing a Concanavalin A (Con A)-hemocyanin conjugate, the majority of cuticular Con A binding sites were shown to be localized on the head region of Caenorhabclitis elegans and Meloidogyne incognita. Secretions which apparently emanated from the amphids and inner labial papillae did not label.

Mcclure, Michael A.; Zuckerman, Bert M.

1982-01-01

59

Protease inhibition by Heterodera glycines cyst content: evidence for effects on the Meloidogyne incognita proteasome  

Science.gov (United States)

Proteases from Heterodera glycines and Meloidogyne incognita juveniles were inhibited by heat-stable content of H. glycines female cysts (HglCE), and by the plant polyphenol epigallocatechin gallate (EGCG). General protease activities detected using the nematode peptide KSAYMRFa were inhibited by EG...

60

RESPONSES OF HETERODERA GLYCINES AND MELOIDOGYNE INCOGNITA TO EXOGENOUSLY APPLIED NEUROMODULATORS  

Science.gov (United States)

The biogenic amines dopamine, octopamine and serotonin each have significant but differing effects on behavior in juveniles of the plant-parasitic nematodes Heterodera glycines and Meloidogyne incognita. Body movement frequency was increased 2-fold in H. glycines by 5mM dopamine (P = 0.00013), while...

61

Development of Multi-Component Transplant Mixes for Suppression of Meloidogyne incognita on Tomato (Lycopersicon esculentum)  

OpenAIRE

The effects of combinations of organic amendments, phytochemicals, and plant-growth promoting rhizobacteria on tomato (Lycopersicon esculentum) germination, transplant growth, and infectivity of Meloidogyne incognita were evaluated. Two phytochemicals (citral and benzaldehyde), three organic amendments (pine bark, chitin, and hemicellulose), and three bacteria (Serratia marcescens, Brevibacterium iodinum, and Pseudomonas fluorescens) were assessed. Increasing rates of benzaldehyde and citral ...

Kokalis-burelle, N.; Martinez-ochoa, N.; Rodri?guez-ka?bana, R.; Kloepper, J. W.

2002-01-01

62

Evaluation of repeated bio disinfestation using Brassica carinata pellets to control Meloidogyne incognita in protected pepper crops  

Energy Technology Data Exchange (ETDEWEB)

The nematode Meloidogyne incognita is responsible for substantial losses in greenhouse-grown peppers in southeastern Spain. This study evaluates the use of biodisinfestation (BS) (organic amendment + solarisation) as an alternative to using methyl bromide (MB) over three consecutive years to control the nematode in greenhouse conditions. Brassica carinata (BP) pellets or B. carinata (BP) + fresh sheep manure (M) were evaluated in treatments which began on two different dates (August and October) and the results were compared with MB-disinfested and untreated controls. During the third year, the gall index for BP was lower than that obtained for BP +M and in the August treatment than in the October treatment. The commercial crop of pepper fruit obtained with the biodisinfestation treatments begun in August was similar to or higher than that obtained with MB, and higher than that obtained with both October biodisinfestation treatments. The yield of the October biodisinfestation treatments was higher than that of the untreated one. In August of all the years studied, the accumulated exposure times were greater than the thresholds required to kill M. incognita populations at 15 cm depth. The incidence of the nematode did not correspond to the reduction achieved during solarisation, and seemed to increase during the crop cycle. Further studies should look at why high temperatures do not produce a sustained reduction in the populations of Meloidogyne incognita. (Author) 56 refs.

Guerrero-Diaz, M. M.; Lacasa-Martinez, C. M.; Hernandez-Pinera, A.; Martinez-Alarcon, V.; Lacasa Plasencia, A.

2013-06-01

63

Susceptibility of Several Common Subtropical Weeds to Meloidogyne arenaria, M. incognita, and M. javanica.  

Science.gov (United States)

Experiments were conducted in the greenhouse to assess root galling and egg production of three root-knot nematode species, Meloidogyne arenaria, M. incognita, and M. javanica, on several weeds common to Florida agricultural land. Weeds evaluated were Amaranthus retroflexus (redroot pigweed), Cyperus esculentus (yellow nutsedge), Eleusine indica (goosegrass), Portulaca oleracea (common purslane), and Solanum americanum (American black nightshade). Additionally, although it is recommended as a cover crop in southern regions of the U.S., Aeschynomene americana (American jointvetch) was evaluated as a weed following the detection of root galling in a heavy volunteer infestation of an experimental field in southeastern Florida. Weeds were propagated from seed and inoculated with 1000 nematode eggs when plants reached the two true-leaf stage. Tomato (Solanum lycopersicum 'Rutgers') was included as a positive control. Aeschynomene americana and P. oleracea roots supported the highest number of juveniles (J2) and had the highest number of eggs/g of root for all three species of Meloidogyne tested. However, though P. oleracea supported very high root levels of the three nematode species tested, its fleshy roots did not exhibit severe gall symptoms. Low levels of apparent galling, combined with high egg production, increase the potential for P. oleracea to support populations of these three species of root-knot nematodes to a degree that may not be appropriately recognized. This research quantifies the impact of P. oleracea as a host for M. arenaria, M. incognita, and M. javanica compared to several other important weeds commonly found in Florida agricultural production, and the potential for A. americana to serve as an important weed host of the three species of root-knot nematode tested in southern regions of Florida. PMID:23482324

Kokalis-Burelle, Nancy; Rosskopf, Erin N

2012-06-01

64

Raphanus sativus, Sinapis alba, and Fagopyrum esculentum as Hosts to Meloidogyne incognita, Meloidogyne javanica, and Plasmodiophora brassicae.  

Science.gov (United States)

Cultivars of oilseed radish (Raphanus sativus var. oleifera cv. Adagio, Nemex, Pegletta, Renova, Siletina, Siletta Nova, and Ultimo), white mustard (Sinapis alba cv. Albatross, Emergo, Maxi, Martigena, Metex, and Serval), buckwheat (Fagopyrum esculentum cv. Prego, Tardo), and phacelia (Phacelia tanacetifolia cv. Angelia) were tested for susceptibility to Meloidogyne incognita race 3 and Meloidogyne javanica. Experiments were conducted in growth chambers at 25 C and 16 hours light for 42 days after inoculation with second-stage juveniles (J2). All cultivars were susceptible to M. incognita and M. javanica. The oilseed radish (cv. Nemex, Pegletta, and Renova) and white mustard (cv. Emergo) were also examined to determine the influence of Heterodera schachtii on susceptibility to Plasmodiophora brassicae as measured by incidence and severity of root galling. All cultivars were susceptible, and neither the severity nor incidence of clubroot galling was affected by H. schachtii. PMID:19279960

Gardner, J; Caswell-Chen, E P

1994-12-01

65

Produtos naturais aplicados para manejo de Meloidogyne incognita em tomateiros / Natural products applied to the management of Meloidogyne incognita in tomato plants  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Este trabalho teve por objetivo avaliar o efeito de produtos naturais na expressão da resistência a Meloidogyne incognita em plantas de tomate produzidos organicamente. Os indutores Rocksil, Quitosana, Neemseto e Biopirol foram aplicados 5, 10 e 15 dias, em tratamentos independentes, antes da inocul [...] ação do patógeno através da pulverização foliar, utilizando-se duas dosagens para cada indutor. A inoculação do nematoide foi realizada 30 dias após o plantio, usando-se 5000 ovos/ planta. Avaliando-se o número de ovos e o fator de reprodução, 30 dias após a inoculação, observou-se que todos os tratamentos diferiram estatisticamente da testemunha, impedindo o aumento da população inicial do patógeno. Dentre os indutores, o indutor silicatado Rocksil foi o que apresentou os melhores resultados para o controle da meloidoginose em todas as épocas de aplicação e em todas as dosagens. Contudo, plantas tratadas com o produto apresentaram baixos pesos de parte aérea sugerindo que houve um custo adaptativo de resistência. Considerando-se o fator de reprodução não foram observadas diferenças estatísticas quando comparadas a dosagem e época de aplicação entre os indutores, com exceção da Quitosana aplicada aos 5 dias antes da inoculação e do Neemseto aplicado aos 15 dias antes da inoculação do nematóide. Abstract in english This study aimed to evaluate the effect of natural products on the expression of resistance to Meloidogyne incognita in organically produced tomato plants. The inducers Rocksil, Chitosan, Neemseto and Biopirol were applied at 5, 10 and 15 days as independent treatments before the pathogen inoculatio [...] n by means of leaf spraying, using two levels for each inducer. The nematode inoculation was performed at 30 days after planting, using 5000 eggs/plant. Evaluating the number of eggs and the reproduction factor, at 30 days after inoculation, all treatments statistically differed from the control, preventing an increase in the initial population of the pathogen. Of the natural inducers, Rocksil showed the best results for controlling the root-knot nematode in all application times and at all levels. However, plants treated with the product had low shoot weights, suggesting that there was a fitness cost of resistance. Considering the reproduction factor, there were not statistical differences when the level and the application time were compared among natural inducers, except for Chitosan applied at 5 days before the nematode inoculation and Neemseto applied at 15 days before the nematode inoculation.

Thiago Anchieta de, Melo; Ilka Márcia Ribeiro de Sousa, Serra; Gilson Soares da, Silva; Rosa Maria Souto de, Sousa.

2012-09-01

66

Nematicidal effects of Leucaena leucocephala and Gliricidia sepium extracts on Meloidogyne incognita infecting okra  

Directory of Open Access Journals (Sweden)

Full Text Available Two separate but identical greenhouse trials were conducted to investigate the effects of extracts of leaves and roots of Leucaena leucocephala and Gliricidia sepium each at 80,000 mg / kg and 40,000 mg / kg on Meloidogyne incognita on okra. Each potted nine-day old okra seedling was inoculated with 3,000 fresh eggs of M. incognita and 5ml of each of the extracts was added simultaneously around the roots of the seedling. Treatment of okra plant with L. leucocephala and G. sepium extracts resulted in reduced nematode population, reduced galling, reduced nematode reproduction rate and enhanced fruit weight. Chemical analysis revealed that G. sepium leaves contained phenolic compound and carboxylic acid, while the roots showed the presence of aromatic amide, phenolic compound and carboxylic acid. L. leucocephala leaves showed the presence of phenolic compound, aromatic amide and carboxylic acid, while the roots showed the presence of phenolic compound and carboxylic acid. The results of this study suggest that leaf and root extracts of L. leucocephala and G. sepium at the rate of 40,000 mg / kg could be useful in root knot nematode management in vegetable beds.

Adekunle O.K.

2007-01-01

67

Production of auxin and related compounds by the plant parasitic nematodes Heterodera schachtii and Meloidogyne incognita.  

Science.gov (United States)

Mass spectrometric analysis revealed the presence of auxin, mainly in conjugated form, in secretions of Heterodera schachtii and Meloidogyne incognita, with or without treatment with DMT or resorcinol. M. incognita showed the highest production rates, though treatment of M. incognita with resorcinol had a negative effect on auxin production. Analysis of auxin precursor molecules in lysates of H. schachtii, M. incognita and Caenorhabditis elegans suggested that auxin is most probably a degradation product of tryptophan and that auxin may be synthesized via several intermediates, including indole-3-acetamide which is an intermediate of a pathway so far only characterized in bacteria. Furthermore, high levels of anthranilate, a degradation product of tryptophan in animals, but possibly also a precursor for auxin were detected. PMID:16363359

De Meutter, J; Tytgat, T; Prinsen, E; Gheysen, G; Van Onckelen, H; Gheysen, G

2005-01-01

68

HISTOPATHOLOGICAL CHANGES AND ENZYMATIC ACTIVITIES INDUCED BY MELOIDOGYNE INCOGNITA ON RESISTANT AND SUSCEPTIBLE POTATO  

Directory of Open Access Journals (Sweden)

Full Text Available All potato cultivars are susceptible to root-knot nematodes (Meloidogyne spp. which infest the roots and induce galls on the surface and necrotic spots in the flesh tuber of potato, Solanum tuberosum. Infested tubers are unacceptable for processing and fresh market. Tubers are also putative source of dissemination of the nematode. A French nematode- resistant tetraploid potato genotype gained from ex-S. sparsipilum material hybridized with S. tuberosum in F1 and in their back cross progenies and designated as 02T.155.6 was tested and compared in the present study in Egypt as a suitable different environment. Histopathological changes and chitinase activity induced by M. incognita population, of common occurrence in Egypt, in four French tetraploid materials and two common cultivars known as nematode- resistant and susceptible potato genotypes were investigated. Hypertrophied cells were initiated in both cortical and steler regions of the roots which were then developed to abnormal xylem elements expanding into the cortex in French susceptible genotypes designated as 02T.149.6, 02T.150.54, and 02T.157.16. Nematode within the vascular tissue (stele could induce giant cell development close to nematode heads. The largest number of such induced cells was shown by the cultivars Spunta and Diamant. The clone 02T.155.6 with putative nematode resistance demonstrated none or very little nematode development. Recently dead second stage juveniles could also indicate incompatible plant reaction to the invading nematodes in 02T.155.6. M. incognita, Giza population, resistance was generally more coherent to 02T.155.6 as demonstrated by our histological investigations but less coherent as shown by another Egyptian M. incognita population. Chitinase activity was enhanced in M. incognita (Giza-inoculated with respect to uninoculated roots in all plants. After inoculation, such an activity generally increased more in roots of a potato genotype previously known to have resistance or relatively low numbers of both nematode galls and eggmasses than in the other tested cultivars. Peroxidase and catalase activities of nematode- inoculated with respect to uninoculated potato roots were presented and discussed.

Moawad M. Mohamad

2012-12-01

69

Systemic nematicidal activity and biocontrol efficacy of Bacillus firmus against the root-knot nematode Meloidogyne incognita.  

Science.gov (United States)

A strain of marine bacterium Bacillus firmus YBf-10 with nematicidal activity was originally isolated by our group. In the present study, the systemic nematicidal activity and biocontrol efficacy in pot experiment of B. firmus YBf-10 were investigated. Our results showed that YBf-10 exhibits systemic nematicidal activity against Meloidogyne incognita, including lethal activity, inhibition of egg hatch and motility. Pot experiment suggested that soil drenching with YBf-10 efficiently reduced damage of M. incognita to tomato plants, such as reduction of galls, egg masses on roots, and final nematode population in soil; and moreover, YBf-10 significantly promoted host plant growth. In addition, our results also indicated that the systemic nematicidal activity is likely attributed to the secondary metabolites produced by YBf-10. The obtained results of the current study confirmed that B. firmus YBf-10 is a promising nematicidal agent, and has great potential in plant-parasitic nematicidal management. PMID:25672545

Xiong, Jing; Zhou, Qiaoni; Luo, Haiyan; Xia, Liqiu; Li, Lin; Sun, Ming; Yu, Ziquan

2015-04-01

70

Synergistic activity between Bacillus thuringiensis Cry6Aa and Cry55Aa toxins against Meloidogyne incognita  

OpenAIRE

Plant?parasitic nematodes are the most destructive group of plant pathogens worldwide and are extremely challenging to control. Some Bacillus thuringiensis crystal proteins are highly toxic to the plant?parasitic nematode Meloidogyne incognita. In this study, the nematicidal crystal proteins Cry6Aa, Cry5Ba and Cry55Aa were tested against M.?incognita to select the best toxin combination for its management. The results showed that a combination of Cry6Aa and Cry55Aa showed significant sy...

Peng, Donghai; Chai, Lujun; Wang, Fenshan; Zhang, Fengjuan; Ruan, Lifang; Sun, Ming

2011-01-01

71

Growth and Energy Demand of Meloidogyne incognita on Susceptible and Resistant Vitis vinifera Cultivars  

OpenAIRE

Food (energy) consumption rates ofMeloidogyne incognita were calculated on Vitis vinifera cv. French Colombard (highly susceptible) and cv. Thompson Seedless (moderately resistant). One-month-old grape seedlings in styrofoam cups were inoculated with 2,000 or 8,000 M. incognita second-stage juveniles (J2) and maintained at 17.5 degree days (DD - base 10 C)/day until maximum adult female growth and (or) the end of oviposition. At 70 DD intervals, nematode fresh biomass was calculated on the ba...

Melakeberhan, H.; Ferris, H.

1988-01-01

72

Effects of Management Practices on Meloidogyne incognita and Snap Bean Yield  

OpenAIRE

Phenamiphos applied at 6.7 kg ai/ha through a solid set or a center pivot irrigation system with 28 mm of water effectively controlled root-knot nematodes, Meloidogyne incognita, and resulted in greater snap bean growth and yields irrespective of growing season, tillage method, or cover crop system. The percentage yield increases attributed to this method of M. incognita control over nontreated controls were 45% in the spring crop, and 90% and 409% in the fall crops following winter rye and f...

Smittle, D. A.; Johnson, A. W.

1982-01-01

73

INDUCCIÓN DE ENZIMAS EXTRACELULARES CON HUEVOS DE Meloidogyne incognita Y DE Globodera pallida / INDUCTION OF EXTRACELLULAR ENZYMES WITH Meloidogyne incognita AND Globodera pallida EGGS  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish La cepa cubana IMI SD 187 del hongo nematofago Pochonia chlamydosporia var. catenulata es un agente de control biológico potencial de nematodos formadores de agallas. Existen informes sobre la acción controladora de los hongos de la especie Pochonia chlamydosporia sobre nematodos de quistes. Sin emb [...] argo también se conoce de la especificidad de los aislamientos según su hospedante original. El objetivo de este trabajo fue estudiar el comportamiento de diferentes sistemas enzimáticos en la cepa IMI SD 187, frente a huevos de Meloidogyne incognita y Globodera pallida. Se realizaron los ensayos de inducción con huevos de ambos nematodos en medio líquido y se determinaron los contenidos de proteínas totales y niveles de actividad enzimática de proteasas, quitinasas, lipasas y VCP 1. La dinámica de la inducción de los sistemas enzimáticos estuvo relacionada con las fases del proceso de infección de los huevos de M. incognita en la cepa IMI SD 187. Esta cepa de P. chlamydosporia var. catenulata procedente de nematodos formadores de agallas es capaz de infectar huevos de nematodos de quistes. Abstract in english The Cuban strain IMI SD 187 of the nematophagous fungus Pochonia chlamydosporia var. catenulata is a potential biological control agent for the root knot nematodes. There are reports about the controlling action of these fungi on cyst nematodes. However, isolate specificity according to the original [...] host is also known. The aim of this work was to study the enzymatic performance induced by Meloidogyne incognita and Globodera pallida eggs. The induction assays were carried out in liquid media. The total protein content and the enzymatic activity levels for proteases, chitinases, lipases and VCP 1 were determined. The time course experiment for enzymatic activity induction was related to the infection process of M. incognita eggs by the strain IMI SD 187. The strain IMI SD 187 of P. chlamydosporia var. catenulata isolated from root knot nematodes is able to infect eggs from cyst nematodes.

Belkis, Peteira; Ivania, Estévez; S, Atkins; L, Hidalgo-Díaz; B, Kerry.

2009-08-01

74

Identification of cytokinins produced by the plant parasitic nematodes Heterodera schachtii and Meloidogyne incognita.  

Science.gov (United States)

SUMMARY The presence of different types of cytokinins was analysed in exudates and lysates of stage-2 juveniles of Heterodera schachtii and Meloidogyne incognita and in mixed stages of Caenorhabditis elegans. For all species, cytokinins were detected in lysates and exudates in which benzyladenine and zeatin-type cytokinins were the most prominent forms. The production of cytokinins by Meloidogyne was much higher than by Heterodera, and the detected levels were in a range which interfered with the physiological activities of the host plant. The presence of 5-methoxy-N,N-dimethyltryptamine hydrogen oxalate did not affect hormone production by H. schachtii, whereas resorcinol slightly stimulated hormone production by M. incognita. The exuded cytokinins may play a role in feeding site induction, more particularly in cell cycle activation and in establishing the feeding site as a nutrient sink. PMID:20569387

De Meutter, Jan; Tytgat, Tom; Witters, Erwin; Gheysen, Greetje; Van Onckelen, Henri; Gheysen, Godelieve

2003-07-01

75

Evidence Against Amplification of Four Genes in Giant Cells Induced by Meloidogyne incognita  

OpenAIRE

Giant-cell DNA was isolated from pea (Pisum sativum) inoculated with Meloidogyne incognita and used in slot blots to test for selective sequence amplification. Four sequences representing low (ribulose 1,5-bisphosphate carboxylase and actin), mid-level (histone 3), and highly repetitive (large ribosomal repeat) sequence DNA were used as probes. Known amounts of root-tip DNA and giant-cell DNA were blotted onto hybridization membranes and probed. The signal strength on autoradiographs containi...

Wiggers, R. J.; Magill, C. W.; Starr, J. L.; Price, H. J.

1991-01-01

76

Response of Sesamum indicum and S. radiatum Accessions to Root-knot Nematode, Meloidogyne incognita  

OpenAIRE

Twenty Sesame indicum and four S. radiatum accessions in the USDA Plant Introduction collection were evaluated for reaction to the root-knot nematode, Meloidogyne incognita race 3, at two initial egg densities under greenhouse conditions. All sesame accessions produced considerably fewer root galls than the tomato cultivar Rutgers. Gall numbers varied slightly among accessions at the higher infestation density with even less variation at the lower density. Egg mass indices indicated little re...

Walker, J. T.; Melin, J. B.; Davis, J.

1998-01-01

77

Interaction between Meloidogyne incognita and Agrobacterium tumefaciens or Fusarium oxysporum f. sp. lycopersici on Tomato  

OpenAIRE

Agrobacterium tumefaciens stimulated and Fusarium oxysporum f. sp. lycopersici inhibited development and reproduction of Meloidogyne incognita when applied to the opposite split root of tomato, Lycopersicon esculentum cv. Tropic, plants. The lowest rate of nematode reproduction occurred after 2,000 juveniles were applied and the fungus was present in the opposite split root. The effects of all three pathogens alone on the growth of roots and shoots of tomato plants were evident, but M. incogn...

El-sherif, Ahmed G.; Elwakil, M. A.

1991-01-01

78

EFFECT OF ROOT EXUDATES OF TAGETES SP. ON EGG HATCHING BEHAVIOR OF MELOIDOGYNE INCOGNITA  

OpenAIRE

The effect root exudates of pre-planted marigold intercropped with tomato in regulating the hatching behavior of root-knot nematode - Meloidogyne incognita eggs were investigated. Marigold cultivars Tagetes patula, T. minuta, T. erecta, T. erecta (var. Orange), T. erecta (var. Yellow) significantly reduced the numbers of second-stage juveniles (J2s) in subsequent tomato compared to the tomato-tomato control. Four different concentrations (25, 50, 75 and 100 %) of water soluble extract from th...

Iruthaya Kalaiselvam; Aruna Devaraj

2011-01-01

79

Chemical Composition and Nematicidal Activity of Essential Oil of Agastache rugosa against Meloidogyne incognita  

OpenAIRE

The aim of this research was to determine the chemical composition and nematicidal activity of essential oil of Agastache rugosa flowering aerial parts against the root knot nematode, Meloidogyne incognita, and to isolate and identify any nematicidal constituents from the essential oil. The essential oil of A. rugosa aerial parts was obtained by hydrodistillation and analyzed by GC-FID and GC-MS. A total of 37 components of the essential oil were identified, with the principal compounds being...

Zhi Wei Deng; Shu Shan Du; Zhi Long Liu; Qi Zhi Liu; He Qin Li

2013-01-01

80

Nematicidal activity of plant extracts against the root-knot nematode, Meloidogyne incognita  

OpenAIRE

Nematicidal activity of extracts from plants was assayed against Meloidogyne incognita. In laboratory assays extracts from tobacco (Nicotiana tabacum L), clove (Syzygium aromaticum L), betelvine (Piper betle L), and sweet flag (Acorus calamus L) were most effective in killing the nematode, with an EC50 that was 5-10 times lower than the EC50 of the synthetic pesticides chlorpyrifos, carbosulfan and deltamethrin. The shapes of the dead nematodes differed in a characteristic way, and groups of ...

Wiratno; Taniwiryono, D.; Berg, J. H. J.; Riksen, J. A. G.; Rietjens, I.; Djiwanti, S. R.; Kammenga, J. E.; Murk, A. J.

2009-01-01

81

Efficacy of a Novel Nematicidal Seed Treatment against Meloidogyne incognita on Cotton  

OpenAIRE

The efficacy of abamectin as a seed treatment for control of Meloidogyne incognita on cotton was evaluated in greenhouse, microplot, and field trials in 2002 and 2003. Treatments ranging from 0 to 100 g abamectin/100 kg seed were evaluated. In greenhouse tests 35 d after planting (DAP), plants from seed treated with abamectin were taller than plants from nontreated seed, and root galling severity and nematode reproduction were lower where treated seed were used. The number of second stage juv...

Monfort, W. S.; Kirkpatrick, T. L.; Long, D. L.; Rideout, S.

2006-01-01

82

The nematicidal effect of some bacterial biofertilizers on Meloidogyne incognita in sandy soil  

OpenAIRE

In a greenhouse experiment, the nematicidal effect of some bacterial biofertilizers including the nitrogen fixing bacteria (NFB) Paenibacillus polymyxa (four strains), the phosphate solubilizing bacteria (PSB) Bacillus megaterium (three strains) and the potassium solubilizing bacteria (KSB) B. circulans (three strains) were evaluated individually on tomato plants infested with the root-knot nematode Meloidogyne incognita in potted sandy soil. Comparing with the uninoculated nematode-infested ...

El-hadad, M. E.; Mustafa, M. I.; Selim, Sh M.; El-tayeb, T. S.; Mahgoob, A. E. A.; Abdel Aziz, Norhan H.

2011-01-01

83

Survival of Paecilomyces lilacinus in Selected Carriers and Related Effects on Meloidogyne incognita on Tomato  

OpenAIRE

Laboratory and microplot experiments were conducted to determine the influence of carrier and storage of Paecilomyces lilacinus on its survival and related protection of tomato against Meloidogyne incognita. Spores of P. lilacinus were prepared in five formulations: alginate pellets (pellets), diatomaceous earth granules (granules), wheat grain, soil, and soil plus chitin. Fungal viability was high in wheat and granules, intermediate in pellets, and low in soil and chitin-amended soil stored ...

Cabanillas, Enrique; Barker, K. R.; Nelson, L. A.

1989-01-01

84

Identification of the Chromosome Carrying the Factor for Resistance to Meloidogyne incognita in Tobacco  

OpenAIRE

To identify the chromosome carrying the factor for resistance to Meloidogyne incognita in tobacco, crosses were made between resistant tobacco 'NC95' as pollen parent and each of the 12 tobacco monosomics (A-L) representative of the Tomentosae half of the Nicotiana tabacum chromosome complement. Of the F? seedlings, 927 plants were grown for observation. From these, 223 plants were selected as possible monosomics on the basis of morphological characteristics. These plants were self-pollinat...

Slana, L. J.; Stavely, J. R.

1981-01-01

85

Meloidogyne incognita and M. arenaria Reproduction on Dwarf Hollies and Lantana  

OpenAIRE

Meloidogyne incognita and M. arenaria reproduction and host plant tolerance were assessed in field and greenhouse experiments on seven holly cultivars including Ilex glabra 'Shamrock', I. vomitoria 'Schelling's Dwarf', I. cornuta 'Carissa', red holly hybrid (Ilex Little Red™), and I. crenata 'Compacta', 'Green Luster', and 'Helleri' as well as Japanese boxwood (Buxus microphylla) and two lantana cultivars (Lantana camara 'Miss Huff' and 'New Gold'). Boxwood had the highest M. arenaria and M...

Williams-woodward, J. L.; Davis, R. F.

2001-01-01

86

Stage-specific Differences in Lectin Binding to the Surface of Anguina tritici and Meloidogyne incognita  

OpenAIRE

The occurrence and distribution of several lectin binding sites on the outer surfaces of eggs, preparasitic second-stage juveniles (J2), parasitic second-stage juveniles (PJ2), females, and males of two tylenchid nematodes, Anguina tritici and Meloidogyne incognita race 3, were compared. In both species, a greater variety of lectins bound to the eggs than to other life stages; lectin binding to eggs was also more intense than it was to other life stages. Species-specific differences also occu...

Spiegel, Yitzhak; Mcclure, Michael A.

1991-01-01

87

Expression of Resistance to Meloidogyne incognita in Kenaf Cultivars (Hibiscus cannibinus) under Field Conditions  

OpenAIRE

Field studies were conducted in 2003 and 2004 to investigate the reaction of 10 varieties of kenaf to natural infestation of Meloidogyne incognita. Ten weeks after planting, ten randomly selected plants per variety were assessed for root galling. Plants were carefully uprooted soil adhering to roots was washed off under a gentle stream of tap water and roots then were observed using a stereo microscope. Eggs were extracted from the roots with sodium hypochlorite. The reproduction factor (Pf /...

Adegbite, A. A.; Agbaje, G. O.; Akande, M. O.; Amusa, N. A.; Adetumbi, J. A.; Adeyeye, O. O.

2005-01-01

88

Induction of Isoperoxidases in Resistant and Susceptible Tomato Cultivars by Meloidogyne incognita  

OpenAIRE

Isoperoxidases were detected in resistant Rossol and susceptible Roma VF tomato roots uninfected and infected by Meloidogyne incognita. Syringaldazine, guaiacol, p-phenylenediamine-pyrocatechol (PPD-PC), and indoleacetic acid (IAA) were used as substrates, and the corresponding peroxidative activities were detected either in cytoplasmic or in cell wall fractions, except for IAA oxidase, which was measured in soluble and microsomal fractions. Isoperoxidase activities and cellular locations wer...

Molinari, Sergio

1991-01-01

89

Chloroplast Differentiation in Tomato Root Galls Induced by the Root Knot Nematode Meloidogyne incognita  

OpenAIRE

Primary roots of tomato, Lycopersicon esculentum cv. Marglobe, were cultured aseptically on agar containing a standard nutrient formulation with or without kinetin. When secondary roots developed, cultures were inoculated with the root-knot nematode, Meloidogyne incognita. Following inoculation, the cultures were divided into two groups which were incubated either in total darkness or in 16-h light-8-h dark cycles. At 24 h, 1, 2, 3, and 4 wk after incubation, roots from all cultures were proc...

Orion, D.; Wergin, W. P.

1982-01-01

90

Direct Identification of the Meloidogyne incognita Secretome Reveals Proteins with Host Cell Reprogramming Potential  

OpenAIRE

The root knot nematode, Meloidogyne incognita, is an obligate parasite that causes significant damage to a broad range of host plants. Infection is associated with secretion of proteins surrounded by proliferating cells. Many parasites are known to secrete effectors that interfere with plant innate immunity, enabling infection to occur; they can also release pathogen-associated molecular patterns (PAMPs, e.g., flagellin) that trigger basal immunity through the nematode stylet into the plant c...

Bellafiore, Ste?phane; Shen, Zhouxin; Rosso, Marie-noelle; Abad, Pierre; Shih, Patrick; Briggs, Steven P.

2008-01-01

91

Plantago lanceolata and Plantago rugelii Extracts are Toxic to Meloidogyne incognita but not to Certain Microbes  

OpenAIRE

Extracts from the plants Plantago lanceolata and P. rugelii were evaluated for toxicity to the root-knot nematode Meloidogyne incognita, the beneficial microbes Enterobacter cloacae, Pseudomonas fluorescens and Trichoderma virens, and the plant-pathogenic fungi Fusarium oxysporum f. sp. gladioli, Phytophthora capsici, Pythium ultimum, and Rhizoctonia solani. Wild plants were collected, roots were excised from shoots, and the plant parts were dried and ground to a powder. One set of extracts (...

Meyer, Susan L. F.; Zasada, Inga A.; Roberts, Daniel P.; Vinyard, Bryan T.; Lakshman, Dilip K.; Lee, Jae-kook; Chitwood, David J.; Carta, Lynn K.

2006-01-01

92

Mustard seed meal mixtures: management of Meloidogyne incognita on pepper and potential phytotoxicity  

OpenAIRE

Meals produced when oil is extracted from seeds in the Brassicaceae have been shown to suppress weeds and soilborne pathogens. These seed meals are commonly used individually as soil amendments; the goal of this research was to evaluate seed meal mixes of Brassica juncea (Bj) and Sinapis alba (Sa) against Meloidogyne incognita. Seed meals from Bj ‘Pacific Gold’ and Sa ‘IdaGold’ were tested alone and in combinations to determine rates and application times that would suppress M. incogn...

Meyer, Susan L. F.; Zasada, Inga A.; Orisajo, Samuel B.; Morra, Matthew J.

2011-01-01

93

EFFECT OF ROOT EXUDATES OF TAGETES SP. ON EGG HATCHING BEHAVIOR OF MELOIDOGYNE INCOGNITA  

Directory of Open Access Journals (Sweden)

Full Text Available The effect root exudates of pre-planted marigold intercropped with tomato in regulating the hatching behavior of root-knot nematode - Meloidogyne incognita eggs were investigated. Marigold cultivars Tagetes patula, T. minuta, T. erecta, T. erecta (var. Orange, T. erecta (var. Yellow significantly reduced the numbers of second-stage juveniles (J2s in subsequent tomato compared to the tomato-tomato control. Four different concentrations (25, 50, 75 and 100 % of water soluble extract from the selected varieties of Marigold cultivars were filtered and added to the petri dish and infested with the eggs of M. incognita. Data indicate that egg hatching was significantly affected by root exudates of Tagetes sp. however, nematicidal activity was species dependent. Root exudates of T. erecta were lethal to J2 of M. incognita and were inhibitory to the hatch of eggs at the concentration of 75 % or higher.

Iruthaya Kalaiselvam

2011-10-01

94

Effects of Meloidogyne incognita on Growth and Storage-Root Formation of Cassava (Manihot esculenta)  

Science.gov (United States)

Two-node cuttings of cassava cultivar SS4 were inoculated with 1,000 infective juveniles of Meloidogyne incognita at 1, 14, 40, 70, 88, and 127 days after planting (DAP). Plant growth and root damage were assessed at 150 DAP. Meloidogyne incognita significantly reduced the number of storageroots formed in plants inoculated at 14, 40, 70, and 88 DAP and the total weight of storage-roots in plants inoculated at 1, 14, 40, 70, and 88 DAP, compared to uninoculated plants. Individual storage-root weight and plant height were not affected by M. incognita. Storage-root formation in cassava is initiated when plants are 1 to 2 months old. The results of this experiment indicate that, at this time, young cassava plants are most prone to root-knot nematode damage in terms of storage-root formation. The production loss caused by M. incognita to young SS4 plants was due to a reduction of storage-root number rather than a reduction in individual storage-root weight. PMID:19270997

Makumbi-Kidza, N. N.; Speijer, P. R.; Sikora, R. A.

2000-01-01

95

The nematicidal effect of some bacterial biofertilizers on Meloidogyne incognita in sandy soil  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english In a greenhouse experiment, the nematicidal effect of some bacterial biofertilizers including the nitrogen fixing bacteria (NFB) Paenibacillus polymyxa (four strains), the phosphate solubilizing bacteria (PSB) Bacillus megaterium (three strains) and the potassium solubilizing bacteria (KSB) B. circu [...] lans (three strains) were evaluated individually on tomato plants infested with the root-knot nematode Meloidogyne incognita in potted sandy soil. Comparing with the uninoculated nematode-infested control, the inoculation with P. polymyxa NFB7, B. megaterium PSB2 and B. circulans KSB2, increased the counts of total bacteria and total bacterial spores in plants potted soil from 1.2 to 2.6 folds estimated 60 days post-inoculation. Consequently, the inoculation with P. polymyxa NFB7 increased significantly the shoot length (cm), number of leaves / plant, shoot dry weight (g) / plant and root dry weight (g) / plant by 32.6 %, 30.8 %, 70.3 % and 14.2 %, respectively. Generally, the majority treatments significantly reduced the nematode multiplication which was more obvious after 60 days of inoculation. Among the applied strains, P. polymyxa NFB7, B. megaterium PSB2 and B. circulans KSB2 inoculations resulted in the highest reduction in nematode population comparing with the uninoculated nematode-infested control. They recorded the highest reduction in numbers of hatched juveniles/root by 95.8 %, females/root by 63.75 % and juveniles/1kg soil by 57.8 %. These results indicated that these bacterial biofertilizers are promising double purpose microorganisms for mobilizing of soil nutrients (nitrogen, phosphate and potassium) and for the biological control of M. incognita.

M.E, El-Hadad; M.I, Mustafa; Sh.M, Selim; T.S, El-Tayeb; A.E.A, Mahgoob; Norhan H. Abdel, Aziz.

2011-03-01

96

The nematicidal effect of some bacterial biofertilizers on Meloidogyne incognita in sandy soil  

Directory of Open Access Journals (Sweden)

Full Text Available In a greenhouse experiment, the nematicidal effect of some bacterial biofertilizers including the nitrogen fixing bacteria (NFB Paenibacillus polymyxa (four strains, the phosphate solubilizing bacteria (PSB Bacillus megaterium (three strains and the potassium solubilizing bacteria (KSB B. circulans (three strains were evaluated individually on tomato plants infested with the root-knot nematode Meloidogyne incognita in potted sandy soil. Comparing with the uninoculated nematode-infested control, the inoculation with P. polymyxa NFB7, B. megaterium PSB2 and B. circulans KSB2, increased the counts of total bacteria and total bacterial spores in plants potted soil from 1.2 to 2.6 folds estimated 60 days post-inoculation. Consequently, the inoculation with P. polymyxa NFB7 increased significantly the shoot length (cm, number of leaves / plant, shoot dry weight (g / plant and root dry weight (g / plant by 32.6 %, 30.8 %, 70.3 % and 14.2 %, respectively. Generally, the majority treatments significantly reduced the nematode multiplication which was more obvious after 60 days of inoculation. Among the applied strains, P. polymyxa NFB7, B. megaterium PSB2 and B. circulans KSB2 inoculations resulted in the highest reduction in nematode population comparing with the uninoculated nematode-infested control. They recorded the highest reduction in numbers of hatched juveniles/root by 95.8 %, females/root by 63.75 % and juveniles/1kg soil by 57.8 %. These results indicated that these bacterial biofertilizers are promising double purpose microorganisms for mobilizing of soil nutrients (nitrogen, phosphate and potassium and for the biological control of M. incognita.

M.E El-Hadad

2011-03-01

97

Rootstocks resistant to Meloidogyne incognita and compatibility of grafting in net melon / Porta-enxertos resistentes a Meloidogyne incognita e compatibilidade de enxertia de melão rendilhado  

Scientific Electronic Library Online (English)

Full Text Available Devido aos poucos estudos realizados com enxertias em melão rendilhado, visando um maior controle de patógenos do solo, este trabalho teve por objetivo avaliar 16 genótipos de cucurbitáceas quanto à resistência a Meloidogyne incognita e a compatibilidade da enxertia do melão rendilhado. Foram avalia [...] dos 16 acessos de cucurbitáceas: Benincasa hispida, Bucha, Abóbora 'Jacarezinho', Abóbora 'Menina Brasileira', Moranga 'Exposição', Moranga 'Coroa', Abóbora 'Canhão Seca', Abóbora 'Squash', Mogango 'Enrrugado Verde', Abóbora 'Mini Paulista', Abóbora 'Goianinha', Melancia 'Charleston Gray', Melão 'Rendondo Gaúcho', Melão 'Redondo Amarelo', Pepino 'Caipira HS' e Pepino 'Caipira Rubi', quanto à resistência ao nematóide M. incognita, com base no fator de reprodução (FR), segundo Oostenbrink (1966). Para avaliação da resistência, as mudas foram transplantadas para vasos de cerâmica e foram aplicados 300 ovos ou juvenis de segundo estádio/mL de M. incognita, num total de 10 mL por vaso. Aos 50 dias após o transplantio, as plantas foram removidas dos vasos e realizou-se a avaliação da resistência. Para a compatibilidade entre os porta-enxertos resistentes e enxerto de melão rendilhado, foram realizadas enxertias do tipo garfagem fenda simples, em híbrido comercial de melão rendilhado de grande aceitação comercial e suscetíveil a M. incognita (Bônus N° 2). Os genótipos Bucha, Abóbora 'Goianinha', Abóbora 'Mini-Paulista', Melão 'Redondo Amarelo', Melancia 'Charleston Gray', foram resistentes ao nematóide M. incognita. As melhores compatibilidades ocorreram com os porta-enxertos Melão 'Amarelo', o qual teve 100% de pegamento, seguido da Abóbora 'Mini-Paulista' com 94%. Já Bucha, Melancia 'Charleston Gray' e Abóbora 'Goianinha', tiveram baixas porcentagens de pegamento: 66%, 62% e 50% respectivamente. Abstract in english Due to the few studies about grafting in net melon, in order to obtain better control of soil pathogens, the aim of the present study was to evaluate 16 genotypes of Cucurbitaceae: Benincasa hispida, Luffa cylindrica, pumpkin 'Jacarezinho', pumpkin 'Menina Brasileira', squash 'Exposição', squash 'Co [...] roa', pumpkin 'Canhão Seca', pumpkin 'Squash', pumpkin 'Enrrugado Verde', pumpkin 'Mini Paulista', pumpkin 'Goianinha', watermelon 'Charleston Gray', melon 'Rendondo Gaucho', melon 'Redondo Amarelo', cucumber 'Caipira HS' and cucumber 'Caipira Rubi', regarding to compatibility of grafting in net melon and resistance to Meloidogyne incognita, based on the reproduction factor (RF), according to Oostenbrink (1966). To assess resistance, the seedlings were transplanted to ceramic pots and inoculated with 300/mL eggs and/or second stage juveniles of M. incognita. At 50 days after transplanting, the plants were removed from the pots and the resistance was evaluated. The compatibility between resistant rootstock and grafts of net melon was determined by performing simple cleft grafting, in a commercial net melon hybrid of great market acceptance and susceptible to M. incognita (Bonus no. 2). The genotypes Luffa cylindrica, pumpkin 'Goianinha', pumpkin 'Mini-Paulista', melon 'Redondo Amarelo', watermelon 'Charleston Gray' are resistant to the nematode M. incognita. The better compatibilities occurred with the rootstocks melon 'Amarelo', which presented 100% of success, followed by pumpkin 'Mini-Paulista' with 94%. On the other hand, Sponge gourd, watermelon 'Charleston Gray' and pumpkin 'Goianinha' showed low graft take percentages of 66%, 62% and 50%, respectively.

Francine de Souza, Galatti; Alexandre Junqueira, Franco; Letícia Akemi, Ito; Hamilton de Oliveira, Charlo; Lucas Aparecido, Gaion; Leila Trevisan, Braz.

2013-06-01

98

Potential antagonistic effects of nine natural fatty acids against Meloidogyne incognita.  

Science.gov (United States)

Fatty acids, the essential components of life, were widely present in various seed cakes, gutter oil, and other resources. The objective of this study was to evaluate the potential antagonistic effects of nine fatty acids (FAs) against Meloidogyne incognita (root-knot nematodes). The results showed that butyric, caprylic, capric, lauric, myristic, palmitic, and oleic acids significantly reduced M. incognita reproduction, whereas cucumber (Cucumus sativus) biomass was not adversely affected by the tested FAs and was even significantly increased in several fatty acids treatments. All nine tested fatty acids showed apparent inhibitory effects on egg hatching on day 21, especially capric acid with which the hatching rate was reduced to 15.8% as compared to that using sterile distilled water. Caproic, caprylic, capric, lauric, myristic, and palmitic acids caused significantly higher mortality of the second-stage juvenile of M. incognita than the other three FAs, and both caprylic and capric acids resulted in approximately 50% mortality (2000 ?mol/L) after a 24 h exposure. In conclusion, fatty acids showed the nematicidal effect differently, among which capric acid showed a strong nematicidal effect and might be a powerful active substance for integrated M. incognita management. Given the general nematicidal properties of FAs, farmers might utilize waste resources, such as oil seed cake, gutter oil, etc., containing various FAs or use pure FAs for effective M. incognita management. PMID:23121218

Zhang, Wei-pu; Ruan, Wei-bin; Deng, Yun-ying; Gao, Yu-bao

2012-11-21

99

Interactions between arbuscular mycorrhizal fungi and Meloidogyne incognita in the ornamental plant Impatiens balsamina  

Scientific Electronic Library Online (English)

Full Text Available Biocontrol traits of arbuscular mycorrhizal fungi (AMF), in terms of single and mixed species inoculum, against the root knot nematode Meloidogyne incongita in Impatiens balsamina L., were examined with and without mineral fertilization in a greenhouse pot experiment. At harvest, 60 days after sowin [...] g, general plant growth parameters and plant defense response in terms of antioxidant activity and content of phenolic compounds in roots and leaves were measured. Also AMF root colonization and abundance ofnematode root-knots were determined. Mineral fertilization increased all plant growth parameters measured, which coincided with an increased disease development caused by M. incognita. Inoculation with AMF mitigated the observed plant growth reduction caused by M.incognita, though, higher abundance of M. incognita root knots was found in mycorrhizal plants. Plant defense responses in terms of antioxidant activity and content of phenolic compounds did not seem to be linked to the observed biocontrol traits of AMF against M. incognita. However, roots inoculated with a consortium of AMF, which presented less nematode root knots than roots with the single species inoculum, had the highest level of phenolic compounds. The results from the present study suggest that AMF induce tolerance in I. balsamina against the root knot nematode M. incognita.

J, Banuelos; A, Alarcón; J, Larsen; S, Cruz-Sánchez; D, Trejo.

2014-03-01

100

Meloidogyne incognita Inoculum Source Affects Host Suitability and Growth of Yellow Nutsedge and Chile Pepper.  

Science.gov (United States)

Meloidogyne incognita (Mi) reproduction and host plant responses in chile pepper (Capsicum annuum) and yellow nutsedge (Cyperus esculentus = YNS) to three sources of inoculum obtained by rearing a single Mi population on chile, YNS, and tomato were evaluated in two factorial greenhouse experiments. The interactive effects of Mi inoculum source and crop-weed competition were determined. In the absence of YNS competition, chile growth was reduced less by Mi inoculum from chile than by inoculum from YNS or tomato. When YNS was present, chile root weight was not affected and shoot weight increased with Mi initial inoculation, regardless of inoculum source. Chile plants inoculated with Mi from tomato exhibited double the nematode reproduction observed with inoculum from chile or YNS. With chile present, Mi reproduction on YNS was nearly three times greater with inoculum from tomato, but reproduction was similar among inoculum sources when chile was absent. Reductions in YNS root mass due to competition from chile failed to reduce the total number of Mi eggs produced on YNS plants. Differences in total Mi reproduction among inoculum sources were not attributable to differences in root growth or plant competition. This study illustrates the influence of Mi-YNS interactions and previous hosts on severity of Mi infection. PMID:19274174

Thomas, S H; Schroeder, J; Kenney, M J; Murray, L W

1997-09-01

101

Uso de agentes microbianos e químico para o controle de Meloidogyne incognita em soja = Use of microbial and chemical agents to control Meloidogyne incognita in soybean  

Directory of Open Access Journals (Sweden)

Full Text Available Nematoides de galhas constituem importante grupo de patógenos da cultura da soja e o manejo integrado é uma das principais medidas de controle que visam à redução de perdas econômicas. Neste trabalho foi avaliada a eficácia dos fungos Paecilomyces lilacinus (Thom. Samsom e Pochonia chlamydosporia (Goddard Zare & Gams (sinonímia Verticillium chlamydosporium, de um produto comercial à base de Bacillus sp. (Nemix e do nematicida químico Aldicarb no controle de Meloidogyne incognita em soja, variedade M-SOY 6101. O experimento foi realizado em casa-de-vegetação no delineamento experimental de blocos casualizados com nove tratamentos (três produtos biológicos usados no tratamento de sementes com ou sem a aplicação em pós-emergência, Aldicarb aplicado apenas em pós-emergência e duastestemunhas e quatro repetições. Aldicarb reduziu o número de ovos e de juvenis do nematoide. P. lilacinus foi o mais atuante dos agentes biológicos, favorecendo a manutenção da quantidade de matéria seca da raiz de soja e reduzindo o número de ovos. O produto Nemix e P. chlamydosporia somente tiveram ação efetiva na redução do número de ovos do nematoide. Com base nos resultados, foi possível concluir que o agente químico e os agentes biológicos avaliados neste trabalho tiveram moderada atividade no controle de M. incognita em soja.Root-knot nematodes are considered significant pathogens of soybean crops. The objective of this work was to evaluate the efficacy of two fungi (Paecilomyces lilacinus (Thom. Samsom and Pochonia chlamydosporia (Goddard Zare & Gams (syn. Verticillium chlamydosporium, a commercial product based on Bacillus sp. and Aldicarb on the control of Meloidogyne incognita on soybean, cultivar M-SOY 6101. The experimental design was set as randomized blocks with four replications. Nine treatments were evaluated: three biological agents used for seed treatment with and without post-emergence application, Aldicarb on post-emergence only, and two controls. All treatments were inoculated with the nematode, except for a blank control where only water was applied. One control-only treated with the nematode was also included. Aldicarb could reduce the number of eggs and juveniles in the roots. P. lilacinus showed the bestperformance among the biological control agents, reducing the number of eggs and increasing dry root weight. Nemix, a Bacillus sp. based commercial product and P. chlamydosporia could only reduce significantly the number of eggs of the nematode. In this work, it was possible to conclude that the chemical and biological agents showed a moderate activity in the control of M. incognita in soybean.

Henrique Teixeira Nunes

2010-07-01

102

Seleção de clones de batata-doce resistentes a Meloidogyne incognita raça 1 / Selection of sweetpotato clones resistant to Meloidogyne incognita race 1  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese O objetivo deste trabalho foi selecionar clones de batata-doce (Ipomoea batatas) resistentes à raça 1 de Meloidogyne incognita e avaliar a eficiência do método de seleção empregado, pela estimação dos coeficientes de variação genética e ambiental e das herdabilidades no sentido amplo. Foram utilizad [...] os 123 genótipos de batata-doce, entre os quais quatro cultivares comerciais - Brazlândia Rosada, Brazlândia Roxa, Brazlândia Branca e Palmas -, e 119 acessos previamente selecionados no programa de melhoramento vegetal da Universidade Federal de Lavras. O delineamento experimental utilizado foi o de blocos aumentados, com três tratamentos comuns: as cultivares de batata-doce Brazlândia Branca e Palmas, e a cultivar de tomate Santa Clara, suscetível ao nematoide. A classificação dos níveis de resistência foi realizada de acordo com o fator de reprodução do nematoide e o índice de reprodução relativo à cultivar Santa Clara, de tomateiro. A relação entre os coeficientes de variação genética e ambiental e as herdabilidades no sentido amplo foram altas, tanto para o fator de reprodução quanto para o índice de reprodução dos nematoides, o que demonstra a eficiência do método empregado para a seleção de genótipos resistentes. Foram identificados 57 genótipos promissores de batata-doce, resistentes à raça 1 de M. incognita, e selecionados para continuar no programa de melhoramento. Abstract in english The objective of this work was to select sweetpotato (Ipomoea batatas) resistant clones to Meloidogyne incognita race 1, and to assess the efficiency of the selection method deployed, through the estimation of genetic and environmental coefficients of variation, and broad-sense heritabilities. Genot [...] ypes assessed comprised 123 sweetpotato entries altogether, including four commercial cultivars - Brazlândia Rosada, Brazlândia Roxa, Brazlândia Branca, Palmas - and 119 clones previously selected by the Universidade Federal de Lavras sweetpotato breeding program. The experimental setup was a an augmented block design, using three common treatments: the sweetpotato cultivars Brazlândia branca and Palmas, and the nematode-susceptible tomato cultivar Santa Clara. Nematode resistance levels were defined both by the nematode reproduction factor and by the nematode reproduction index relative to tomato cv. Santa Clara. The ratio between genetic and environmental coefficients of variation and the broad-sense heritability estimates were high, for both nematodes reproduction factor and reproduction index, indicating that the selection method deployed was efficient for the selection of resistant genotypes. Fifty-seven sweetpotato clones were identified as resistant to M. incognita race 1, and selected to continue in the sweetpotato breeding program.

Aline, Marchese; Wilson Roberto, Maluf; Álvaro Carlos, Gonçalves Neto; Ranoel José de Sousa, Gonçalves; Luiz Antonio Augusto, Gomes.

2010-09-01

103

Uso de agentes microbianos e químico para o controle de Meloidogyne incognita em soja / Use of microbial and chemical agents to control Meloidogyne incognita in soybean  

Scientific Electronic Library Online (English)

Full Text Available Nematoides de galhas constituem importante grupo de patógenos da cultura da soja e o manejo integrado é uma das principais medidas de controle que visam à redução de perdas econômicas. Neste trabalho foi avaliada a eficácia dos fungos Paecilomyces lilacinus (Thom.) Samsom e Pochonia chlamydosporia ( [...] Goddard) Zare & Gams (sinonímia Verticillium chlamydosporium), de um produto comercial à base de Bacillus sp. (Nemix) e do nematicida químico Aldicarb no controle de Meloidogyne incognita em soja, variedade M-SOY 6101. O experimento foi realizado em casa-de-vegetação no delineamento experimental de blocos casualizados com nove tratamentos (três produtos biológicos usados no tratamento de sementes com ou sem a aplicação em pós-emergência, Aldicarb aplicado apenas em pós-emergência e duas testemunhas) e quatro repetições. Aldicarb reduziu o número de ovos e de juvenis do nematoide. P. lilacinus foi o mais atuante dos agentes biológicos, favorecendo a manutenção da quantidade de matéria seca da raiz de soja e reduzindo o número de ovos. O produto Nemix e P. chlamydosporia somente tiveram ação efetiva na redução do número de ovos do nematoide. Com base nos resultados, foi possível concluir que o agente químico e os agentes biológicos avaliados neste trabalho tiveram moderada atividade no controle de M. incognita em soja. Abstract in english Root-knot nematodes are considered significant pathogens of soybean crops. The objective of this work was to evaluate the efficacy of two fungi (Paecilomyces lilacinus (Thom.) Samsom and Pochonia chlamydosporia (Goddard) Zare & Gams (syn. Verticillium chlamydosporium), a commercial product based on [...] Bacillus sp. and Aldicarb on the control of Meloidogyne incognita on soybean, cultivar M-SOY 6101. The experimental design was set as randomized blocks with four replications. Nine treatments were evaluated: three biological agents used for seed treatment with and without post-emergence application, Aldicarb on post-emergence only, and two controls. All treatments were inoculated with the nematode, except for a blank control where only water was applied. One control-only treated with the nematode was also included. Aldicarb could reduce the number of eggs and juveniles in the roots. P. lilacinus showed the best performance among the biological control agents, reducing the number of eggs and increasing dry root weight. Nemix, a Bacillus sp. based commercial product and P. chlamydosporia could only reduce significantly the number of eggs of the nematode. In this work, it was possible to conclude that the chemical and biological agents showed a moderate activity in the control of M. incognita in soybean.

Henrique Teixeira, Nunes; Antonio Carlos, Monteiro; Alan William Vilela, Pomela.

2010-09-01

104

Seleção de clones de batata-doce resistentes a Meloidogyne incognita raça 1 Selection of sweetpotato clones resistant to Meloidogyne incognita race 1  

Directory of Open Access Journals (Sweden)

Full Text Available O objetivo deste trabalho foi selecionar clones de batata-doce (Ipomoea batatas resistentes à raça 1 de Meloidogyne incognita e avaliar a eficiência do método de seleção empregado, pela estimação dos coeficientes de variação genética e ambiental e das herdabilidades no sentido amplo. Foram utilizados 123 genótipos de batata-doce, entre os quais quatro cultivares comerciais - Brazlândia Rosada, Brazlândia Roxa, Brazlândia Branca e Palmas -, e 119 acessos previamente selecionados no programa de melhoramento vegetal da Universidade Federal de Lavras. O delineamento experimental utilizado foi o de blocos aumentados, com três tratamentos comuns: as cultivares de batata-doce Brazlândia Branca e Palmas, e a cultivar de tomate Santa Clara, suscetível ao nematoide. A classificação dos níveis de resistência foi realizada de acordo com o fator de reprodução do nematoide e o índice de reprodução relativo à cultivar Santa Clara, de tomateiro. A relação entre os coeficientes de variação genética e ambiental e as herdabilidades no sentido amplo foram altas, tanto para o fator de reprodução quanto para o índice de reprodução dos nematoides, o que demonstra a eficiência do método empregado para a seleção de genótipos resistentes. Foram identificados 57 genótipos promissores de batata-doce, resistentes à raça 1 de M. incognita, e selecionados para continuar no programa de melhoramento.The objective of this work was to select sweetpotato (Ipomoea batatas resistant clones to Meloidogyne incognita race 1, and to assess the efficiency of the selection method deployed, through the estimation of genetic and environmental coefficients of variation, and broad-sense heritabilities. Genotypes assessed comprised 123 sweetpotato entries altogether, including four commercial cultivars - Brazlândia Rosada, Brazlândia Roxa, Brazlândia Branca, Palmas - and 119 clones previously selected by the Universidade Federal de Lavras sweetpotato breeding program. The experimental setup was a an augmented block design, using three common treatments: the sweetpotato cultivars Brazlândia branca and Palmas, and the nematode-susceptible tomato cultivar Santa Clara. Nematode resistance levels were defined both by the nematode reproduction factor and by the nematode reproduction index relative to tomato cv. Santa Clara. The ratio between genetic and environmental coefficients of variation and the broad-sense heritability estimates were high, for both nematodes reproduction factor and reproduction index, indicating that the selection method deployed was efficient for the selection of resistant genotypes. Fifty-seven sweetpotato clones were identified as resistant to M. incognita race 1, and selected to continue in the sweetpotato breeding program.

Aline Marchese

2010-09-01

105

Nematicidal activity of fervenulin isolated from a nematicidal actinomycete, Streptomyces sp. CMU-MH021, on Meloidogyne incognita  

OpenAIRE

An isolate of the actinomycete, Streptomyces sp. CMU-MH021 produced secondary metabolites that inhibited egg hatch and increased juvenile mortality of the root-knot nematode Meloidogyne incognita in vitro. 16S rDNA gene sequencing showed that the isolate sequence was 99% identical to Streptomyces roseoverticillatus. The culture filtrates form different culture media were tested for nematocidal activity. The maximal activity against M. incognita was obtained by using modified basal (MB) medium...

Ruanpanun, Pornthip; Laatsch, Hartmut; Tangchitsomkid, Nuchanart; Lumyong, Saisamorn

2010-01-01

106

COMPORTAMIENTO DE GENOTIPOS DE LA FAMILIA SOLANACEAE FRENTE A Meloidogyne incognita (KOFOID Y WHITE) CHITWOOD1 / BEHAVIOUR OF GENOTYPES FROM SOLANACEA FAMILY IN FRONT TO Meloidogyne incognita (KOFOID Y WHITE) CHITWOOD1  

Scientific Electronic Library Online (English)

Full Text Available Los nematodos formadores de agallas (Meloidogyne spp.) constituyen factores limitantes de los rendimientos en la producción de hortalizas en campo abierto y casas de cultivo, donde el tomate (Solanum lycopersicum L. (ex Lycopersicon esculentum Mill)) representa un buen hospedante de estos nematodos. [...] Para manejar las poblaciones de estos organismos, entre otras tácticas se hace uso de genotipos resistentes o se acude al injerto herbáceo para obtener resultados productivos favorables, resultando necesaria la evaluación de los genotipos a emplear frente a poblaciones nativas, pues se sabe que la resistencia puede ser quebrada por factores tales como la virulencia de la población de Meloidogyne. El objetivo de este estudio fue determinar el comportamiento de líneas, híbridos y variedades de tomate ante una población nativa de M. incognita raza 2, como elemento básico del programa de injerto herbáceo que se desarrolla en Cuba para contar con alternativas al bromuro de metilo. Se inocularon 10 plantas por genotipo, con 1,5 huevos/juveniles.g de suelo-1 y se evaluaron a los 60 días, determinándose el Índice de Agallamiento (IA), Factor de Reproducción (FR) e índice de reproducción (IR). Los cultivares evaluados fueron Lycopersicon peruvianum acc. B6-140; Physalis ixocarpa acc. B6236; Lycopersicon pimpinelifolium acc. Mex 121-A; las variedades/híbridos de S. lycopersicum var. cerasiforme, Vyta, Mariela, Amalia, HC 3880 y HA 3019; el híbrido inter-específico Lycopersicon hirsutum x L. esculentum, Solanum torvum y los híbridos de tomate T-1x14, T-1x15, T-2x16 y LTM. Resultó inmune L. hirsutum x L. esculentum y muy resistentes S. torvum y L. peruvianum. Por su parte, P. ixocarpa se comportó como moderadamente resistente y el resto de los materiales evaluados fueron susceptibles a la población cubana de M. incognita raza 2. Abstract in english The root knot nematodes (Meloidogyne spp.) are limiting factors for yields of vegetables in open areas and crops under shelter conditions, where tomato Solanum lycopersicon L. (ex Lycopersicon esculentum Mill.) represents a very good host for these nematodes. For population management of this pest, [...] resistance and graffing are used, among other tactics, to obtain good productive results, but it is necessary to evaluated the resistance of genotypes to native populations, since as it is know resistancemay be broken by factors like virulence of Meloidogyne population. The objective of this study was to determine the behaviour of tomato lines hybrids and varieties to native population of M. incognita race 2, as a basic element for the graffting program being develop in Cuba as an alternative to methyl bromide. Ten plants per genotype were inoculated with 1,5 eggs/juvenils.g of soil-1 and evaluated after 60 days to determined the Root Galling Index (IA), the Reproduction Factor (FR) and the Reproduction Index (IR). The cultivars evaluated were Lycopersicon peruvianum acc. B6-140; Physalis ixocarpa acc. B6236; Lycopersicon pimpinellifolium acc. Mex 121-A; the following varieties/hybrids of Solanum lycopersicum var. ceraciforme, Vyta, Mariela, Amalia, HC 3880 and HA 3019; the interespecific hybrid Lycopersicon hirsutum x L. esculentum, Solanum torvum and the tomato hybrids T-1x14, T-1x15, T-2x16 and LTM. The interespecific hybrid L. hirsutum x L. esculentum was immune, whereas S. torvum and L. peruvianum were very resistant. In other hand, P. ixocarpa behaved as moderately resistant and the rest of genotypes were susceptibles to the Cuban population of M. incognita race 2.

Mayra G, Rodríguez; Lucila, Gómez; Farah M, González; Yudines, Carrillo; Maite, Piñón; Olimpia, Gómez; A.S, Casanova; Martha, Álvarez; Belkis, Peteira.

2009-12-01

107

Effect of Meloidogyne incognita on Plant Nutrient Concentration and Its Influence on the Physiology of Beans  

OpenAIRE

Phaseolus vulgaris plants, 3, 8, 11, and 13 days old, were inoculated with 0, 2,000, 4,000, or 8,000 second-stage Meloidogyne incognita larvae and maintained under controlled conditions. The photosynthetic rate and the shoot and root concentration of K, Ca, Mn, Fe, Cu, and Zn were determined by destructive assay at 1-27-day intervals and by nondestructive assay of leaves, stems, and roots at 27 or 28 days after inoculation. In the destructive assay, the concentration of the elements in the pl...

Melakeberhan, H.; Webster, J. M.; Brooke, R. C.; D Auria, J. M.; Cackette, M.

1987-01-01

108

Use of Avermectins for the Control of Meloidogyne incognita on tomatoes  

OpenAIRE

The efficacy of avermectins B? and B? for control of Meloidogyne incognita on tomato was studied in pots and field plots for two seasons. Avermectins were applied as granules and liquid in furrows or by low pressure drip irrigation systems, at rates ranging from 0.093 to 0.34 kg a.i./ha, as single or multiple applications. Levels of control comparable to those obtained by oxamyl and aldicarb at 3.36 kg a.i./ha were achieved by the avermectin with only 1/10 the volume of chemicals applied ...

Garabedian, Sahag; Gundy, S. D.

1983-01-01

109

Evaluation of NemX, a New Cultivar of Cotton with High Resistance to Meloidogyne incognita  

OpenAIRE

The level of resistance to root-knot nematode, Meloidogyne incognita, in NemX, a new cultivar of the Acala-type upland cotton, was evaluated in relation to four resistant breeding lines (N6072, N8577, N901, and N903) and four susceptible cultivars (Maxxa, SJ2, Royale, and Prema). In growth pouch tests, an average of only 4 nematode egg masses was produced on roots of NemX or the resistant lines, compared to a significantly higher average of 21 on the susceptible cultivars. In pot tests, the n...

Ogallo, J. L.; Goodell, P. B.; Eckert, J.; Roberts, P. A.

1997-01-01

110

Resistance induction for Meloidogyne incognita in sugarcane through mineral organic fertilizers  

Directory of Open Access Journals (Sweden)

Full Text Available The effects of Coda Radimax (CR, Coda Humus-PK (CH and Coda Vit (CV on the induction of resistance for Meloidogyne incognita in sugarcane (Saccharum sp. varieties (RB92579, RB863129, RB867515 through nematode reproduction, plant development and root anatomy analysis, emphasizing the differences of the lignin deposition, and cortex-vascular cylinder proportions were investigated. In 90 days after inoculation with eggs of M. incognita, CR reduced the number of eggs per root system in all the sugarcane varieties; CH and CV reduced eggs density in RB867515; CR increased stalk number in RB92579 and fresh weight of shoots in RB863129 and RB92579; CH increased plant height in RB92579 and fresh weight of shoots in RB92579 and RB867515, CV affected fresh weigh of shoots and roots of RB863129. All the tested compounds did not affect stalk diameter, number and dry weight of shoots. Cross-sections of roots showed no anatomical changes in the M. incognita inoculated tissues.Este estudo investigou, em condições de casa de vegetação, os efeitos de três complexos organo-minerais (Coda Radimax, Coda Humus-PK e Coda Vit na indução de resistência a Meloidogyne incognita em três variedades: RB92579, RB863129, RB867515 de cana-de-açúcar (Saccharum sp., considerando-se a reprodução do nematóide, desenvolvimento das plantas e anatomia das raízes, com ênfase a diferenças na deposição de lignina e proporções do córtex e cilindro vascular. As avaliações foram efetuadas 90 dias após a inoculação com 5000 ovos de M. incognita por planta. Em relação à testemunha, Coda Radimax reduziu significativamente o número final de ovos por sistema radicular em todas as variedades. Coda Humus-PK e Coda Vit se mostraram eficientes em diminuir a densidade de ovos em RB867515, mas não em RB863129. Todos os compostos testados não afetaram o diâmetro do colmo, peso da biomassa seca da parte aérea e número de perfilho. Coda Radimax aumentou significativamente o número de colmos em RB92579 e a biomassa fresca da parte aérea em RB863129 e RB92579. Coda Humus-PK aumentou significativamente a altura da planta em RB92579 e a biomassa fresca da parte aérea em RB92579 e RB867515, enquanto Coda Vit afetou, significativamente, a biomassa fresca da parte aérea e raízes de RB863129. Fundamentando-se nas sessões transversais obtidas das raízes de cada variedade de cana observada sob microscópio ótico, não ocorreram modificações anatômicas significativas nos tecidos inoculados com M. incognita em relação aos tecidos sadios.

Andréa Chaves

2009-12-01

111

Resistance induction for Meloidogyne incognita in sugarcane through mineral organic fertilizers  

Scientific Electronic Library Online (English)

Full Text Available Este estudo investigou, em condições de casa de vegetação, os efeitos de três complexos organo-minerais (Coda Radimax, Coda Humus-PK e Coda Vit) na indução de resistência a Meloidogyne incognita em três variedades: RB92579, RB863129, RB867515 de cana-de-açúcar (Saccharum sp.), considerando-se a repr [...] odução do nematóide, desenvolvimento das plantas e anatomia das raízes, com ênfase a diferenças na deposição de lignina e proporções do córtex e cilindro vascular. As avaliações foram efetuadas 90 dias após a inoculação com 5000 ovos de M. incognita por planta. Em relação à testemunha, Coda Radimax reduziu significativamente o número final de ovos por sistema radicular em todas as variedades. Coda Humus-PK e Coda Vit se mostraram eficientes em diminuir a densidade de ovos em RB867515, mas não em RB863129. Todos os compostos testados não afetaram o diâmetro do colmo, peso da biomassa seca da parte aérea e número de perfilho. Coda Radimax aumentou significativamente o número de colmos em RB92579 e a biomassa fresca da parte aérea em RB863129 e RB92579. Coda Humus-PK aumentou significativamente a altura da planta em RB92579 e a biomassa fresca da parte aérea em RB92579 e RB867515, enquanto Coda Vit afetou, significativamente, a biomassa fresca da parte aérea e raízes de RB863129. Fundamentando-se nas sessões transversais obtidas das raízes de cada variedade de cana observada sob microscópio ótico, não ocorreram modificações anatômicas significativas nos tecidos inoculados com M. incognita em relação aos tecidos sadios. Abstract in english The effects of Coda Radimax (CR), Coda Humus-PK (CH) and Coda Vit (CV) on the induction of resistance for Meloidogyne incognita in sugarcane (Saccharum sp.) varieties (RB92579, RB863129, RB867515) through nematode reproduction, plant development and root anatomy analysis, emphasizing the differences [...] of the lignin deposition, and cortex-vascular cylinder proportions were investigated. In 90 days after inoculation with eggs of M. incognita, CR reduced the number of eggs per root system in all the sugarcane varieties; CH and CV reduced eggs density in RB867515; CR increased stalk number in RB92579 and fresh weight of shoots in RB863129 and RB92579; CH increased plant height in RB92579 and fresh weight of shoots in RB92579 and RB867515, CV affected fresh weigh of shoots and roots of RB863129. All the tested compounds did not affect stalk diameter, number and dry weight of shoots. Cross-sections of roots showed no anatomical changes in the M. incognita inoculated tissues.

Andréa, Chaves; Elvira Maria Régis, Pedrosa; Rejane Magalhães de Mendonça, Pimentel; Rildo Sartori Barbosa, Coelho; Lílian Margarete Paes, Guimarães; Sandra Roberta Vaz Lira, Maranhão.

1393-14-01

112

Efecto del Vermicompost y Quitina sobre el control de meloidogyne incognita en tomate a nivel de invernadero / Effect of vermicompost and chitin on the control of Meloidogyne incognita in greenhouse tomato  

Scientific Electronic Library Online (English)

Full Text Available Meloidogyne incognita es un nematodo endoparásito sedentario, de penetración total y formador de nódulos radicales; tiene una amplia distribución geográfica y causa pérdidas agrícolas importantes. Recientemente se han utilizado abonos orgánicos y compuestos como la quitina en la supresión de plagas [...] y enfermedades de plantas. El objetivo de esta investigación fue evaluar el efecto de la aplicación de vermicompost de estiércol bovino y su enriquecimiento con quitina, sobre la infección de M. incognita en plantas de tomate var. Hayslip bajo condiciones de invernadero. Para esto se inocularon las plantas con 5000 unidades de inóculo (huevos+juveniles en segundo estado) por maceta y se compararon con controles que fueron sembrados en suelo sin enmienda orgánica o quitina. La evaluación se llevó a cabo 60 días después y se midió el peso fresco aéreo y radical, peso seco aéreo, población total de nematodos en raíz y suelo, índice de nódulos radicales (INR), índice de masas de huevos (IMH), el factor de reproducción del nematodo (FR) y recuento de grupos funcionales (hongos, bacterias y actinomicetes). La adición al suelo de vermicompost provocó un incremento en las variables peso fresco y seco foliar y peso fresco radical: a mayor porcentaje de vermicompost, mayor incremento; así mismo, la aplicación del vermicompost redujo la cantidad del nematodo en raíz y en suelo. La aplicación de quitina acentuó estos resultados, obteniéndose el menor factor de reproducción de M. Incognita, con un valor de 3,76 para la dosis de 50% vermicompost+quitina, mientras que en el testigo este factor fue de 93,20. La aplicación de quitina como enmienda única solo afectó la población de hongos en el suelo, mientras que la de actinomicetes aumentó en los tratamientos enmendados Abstract in english Meloidogyne incognita is a sedentary endoparasitic nematode, with total penetration and gall-forming; it has a wide geographical distribution and causes significant agricultural losses. Recently, organic fertilizers and compounds such as chitin have been used in the suppression of plant pests and di [...] seases. The aim of this study was to evaluate the effect of applying cattle manure vermicompost, and its enrichment with chitin, on the infection of M. incognita in tomato plants var. Hayslip under greenhouse conditions. For this purpose, plants were inoculated with 5000 units of eggs+second stage juveniles per pot and were compared with controls grown in soil without organic amendment or chitin. The evaluation was carried out 60 days afterwards: the shoot and root fresh weight, shoot dry weight, total population in root and soil nematodes, root knot index (INR), rate of egg masses (IMH), the nematode reproduction factor (FR) and functional-groups numbers (fungi, bacteria and actinomycetes) were measured. The addition of vermicompost to soil caused an increase in the variables of shoot fresh and dry weight and fresh root weight: the higher the percentage of vermicompost, the higher the increase; likewise, the application of vermicompost reduced the number of nematodes both in root and soil. The application of chitin accentuated these results by bringing about the lowest reproduction factor of M. incognita, with a value of 3.76 for the dose of vermicompost+50% chitin, whereas in the control this factor had a value of 93.20. The application of chitin as sole amendment affected only the soil fungi population, while the actinomycetes population nincreased in the amended treatments

Leida, Castro; Lorena, Flores; Lidieth, Uribe.

2011-12-01

113

Efectividad de hongos nematófagos sobre Meloidogyne incognita (Kofoid y White) Chitwood en tomate en condiciones de campo, Loja, Ecuador / Effectiveness of nematophagous fungi on Meloidogyne incognita (Kofoid and White) Chitwood on tomato in field conditions in Loja, Ecuador  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish El objetivo del presente trabajo fue determinar el efecto de varios aislamientos autóctonos de los hongos Pochonia chlamydosporia (Goddard) Zare y Gams (Hypocreales: Clavicipitaceae) y Purpureocillium lilacinum Luansa-ard et al. (Hypocreales: Ophiocordycipitaceae) en el control de Meloidogyne incogn [...] ita (Kofoid y White) Chitwood, en tomate, en condiciones de campo. Se utilizaron seis aislamientos fúngicos y un control sin aplicación, distribuidos según un diseño de bloques al azar con cuatro réplicas. Las aplicaciones de los hongos lograron reducir el índice de agallamiento por M. incognita, así como las poblaciones de juveniles infestivos (J2) en el suelo y en las raíces del cultivo, a la vez que se observó un estímulo en las variables agronómicas número de frutos, masa de los frutos y rendimiento agrícola. Estos resultados constituyen una contribución a la solución del problema de los nematodos formadores de agalla, en el cultivo del tomate en las condiciones de Loja, Ecuador, con recursos locales, no agresivos al medio ambiente. Abstract in english This work was aimed to evaluate the effect of isolates of the fungi Pochonia chlamydosporia (Goddard) Zare and Gams (Hypocreales: Clavicipitaceae) and Purpureocillium lilacinum Luansa-ard et al. (Hypocreales: Ophiocordycipitaceae) in the Meloidogyne incognita (Kofoid and White) Chitwood control in t [...] omato in field conditions. The assay comprised six fungic isolates and a control without fungi, in a ramdomized block design. In treated plants the gall index and the nematode population in roots and in the soil were reduced in comparison with the untreated plots. The number of fruits, the weight of fruits and yields were enhanced in the plots treated with the fungi. These results are a contribution to the solution of the root-knot nematode problem in the conditions of Loja, Ecuador, with local resources and no harmful to the environment.

Tulio F., Solano Castillo; Marcia L., Castillo Ávila; José V., Medina Medina; Elio M., del Pozo Núñez.

2014-12-01

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Direct identification of the Meloidogyne incognita secretome reveals proteins with host cell reprogramming potential.  

Science.gov (United States)

The root knot nematode, Meloidogyne incognita, is an obligate parasite that causes significant damage to a broad range of host plants. Infection is associated with secretion of proteins surrounded by proliferating cells. Many parasites are known to secrete effectors that interfere with plant innate immunity, enabling infection to occur; they can also release pathogen-associated molecular patterns (PAMPs, e.g., flagellin) that trigger basal immunity through the nematode stylet into the plant cell. This leads to suppression of innate immunity and reprogramming of plant cells to form a feeding structure containing multinucleate giant cells. Effectors have generally been discovered using genetics or bioinformatics, but M. incognita is non-sexual and its genome sequence has not yet been reported. To partially overcome these limitations, we have used mass spectrometry to directly identify 486 proteins secreted by M. incognita. These proteins contain at least segmental sequence identity to those found in our 3 reference databases (published nematode proteins; unpublished M. incognita ESTs; published plant proteins). Several secreted proteins are homologous to plant proteins, which they may mimic, and they contain domains that suggest known effector functions (e.g., regulating the plant cell cycle or growth). Others have regulatory domains that could reprogram cells. Using in situ hybridization we observed that most secreted proteins were produced by the subventral glands, but we found that phasmids also secreted proteins. We annotated the functions of the secreted proteins and classified them according to roles they may play in the development of root knot disease. Our results show that parasite secretomes can be partially characterized without cognate genomic DNA sequence. We observed that the M. incognita secretome overlaps the reported secretome of mammalian parasitic nematodes (e.g., Brugia malayi), suggesting a common parasitic behavior and a possible conservation of function between metazoan parasites of plants and animals. PMID:18974830

Bellafiore, Stéphane; Shen, Zhouxin; Rosso, Marie-Noelle; Abad, Pierre; Shih, Patrick; Briggs, Steven P

2008-10-01

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Microorganismos Benéficos Asociados a Meloidogyne incognita (Kofoid y White) Chitwood en Guayabo (Psidium guajava L.) de Calvillo, Aguascalientes, México / Beneficent Microorganisms Associated to Meloidogyne incognita (Kofoid & White) Chitwood in Guava (Psidium guajava L.) of Calvillo, Aguascalientes, México  

Scientific Electronic Library Online (English)

Full Text Available Se identificó a Meloidogyne incognita como la especie del nematodo agallador que parásita al cultivo del guayabo, en la región de Calvillo (Aguascalientes, México). También se aisló hongos y bacterias benéficos asociados a suelo y raíces colectadas en las localidades de Cerro Blanco, Mesa Grande, La [...] Labor y Malpaso. Veinte muestras distintas de Meloidogyne sp., fueron identificadas tomando en cuenta las características de patrones perineales de las hembras adultas así como por la observación de la región anterior de los machos. La especie Meloidogyne incognita fue identificada en todas las muestras. Los microorganismos benéficos aislados y asociados a la rizósfera del guayabo con uso potencial en control biológico, pertenecen a las especies de Bacillus cereus, B. subtilis B. megaterium y Paecilomyces farinosus. Además los nematodos edáficos Rhabditis y Mononchus fueron identificados en las muestras. Abstract in english The root-knot nematode species Meloidogyne incognita was identified as the one species that parasites guava orchards in the Calvillo region (Aguascalientes, Mexico). Beneficent fungi and bacteria were isolated as well, associated to soil and roots collected from the Cerro Blanco, Mesa Grande, La Lab [...] or and Malpaso locations. Twenty different Meloidogyne sp., samples were identified taking adult female perinea pattern characteristics into account, as well as the male anterior region observation. The Meloidogyne incognita species was identified in all the samples. The isolated beneficent microorganisms and associated to guava rhizosphere with a potential use in biological control, belong to the Bacillus cereus, B. subtilis B. megaterium and Paecilomyces farinosus species. Furthermore, the Rhabditis and Mononchus soil nematodes were identified in the samples.

Gabriel, Gallegos-Morales; Melchor, Cepeda-Siller; Francisco Daniel, Hernández-Castillo; Ana María, Acosta-Zamarripa; Rodolfo, Velásquez-Valle; Ernesto, González-Gaona; Juan Manuel, Sánchez-Yánez.

116

Efecto de extractos acuosos de dos meliaceas sobre Meloidogyne incognita (Nematoda, meloidogynidae)  

Scientific Electronic Library Online (English)

Full Text Available SciELO Mexico | Language: Spanish Abstract in spanish Se evaluó la bioactividad de seis extractos acuosos al 10% y 30% (P/V), conteniendo terpenoides de Melia azedarach y Trichilia glauca (Meliaceae) en su constitución química, sobre la plaga Meloidogyne incognita (Nematoda, Meloidogynidae). Los resultados muestran que los productos naturales ensayados [...] poseen una buena actividad nematicida, ya que ejercieron efectos letales moderados (mortalidad: 23-46.2%, dependiendo del tratamiento). Estos datos indican que las interesantes propiedades de ambas Meliaceae podrían utilizarse en el manejo de este nematode en huertas, en reemplazo de los nematicidas sintéticos. Abstract in english The bioactivity of six aqueous extracts 10% and 30% (P/V), containing terpenoids from Melia azedarachand Trichilia glauca (Meliaceae) in their chemical constitution, was evaluated against the pest Meloidogyne incognita (Nematoda, Meloidogynidae). Results show that the natural products assayed had a [...] good nematicidal activity, because they had moderate lethal effects (mortality: 23-46.2%, depending upon treatment). These data show that the interesting properties of both Meliaceae could be used in orchard nematode management, in replacement of synthetic nematicides.

Graciela, Mareggiani; Norma, Zamuner; Gisella, Angarola.

2010-04-01

117

Nematicidal activity of chaetoglobosin A poduced by Chaetomium globosum NK102 against Meloidogyne incognita.  

Science.gov (United States)

The nematicidal activity of Chaetomium globosum NK102, culture filtrates, and chaetoglobosin A (ChA) purified by HPLC was evaluated on Meloidogyne incognita . The results showed that C. globosum NK102 significantly repelled second-stage juveniles (J2s). Both filtrates and ChA demonstrated strong adverse effects on J2 mortality with 99.8% at 300 ?g ChA/mL (LC(50) = 77.0 ?g/mL) at 72 h. ChA and filtrates did not affect egg hatch until 72 h of exposure. All filtrate treatments inhibited the J2 penetration even in 12.5% dilution treatment. Similarly, ChA (300 and 30 ?g/mL) showed a significant inhibitory effect on J2 penetration. The number of eggs per plant was significantly reduced in the treatment of 30 mg ChA/kg soil by 63% relative to control plants, indicating the apparent negative effect on reproduction of M. incognita. The study demonstrated the nematicidal activity of ChA and suggested that it could be a potential biocontrol agent for integrated management of M. incognita. PMID:23214998

Hu, Yang; Zhang, Weipu; Zhang, Ping; Ruan, Weibin; Zhu, Xudong

2013-01-01

118

Chemical composition and nematicidal activity of essential oil of Agastache rugosa against Meloidogyne incognita.  

Science.gov (United States)

The aim of this research was to determine the chemical composition and nematicidal activity of essential oil of Agastache rugosa flowering aerial parts against the root knot nematode, Meloidogyne incognita, and to isolate and identify any nematicidal constituents from the essential oil. The essential oil of A. rugosa aerial parts was obtained by hydrodistillation and analyzed by GC-FID and GC-MS. A total of 37 components of the essential oil were identified, with the principal compounds being methyleugenol (50.51%), estragole (8.55%), and eugenol (7.54%), followed by thymol (3.62%), pulegone (2.56%), limonene (2.49%) and caryophyllene (2.38%). Based on bioactivity-guided fractionation, the three active constituents were isolated from the essential oil and identified as methyleugenol, estragole and eugenol. The essential oil of A. rugosa exhibited strong nematicidal activity against M. incognita, with a LC50 value of 47.3 ?g/mL. The components eugenol (LC50 = 66.6 ?g/mL) and methyleugenol (LC50 = 89.4 ?g/mL) exhibited stronger nematicidal activity against M. incognita (LC50 = 185.9 ?g/mL). The results indicate that the essential oil of A. rugosa aerial parts and its constituent compounds have potential for development into natural nematicides for control of the root knot nematode. PMID:23571530

Li, He Qin; Liu, Qi Zhi; Liu, Zhi Long; Du, Shu Shan; Deng, Zhi Wei

2013-01-01

119

Chemical Composition and Nematicidal Activity of Essential Oil of Agastache rugosa against Meloidogyne incognita  

Directory of Open Access Journals (Sweden)

Full Text Available The aim of this research was to determine the chemical composition and nematicidal activity of essential oil of Agastache rugosa flowering aerial parts against the root knot nematode, Meloidogyne incognita, and to isolate and identify any nematicidal constituents from the essential oil. The essential oil of A. rugosa aerial parts was obtained by hydrodistillation and analyzed by GC-FID and GC-MS. A total of 37 components of the essential oil were identified, with the principal compounds being methyleugenol (50.51%, estragole (8.55%, and eugenol (7.54%, followed by thymol (3.62%, pulegone (2.56%, limonene (2.49% and caryophyllene (2.38%. Based on bioactivity-guided fractionation, the three active constituents were isolated from the essential oil and identified as methyleugenol, estragole and eugenol. The essential oil of A. rugosa exhibited strong nematicidal activity against M. incognita, with a LC50 value of 47.3 ?g/mL. The components eugenol (LC50 = 66.6 ?g/mL and methyleugenol (LC50 = 89.4 ?g/mL exhibited stronger nematicidal activity against M. incognita (LC50 = 185.9 ?g/mL. The results indicate that the essential oil of A. rugosa aerial parts and its constituent compounds have potential for development into natural nematicides for control of the root knot nematode.

Zhi Wei Deng

2013-04-01

120

Histopathological Studies of Eggplant Roots as Affected by IAA, Agrobacterium tumefaciens and Meloidogyne incognita Alone and in Combinations  

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Full Text Available The anatomy of eggplant roots as affected by the application of IAA, Agrobacterium tumefaciens and Meloidogyne incognita alone and in combination was studied. IAA and A. tumefaciens, alone and in combination increased the root diameter, cortex thickness, number of cortex layers, stele diameter, number of xylem vessels but decreased the vessel diameter. Inoculation with M. incognita led to the formation of multinucleated giant cells surrounded by deformed xylem elements, hypertrophy of the cortex and hyperplasia of the pericycle. More giant cells with higher dimensions were formed and more eggs/egg mass were produced in plants where IAA, A. tumefaciens alone or in combination was introduced with M. incognita. On the other hand, the presence of IAA, A. tumefaciens or their combination extended the life-span of giant cells, providing long-lasting feeding sites for the nematode. The auxin-mediated role of A. tumefaciens in development and reproduction of M. incognita was discussed.

Mohamed A. Elwakil

2003-01-01

121

Behavior of Ilex paraguariensis St. Hilaire, 1822 to Meloidogyne incognita and M. paranaensis and their influence on development of plantlets  

Directory of Open Access Journals (Sweden)

Full Text Available The influence of Meloidogyne incognita and M. paranaensis on the development of mate (Ilex paraguariensis ST. Hill plantlets was assessed in greenhouse and laboratory. The experimental design was randomized. Every plot of each one of the 10 repetitions contained one mate plantlet , inoculated with 5,000 eggs of M. incognita (races 1, 2, 3 and 4 and M. paranaensis. After 120 days it was observed that mate was a reliable hostess to such nematodes and that they could finish their life cycle. Plant development was significantly modified by M. incognita, races 1 and 2. Dry and green matter weight of shoots changed according to treatment. No changes were observed in fresh root weight. The number of eggs per root was similar for M. incognita, races 1 and 2, and higher for the other treatments. The reproduction factor was above 1 for all treatments, indicating mate plants susceptibility to them.A influência de Meloidogyne incognita e M paranaensis no desenvolvimento de mudas de erva-mate, foi avaliada em casa-de-vegetação e laboratório. O delineamento experimental foi inteiramente casualizado, com 10 repetições, sendo cada parcela formada de 1 plântula de erva-mate/vaso, inoculada com 5000 ovos de M. incognita raças 1, 2, 3, 4 e M. paranaensis. Aos 120 dias, observou-se que a erva-mate, além de boa hospedeira destes nematóides, permitiu-lhes completar seu ciclo vital. O desenvolvimento das plantas foi significativamente afetado pelas raças 1 e 2 de M. incognita.; os pesos de matéria seca e fresca da parte aérea sofreram alterações conforme o tratamento. Não houve alteração no peso fresco de raízes e o número de ovos por raízes foi semelhante para as raças 1 e 2 de M. incognita, sendo, porém, mais elevado nos demais tratamentos. O fator de reprodução foi superior a 1 em todos os tratamentos, indicando a susceptibilidade da erva-mate a estes agentes.

Débora Cristina Santiago

2000-01-01

122

Reação de genótipos de milho ao parasitismo de Meloidogyne incognita raça 1 e a M. paranaensis / Reaction of corn genotypes to parasitism from Meloidogyne incognita breed 1and M. paranaensis  

Scientific Electronic Library Online (English)

Full Text Available 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 resistênci [...] a 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 Abstract in english 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 paranae [...] nsis 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

Ricardo Michael, Levy; Martin, Homechin; Débora Cristina, Santiago; Marina Capparelli, Cadioli; Fernando César, Baida.

2009-12-01

123

Knocking-Down Meloidogyne incognita Proteases by Plant-Delivered dsRNA Has Negative Pleiotropic Effect on Nematode Vigor  

OpenAIRE

The root-knot nematode Meloidogyne incognita causes serious damage and yield losses in numerous important crops worldwide. Analysis of the M. incognita genome revealed a vast number of proteases belonging to five different catalytic classes. Several reports indicate that M. incognita proteases could play important roles in nematode parasitism, besides their function in ordinary digestion of giant cell contents for feeding. The precise roles of these proteins during parasitism however are stil...

Antonino Souza Ju?nior, Jose? Dijair; Ramos Coelho, Roberta; Tristan Lourenc?o, Isabela; Da Rocha Fragoso, Rodrigo; Barbosa Viana, Antonio Ame?rico; Lima Pepino Macedo, Leonardo; Mattar Da Silva, Maria Cristina; Gomes Carneiro, Regina Maria; Engler, Gilbert; Almeida-engler, Janice; Grossi-de-sa, Maria Fatima

2013-01-01

124

Registro da ocorrência de Meloidogyne incognita no porta-enxerto 'IAC 766-Campinas' no estado de Pernambuco e reação de porta-enxertos e de cultivares copa de videira a Meloidogyne spp. / Meloidogyne incognita report on 'IAC 766-Campinas' rootstock in the state of Pernambuco and reaction of grape rootstocks and cultivars to Meloidogyne spp.  

Scientific Electronic Library Online (English)

Full Text Available Relata-se a ocorrência de Meloidogyne incognita (Est. I2) em pomar de videira na cidade de Petrolina, Pernambuco. Plantas da cultivar Festival enxertadas sobre 'IAC 766-Campinas', atacadas por Meloidogyne incognita, apresentavam sintomas de menor vigor, folhas amarelecidas e folhagem mais esparsa, e [...] raízes com numerosas galhas em meio ao cultivo de feijão-de-porco (Canavalia ensiformis), também atacado pelo nematoide. Com o objetivo de avaliar a resistência de quatro porta-enxertos tropicais, oito de clima temperado, e as cultivares Niágara Rosada e Chardonnay quanto à reação a M. incognita e M. arenaria, em casa de vegetação, realizou-se este trabalho. Mudas das videiras, mantidas em vaso com solo esterilizado, foram inoculadas com 10.000 ovos + J2 de M. incognita ou M. arenaria por planta. Decorridos oito meses da inoculação, cada planta foi avaliada quanto ao número de galhas e número de ovos por planta, determinando-se, a seguir, o fator de reprodução de cada espécie do nematoide (FR=população inicial/população final) nos diferentes materiais testados. Entre os porta-enxertos avaliados, 'Harmony', 'Salt Creek', '1103 Paulsen', 'IAC 572-Jales', 'IAC 313-Tropical', 'K5BB Kober' e 'SO4', foram resistentes (FR1,00) ao nematoide. No entanto, ambas as cultivares copa foram suscetíveis às duas espécies de Meloidogyne testadas. Abstract in english The occurrence of root-knot nematode Meloidogyne incognita (Est. I2) is reported in grapevine in Petrolina municipality, State of Pernambuco. Grape plants of Festival cultivar grafted on the 'IAC 766 - Campinas' rootstock attacked by M. incognita exhibited symptoms of less vigorous growth, yellowing [...] and sparse leaves and multiple galls in the root system in an area cultivated with jack-bean (Canavalia ensiformis) also infected by the same nematode. In order to evaluate resistance of four tropical rootstocks, eight temperate and two cultivars Chardonnay and Niagara Rosada in reaction to M. incognita and M. arenaria, this study was carried out. Seedlings of the investigated grapevine genotypes were maintained in pots with sterilized soil and subsequently inoculated with 10,000 eggs + J2 of M. incognita or M. arenaria per plant in a six replicate design. Eight months after nematode inoculation, each plant was evaluated by counting gall and eggs. The final number of eggs (FP) of each Meloidogyne specie was calculated and the reproductive factor (RF = FP/IP), determined. Among the tested rootstocks, 'Harmony', 'Salt Creek', '1103 Paulsen', 'IAC 572-Jales', 'IAC 313-Tropical', 'K5BB Kober', 'SO4' , were resistant (RF1.00) to M. arenaria. In contrast, both tested grapevine scion cultivars were susceptible to the investigated Meloidogyne species.

Lúcia, Somavilla; Cesar Bauer, Gomes; Vera Maria, Quecini.

2012-09-01

125

Effects of insect cadavers infected by Heterorhabditis bacteriophora and Steinernema diaprepesi on Meloidogyne incognita parasitism in pepper and summer squash plants / Efecto de insectos cadáveres infectados por Heterorhabditis bacteriophora y Steinernema diaprepesi sobre el parasitismo de Meloidogyne incognita en plantas de pimiento y zapallito redondo de tronco  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: English Abstract in spanish E.E. Del Valle, P. Lax, J. Rondán Dueñas y M.E. Doucet. 2013. Efecto de insectos cadáveres infectados por Heterorhabditis bacteriophora y Steinernema diaprepesi sobre el parasitismo de Meloidogyne incognita en plantas de pimiento y zapallito redondo de tronco. Cien. Inv. Agr. 40(1):109-118. El efect [...] o de cadáveres de insectos infectados con tres aislados de Heterorhabditis bacteriophora y un aislado de Steinernema diaprepesi sobre una población de Meloidogyne incognita en plantas de pimiento (Capsicum annuum) y zapallito redondo de tronco (Cucurbita maxima) fue evaluado en experiencias de invernadero conducidas en Santa Fe (Argentina). Los cadáveres de insectos necesarios para la experiencia se obtuvieron infectando larvas de último estadio de Galleria mellonella y Tenebrio monitor con nematodos entomopatógenos. Dos cadáveres de seis días de infección se colocaron debajo de la superficie del suelo de macetas que fueron inoculadas con 100 juveniles de segundo estadio de M. incognita. A los sesenta días se registraron los siguientes parámetros en cada planta: número de hojas, peso seco de la parte aérea, número de agallas, masas de huevos y huevos, y número de agallas, masas de huevos y huevos g-1 de materia fresca radical. En pimiento, la única variable afectada por los cadáveres en relación al testigo fue el número de huevos de M. incognita en el tratamiento de cadáveres de T. molitor infectados con H. bacteriophora aislado Rama Caída. En zapallito redondo de tronco, varios tratamientos provocaron una disminución en el número de agallas y masas de huevos. Sólo la aplicación de cadáveres de G. mellonella infectados con H. bacteriophora aislado Rama Caída demostró ser eficiente en reducir el número de huevos de M. incognita. Nuestros resultados indicaron que la aplicación de cadáveres de insectos infectados con los nematodos entomopatógenos estudiados podría reducir los daños causados por M. incognita en plantas de pimiento y zapallito redondo de tronco. Abstract in english E. E. Del Valle, P. Lax, J. Rondán Dueñas, and M. E. Doucet. 2013. Effects of insect cadavers infected by Heterorhabditis bacteriophora and Steinernema diaprepesi on Meloidogyne incognita parasitism in pepper and summer squash plants. Cien. Inv. Agr. 40(1):109-118. The effects of insect cadavers inf [...] ected with three isolates of Heterorhabditis bacteriophora and one isolate of Steinernema diaprepesi on a population of Meloidogyne incognita in pepper (Capsicum annuum) and summer squash (Cucurbita maxima) were evaluated in greenhouse experiments carried out in Santa Fe (Argentina). Insect cadavers were obtained for the experiments from last instar larvae of Galleria mellonella and Tenebrio molitor that had been infected with entomopathogenic nematodes. Two six-day-old insect cadavers per pot were placed below the soil surface, and the soil was inoculated with 100 second-stage juveniles ofM incognita. Sixty days after inoculation, the following parameters were recorded for each plant: number of leaves; dry weight of aerial parts; numbers of galls, egg masses and eggs; and numbers of galls, egg masses and eggs g-1 of root fresh matter. In pepper, the only variable affected by the infected cadavers with respect to control was the number of eggs in the treatment involving T. molitor cadavers infected with the H. bacteriophora isolate Rama Caída. In summer squash, several treatments using infected cadavers resulted in a decrease in the numbers of galls and egg masses. Only the treatment involving G. mellonella cadavers infected with the H. bacteriophora isolate Rama Caída proved to be efficient in reducing the number of M. incognita eggs. Our results indicated that the application of insect cadavers infected with the entomopathogenic nematodes studied might reduce M. incognita damage in pepper and summer squash plants.

Eleodoro E, Del Valle; Paola, Lax; Juan, Rondán Dueñas; Marcelo E, Doucet.

2013-04-01

126

Rotations with Coastal Bermudagrass and Fallow for Management of Meloidogyne incognita and Soilborne Fungi on Vegetable Crops  

OpenAIRE

The efficacy of fallow and coastal bermudagrass (Cynodon dactylon) as a rotation crop for control of root-knot nematode (Meloidogyne incognita race 1) and soilborne fungi in okra (Hibiscus esculentus cv. Emerald), squash (Cucurbita pepo cv. Dixie Hybrid), and sweet corn (Zea mays cv. Merit) was evaluated in a 3-year field trial. Numbers of M. incognita in the soil and root-gall indices were greater on okra and squash than sweet corn and declined over the years on vegetable crops following fal...

Johnson, A. W.; Burton, G. W.; Wilson, J. P.; Golden, A. M.

1995-01-01

127

Isolation of nematicidal triterpenoid saponins from Pulsatilla koreana root and their activities against Meloidogyne incognita.  

Science.gov (United States)

Pulsatilla koreana, a species endemic to Korea, is an important herb used in traditional medicine to treat amoebic dysentery and malaria. In the present study, 23 oleanane-type triterpenoid saponins 1-23 and eight lupane-type triterpenoid saponins 24-31 were isolated from the roots of P. koreana. Their structures were elucidated on the basis of spectroscopic data. The methanol extract and isolated compounds were next assessed for nematicidal activity against the root-knot nematode (Meloidogyne incognita). The methanol extract showed strong nematicidal activity after 48 h, with a LC?? value of 92.8 ?g/mL. Compounds 2, 5, 9, 20, and 21 showed significant effects, with LC?? values ranging from 70.1 to 94.7 ?g/mL after 48 h. These results suggest that triterpenoid saponins from P. koreana should be explored as potential natural nematicides for developing new agents to control root-knot nematode disease. PMID:23698044

Li, Wei; Sun, Ya Nan; Yan, Xi Tao; Yang, Seo Young; Lee, Suk Jun; Byun, Hyo Jeung; Moon, Chang Sup; Han, Byung Soo; Kim, Young Ho

2013-01-01

128

Transcriptome Analysis of Resistant and Susceptible Alfalfa Cultivars Infected With Root-Knot Nematode Meloidogyne incognita  

Science.gov (United States)

Nematodes are one of the major limiting factors in alfalfa production. Root-knot nematodes (RKN, Meloidogyne spp.) are widely distributed and economically important sedentary endoparasites of agricultural crops and they may inflict significant damage to alfalfa fields. As of today, no studies have been published on global gene expression profiling in alfalfa infected with RKN or any other plant parasitic nematode. Very little information is available about molecular mechanisms that contribute to pathogenesis and defense responses in alfalfa against these pests and specifically against RKN. In this work, we performed root transcriptome analysis of resistant (cv. Moapa 69) and susceptible (cv. Lahontan) alfalfa cultivars infected with RKN Meloidogyne incognita, widespread root-knot nematode species and a major pest worldwide. A total of 1,701,622,580 pair-end reads were generated on an Illumina Hi-Seq 2000 platform from the roots of both cultivars and assembled into 45,595 and 47,590 transcripts in cvs Moapa 69 and Lahontan, respectively. Bioinformatic analysis revealed a number of common and unique genes that were differentially expressed in susceptible and resistant lines as a result of nematode infection. Although the susceptible cultivar showed a more pronounced defense response to the infection, feeding sites were successfully established in its roots. Characteristically, basal gene expression levels under normal conditions differed between the two cultivars as well, which may confer advantage to one of the genotypes toward resistance to nematodes. Differentially expressed genes were subsequently assigned to known Gene Ontology categories to predict their functional roles and associated biological processes. Real-time PCR validated expression changes in genes arbitrarily selected for experimental confirmation. Candidate genes that contribute to protection against M. incognita in alfalfa were proposed and alfalfa-nematode interactions with respect to resistance are discussed. PMID:25710378

Postnikova, Olga A.; Hult, Maria; Shao, Jonathan; Skantar, Andrea; Nemchinov, Lev G.

2015-01-01

129

Transcriptome Analysis of Resistant and Susceptible Alfalfa Cultivars Infected With Root-Knot Nematode Meloidogyne incognita.  

Science.gov (United States)

Nematodes are one of the major limiting factors in alfalfa production. Root-knot nematodes (RKN, Meloidogyne spp.) are widely distributed and economically important sedentary endoparasites of agricultural crops and they may inflict significant damage to alfalfa fields. As of today, no studies have been published on global gene expression profiling in alfalfa infected with RKN or any other plant parasitic nematode. Very little information is available about molecular mechanisms that contribute to pathogenesis and defense responses in alfalfa against these pests and specifically against RKN. In this work, we performed root transcriptome analysis of resistant (cv. Moapa 69) and susceptible (cv. Lahontan) alfalfa cultivars infected with RKN Meloidogyne incognita, widespread root-knot nematode species and a major pest worldwide. A total of 1,701,622,580 pair-end reads were generated on an Illumina Hi-Seq 2000 platform from the roots of both cultivars and assembled into 45,595 and 47,590 transcripts in cvs Moapa 69 and Lahontan, respectively. Bioinformatic analysis revealed a number of common and unique genes that were differentially expressed in susceptible and resistant lines as a result of nematode infection. Although the susceptible cultivar showed a more pronounced defense response to the infection, feeding sites were successfully established in its roots. Characteristically, basal gene expression levels under normal conditions differed between the two cultivars as well, which may confer advantage to one of the genotypes toward resistance to nematodes. Differentially expressed genes were subsequently assigned to known Gene Ontology categories to predict their functional roles and associated biological processes. Real-time PCR validated expression changes in genes arbitrarily selected for experimental confirmation. Candidate genes that contribute to protection against M. incognita in alfalfa were proposed and alfalfa-nematode interactions with respect to resistance are discussed. PMID:25710378

Postnikova, Olga A; Hult, Maria; Shao, Jonathan; Skantar, Andrea; Nemchinov, Lev G

2015-01-01

130

Management of Meloidogyne incognita with Chemicals and Cultivars in Cotton in a Semi-Arid Environment  

Science.gov (United States)

Management of Meloidogyne incognita (root-knot nematode) in cotton in the United States was substantially affected by the decision to stop production of aldicarb by its principle manufacturer in 2011. The remaining commercially available tools to manage M. incognita included soil fumigation, nematicide seed treatments, postemergence nematicide application, and cultivars partially resistant to M. incognita. Small plot field studies were conducted on a total of nine sites from 2011–2013 to examine the effects of each of these tools alone or in combinations, on early season galling, late-season nematode density in soil, yield, and value ($/ha = lint value minus chemical costs/ha). The use of a partially resistant cultivar resulted in fewer galls/root system at 35 d after planting in eight of nine tests, lower root-knot nematode density late in the growing season for all test sites, higher lint yield in eight of nine sites, and higher value/ha in six of nine sites. Galls per root were reduced by aldicarb in three of nine sites and by 1,3-dichloropropene (1,3-D) in two of eight sites, relative to the nontreated control (no insecticide or nematicide treatment). Soil fumigation reduced M. incognita density late in the season in three of nine sites. Value/ha was not affected by chemical treatment in four of nine sites, but there was a cultivar × chemical interaction in four of nine sites. When value/ha was affected by chemical treatment, the nontreated control had a similar value to the treatment with the highest value/ha in seven of eight cultivar-site combinations. The next “best” value/ha were associated with seed treatment insecticide (STI) + oxamyl and aldicarb (similar value to the highest value/ha in six of eight cultivar-site combinations). The lowest valued treatment was STI + 1,3-D. In a semi-arid region, where rainfall was low during the spring for all three years, cultivars with partial resistance to M. incognita was the most profitable method of managing root-knot nematode in cotton. PMID:24987161

Wheeler, T. A.; Siders, K. T.; Anderson, M. G.; Russell, S. A.; Woodward, J. E.; Mullinix, B. G.

2014-01-01

131

Management of Meloidogyne incognita with Chemicals and Cultivars in Cotton in a Semi-Arid Environment.  

Science.gov (United States)

Management of Meloidogyne incognita (root-knot nematode) in cotton in the United States was substantially affected by the decision to stop production of aldicarb by its principle manufacturer in 2011. The remaining commercially available tools to manage M. incognita included soil fumigation, nematicide seed treatments, postemergence nematicide application, and cultivars partially resistant to M. incognita. Small plot field studies were conducted on a total of nine sites from 2011-2013 to examine the effects of each of these tools alone or in combinations, on early season galling, late-season nematode density in soil, yield, and value ($/ha = lint value minus chemical costs/ha). The use of a partially resistant cultivar resulted in fewer galls/root system at 35 d after planting in eight of nine tests, lower root-knot nematode density late in the growing season for all test sites, higher lint yield in eight of nine sites, and higher value/ha in six of nine sites. Galls per root were reduced by aldicarb in three of nine sites and by 1,3-dichloropropene (1,3-D) in two of eight sites, relative to the nontreated control (no insecticide or nematicide treatment). Soil fumigation reduced M. incognita density late in the season in three of nine sites. Value/ha was not affected by chemical treatment in four of nine sites, but there was a cultivar × chemical interaction in four of nine sites. When value/ha was affected by chemical treatment, the nontreated control had a similar value to the treatment with the highest value/ha in seven of eight cultivar-site combinations. The next "best" value/ha were associated with seed treatment insecticide (STI) + oxamyl and aldicarb (similar value to the highest value/ha in six of eight cultivar-site combinations). The lowest valued treatment was STI + 1,3-D. In a semi-arid region, where rainfall was low during the spring for all three years, cultivars with partial resistance to M. incognita was the most profitable method of managing root-knot nematode in cotton. PMID:24987161

Wheeler, T A; Siders, K T; Anderson, M G; Russell, S A; Woodward, J E; Mullinix, B G

2014-06-01

132

Comportamiento de cuatro cultivares de Cucurbita maxima cv. zapallito frente al parasitismo del nematodo de las agallas Meloidogyne incognita  

Scientific Electronic Library Online (English)

Full Text Available SciELO Argentina | Language: Spanish Abstract in spanish El nematodo de las agallas, Meloidogyne incognita, es causante de pérdidas productivas en los principales cultivos hortícolas que se realizan en el albardón costero santafesino. El objetivo de la investigación fue determinar la reacción de cuatro cultivares comerciales de zapallito redondo de tronco [...] (Cucurbita maxima cv. zapallito) frente al parasitismo de M. incognita. Las experiencias se condujeron en macetas bajo invernadero y se evaluaron los cultivares Nacional, Premier, Sais superselección y Máximo. Los tratamientos consistieron en inocular plantas de cada cultivar con 100 juveniles de segundo estadio de M. incognita y de sus correspondientes testigos no inoculados. A los 45 días de la inoculación se determinó el número de agallas, Índice de Agallas, número de masas de huevos, Índice de Masas de Huevos, número de huevos y el factor e reproducción. Los cuatro cultivares estudiados demostraron ser susceptibles a M. incognita. Abstract in english The root-knot nematode, Meloidogyne incognita, causes yield losses in many horticultural crops in the coastal área of Santa Fe province. The aim of this research was to determine the reaction of four commercial cultivars of summer squash (Cucurbita maxima cv. zapallito) when parasitized by M. incogn [...] ita. The experiments were conducted in pots under greenhouse conditions and Nacional, Premier, Sais superselection and Máximo cultivars were evaluated. The treatments consisted of plants of each cultivar inoculated with 100 second-stage juveniles of M. incognita and its corresponding control. 45 days after inoculation the number of galls, Gall Index, number of egg masses, Eggs Mass Index, number of eggs and reproduction factor were determined. The four cultivars studied showed susceptibility to M. incognita.

E.E, Del Valle; A.M, Guzmán; A.M, Belavi; M, Soressi.

2013-12-01

133

Enxertia e sua influencia na produção de pepino e reprodução de Meloidogyne javanica e M. incognita Effect of grafting on cucumber production and reproduction of Meloidogyne javanica and M. incognita  

OpenAIRE

A enxertia em porta-enxertos resistentes é uma técnica frequentemente recomendada para a cultura do pepino em áreas infestadas com nematoides-das-galhas. O presente trabalho teve como objetivo avaliar a produção de pepino enxertado em dois porta-enxertos comparado com pé-franco em solo infestado com Meloidogyne incognita raça 2 ou com M. javanica. Foram avaliados nove tratamentos (fatorial 3x3: pepino híbrido Tsuyataro pé-franco, enxertado na abóbora híbrida 'Shelper' e enxertado n...

Salata, Ariane C.; Erick Vinicius Bertolini; Magro, Felipe O.; Ii, Antonio Cardoso; Wilcken, Silvia Renata S.

2012-01-01

134

Chitosan-cinnamon beads enhance suppressive activity against Rhizoctonia solani and Meloidogyne incognita in vitro.  

Science.gov (United States)

A novel chitosan-cinnamon bead carrier was prepared in this study. Chitosan was mixed with cinnamon powder (CP) and cinnamon extract (CE) to obtain chitosan-cinnamon powder (CCP) beads and chitosan-cinnamon extracted (CCE) beads, respectively. The potential antifungal and nematicidal activities of CCP and CCE were investigated against Rhizoctonia solani and Meloidogyne incognita in vitro. Relative antifungal activity of the CCP (5% CP) bead-treated R. solani was 30.9 and 23.9% after 1 and 2 day incubations, respectively. Relative antifungal activity of the CCE (0.5% CE) bead-treated R. solani was 4.3, 3.0 and 4.2% after 1, 2 and 3 days of incubation. Inhibition of hatch by CCP beads with CP of 5% was 78.8%. Inhibition of hatch by CCE beads with CE of 0.5% was 82.0%. J2 mortality following the CCP (5% CP) and CCE (0.5% CE) bead treatments was 85.0 and 95.8%, respectively against M. incognita after 48 h incubations. PMID:24417978

Seo, Dong-Jun; Nguyen, Dang-Minh-Chanh; Park, Ro-Dong; Jung, Woo-Jin

2014-01-01

135

Survival of Paecilomyces lilacinus in Selected Carriers and Related Effects on Meloidogyne incognita on Tomato.  

Science.gov (United States)

Laboratory and microplot experiments were conducted to determine the influence of carrier and storage of Paecilomyces lilacinus on its survival and related protection of tomato against Meloidogyne incognita. Spores of P. lilacinus were prepared in five formulations: alginate pellets (pellets), diatomaceous earth granules (granules), wheat grain, soil, and soil plus chitin. Fungal viability was high in wheat and granules, intermediate in pellets, and low in soil and chitin-amended soil stored at 25 +/- 2 C. In 1985 P. lilacinus in field microplots resulted in about a 25% increase in tomato yield and 25% gall suppression, compared with nematodes alone. Greatest suppression of egg development occurred in plots treated with P. lilacinus in pellets, wheat grain, and granules. In 1986 carryover protection of tomato against M. incognita resulted in about a threefold increase in tomato fruit yield and 25% suppression of gall development, compared with plants treated with nematodes alone. Higher numbers of fungus-infected egg masses occurred in plots treated with pellets (32%) than in those treated with chitin-amended soil (24%), wheat (16%), granules (12%), or soil (7%). Numbers of fungal colony-forming units per gram of soil in plots treated with pellets were 10-fold greater than initial levels estimated at planting time in 1986. PMID:19287586

Cabanillas, E; Barker, K R; Nelson, L A

1989-01-01

136

Potent nematicidal activity of phthalaldehyde, salicylaldehyde, and cinnamic aldehyde against Meloidogyne incognita.  

Science.gov (United States)

The nematicidal activity of selected aromatic aldehydes was tested against the root knot nematode Meloidogyne incognita. The most active aldehyde was phthalaldehyde (1) with an EC(50) value of 11 ± 6 mg/L followed by salicylaldehyde (2) and cinnamic aldehyde (3) with EC(50) values of 11 ± 1 and 12 ± 5 mg/L, respectively. On the other hand, structurally related aldehydes such as 2-methoxybenzaldehyde (21), 3,4-dimethoxybenzaldehyde, and vanillin (23) were not active at the concentration of 1000 mg/L. By liquid chromatography-mass spectrometry the reactivity of tested aldehydes against a synthetic peptide resembling the nematode cuticle was characterized. At the test concentration of 1 mM, the main adduct formation was observed for 3,4-dihydroxybenzaldehyde (22), 2-methoxybenzaldehyde (21), and 3,4-dimethoxybenzaldehyde. Considering that 2-methoxybenzaldehyde (21) and 3,4-dimethoxybenzaldehyde were not active against M. incognita in in vitro experiments led us to hypothesize a different mechanism of action rather than an effect on the external cuticle modification of nematodes. When the toxicity of the V-ATPase inhibitor pyocyanin (10) was tested against M. incognita J2 nematodes, an EC(50) at 24 h of 72 ± 25 mg/L was found. The redox-active compounds such as phthalaldehyde (1) and salicylaldehyde (2) may share a common mode of action inhibiting nematode V-ATPase enzyme. The results of this investigation reveal that aromatic redox-active aldehydes can be considered as potent nematicides, and further investigation is needed to completely clarify their mode of action. PMID:23379671

Caboni, Pierluigi; Aissani, Nadhem; Cabras, Tiziana; Falqui, Andrea; Marotta, Roberto; Liori, Barbara; Ntalli, Nikoletta; Sarais, Giorgia; Sasanelli, Nicola; Tocco, Graziella

2013-02-27

137

Expression of Resistance to Meloidogyne incognita in Kenaf Cultivars (Hibiscus cannibinus under Field Conditions  

Directory of Open Access Journals (Sweden)

Full Text Available Field studies were conducted in 2003 and 2004 to investigate the reaction of 10 varieties of kenaf to natural infestation of Meloidogyne incognita. Ten weeks after planting, ten randomly selected plants per variety were assessed for root galling. Plants were carefully uprooted soil adhering to roots was washed off under a gentle stream of tap water and roots then were observed using a stereo microscope. Eggs were extracted from the roots with sodium hypochlorite. The reproduction factor (Pf / Pi was calculated. Data were collected on plant height, stem girth, days to maturity, number of seeds and seed yield and the final figures of these parameters were analyzed by of variance and mean separation by Duncan's Multiple Range Test. Gall index and nematode reproduction factor varied significantly among the kenaf varieties. AU 64 recorded the tallest height of 2.2 m followed by Ex-Funtua, Ifeken 100 and G 45 whereas the lowest height was recorded for Ifeken 400 and Cuba 108. Days to maturity ranged from 120 to 135 days. Based on gall index ratings, AU64, Ex-Shika, Ex-Giwa, G 45 and the local variety were susceptible to M. incognita. Tianung 1 and Cuba 108 were very susceptible, whereas Ifeken 100 and 400 were resistant. Based on reproduction factor, AU 64, Ex-Shika, Ex-Giwa, G 45, Ex-Funtua and the local variety supported greater nematode reproduction, were good host to root-knot nematode, Tianung 1 and Cuba 108 were very susceptible while Ifeken 100 and Ifeken 400 were poor host to M. incognita.

A.A. Adegbite

2005-11-01

138

IDENTIFICACIÓN MORFOLÓGICA, MORFOMÉTRICA Y MOLECULAR DE Meloidogyne incognita EN HIGUERA (Ficus carica L. EN COSTA RICA  

Directory of Open Access Journals (Sweden)

Full Text Available El objetivo de este estudio fue identificar la especie de Meloidogyne asociada a dos plantaciones de higuera en Costa Rica. En marzo de 2012, en el distrito de Pacayas, provincia de Cartago, se detectaron agallas en los sistemas radicales de plantas de higuera (Ficus carica L. de dos fincas. De las raíces agalladas se extrajeron hembras, masas de huevos y juveniles (J2 de Meloidogyne sp. Se examinaron los patrones perineales de las hembras y los segundos estadios infectivos se analizaron morfológica y molecularmente mediante PCR-RFLP. Se amplificó la región intergénica (IGS del genoma mitocondrial, delimitada por el gen de la subunidad II de la citocromo oxidasa (COII y el gen ribosomal 16S. La población de nematodos se identificó como M. incognita. El tamaño de los productos de PCR generados con los imprimadores C2F3 y 1108 fue de 1,7 kb. Al tratar los productos de PCR con enzimas de restricción, se generaron cuatro fragmentos de 850, 450, 250 y 150 pb con la enzima AluI y dos fragmentos de 1300 y 400 pb con la enzima HinfI.

Walter Peraza-Padilla

2013-01-01

139

Root Cortical Cell Spherical Bodies Associated with an Induced Resistance Reaction in Monoxenic Cultures of Meloidogyne incognita  

OpenAIRE

The root-knot nematode Meloidogyne incognita was monoxenically cultured on excised roots of soybean cv. Pickett and tomato cv. Rutgers in agar media containing either 0 to 1,600 ?g/ml ammonium nitrate or 0 to 100 ?g/ml urea. Observations with scanning and transmission electron microscopy indicated that an elevated concentration of ammonium nitrate or urea inhibited giant cell formation and suppressed nematode development in the infected soybean roots. In the tomato roots, concentrations of ...

Orion, D.; Wergin, W. P.; Chitwood, D. J.

1995-01-01

140

Nematocidal Flavone-C-Glycosides against the Root-Knot Nematode (Meloidogyne incognita) from Arisaema erubescens Tubers  

OpenAIRE

A screening of several Chinese medicinal herbs for nematicidal properties showed that Arisaema erubescens (Wall.) Schott tubers possessed significant nematicidal activity against the root-knot nematode (Meloidogyne incognita). From the ethanol extract, two nematicidal flavone-C-glycosides were isolated by bioassay-guided fractionation. The compounds were identified as schaftoside and isoschaftoside on the basis of their phytochemical and spectral data. Schaftoside and isoschaftoside possessed...

Zhi Long Liu; Yong Yan Wang; Zhi Wei Deng; Qi Zhi Liu; Cheng Fang Wang; Chun Qi Bai; Hai Ming Zhang; Shu Shan Du

2011-01-01

141

Effects of Site-specific Application of Aldicarb on Cotton in a Meloidogyne incognita-infested Field  

OpenAIRE

Cotton farmers in Missouri commonly apply a single rate of aldicarb throughout the field at planting to protect their crop from Meloidogyne incognita, even though these nematodes are spatially aggregated. Our purpose was to determine the effect of site-specific application of aldicarb on cotton production in a field infested with these nematodes in 1997 and 1998. Cotton yields were collected from sites not treated with aldicarb (control), sites receiving aldicarb at the standard recommended r...

Wrather, J. A.; Stevens, W. E.; Kirkpatrick, T. L.; Kitchen, N. R.

2002-01-01

142

Image Analysis of the Growth of Globodera pallida and Meloidogyne incognita on Transgenic Tomato Roots Expressing Cystatins  

OpenAIRE

An approach based on image analysis that enables rapid collection and analysis of nematode size and shape during growth is reported. This technique has been applied to assess Meloidogyne incognita and Globodera pallida during their development over 35 and 42 days, respectively, on transgenic tomato roots expressing the wild-type rice cystatin Oc-I or an engineered variant, Oc-IAD86. Morphometric values were established that subdivided enlarged saccate females from other life stages. Analysis ...

Atkinson, H. J.; Urwin, P. E.; Clarke, M. C.; Mcpherson, M. J.

1996-01-01

143

Efficacy Evaluation of Fungus Syncephalastrum racemosum and Nematicide Avermectin against the Root-Knot Nematode Meloidogyne incognita on Cucumber  

OpenAIRE

The root-knot nematode (RKN) is one of the most damaging agricultural pests.Effective biological control is need for controlling this destructive pathogen in organic farming system. During October 2010 to 2011, the nematicidal effects of the Syncephalastrum racemosum fungus and the nematicide, avermectin, alone or combined were tested against the RKN (Meloidogyne incognita) on cucumber under pot and field condition in China. Under pot conditions, the application of S. racemosum alone or combi...

Huang, Wen-kun; Sun, Jian-hua; Cui, Jiang-kuan; Wang, Gang-feng; Kong, Ling-an; Peng, Huan; Chen, Shu-long; Peng, De-liang

2014-01-01

144

Management of Meloidogyne incognita race 3 and Macrophomina phaseolina by fungus culture filtrates and Bacillus subtilis on chickpea  

OpenAIRE

#Bacillus subtilis$ et des filtrats de culture des champignons #Aspergillus niger, Curvularia tuberculata$ et #Penicillium coryophilum$ ont été utilisés, seuls ou en combinaison, comme traitement de semences pour protéger le pois chiche contre une maladie racinaire complexe associant le nématode "Meloidogyne incognita$ race 3 et le champignon #Macrophomina phaseolina$. D'une manière générale, les traitements à l'aide de ces quatre agents, seuls ou en combinaison, accroissent le poids...

Siddiqui, Z. A.; Mahmood, I.

1995-01-01

145

COMPORTAMIENTO DE MATERIALES GENÉTICOS DE PIÑA (Ananas comosus) AL ATAQUE DE Meloidogyne incognita RAZA 1 / BEHAVIOUR OF THE PINEAPPLE (Ananas comosus) GENETIC MATERIALS TO THE ATTACK OF Meloidogyne incognita RACE 1  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish La resistencia de cuatro accesiones de piña (Ananas comosus (L.) Merr.) a Meloidogyne incognita raza 1 procedentes de la región Amazónica Venezolana fue evaluada en invernadero. Las accesiones fueron identificadas como CRF-037, CRF-048, CRF-008 y CRF-040. El diseño experimental fue completamente ale [...] atorizado, con dos tratamientos y cinco repeticiones/accesión/tratamiento. Se utilizaron envases de 1 kg de suelo esterilizado con vapor. Un tratamiento estuvo representado por cinco plantas/accesión de un año de edad, las cuales se inocularon con una población inicial (Pi) de 10000 huevos y/o juveniles en segundo estado (J2). Otras cinco plantas/accesión no se inocularon y se utilizaron como testigos. El peso fresco y seco de la parte aérea y radical, además del Factor de Reproducción del nematodo (FR= Pf /Pi) se determinaron cuatro meses después de la inoculación. Los datos fueron analizados a través de una prueba t de Student para muestras independientes al 1%. Las plantas con FR=1 se consideraron resistentes y tolerantes, si no se afectaban las variables agronómicas. Los resultados demostraron que en las plantas inoculadas de la accesión CRF-008 los pesos frescos y secos de la parte aérea y el peso fresco radical fueron significativamente menores al compararlos con los de las plantas no inoculadas, mientras que en la accesión CRF-040 solo se afectó el peso fresco radical. El FR fue menor a uno en todas las accesiones, por lo que se pueden considerar en esta etapa del estudio como materiales resistentes. Las accesiones CRF-037 y CRF-048, se comportaron como resistentes tolerantes por no haberse afectado las variables agronómicas evaluadas, mientras que la accesión CRF-008 y CRF-040 se pueden catalogar como resistentes no tolerantes debido a que se afectaron tres y una de las variables agronómicas evaluadas, respectivamente. Estos materiales son promisorios en los programas de mejoramiento genético. Abstract in english Resistance to Meloidogyne incognita race 1 of four pineapple (Ananas comosus (L.) Merr.) accessions from the Venezuelan Amazonic region was evaluated under greenhouse conditions. Pineapple accessions were identified as CRF-037, CRF-048, CRF-008 and CRF-040. Pots of 1 kg of soil sterilized with steam [...] were used in a completely randomized design with two treatments and five replications/accession/treatment. One of the treatments was represented by five one-year old plants/accessions, which were inoculated with an initial population (Pi) of 10000 eggs and/or second stage juveniles (J2) of Meloidogyne incognita race 1. In the other treatment used as control, the five plants/accessions were not inoculated with nematodes. Fresh and dry weights of tops and roots and the nematode reproduction factor (RF= Pf /Pi) were recorded four months after inoculation. The data were analyzed by t Student test for independent samples at 1%. Plants with RF

Zoraida, Suárez H; Ligia Carolina, Rosales.

2008-12-01

146

Estreptomicetos no controle da meloidoginose em mudas de tomateiro / Streptomycetes in the control of Meloidogyne incognita in tomato plants  

Scientific Electronic Library Online (English)

Full Text Available Este trabalho teve como objetivo avaliar o efeito de seis isolados de estreptomicetos na mortalidade e eclosão de juvenis de segundo estádio (J2) de Meloidogyne incognita e no controle da meloidoginose em mudas de tomateiro. Foi montado um bioensaio em placas tipo Elisa, sendo adicionados em cada cé [...] lula, 200 µL de metabólitos dos isolados, com 20 µL de uma suspensão com 25 juvenis de segundo estádio (J2) de M. incognita. Os metabólitos produzidos por Streptomyces griseus subsp. griseus causaram 98,2% de mortalidade dos J2 de M. incognita. Em outro bioensaio, foram adicionados 3 mL dos metabólitos em frascos de vidro, com 100 µL da suspensão contendo 25 ovos de M.incognita. O isolado N0035 de Streptomyces proporcionou 98,8% de inibição na eclosão de J2 de M. incognita. Num terceiro bioensaio, o substrato de produção de mudas foi infestado com suspensão de estreptomicetos e incubado por 30 dias. Quinze dias depois da germinação das sementes do tomateiro, foi realizada a inoculação com 2.000 J2 por planta. Verificou-se a redução de 68% no número de galhas por grama de raiz e de 76,8% na massa de ovos por grama de raiz, nas mudas produzidas no substrato infestado e incubado com Streptomyces griseus subsp. griseus, quando comparado com a testemunha. Abstract in english This work aimed to evaluate the effect of six streptomycete isolates on mortality, hatching, and control of Meloidogyne incognita on tomato seedlings. An assay was conducted in Elisa plates, with the addition of 200 µL of the streptomycete metabolites, along with 20 µL of suspension containing 25 se [...] cond stage juveniles (J2) of M. incognita. The metabolites produced by Streptomyces griseus subsp. griseus caused mortality of 98.2% on M. incognita. A second assay was conducted with 3 mL of streptomycete metabolites and 25 eggs of M. incognita. The isolate N0035 of Streptomyces caused inhibition of 98.8% on hatching. In a third assay, potting mix was infested with suspension of the streptomycetes isolates and incubated for 30 days. Fifteen days after germination, tomato seedlings were inoculated with a suspension containing 2,000 J2 of M. incognita. Reductions of 68% in the number of galls per gram of roots and of 76.8% in the egg mass per gram of roots were observed on tomato seedlings grown in the potting mix inoculated with Streptomyces griseus subsp. griseus, compared to the control.

Carla da Silva, Sousa; Ana Cristina Fermino, Soares; Marlon da Silva, Garrido; Gabriela Maria Carneiro de Oliveira, Almeida.

1759-17-01

147

Estreptomicetos no controle da meloidoginose em mudas de tomateiro Streptomycetes in the control of Meloidogyne incognita in tomato plants  

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Full Text Available Este trabalho teve como objetivo avaliar o efeito de seis isolados de estreptomicetos na mortalidade e eclosão de juvenis de segundo estádio (J2 de Meloidogyne incognita e no controle da meloidoginose em mudas de tomateiro. Foi montado um bioensaio em placas tipo Elisa, sendo adicionados em cada célula, 200 µL de metabólitos dos isolados, com 20 µL de uma suspensão com 25 juvenis de segundo estádio (J2 de M. incognita. Os metabólitos produzidos por Streptomyces griseus subsp. griseus causaram 98,2% de mortalidade dos J2 de M. incognita. Em outro bioensaio, foram adicionados 3 mL dos metabólitos em frascos de vidro, com 100 µL da suspensão contendo 25 ovos de M.incognita. O isolado N0035 de Streptomyces proporcionou 98,8% de inibição na eclosão de J2 de M. incognita. Num terceiro bioensaio, o substrato de produção de mudas foi infestado com suspensão de estreptomicetos e incubado por 30 dias. Quinze dias depois da germinação das sementes do tomateiro, foi realizada a inoculação com 2.000 J2 por planta. Verificou-se a redução de 68% no número de galhas por grama de raiz e de 76,8% na massa de ovos por grama de raiz, nas mudas produzidas no substrato infestado e incubado com Streptomyces griseus subsp. griseus, quando comparado com a testemunha.This work aimed to evaluate the effect of six streptomycete isolates on mortality, hatching, and control of Meloidogyne incognita on tomato seedlings. An assay was conducted in Elisa plates, with the addition of 200 µL of the streptomycete metabolites, along with 20 µL of suspension containing 25 second stage juveniles (J2 of M. incognita. The metabolites produced by Streptomyces griseus subsp. griseus caused mortality of 98.2% on M. incognita. A second assay was conducted with 3 mL of streptomycete metabolites and 25 eggs of M. incognita. The isolate N0035 of Streptomyces caused inhibition of 98.8% on hatching. In a third assay, potting mix was infested with suspension of the streptomycetes isolates and incubated for 30 days. Fifteen days after germination, tomato seedlings were inoculated with a suspension containing 2,000 J2 of M. incognita. Reductions of 68% in the number of galls per gram of roots and of 76.8% in the egg mass per gram of roots were observed on tomato seedlings grown in the potting mix inoculated with Streptomyces griseus subsp. griseus, compared to the control.

Carla da Silva Sousa

2006-12-01

148

Effects of Peanut-Tobacco Rotations on Population Dynamics of Meloidogyne arenaria in Mixed Race Populations  

OpenAIRE

A 3-year microplot study was initiated to characterize the population dynamics, reproduction potential, and survivorship of single or mixed populations of Meloidogyne arenaria race 1 (Ma1) and race 2 (Ma2), as affected by crop rotations of peanut 'Florigiant' and M. incognita races 1 and 3-resistant 'McNair 373' and susceptible 'Coker 371-Gold' tobacco. Infection, reproduction, and root damage by Ma2 on peanut and by Ma1 on resistant tobacco were limited in the first year. Infection, reproduc...

Hirunsalee, Anan; Barker, K. R.; Beute, M. K.

1995-01-01

149

Efeitos do nível de inóculo de Meloidogyne incognita em algodoeiro / Effects of low inoculum level of Meloidogyne incognita on cotton plants  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Pesquisas acerca da fisiologia de plantas em resposta ao ataque de nematóides normalmente são feitas com doses altas de inóculo, quer sejam ovos ou juvenis de segundo estágio. Diferentemente, as avaliações da resistência de plantas a nematóides em programas de melhoramento são realizadas com doses b [...] astante inferiores. Neste estudo acompanhou-se a variação de alguns parâmetros fisiológicos em algodão, em resposta à aplicação de baixas doses de inóculo de Meloidogyne incognita raça 3. Duas cultivares foram utilizadas, Acala e IAC-20, respectivamente suscetível e moderadamente resistente. Plântulas com duas folhas receberam 500 ou 5.000 ovos e, 90 dias depois, foram comparadas a plantas que não receberam o inóculo, quanto à massa da parte aérea e raízes, fotossíntese, atividade da enzima redutase do nitrato e teores de clorofila e açúcares solúveis. Aos 90 dias algumas plantas também foram submetidas à deficiência hídrica e o potencial da água determinado nas folhas. O maior nível de inóculo levou à redução da parte aérea (massa de folhas) em 'Acala'. Com 500 ovos parece ter ocorrido um estímulo em ambas as cultivares, uma vez que houve tendência de maior crescimento da parte aérea. Em 'Acala' houve maior crescimento de raiz com o aumento do inóculo, provavelmente devido à emissão de raízes secundárias nos pontos de penetração do nematóide e também pela formação de galhas. Houve aumento dos teores de clorofila e de açúcares solúveis, bem como da fotossíntese, com o aumento do inóculo. Discute-se se tal ocorrência deve-se à maior demanda de fotoassimilados para suportar o crescimento de raízes, em 'Acala'. Em IAC-20 esse fato estaria ligado aos mecanismos de defesa induzidos pelo ataque do nematóide. Após o estresse hídrico o potencial da água diminuiu em 'IAC-20' e aumentou na 'Acala', com o aumento do inóculo. A elevação do potencial da água, nesta última cultivar, poderia estar ligada ao crescimento das raízes e, principalmente, à emissão de novas raízes secundárias, ao passo que a resposta em 'IAC-20' seria a previsível, ou seja, de deficiência hídrica. Abstract in english Investigations on physiological responses of plants to nematode are usually carried out with plants inoculated with high number of eggs or second-stage juveniles. On the other hand, resistance against nematodes in plant breeding programs is evaluated with low number of inoculum. The aim of this rese [...] arch was to study some physiological responses of cotton plants inoculated with low inoculum levels of Meloidogyne incognita race 3. Two cultivars were used, Acala and IAC-20, susceptible and moderately resistant hosts respectively. Seedlings with 500 or 5,000 eggs were compared with control plants at 90 days post inoculation. The following aspects were assessed: shoot and root masses, photosynthesis, activity of the enzyme nitrate reductase, and chlorophyll and soluble sugar contents. At 90 days a water stress was imposed to some plants and the leaf water potentials determined. At 5,000 eggs, 'Acala' had a shoot reduction (leafmass). With 500 eggs, there was an estimulation of shoot growth in both cultivars, as revealed by a shootmass increase There was a clear increase on root growth of 'Acala' which was directly related to the inoculum levels. This response was probably caused by emission of new secondary roots and nematode galls formation. Chlorophyll and sugar content, and photosynthesis increased with the increase of inoculum levels, suggesting a response to support root growth in 'Acala'. In 'IAC-20' these higher values would be related with the energy demanded by defense mechanisms against the nematode. The imposed water stress caused a decrease on leaf water potential in 'IAC-20', but an increase in 'Acala' with increasing inoculum levels. The observed increase in the later cultivar might be related with the root growth, mainly due to emission of new secondary roots, while 'IAC

MARLUCI MUNDIN, ABRÃO; PAULO, MAZZAFERA.

150

INFLUENCIA DE LA PLANTA HOSPEDANTE Y SU INTERACCIÓN CON Meloidogyne incognita SOBRE LA EFECTIVIDAD DE Pochonia chlamydosporia var. catenulata / INFLUENCE OF THE HOST PLANT AND ITS INTERACTION WITH Meloidogyne incognita ON THE EFFECTIVENESS OF Pochonia chlamydosporia var. catenulata  

Scientific Electronic Library Online (English)

Full Text Available El efecto de las plantas hospedantes y su interacción con Meloidogyne incognita (Kofoid y White) Chitwood sobre la efectividad de Pochonia chlamydosporia var. catenulata (Kamyscho ex Barron y Onions) Zare y Gams como agente de control biológico de nematodos formadores de agallas se estudió en condic [...] iones de aisladores biológicos. Para el desarrollo de la experiencia se utilizaron diferentes especies de plantas que se cultivan en los sistemas intensivos de producción de hortalizas en Cuba y se evaluó la colonización de la rizosfera, a partir del conteo de UFC del hongo, en plantas sanas e infestadas por M. incognita. Los resultados demostraron que el crecimiento del hongo en la rizosfera varió en dependencia de la especie de planta. Entre los mejores hospedantes de P. chlamydosporia var. catenulata estuvieron la col, coliflor y acelga china, cultivos resistentes a M. incognita. Las plantas infestadas por M. incognita mostraron mayores niveles de colonización del hongo que las plantas sanas y el cultivo de la habichuela resultó ser un buen hospedante, en presencia del nematodo. Se recomienda la utilización de estos cultivos dentro de esquemas de rotación que incluyan la aplicación de P. chlamydosporia var. catenulata como agente de control biológico para el manejo de M. incognita en sistemas intensivos de producción de hortalizas. Abstract in english The effect of the host plants and their interaction with Meloidogyne incognita (Kofoid and White) Chitwood on the effectiveness of Pochonia chlamydosporia var. catenulata (Kamyscho ex Barron and Onions) Zare and Gams as a biological control agent of root-knot nematodes was studied in glasshouse cond [...] itions. Different plant species from the Cuban Intensive Vegetable Production Systems were used to perform the experience. The growth of the fungus in the rhizosphere differed with the host plant. Among the best host plants of P. chlamydosporia var. catenulata were cabbage, salt-wort and cauliflower, resistant crops to M. incognita. The plants infested by M. incognita showed higher levels of fungus colonization than those healthy, and the kidney bean crop was a good host in the presence of the nematode. The use of these crops into rotation systems, with the application of Pochonia chlamydosporia var. catenulata as biological control agent for the management of M. incognita on Intensive Vegetable Production Systems, was recommended.

Ana, Puertas; L, Hidalgo-Díaz.

2007-08-01

151

Efeito de extratos aquosos de espécies de Asteraceae sobre Meloidogyne incognita Effect of aqueous extracts of Asteraceae species on Meloidogyne incognita  

Directory of Open Access Journals (Sweden)

Full Text Available Estudou-se, in vitro e in vivo a atividade nematicida dos extratos aquosos de vedélia (Sphagneticola trilobata, erva-de-touro (Tridax procumbens, cravo-de-defunto (Tagetes patula, girassol mexicano (Tithonia diversifolia, botão de ouro (Unxia suffruticosa e zínia (Zinnia peruviana, sobre Meloidogyne incognita. Os extratos foram preparados na proporção de 1,0g do material seco e triturado para 10mL de água destilada e armazenados por 24h, sendo seguidamente utilizados nos experimentos. Nos testes in vitro, foram depositados 4,0mL do extrato bruto e 2,0mL de uma suspensão aquosa contendo 200 ovos do nematóide em placas de Petri de 5cm de diâmetro e, quinze dias após, procedeu-se a contagem do número de juvenis eclodidos e dos ovos remanescentes para o cálculo das porcentagens de eclosão. Nos testes in vivo, os extratos foram aplicados, separadamente, via pulverização foliar, tratamento de raiz e vertido no solo, semanalmente durante 60 dias. Como testemunha utilizou-se apenas água nos dois experimentos. No ensaio in vitro observou-se que todos os extratos foram eficientes na redução da eclosão de juvenis de M. incognita quando comparados à testemunha, as porcentagens de redução foram 89,96%, 91,13%, 92,48%, 92,72%, 93,2% e 97,48% para erva-de-touro, cravo-de-defunto, girassol mexicano, vedélia, botão de ouro e zínia, respectivamente, e no ensaio in vivo, que os tratamentos não exerceram nenhum efeito sobre o peso do sistema radicular dos tomateiros, no entanto, observou-se que os resultados diferiram entre as espécies utilizadas e a forma de aplicação do extrato na avaliação do peso fresco da parte aérea das plantas. Quanto ao fator de reprodução, observou-se que nenhum dos extratos apresentou diferença estatística em relação à testemunha, no entanto, quando se compara as diferentes formas de aplicação dos mesmos, observa-se que houve diferença estatística quando os extratos de erva de touro e girassol mexicano foram aplicados via pulverização foliar e no tratamento de raiz, contudo, não houve diferença quando estes extratos foram aplicados em forma de rega no solo.The nematicide activity of aqueous extracts of Wedelia (Sphagneticola trilobata, tridax daisy (Tridax procumbens, marigold (Tagetes patula, Mexican sunflower (Tithonia diversifolia, "botão de ouro" (Unxia suffruticosa and Peruvian zinnia (Zinnia peruviana was studied in vitro and in vivo on Meloidogyne incognita. The extracts were prepared at a ratio of 1.0 g of dry and crushed material to 10 ml of distilled water, stored for 24 hours, and then used in the experiments. In in vitro tests, 4.0 mL of crude extract and 2.0 ml of an aqueous suspension containing 200 nematode eggs were deposited on Petri plates of 5cm diameter and, fifteen days later, the number of hatched juveniles and the remaining eggs were counted to calculate the percentages of hatching. In in vivo tests, the extracts were separately applied by leaf spraying, root treatment and pouring onto the soil, weekly for 60 days. As control, only water was used in both experiments. The in vitro test showed that all extracts were effective in reducing the hatching of juveniles of M. incognita when compared to the control; the reduction percentages were 89.96%, 91.13%, 92.48%, 92.72%, 93.2% and 97.48% for tridax daisy, marigold, Mexican sunflower, Wedelia, "botão de ouro" and Peruvian zinnia, respectively, while in the in vivo assay, treatments did not have any effect on the root system weight of tomato plants; however, results differed between the used species and the way of application of the extract in the evaluation of the fresh weight of shoots. As to the reproduction rate, none of the extracts showed a statistical difference, compared to control; however, comparing the different ways of application, there was statistical difference when the extracts of tridax daisy and Mexican sunflower were applied through leaf spraying and root treatment, but there was no difference when these extracts were applied as irrigation on the soil.

Isabel Cristina Madeira Ferreira

2013-03-01

152

Potential of sucrose and Pennisetum purpureum cv. Cameroon mulch on the management of Meloidogyne javanica and M. incognita  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Os efeitos da sacarose sobre a motilidade e a infectividade de juvenis de Meloidogyne javanica foram avaliados em condições de laboratório e casa-de-vegetação, usando açúcar mascavo e açúcar cristal. Os resultados indicaram que as soluções de açúcar mascavo e cristal reduziram a motilidade e promove [...] ram alterações morfológicas em juvenis dos nematóides in vitro. A eficiência da sacarose em grânulos e da sacarose em solução, com e sem a cobertura com matéria vegetal de capim elefante, na redução da reprodução e da população final de M. incognita raça 2 também foi avaliada. A sacarose em grânulos diminuiu os números de galhas e massas de ovos por sistema radicular e também de juvenis no solo. Para o ensaio com sacarose em solução, os melhores resultados para a redução da reprodução foram obtidos com a dose de 300 g de sacarose por litro de solo, aplicada a intervalos de sete dias, juntamente com a cobertura do solo com cobertura de matéria verde de capim-elefante. Abstract in english The effects of sucrose on motility and infectiveness of juveniles of Meloidogyne javanica were evaluated under laboratory and greenhouse conditions, using brown sugar and crystal sugar. Results showed that crystal and brown sugar solutions reduced motility and promoted morphological alterations of j [...] uvenile nematodes in vitro. The increasing dosages of sucrose reduced the number of galls and egg masses in tomato root by reducing the number of infective juveniles. The efficiency of granular sucrose, sucrose solution, with and without elephant-grass mulch, in the reduction of reproduction and final population of M. incognita race 2, were also evaluated. Granular sucrose induced decrease on the numbers of galls and eggs masses per root system as well as on juveniles in the soil. For sucrose solution assay, the best results for reproductive reduction were obtained with 300g of granular sucrose per liter of soil, applied at seven days intervals, associated with elephant-grass mulch.

Débora Cristina, Santiago; Martin, Homechin; Ricardo, Montalvan; Alaide Aparecida, Krzyzanowski.

2005-11-01

153

Effects of site-specific application of aldicarb on cotton in a meloidogyne incognita-infested field.  

Science.gov (United States)

Cotton farmers in Missouri commonly apply a single rate of aldicarb throughout the field at planting to protect their crop from Meloidogyne incognita, even though these nematodes are spatially aggregated. Our purpose was to determine the effect of site-specific application of aldicarb on cotton production in a field infested with these nematodes in 1997 and 1998. Cotton yields were collected from sites not treated with aldicarb (control), sites receiving aldicarb at the standard recommended rate of 0.58 kg a.i./ha, and sites receiving specific aldicarb rates based on the soil population densities of second-stage infective juveniles of root-knot nematode. Yields for the standard rate and site-specific rate treatments were similar and greater (P ? 0.05) than the control treatment. Less aldicarb was used for the site-specific than the uniform-rate treatment each year-46% less in 1997 and 61% less in 1998. Costs associated with the site-specific treatment were very high compared with the uniform-rate treatment due to a greater number of soil samples analyzed for nematodes. Site-specific application of aldicarb for root-knot nematode management in cotton may pose fewer environmental risks than the uniform-rate application of aldicarb. PMID:19265917

Wrather, J A; Stevens, W E; Kirkpatrick, T L; Kitchen, N R

2002-06-01

154

Histological mechanisms of the resistance conferred by the Ma gene against Meloidogyne incognita in Prunus spp.  

Science.gov (United States)

The Ma gene from Myrobalan plum is a TNL gene that confers a high-level resistance to all root-knot nematodes of major economic importance, including Meloidogyne incognita, M. javanica, M. arenaria, and M. enterolobii. The nematode behavior in the roots and the corresponding histological mechanisms of the Ma resistance to M. incognita in the resistant (R) accessions of the plum 'P.2175' and the interspecific hybrid P.2175×almond-peach '35', carrying the Ma1 allele (Ma1/ma), were characterized in comparison with the susceptible (S) accessions in the plum 'P.2032' and the interspecific hybrid P.2175×almond-peach '253' (ma/ma). Second-stage juveniles (J2s) were inoculated in micropropagated plantlets grown in soil substrate under controlled conditions at 25°C. Nematodes penetrated both R and S plants preferentially along the apical zone or close to the young lateral buds and moved via similar routes. Then they migrated into the cortex downward in the direction of the apex and turned up in the meristematic apical region to colonize the differentiating stele. In R accessions, motile J2s neither swelled nor developed into J3s, and initiation of feeding sites was never observed. This complete absence of gall symptoms is associated with cell necroses and corresponding hypersensitive-like reaction (HLR) phenotypes occurring either in the stele or in the meristematic apical region or in the cortex. Nematode attacks often disorganized the meristematic apical tissues of R accessions, which induced the development of subterminal lateral roots replacing primary terminal apices and, thus, provided an active resistance reaction to HLR damage. PMID:21446787

Khallouk, Samira; Voisin, Roger; Van Ghelder, Cyril; Engler, Gilbert; Amiri, Saïd; Esmenjaud, Daniel

2011-08-01

155

Effect of Simultaneous Water Deficit Stress and Meloidogyne incognita Infection on Cotton Yield and Fiber Quality.  

Science.gov (United States)

Both water deficit stress and Meloidogyne incognita infection can reduce cotton growth and yield, and drought can affect fiber quality, but the effect of nematodes on fiber quality is not well documented. To determine whether nematode parasitism affects fiber quality and whether the combined effects of nematode and drought stress on yield and quality are additive (independent effects), synergistic, or antagonistic, we conducted a study for 7 yr in a field infested with M. incognita. A split-plot design was used with the main plot factor as one of three irrigation treatments (low [nonirrigated], moderate irrigation, and high irrigation [water-replete]) and the subplot factor as 0 or 56 l/ha 1,3-dichloropropene. We prevented water deficit stress in plots designated as water-replete by supplementing rainfall with irrigation. Plots receiving moderate irrigation received half the water applied to the water-replete treatment. The severity of root galling was greater in nonfumigated plots and in plots receiving the least irrigation, but the amount of irrigation did not influence the effect of fumigation on root galling (no irrigation × fumigation interaction). The weights of lint and seed harvested were reduced in nonfumigated plots and also decreased as the level of irrigation decreased, but fumigation did not influence the effect of irrigation. Nematodes affected fiber quality by increasing micronaire readings but typically had little or no effect on percent lint, fiber length (measured by HVI), uniformity, strength, elongation, length (based on weight or number measured by AFIS), upper quartile length, or short fiber content (based on weight or number). Micronaire also was increased by water deficit stress, but the effects from nematodes and water stress were independent. We conclude that the detrimental effects caused to cotton yield and quality by nematode parasitism and water deficit stress are independent and therefore additive. PMID:24987162

Davis, R F; Earl, H J; Timper, P

2014-06-01

156

GAMMA IRRADIATION OF SUGAR BEET SEEDS INDUCED PLANT RESISTANCE TO ROOT-KNOT NEMATODE MELOIDOGYNE INCOGNITA  

International Nuclear Information System (INIS)

The main objective of this study was to investigate the effect of irradiation of sugar beet seeds on the plant resistance to root-knot nematode Meloidogyne incognita infection in addition to some morphological parameters, biochemical components and root technological characters. Relative to control (non-irradiated seeds), the obtained data showed that, all doses except 10 Gy significantly increased root length of un inoculated plants and the most effective dose was 200 Gy. All doses significantly decreased root diameter except 50 and 100 Gy. The 10 and 400 Gy significantly reduced root fresh weight while 50, 100 and 200 Gy caused non-significant increase. All doses significantly increased root fresh weight/dry weight than control. There was non-significant effect on the morphological parameters of the plants germinated from gamma irradiated seeds and inoculated with Meloidogyne incognita. Total chlorophyll of seed irradiated and un inoculated plants were significantly reduced by all doses except 200 Gy. All doses of gamma radiation caused non-significant decrease in the total chlorophyll of the infected plants. In un inoculated plants, a significant reduction in the total phenol was occurred due to all doses of gamma radiation. In contrast, in inoculated plants, 10 and 25 Gy caused significant reduction in the total phenol while 50 and 400 Gy caused significant increase in the total phenol.Significant increase in sucrose % was observed due to 10 Gy in the un inoculate observed due to 10 Gy in the un inoculated plants. The 400 Gy caused significant decrease while other doses caused non-significant decrease in the sucrose %. In the inoculated plants, 50, 100 and 400 Gy caused significant increase in sucrose %. All doses significantly increased total soluble salts percent (TSS %) of either inoculated or un inoculated plants. Purity % was increased by all doses in the inoculated plants.The number of galls and egg masses were reduced gradually by increasing gamma doses and 100 Gy caused the highest reduction 89.5 % and 94.7 % for galls and egg masses, respectively

157

Inconsistency of the biological control of Meloidogyne incognita race 2 in melon by endophytic bacteria Inconsistência do controle biológico de Meloidogyne incognita raça 2 em meloeiro por bactérias endofíticas  

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Full Text Available We obtained 61 rhizobacterium isolates from rhizosphere soil samples collected in melon commercial fields located in Mossoró, Rio Grande do Norte State, Brazil. These isolates, along with 56 endophytic bacteria from the Collection of Cultures of the Plant Bacteriology Laboratory of the Universidade Federal Rural de Pernambuco, were tested for controlling Meloidogyne incognita race 2 in melon. To infest the soil with nematodes, 1000 eggs of Meloidogyne incognita race 2 per plant were placed in pots where seedlings of the yellow-type melon, cultivar AF 682, were growing for 10 days. Two days before, 20 mL of bacterial suspension (0.7 OD570nm were poured into each pot. After 60 days, fresh root biomass, gall index, egg mass, and the nematode reproduction factor were assessed. Among the 117 isolates screened, the endophytic Bacillus ENM7, ENM10, and ENM51 were selected because they significantly reduced egg mass and/or gall index. However, when tested again, separately and in mixtures, these isolates nor confirmed their efficiency in vivo, neither affected juvenile emergence in vitro. These results give evidence on the inconsistency of using endophytic-bacteria in the control of M. incognita race 2 in melon.A partir de amostras de solo coletadas em plantios comerciais de meloeiro, situados em Mossoró-RN, foram obtidos 61 isolados de rizobactérias que, juntamente com outros 56 isolados endofíticos pertencentes à Coleção de Culturas do Laboratório de Fitobacteriologia da Universidade Federal Rural de Pernambuco, foram avaliados para o controle de Meloidogyne incognita raça 2 em melão. Plantas de meloeiro Amarelo, cultivar AF 682, com dez dias de idade tiveram o solo infestado com 1000 ovos de M. incognita raça 2 por planta. Dois dias antes, foram depositados em cada vaso 20 mL da suspensão bacteriana (DO570nm = 0,7. Decorridos 60 dias, foram determinados a biomassa fresca das raízes, os índices de galhas e de massa de ovos e o fator de reprodução do nematóide. Dos 117 isolados avaliados, foram selecionados inicialmente os isolados endofíticos ENM7, ENM10 e ENM51, todos pertencentes ao gênero Bacillus, que reduziram significativamente a massa de ovos e/ou o índice de galhas. Contudo, quando testados novamente, separadamente ou em misturas, esses isolados não mantiveram a eficiência na redução dessas variáveis e, in vitro, não afetaram a eclosão dos juvenis. Os resultados obtidos evidenciam a inconstância da ação das bactérias endofíticas no controle de M. incognita raça 2 em meloeiro.

Jeane E de Medeiros

2009-09-01

158

Evaluation of NemX, a New Cultivar of Cotton with High Resistance to Meloidogyne incognita.  

Science.gov (United States)

The level of resistance to root-knot nematode, Meloidogyne incognita, in NemX, a new cultivar of the Acala-type upland cotton, was evaluated in relation to four resistant breeding lines (N6072, N8577, N901, and N903) and four susceptible cultivars (Maxxa, SJ2, Royale, and Prema). In growth pouch tests, an average of only 4 nematode egg masses was produced on roots of NemX or the resistant lines, compared to a significantly higher average of 21 on the susceptible cultivars. In pot tests, the nematode reproduction factor (RF = Pf/Pi) in NemX and the resistant lines averaged 0.7, compared to a significantly higher average of 10 on the susceptible cultivars. Root galling in NemX or other resistant cotton averaged 15%, compared to 74% on the susceptible cultivars, in either pot or field tests. In plots with low levels of nematode infestation (Pi lint yield of NemX averaged 1,370 kg/ha and was less than the yield of susceptible Maxxa (1,450 k g /h a ). However, in plots with medium or high levels of nematode infestation (Pi = 151-300 or >300 J2/500 g soil, respectively), yields of NemX decreased only slightly and averaged 1,300 or 1,050 kg/ha, respectively, whereas yields of Maxxa were severely reduced to 590 or 503 kg/ha, respectively. Fusarium wih symptoms were observed on both NemX and Maxxa, and percent occurrence increased with increasing preplant nematode density. In plots with the highest nematode densities, 22% of NemX and 65% of Maxxa plants were wilted. NemX was highly effective against five M. incognita isolates and moderately effective against a sixth isolate that had been exposed to resistant cotton over several seasons. These results showed that NemX is as resistant to M. incognita as the four breeding lines, and much more resistant than the tested susceptible cultivars of cotton. PMID:19274190

Ogallo, J L; Goodell, P B; Eckert, J; Roberts, P A

1997-12-01

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COMPORTAMIENTO DE MATERIALES DE LOS GÉNEROS Carica Y Vasconcellea FRENTE A Erwinia papayae, Meloidogyne incognita Y Rotylenchulus reniformis / REACTION OF THE GENERA Carica AND Vasconcellea MATERIALS TO Erwinia papayae, Meloidogyne incognita AND Rotylenchulus reniformis  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish La bacteriosis del cancro y el ataque de los nematodos constituyen graves obstáculos en la extensión del cultivo de la papaya (Carica papaya L.). El objetivo principal de este trabajo fue la selección de genotipos tanto comerciales como silvestres resistentes a los patógenos mencionados. Para la eva [...] luación del comportamiento ante la bacteria del cancro causada por Erwinia papayae, se seleccionaron once accesiones de C. papaya, Vasconcellea goudotiana y V. cauliflora y se inocularon 10 plantas de cada genotipo con una suspensión bacteriana de concentración de 10(8) UFC.mL-1. La inoculación se realizó produciendo heridas en los tallos de las plantas sanas. Los testigos se trataron de igual forma con agua destilada estéril. Para la evaluación de la resistencia a nematodos se realizaron dos experimentos; en el primero se utilizaron materiales de C. papaya y V. goudotiana, los cuales se inocularon con una población mixta de Meloidogyne incognita raza 1 y Rotylenchulus reniformis con 2000 huevos+juveniles.1000 cm-3 en suelo-arena estéril. Para el segundo experimento se usaron, además de los materiales mencionados, V. cauliflora, V. cundinamarcensis, V. microcarpa var. microcarpa, V. microcarpa var. pilifera, inoculados sólo con M. incognita raza 1 con 2500 huevos+juveniles.1000 cm-3. A las 12 semanas se calculó la población final y se midieron las siguientes variables: peso aéreo y radical fresco y seco. Los resultados del comportamiento de los genotipos frente a la bacteria determinó que V. goudotiana y V. cauliflora no se enfermaron, no así el género Carica, donde todas las plantas resultaron susceptibles, coincidiendo con la evaluación de nematodos, donde todas las accesiones de C. papaya y V. goudotiana fueron susceptibles y no tolerante al ataque de la población mixta de M. incognita raza 1 y R. reniformis, por afectarse las variables agronómicas evaluadas; mientras que la mayoría de los materiales de V. cundinamarcencis y V. microcarpa resultaron resistentes al ataque de M. incognita raza 1. Estos resultados permiten la obtención de genes de resistencias en los materiales silvestres, los cuales podrían ser incorporados a los genotipos mejorados o comerciales, y permitiría un mejor manejo de los patógenos mencionados, que resultan limitantes severos en el cultivo de papaya en Venezuela. Abstract in english The bacterial canker and the attack of nematodes are serious obstacles to the extension of Carica papaya L. crop. The main objective of this work was the selection of both commercial and wild genotypes resistant to the above mentioned pathogens. To assess the response to the bacterial canker caused [...] by Erwinia papayae, eleven accesions of C. papaya, Vasconcellea goudotiana y V. cauliflora were selected and ten plants of each genotype were inoculated with a bacterial suspension with a concentration of 10(8) CFU.mL-1 . The plants were inoculated by wounds on the stems of the healthy plants. The controls were similarly treated but with sterile distilled water. Two trials were carried out to evaluate the resistance to nematodes. In the first trial, materials of C. papaya and V. goudotiana were inoculated with a mixed population of Meloidogyne incognita race 1 and Rotylenchulus reniformis, with 2000 eggs+juveniles. 1000 cm-3 in sterile soil-sand. In the second trial, V. cauliflora, V. cundinamarcensis, V. microcarpa var. microcarpa and V. microcarpa var. pilifera, in addition to the genotypes previously used, were inoculated only with M. incognita race 1, with 2500 eggs+juvenils.1000 cm-3. After 12 weeks, the final population was calculated and the fresh and dried weights of the aerial parts and roots were determined. The results of the reaction of the genotypes towards the bacterium determined that V. goudotiana and V. cauliflora did not get the disease, what differed from the Carica genus, where all the plants resulted susceptible, a result that was similar to the evaluation to nematodes, where all the genotypes

Anna, Maselli; Ligia Carolina, Rosales; Yolanda, Guevara; Zoraida, Suárez H.

2010-12-01

160

Tolerancia de 26 colectas de tomates nativos de México al nematodo Meloidogyne incognita (Kofoid y White) Chitwood / Tolerance of 26 native tomato collections from Mexico to nematode Meloidogyne incognita (Kofoid and White) Chitwood  

Scientific Electronic Library Online (English)

Full Text Available SciELO Mexico | Language: Spanish Abstract in spanish Se determinó la tolerancia de 26 colectas de tomates nativos de México a Meloidogyne incongnita (Kofoid y White) Chitwood, con el fin de identificar aquellas con potencial para su empleo en el mejoramiento genético o como portainjertos. Para ello, plantas de 30 días de edad fueron establecidas en hi [...] droponia bajo invernadero. Diez días después del trasplante (ddt) fue aplicada al sustrato una solución con 100,000 huevecillos-larva por planta. Se registraron caracteres de la parte aérea de plantas y a los 210 ddt se cuantificó el desarrollo de poblaciones de nematodos en raíces. M. incognita disminuyó el diámetro de frutos y el porte de planta (altura al primer racimo, peso seco de tallo y número de nudos), e incrementó el número de frutos y flores. Además, redujo la longitud de raíces y aumentó el volumen de éstas por la formación de nódulos. Mediante análisis multivariados (agrupamiento y discriminante) se definieron cinco grupos de colectas en función de la cantidad de agallas pequeñas y grandes, así como el total de éstas (82% de variación) y por la cantidad de larvas en raíz y huevecillos en sustrato (13% de variación). Se identificaron tres colectas tolerantes con bajos índices de agallas y menor presencia de huevecillos-larva en raíz y en sustrato. Ocho colectas fueron moderadamente tolerantes; nueve, moderadamente susceptibles, y seis, susceptibles. No se detectaron asociaciones entre orígenes de colectas o forma de fruto con respecto a la tolerancia al nematodo. Abstract in english The tolerance of 26 native tomato collections from Mexico to Meloidogyne incongnita (Kofoid and White) Chitwood was studied to identify those with potential for use in breeding or as rootstock. To do this, 30-day-old plants were established in a hydroponic system under greenhouse conditions. A solut [...] ion with 100,000 eggs-larvae per plant was applied to the substrate 10 days after transplantation (dat). Characters of the above-ground part of the plants were recorded and at 210 dat the development of nematode populations in roots was quantified. Meloidogyne incognita reduced fruit diameter and plant size (first truss height, stem dry weight, and node number), and increased the number of fruits and flowers. Additionally, it reduced root length and increased root volume due to nodule formation. By means of multivariate analysis (cluster and discriminant), five collection groups were defined based on the number of small and large galls, as well as total galls (82 % variation), and by the number of larvae in roots and eggs in the substrate (13 % variation). Three tolerant collections with low gall indices and a lower number of eggs-larvae in the roots and substrate were identified. Eight collections were moderately tolerant, nine moderately susceptible and six susceptible. No associations were detected between collection origins or fruit shape and tolerance to nematode.

Raquel, Cervantes-Moreno; Juan Enrique, Rodríguez-Pérez; Calixto, Carrillo Fonseca; Jaime, Sahagún-Castellanos; Eduardo, Rodríguez-Guzmán.

2014-04-01

161

Nematicidal activity of mint aqueous extracts against the root-knot nematode Meloidogyne incognita.  

Science.gov (United States)

The nematicidal activity and chemical characterization of aqueous extracts and essential oils of three mint species, namely, Mentha × piperita , Mentha spicata , and Mentha pulegium , were investigated. The phytochemical analysis of the essential oils was performed by means of GC-MS, whereas the aqueous extracts were analyzed by LC-MS. The most abundant terpenes were isomenthone, menthone, menthol, pulegone, and carvone, and the water extracts yielded mainly chlorogenic acid, salvianolic acid B, luteolin-7-O-rutinoside, and rosmarinic acid. The water extracts exhibited significant nematicidal activity against Meloidogyne incognita , and the EC50/72h values were calculated at 1005, 745, and 300 mg/L for M. × piperita, M. pulegium, and M. spicata, respectively. Only the essential oil from M. spicata showed a nematicidal activity with an EC50/72h of 358 mg/L. Interestingly, menthofuran and carvone showed EC50/48h values of 127 and 730 mg/L, respectively. On the other hand, salicylic acid, isolated in the aqueous extracts, exhibited EC50 values at 24 and 48 h of 298 ± 92 and 288 ± 79 mg/L, respectively. PMID:24050256

Caboni, Pierluigi; Saba, Marco; Tocco, Graziella; Casu, Laura; Murgia, Antonio; Maxia, Andrea; Menkissoglu-Spiroudi, Urania; Ntalli, Nikoletta

2013-10-16

162

Nematicidal activity of allylisothiocyanate from horseradish (Armoracia rusticana) roots against Meloidogyne incognita.  

Science.gov (United States)

In recent years, there has been a great development in the search for new natural pesticides for crop protection aiming a partial or total replacement of currently used chemical nematicides. Glucosinolate breakdown products are volatile and are therefore good candidates for nematodes fumigants. In this article, the methanol-aqueous extract (1:1, w/v) of horseradish (Armoracia rusticana) fresh roots (MAH) was in vitro tested for nematicidal activity against second stage (J2) Meloidogyne incognita. The EC50 of MAH after 3 days of J2 immersion in test solutions was 251 ± 46 mg/L. The chemical composition analysis of the extract carried out by the GC-MS technique showed that allylisothicyanate was the most abundant compound. This pure compound induced J2 paralysis with an EC50 of 52.6 ± 45.6 and 6.6 ± 3.4 mg/L after 1 h and 3 days of incubation. The use of LC-MS/MS showed for the first time that horseradish root is rich in polyphenols. The study of isothiocyanate degradation in soil showed that allylisothiocyanate was the most quickly degradable compound (half-life <10 min), whereas no significant differences in half-life time were noted between degradation in regular and autoclaved soil. PMID:23627288

Aissani, Nadhem; Tedeschi, Paola; Maietti, Annalisa; Brandolini, Vincenzo; Garau, Vincenzo Luigi; Caboni, Pierluigi

2013-05-22

163

Isolation of Nematicidal Triterpenoid Saponins from Pulsatilla koreana Root and Their Activities against Meloidogyne incognita  

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Full Text Available Pulsatilla koreana, a species endemic to Korea, is an important herb used in traditional medicine to treat amoebic dysentery and malaria. In the present study, 23 oleanane-type triterpenoid saponins 1–23 and eight lupane-type triterpenoid saponins 24–31 were isolated from the roots of P. koreana. Their structures were elucidated on the basis of spectroscopic data. The methanol extract and isolated compounds were next assessed for nematicidal activity against the root-knot nematode (Meloidogyne incognita. The methanol extract showed strong nematicidal activity after 48 h, with a LC50 value of 92.8 ?g/mL. Compounds 2, 5, 9, 20, and 21 showed significant effects, with LC50 values ranging from 70.1 to 94.7 ?g/mL after 48 h. These results suggest that triterpenoid saponins from P. koreana should be explored as potential natural nematicides for developing new agents to control root-knot nematode disease

Byung Soo Han

2013-05-01

164

Influence of Infection of Cotton by Rotylenchulus Reniformis and Meloidogyne Incognita on the Production of Enzymes Involved in Systemic Acquired Resistance  

OpenAIRE

Systemic acquired resistance (SAR), which results in enhanced defense mechanisms in plants, can be elicited by virulent and avirulent strains of pathogens including nematodes. Recent studies of nematode reproduction strongly suggest that Meloidogyne incognita and Rotylenchulus reniformis induce SAR in cotton, but biochemical evidence of SAR was lacking. Our objective was to determine whether infection of cotton by M. incognita and R. reniformis increases the levels of P-peroxidase, G-peroxida...

Aryal, Sudarshan K.; Davis, Richard F.; Stevenson, Katherine L.; Timper, Patricia; Ji, Pingsheng

2011-01-01

165

Nematocidal Flavone-C-Glycosides against the Root-Knot Nematode (Meloidogyne incognita from Arisaema erubescens Tubers  

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Full Text Available A screening of several Chinese medicinal herbs for nematicidal properties showed that Arisaema erubescens (Wall. Schott tubers possessed significant nematicidal activity against the root-knot nematode (Meloidogyne incognita. From the ethanol extract, two nematicidal flavone-C-glycosides were isolated by bioassay-guided fractionation. The compounds were identified as schaftoside and isoschaftoside on the basis of their phytochemical and spectral data. Schaftoside and isoschaftoside possessed strong nematicidal activity against M. incognita (LC50 = 114.66 ?g/mL and 323.09 ?g/mL, respectively while the crude extract of A. erubescens exhibited nematicidal activity against the root-knot nematode with a LC50 value of 258.11 ?g/mL.

Zhi Long Liu

2011-06-01

166

Genome-wide survey and analysis of microsatellites in nematodes, with a focus on the plant-parasitic species Meloidogyne incognita  

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Full Text Available Abstract Background Microsatellites are the most popular source of molecular markers for studying population genetic variation in eukaryotes. However, few data are currently available about their genomic distribution and abundance across the phylum Nematoda. The recent completion of the genomes of several nematode species, including Meloidogyne incognita, a major agricultural pest worldwide, now opens the way for a comparative survey and analysis of microsatellites in these organisms. Results Using MsatFinder, the total numbers of 1-6 bp perfect microsatellites detected in the complete genomes of five nematode species (Brugia malayi, Caenorhabditis elegans, M. hapla, M. incognita, Pristionchus pacificus ranged from 2,842 to 61,547, and covered from 0.09 to 1.20% of the nematode genomes. Under our search criteria, the most common repeat motifs for each length class varied according to the different nematode species considered, with no obvious relation to the AT-richness of their genomes. Overall, (ATn, (AGn and (CTn were the three most frequent dinucleotide microsatellite motifs found in the five genomes considered. Except for two motifs in P. pacificus, all the most frequent trinucleotide motifs were AT-rich, with (AATn and (ATTn being the only common to the five nematode species. A particular attention was paid to the microsatellite content of the plant-parasitic species M. incognita. In this species, a repertoire of 4,880 microsatellite loci was identified, from which 2,183 appeared suitable to design markers for population genetic studies. Interestingly, 1,094 microsatellites were identified in 801 predicted protein-coding regions, 99% of them being trinucleotides. When compared against the InterPro domain database, 497 of these CDS were successfully annotated, and further assigned to Gene Ontology terms. Conclusions Contrasted patterns of microsatellite abundance and diversity were characterized in five nematode genomes, even in the case of two closely related Meloidogyne species. 2,245 di- to hexanucleotide loci were identified in the genome of M. incognita, providing adequate material for the future development of a wide range of microsatellite markers in this major plant parasite.

Guillemaud Thomas

2010-10-01

167

Efecto del follaje de Tagetes minuta sobre la nodulación radicular de Meloidogyne incognita en Capsicum annuum, en invernadero / Effect of the foliage of Tagetes minuta on Meloidogyne incognita root-galling on Capsicum annuum in a greenhouse  

Scientific Electronic Library Online (English)

Full Text Available Se investigó el efecto del follaje del "huacatay" Tagetes minuta sobre la nodulación radicular producida por el nematodo Meloidogyne incognita que parasita el "pimiento páprika" Capsicum annuum cultivado en invernadero, con la finalidad de obtener una alternativa de control de este nematodo. Se util [...] izaron tres grupos experimentales y un testigo, con 12 macetas cada uno, las cuales contenían suelo y arena estériles (1:1). A este substrato se adicionó el follaje de T. minuta al 20, 35 y 50% (v/v) según grupo experimental, y el testigo no recibió esta enmienda. En cada maceta se sembró una plántula de C. annuum, y a la semana postsiembra se inoculó 5000 huevos de M. incognita. A las ocho semanas, se evaluaron los nódulos en sus raíces. Todas las plantas presentaron nódulos; aunque, en aquellas de los grupos experimentales el número de éstos fue menor que en las plantas testigo, con diferencia estadística significativa (p 0,05). Se concluye que el follaje de T. minuta adicionado como enmienda orgánica al 20, 35 y 50% al suelo de cultivo de plantas de C. annuum limita la nodulación radicular ocasionada por M. incognita. Lo cual sugiere su uso potencial en el control de este nematodo Abstract in english The effect of the foliage of Tagetes minuta "huacatay" on Meloidogyne incognita root-galling on Capsicum annuum "paprika pepper" cultured in a greenhouse was researched, to obtain a control strategy for this nematode. Three experimental groups and one control with 12 pots each were used, which conta [...] ined sterilized soil and sand (1:1). To this substrate was added cut foliage of T. minuta at 20, 35 and 50% (v/v) according to the experimental group, and the control group remained without this amendment. In each pot a seedling of C. annuum was sown, and one week post-seeding was inoculated with 5000 eggs of M. incognita. Eight weeks later the root galling was evaluated. All the plants had root galling; although the number of galls in plants of the experimental groups was less than those in the control group with statistical significant difference (p 0.05). It is concluded that the foliage of T. minuta added as organic amendment at 20, 35 and 50% to the culture soil for C. annuum plants limits the M. incognita root galling. That suggests its potential use in the control of this nematode

Santos Nélida, Murga-Gutiérrez; Juan Carlos, Alvarado-Ibáñez; Nora Yessenia, Vera-Obando.

2012-12-01

168

Yield Response and Injury Levels of Meloidogyne incognita and M. javanica on the Susceptible Tobacco 'McNair 944'  

OpenAIRE

The effects of Meloidogyne incognita and M. javanica on a susceptible tobacco (Nicotiana tabacum L.) cv. McNair 944 were investigated in field microplots during 1978 and 1979. Three initial inoculum levels—4, 16, and 64 nematode eggs and/or second-stage larvae per 100 cm³ of soil—were used for each nematode species. Data obtained from the experiments included plant yield and the amount of reproduction of the two nematode species. At comparative inoculum levels, M. javanica was more aggre...

Arens, M. L.; Rich, J. R.

1981-01-01

169

Influence of Meloidogyne incognita on Fusarium Wilt of Tomato at or below the Minimum Temperature for Wilt Development  

OpenAIRE

'Bonny Best' tomato plants were grown at 16, 21, or 24 C for 28 d in soil infested with either of two isolates of Fusarium oxysporum f. sp. lycopersici race 1 and Meloidogyne incognita. Significant levels of fusarium wilt occurred at all temperatures including 16 C, which has not been reported previously. One Fusarium isolate resulted in the highest levels of disease incidence at 21 and 24 C in the presence of root-knot nematodes, and at 24 C when the nematodes were not present. At 16 C there...

Morrell, J. J.; Bloom, J. R.

1981-01-01

170

Screening and Histopathological Characterization of Korean Carrot Lines for Resistance to the Root-Knot Nematode Meloidogyne incognita  

OpenAIRE

In total, 170 carrot lines developed in Korea were screened for resistance to Meloidogyne incognita race 1 to select parental genetic resources useful for the development of nematode-resistant carrot cultivars. Using the gall index (GI), gall formation was examined on carrot roots inoculated with approximately 1,000 second-stage juveniles of the nematode 7 weeks after inoculation. Sixty-one carrot lines were resistant (GI ? 1.0), while the other 109 were susceptible (GI > 1.0) with coeffici...

Seo, Yunhee; Park, Jiyeong; Kim, Yong Su; Park, Yong; Kim, Young Ho

2014-01-01

171

Screenhouse Assessment of Reaction of Fluted Pumpkin, Telfairia Occidentalis Hook F. to Root-Knot Nematode Meloidogyne Incognita  

OpenAIRE

Screenhouse studies were carried out between April – June and July – September, 2004 at the vegetable researchunit of National HorticulturalResearch Institute (NIHORT), Ibadan,Nigeria to investigate the reaction of five linesof Telfairia occidentalis (EN2000-4, EN2000-6, EN2000-10, EN2000-11, EN2000-13) to different populationlevels (0, 5000 and 10 000 eggs) of Meloidogyne incognita race 2. Seeds from five different matured pods ofTelfairia lines were planted on moist sawdust medium. They...

Izuogu, N. B.; Oyedunmade, E. E. A.; Babatola, J. O.

2010-01-01

172

Reação de clones de batata-doce à Meloidogyne incognita raças 1 e 4 e estimativa de parâmetros genéticos / Reaction of sweet potato clones to Meloidogyne incognita races 1 and 4, and estimation of genetic parameters  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese O objetivo deste trabalho foi selecionar clones de batata-doce resistentes às raças 1 e 4 de Meloidogyne incognita, além de avaliar a eficiência do método de seleção empregado, pela estimativa de parâmetros genéticos. Foram avaliados 21 acessos do jardim clonal da Universidade de Brasília e três cul [...] tivares de batata-doce (Brazlândia Branca, Brazlândia Roxa e Amarela). O experimento foi conduzido em casa de vegetação, com delineamento de blocos casualizados em arranjo simples, com 24 tratamentos, quatro repetições e três plantas por parcela. A inoculação do patógeno foi feita trinta dias após o plantio das ramas e, após noventa dias, foi feita a contagem do número médio de massas de ovos encontradas nas raízes das plantas inoculadas. Foram considerados resistentes os clones que apresentaram em média 0 a 1,9 massas de ovos por sistema radicular, moderadamente resistentes aqueles que apresentaram de 2,0 a 2,9 massas de ovos, moderadamente suscetíveis os que obtiveram número médio de massas de ovos variando entre 3,0 e 3,9, e suscetíveis aqueles com 4,0 a 5,0 massas de ovos por sistema radicular. Dos 24 materiais analisados, nove (37,5%) foram classificados como resistentes à raça 1 de M. incognita e 16 (66,67%) foram classificados como resistentes à M. incognita raça 4. Os clones 1200, 1210, 1199, 1229, 1230, 1202, 1231, 1216 e 1209 apresentaram resistência tanto à raça 1 quanto à raça 4 de M. incognita. A resistência das plantas a essas duas populações de nematoides testadas apresentou alta herdabilidade, e a relação entre os coeficientes de variação genético e ambiental do experimento para resistência à raça 4 de M. incognita apresentou-se mais baixa que aquela encontrada no outro experimento para resistência à raça 1. Abstract in english The objective of this work was to select sweet potato resistant clones to the races 1 and 4 of Meloidogyne incognita, and measure the efficiency of the selection method used, by means of the estimation of genetic and environmental coefficients of variation, and broad-sense heritabilities. We evaluat [...] ed 21 accessions of the clonal garden of the Universidade de Brasilia, and three cultivars of sweet potato (Brazlândia Branca, Brazlândia Roxa and Amarela). The experiment was carried out in a greenhouse with a randomized block design in simple arrangement, with 24 treatments, four replications and three plants per plot. The inoculation of the pathogen was made thirty days after planting the slips and, after ninety days, the counting of the average number of egg masses of the infected plants was completed. Clones were considered resistant when presented a number of egg masses per root system from 0 to 1.9, moderately resistant 2.0 to 2.9, moderately susceptible 3.0 to 3.9, and, susceptible 4.0 to 5.0. From 24 clones analyzed, nine (37.5%) were classified as resistant to the race 1 of M. incognita, and 16 (66.67%) were classified as resistant to the race 4 of M. incognita. The clones 1200, 1210, 1199, 1229, 1230, 1202, 1231, 1216 and 1209 were resistant to the two races tested of M. incognita. The resistance of the plants to these two races of root-knot nematodes presented high heritability, and the relationship between the coefficients of genetic and environmental variation of the experiment to resistance to race 4 of M. incognita was shorter than that one found in the another experiment, that aimed resistance to the race 1.

Danielle C, Kalkmann; José R, Peixoto; Daiane da S, Nóbrega.

2013-06-01

173

Preliminary evaluation of meloidogyne incognita race 3 reproduction on garden pea cultivars in Brazil/ Avaliação preliminar da reprodução de Meloidogyne incognita raça 3 em cultivares de ervilha no Brasil  

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Full Text Available Thirteen garden pea cultivars, were assessed for the reproductive rate of the root-knot nematode Meloidogyne incognita race 3 under greenhouse conditions. Two-week old plants growing were inoculated with 5.000 eggs. The nematode reproduction data was determined 55 days later according to the three adopted evaluation criteria (root-gall and egg-mass indexes, reproduction factor, percentage of reduction of the reproduction factor in relation to the susceptible standard cultivar. The tested cultivars were rated as highly susceptible ('Trolly'. 'Jurema', susceptible ('Luiza'. 'Mini'. 'Asterix', 'Verde Temprana' or moderately susceptible ('Marina', 'Telephone'., 'Dileta'. 'Bolero', 'Flávia'. 'Viçosa', and 'Maria' hosts for the nematode.Avaliaram-se as taxas reprodutivas e caracterizaram-se as reações de 13 cut tiveres de ervilha em relação ao nematóide de galhas Meloidogyne incognita raça 3, em casa-de-vegetação. Plantas com duas semanas de idade, foram inoculadas com 5000 ovos do nematóide. As avaliações foram realizadas após 55 dias com base nos critérios - índices de galhas/índices de massas de ovos, fator de reprodução e porcentagem de redução do fator de reprodução. Duas cultivares foram consideradas hospedeiras altamente suscetíveis (‘Trolly’, ‘Jurema’, cinco suscetíveis ('Luíza', 'Mini', 'Asterix', 'Verde Temprana', 'Telefone' e seis moderadamente suscetíveis ('Marina'. 'Dileta', 'Boiero'. 'Flávia'. 'Viçosa', 'Maria'.

Luiz Carlos Camargo Barbosa Ferraz

2000-01-01

174

Nematicidal activity of 3,4-dihydroxybenzoic acid purified from Terminalia nigrovenulosa bark against Meloidogyne incognita.  

Science.gov (United States)

In this study, the 3,4-dihydroxybenzoic acid (3,4-DHBA) from Terminalia nigrovenulosa bark (TNB) was purified and its in vitro nematicidal activity was investigated against Meloidogyne incognita. The purification of 3,4-DHBA used a silica gel column and Sephadex LH-20 chromatography combined with thin-layer chromatography and high performance liquid chromatography. Structural identification of the 3,4-DHBA was conducted using (1)H nuclear magnetic resonance (NMR), (13)C NMR, and liquid chromatography time-of-flight mass spectrometry. Nematicidal activity bioassays revealed that 3,4-DHBA treatment resulted in 33.3, 47.5, 72.5 and 94.2% J2 mortality at 0.125, 0.25, 0.5 and 1.0 mg/ml, respectively after 12 h incubation. J2 mortality was increased significantly (P < 0.0001) with increasing incubation time in the range of 54.2-94.2% from 3 to 9 h after incubation with 3,4-DHBA (1.0 mg/ml), but with no significant difference observed where the incubation time was increased from 9 to 12 h. The 3,4-DHBA treatment resulted in 33.3, 65.0, 76.7 and 85.0% hatch inhibition at 0.125, 0.25, 0.5 and 1.0 mg/ml, respectively, 3 days after incubation. Changes in the shape of the eggs were determined after incubation for 1 day with a 3,4-DHBA concentration of 1.0 mg/ml. PMID:23603737

Nguyen, Dang-Minh-Chanh; Seo, Dong-Jun; Kim, Kil-Yong; Park, Ro-Dong; Kim, Dong-Hyun; Han, Yeon-Soo; Kim, Tae-Hwan; Jung, Woo-Jin

2013-01-01

175

Screenhouse Assessment of Reaction of Fluted Pumpkin, Telfairia Occidentalis Hook F. to Root-Knot Nematode Meloidogyne Incognita  

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Full Text Available Screenhouse studies were carried out between April – June and July – September, 2004 at the vegetable researchunit of National HorticulturalResearch Institute (NIHORT, Ibadan,Nigeria to investigate the reaction of five linesof Telfairia occidentalis (EN2000-4, EN2000-6, EN2000-10, EN2000-11, EN2000-13 to different populationlevels (0, 5000 and 10 000 eggs of Meloidogyne incognita race 2. Seeds from five different matured pods ofTelfairia lines were planted on moist sawdust medium. They were watered every two days until germination andtransplanting. Experimental layout was a completely randomized design and each treatment was replicated fivetimes. Nematode inoculation was done at one week after transplanting. The plants were watered every two daysand observation of vine length, vine girth and number of leaves commenced two weeks after transplanting (WATon bi weekly basis and lasted till the 10th week. From the 4th WAT, roots were assessed for the presence of eggsevery five days in view of determining the generation time in the various lines. Soil nematode population and rootgall indices were determined at the end of the trial.Results showed that there were significant differences between the Telfairia lines in the measured parametersirrespective of the inoculum levels. EN2000-4 performed significantly better than the other lines. EN2000-13which closely followed EN2000-4 with respect to vegetative growth, recorded significantly higher galling indexthan all the other lines. There were significant differences between the inoculum levels. Inoculum levels wereinversely proportional to growth parameters and directly proportional to gall indices in all the lines. Chloroticpatches were also observed on the leaves of plants inoculated with 10 000 eggs. The uninoculated (control plantsgave significantly better vegetative growth than their inoculated counterparts. The disparities in growth and yieldresponses indicate that there is genetic variability among the lines.

N. B. IZUOGU

2010-08-01

176

Virulence of Meloidogyne spp. and Induced Resistance in Grape Rootstocks  

OpenAIRE

Harmony grape rootstock displays resistance to several Meloidogyne spp. but that resistance is not durable in commercial vineyard settings. A 2-year experiment in a microplot setting revealed host specificities of two virulent populations of Meloidogyne arenaria and an avirulent population of Meloidogyne incognita. In a subsequent split-root experiment, the avirulent nematode population was demonstrated to induce resistance to the virulent nematode population. To quantify the level of resista...

Mckenry, Michael V.; Anwar, Safdar A.

2007-01-01

177

Mean Dosage Stimulation Range of Allelochemicals from Crude Extracts of Cucumis africanus Fruit for Improving Growth of Tomato Plant and Suppressing Meloidogyne incognita Numbers  

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Full Text Available Successful utilisation of allelochemicals in management of plant-parasitic nematodes depends on their degree of phytotoxicity. Conventional methods of determining phytotoxicity are tedious, with inconsistent results. Plants respond to increased dosages of allelochemicals in a density-dependent growth pattern, which allows the use of the Curve-fitting Allelochemical Response Data computer-based model to determine the mean dosage stimulation range of used allelochemicals. The CARD modelling was used to determine the stimulation range of fermented dried crude extracts of wild cucumber (Cucumis africanus fruit for improving growth of tomato (Solanum lycopersicon plants, each infested with 1500 eggs and juveniles of the southern root-knot (Meloidogyne incognita nematode. Dilutions at 0, 2, 4, 8, 16, 32 and 64% were applied weekly through irrigation system. At 56 days after treatment, CARD demonstrated density-dependent growth patterns as dosages increased. The mean dosage stimulation range of diluted fermented crude extracts, computed from CARD biological indices, was 2.64% dilution for tomato plant. Since at 2% dilution, the material reduced final nematode population density of M. incognita by 90%. The 2.64% was suitable for stimulation of tomato plant and suppression of nematode numbers.

Osvaldo Pelinganga

2012-11-01

178

Interactions between an arbuscular mycorrhizal fungus (Scutellospora heterogama) and the root-knot nematode (Meloidogyne incognita) on sweet passion fruit (Passiflora alata)  

Scientific Electronic Library Online (English)

Full Text Available O efeito da inoculação com Scutellospora heterogama (200 esporos/planta) em relação aos sintomas e reprodução de Meloidogyne incognita raça 1 (5000 ovos/planta) foi avaliado em plantas de maracujazeiro doce em dois experimentos em casa de vegetação. No primeiro experimento, inoculações com nematóide [...] e FMA foram simultâneas; no segundo, nematóides foram inoculados 120 dias após o estabelecimento da simbiose micorrízica. Após o 220º dia da inoculação do FMA o fungo estimulou o crescimento da planta nos dois experimentos. No solo desinfestado as mudas não inoculadas com S. heterogama mostraram intolerância ao parasitismo de M. incognita. A esporulação de S. heterogama foi negativamente afetada pela presença do nematóide. M. incognita não afetou o crescimento das mudas micorrizadas ou o desenvolvimento do FMA. O estabelecimento da micorriza antes do nematóide contribui para a redução da severidade dos sintomas e reprodução de M. incognita em solo desinfestado. Abstract in english The effects of inoculation of sweet passion fruit plants with the arbuscular mycorrhizal (AM) fungus Scutellospora heterogama on the symptoms produced by Meloidogyne incognita race 1 and its reproduction were evaluated in two greenhouse experiments. In the 1st, the M. incognita (5000 eggs/plant) and [...] S. heterogama (200 spores/plant) inoculations were simultaneous; in the 2nd, the nematodes were inoculated 120 days after the fungal inoculation. In both the experiments, 220 days after AM fungal inoculation, plant growth was stimulated by the fungus. In disinfested soil, control seedlings (without S. heterogama) were intolerant to parasitism of M. incognita, while the growth of mycorrhized seedlings was not affected. Sporulation of S. heterogama was negatively affected by the nematodes that did not impair the colonization. M. incognita did not affect mycorrhizal seedling growth. The establishment of mycorrhiza prior to the nematode infection contributed for the reduction of symptoms severity and reproduction of M. incognita in disinfested soil.

Érika Cristina Teixeira dos, Anjos; Uided Maaze Tiburcio, Cavalcante; Danielle Maria Correia, Gonçalves; Elvira Maria Regis, Pedrosa; Venézio Felipe dos, Santos; Leonor Costa, Maia.

2010-08-01

179

Efficacy evaluation of fungus Syncephalastrum racemosum and nematicide avermectin against the root-knot nematode Meloidogyne incognita on cucumber.  

Science.gov (United States)

The root-knot nematode (RKN) is one of the most damaging agricultural pests.Effective biological control is need for controlling this destructive pathogen in organic farming system. During October 2010 to 2011, the nematicidal effects of the Syncephalastrum racemosum fungus and the nematicide, avermectin, alone or combined were tested against the RKN (Meloidogyne incognita) on cucumber under pot and field condition in China. Under pot conditions, the application of S. racemosum alone or combined with avermectin significantly increased the plant vigor index by 31.4% and 10.9%, respectively compared to the M. incognita-inoculated control. However, treatment with avermectin alone did not significantly affect the plant vigor index. All treatments reduced the number of root galls and juvenile nematodes compared to the untreated control. Under greenhouse conditions, all treatments reduced the disease severity and enhanced fruit yield compared to the untreated control. Fewer nematodes infecting plant roots were observed after treatment with avermectin alone, S. racemosum alone or their combination compared to the M. incognita-inoculated control. Among all the treatments, application of avermectin or S. racemosum combined with avermectin was more effective than the S. racemosum treatment. Our results showed that application of S. racemosum combined with avermectin not only reduced the nematode number and plant disease severity but also enhanced plant vigor and yield. The results indicated that the combination of S. racemosum with avermectin could be an effective biological component in integrated management of RKN on cucumber. PMID:24586982

Huang, Wen-Kun; Sun, Jian-Hua; Cui, Jiang-Kuan; Wang, Gang-Feng; Kong, Ling-An; Peng, Huan; Chen, Shu-Long; Peng, De-Liang

2014-01-01

180

Efeito de manipueira sobre Meloidogyne incognita em ensaios in vitro e em tomateiros em casa de vegetação / Effect of manipueira on Meloidogyne incognita through in vitro and in vivo essays on tomatoes in greenhouse  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Objetivou-se estudar o efeito nematicida de manipueira no controle de Meloidogyne incognita. Testes in vitro foram divididos em dois ensaios inteiramente casualizados: 1. manipueira a 100%, 75%, 50% e 25% em 12 repetições; 2. manipueira a 15%, 10%, 8%, 6%, 4% e 2% em 5 repetições. O ensaio em vasos [...] seguiu o delineamento inteiramente casualisado com manipueira a 10%, 25% e 50% em 5 repetições. Para ambos os ensaios utilizou-se o tratamento somente água como testemunha positiva e Carbofuran (50 mg.L-1 de ingrediente ativo (i.a.) ou 2 g de produto comercial/vaso) como negativa. Para os ensaios in vitro foram avaliados nematóides vivos e mortos e número de galhas em plantas inoculadas. Para os ensaios em vaso foram avaliadas as variáveis altura de plantas, comprimento de raízes, número de galhas, número de ovos e fator de reprodução (FR). Os resultados in vitro demonstraram que os tratamentos com manipueira até 10% de diluição apresentaram 100% de controle. O ensaio com tomateiros previamente inoculados demonstrou que o tratamento manipueira 50% causou um melhor desenvolvimento da parte aérea das plantas de tomate. Os tratamentos manipueira a 10% e 25% foram mais efetivos no controle de M. incognita em vasos. Abstract in english The aim of this work was to study the nematicidal effect of manipueira on the control of Meloidogyne incognita. In vitro tests were split into two completely randomized assays: 1. manipueira 100%, 75%, 50% and 25% in 12 replications; 2. manipueira 15%, 10%, 8%, 6%, 4% and 2% in 5 replications. The p [...] ot assay followed a completely randomized design with the treatments manipueira 10%, 25% and 50% in 5 replications. For both assays the positive control was water and the negative control was the nematicide Carbofuran (50 mg.L-1 of active ingredient (a.i.) or 2 g of commercial product/pot). For in vitro assays the variables assessed were live or dead nematodes and number of galls on inoculated plants. For the pot assay the variables evaluated were plant height, root length, number of galls, number of eggs and reproduction factor (RF). The in vitro results indicated that only the manipueira treatments from 100% to 10% dilution showed maximum control. The pot assay demonstrated that the treatment manipueira 50% caused better development of tomato shoots than the others. However, manipueira 10% and 25% were more effective against of M. incognita in pots.

Érica G.C., Nasu; Ely, Pires; Heloísa M., Formentini; Cleber, Furlanetto.

2010-02-01

181

Efeito de manipueira sobre Meloidogyne incognita em ensaios in vitro e em tomateiros em casa de vegetação Effect of manipueira on Meloidogyne incognita through in vitro and in vivo essays on tomatoes in greenhouse  

Directory of Open Access Journals (Sweden)

Full Text Available Objetivou-se estudar o efeito nematicida de manipueira no controle de Meloidogyne incognita. Testes in vitro foram divididos em dois ensaios inteiramente casualizados: 1. manipueira a 100%, 75%, 50% e 25% em 12 repetições; 2. manipueira a 15%, 10%, 8%, 6%, 4% e 2% em 5 repetições. O ensaio em vasos seguiu o delineamento inteiramente casualisado com manipueira a 10%, 25% e 50% em 5 repetições. Para ambos os ensaios utilizou-se o tratamento somente água como testemunha positiva e Carbofuran (50 mg.L-1 de ingrediente ativo (i.a. ou 2 g de produto comercial/vaso como negativa. Para os ensaios in vitro foram avaliados nematóides vivos e mortos e número de galhas em plantas inoculadas. Para os ensaios em vaso foram avaliadas as variáveis altura de plantas, comprimento de raízes, número de galhas, número de ovos e fator de reprodução (FR. Os resultados in vitro demonstraram que os tratamentos com manipueira até 10% de diluição apresentaram 100% de controle. O ensaio com tomateiros previamente inoculados demonstrou que o tratamento manipueira 50% causou um melhor desenvolvimento da parte aérea das plantas de tomate. Os tratamentos manipueira a 10% e 25% foram mais efetivos no controle de M. incognita em vasos.The aim of this work was to study the nematicidal effect of manipueira on the control of Meloidogyne incognita. In vitro tests were split into two completely randomized assays: 1. manipueira 100%, 75%, 50% and 25% in 12 replications; 2. manipueira 15%, 10%, 8%, 6%, 4% and 2% in 5 replications. The pot assay followed a completely randomized design with the treatments manipueira 10%, 25% and 50% in 5 replications. For both assays the positive control was water and the negative control was the nematicide Carbofuran (50 mg.L-1 of active ingredient (a.i. or 2 g of commercial product/pot. For in vitro assays the variables assessed were live or dead nematodes and number of galls on inoculated plants. For the pot assay the variables evaluated were plant height, root length, number of galls, number of eggs and reproduction factor (RF. The in vitro results indicated that only the manipueira treatments from 100% to 10% dilution showed maximum control. The pot assay demonstrated that the treatment manipueira 50% caused better development of tomato shoots than the others. However, manipueira 10% and 25% were more effective against of M. incognita in pots.

Érica G.C. Nasu

2010-02-01

182

Preferential expression of a plant cystatin at nematode feeding sites confers resistance to Meloidogyne incognita and Globodera pallida.  

Science.gov (United States)

The expression patterns of three promoters preferentially active in the roots of Arabidopsis thaliana have been investigated in transgenic potato plants in response to plant parasitic nematode infection. Promoter regions from the three genes, TUB-1, ARSK1 and RPL16A were linked to the GUS reporter gene and histochemical staining was used to localize expression in potato roots in response to infection with both the potato cyst nematode, Globodera pallida and the root-knot nematode, Meloidogyne incognita. All three promoters directed GUS expression chiefly in root tissue and were strongly up-regulated in the galls induced by feeding M. incognita. Less activity was associated with the syncytial feeding cells of the cyst nematode, although the ARSK1 promoter was highly active in the syncytia of G. pallida infecting soil grown plants. Transgenic potato lines that expressed the cystatin OcIDeltaD86 under the control of the three promoters were evaluated for resistance against Globodera sp. in a field trial and against M. incognita in containment. Resistance to Globodera of 70 +/- 4% was achieved with the best line using the ARSK1 promoter with no associated yield penalty. The highest level of partial resistance achieved against M. incognita was 67 +/- 9% using the TUB-1 promoter. In both cases this was comparable to the level of resistance achieved using the constitutive cauliflower mosaic virus 35S (CaMV35S) promoter. The results establish the potential for limiting transgene expression in crop plants whilst maintaining efficacy of the nematode defence. PMID:17166138

Lilley, Catherine J; Urwin, Peter E; Johnston, Katherine A; Atkinson, Howard J

2004-01-01

183

Short interfering RNA-mediated gene silencing in Globodera pallida and Meloidogyne incognita infective stage juveniles.  

Science.gov (United States)

The analysis of gene function through RNA interference (RNAi)-based reverse genetics in plant parasitic nematodes (PPNs) remains inexplicably reliant on the use of long double-stranded RNA (dsRNA) silencing triggers; a practice inherently disadvantageous due to the introduction of superfluous dsRNA sequence, increasing chances of aberrant or off-target gene silencing through interactions between nascent short interfering RNAs (siRNAs) and non-cognate mRNA targets. Recently, we have shown that non-nematode, long dsRNAs have a propensity to elicit profound impacts on the phenotype and migrational abilities of both root knot and cyst nematodes. This study presents, to our knowledge for the first time, gene-specific knockdown of FMRFamide-like peptide (flp) transcripts, using discrete 21bp siRNAs in potato cyst nematode Globodera pallida, and root knot nematode Meloidogyne incognita infective (J2) stage juveniles. Both knockdown at the transcript level through quantitative (q)PCR analysis and functional data derived from migration assay, indicate that siRNAs targeting certain areas of the FMRFamide-like peptide (FLP) transcripts are potent and specific in the silencing of gene function. In addition, we present a method of manipulating siRNA activity through the management of strand thermodynamics. Initial evaluation of strand thermodynamics as a determinant of RNA-Induced Silencing Complex (RISC) strand selection (inferred from knockdown efficacy) in the siRNAs presented here suggested that the purported influence of 5' stand stability on guide incorporation may be somewhat promiscuous. However, we have found that on strategically incorporating base mismatches in the sense strand of a G. pallida-specific siRNA, we could specifically increase or decrease the knockdown of its target (specific to the antisense strand), presumably through creating more favourable thermodynamic profiles for incorporation of either the sense (non-target-specific) or antisense (target-specific) strand into a cleavage-competent RISC. Whilst the efficacy of similar approaches to siRNA modification has been demonstrated in the context of Drosophila whole-cell lysate preparations and in mammalian cell cultures, it remained to be seen how these sense strand mismatches may impact on gene silencing in vivo, in relation to different targets and in different sequence contexts. This work presents the first application of such an approach in a whole organism; initial results show promise. PMID:19651131

Dalzell, Johnathan J; McMaster, Steven; Fleming, Colin C; Maule, Aaron G

2010-01-01

184

Efeito da incorporação de sementes trituradas defeijão de porco ao solo sobre o parasitismo de Meloidogyne incognita em tomateiro Effect of soil amendment with powdered seeds of pig bean on Meloidogyne incognita in tomato  

Directory of Open Access Journals (Sweden)

Full Text Available Avaliou-se, em condições de casa de vegetação, o efeito da suplementação do solo com sementes trituradas de feijão de porco (Canavalia ensiformis sobre os índices de galhas e de massas de ovos de Meloidogyne incognita raça 1 em tomateiro (Lycopersicon esculentum. O substrato utilizado foi solo autoclavado suplementado com 2,5; 5,0; 7,5 e 10,0 g de sementes trituradas/kg de solo. Solo sem a suplementação serviu como testemunha. Para efeito de comparação, o nematicida Carbofuran foi incluído como tratamento adicional. Controle do nematóide foi obtido a partir da incorporação de 5,0 g de sementes trituradas/kg de solo, sendo o efeito proporcional à dosagem. Os índices de galhas e massas de ovos foram reduzidos em 48% e 64%, respectivamente, com a aplicação de 10 g de sementes trituradas/kg de solo.A greenhouse experiment was carried out to study the effect of powdered seeds of pig bean (Canavalia ensiformis incorporated into the soil, for the control of Meloidogyne incognita race 1 in tomato (Lycopersicon esculentum plants. Autoclaved soil was amended with 2.5, 5.0, 7.5 and 10.0 g of powdered seeds/kg of soil. Soil without amendment served as control. For comparison, the nematicide Carbofuran was included as an additional treatment. Nematode was controlled at rates above 5.0 g. Gall and egg mass indexes were reduced by 48% and 64%, respectively, with the application of 10 g of powdered seeds/kg of soil.

GILSON S. SILVA

2002-07-01

185

Infectividade de juvenis do segundo estádio de Meloidogyne incognita em tomateiro após privação alimentar em solo e água em diferentes condições / Infectivity of second stage juveniles of Meloidogyne incognita in tomato after starvation in soil and water at different conditions  

Scientific Electronic Library Online (English)

Full Text Available O juvenil do segundo estádio (J2) de Meloidogyne spp. gasta sua reserva energética corporal de formas diferentes sob condições variadas de temperatura e umidade do solo, chegando à incapacidade de parasitismo vegetal. Desta forma, objetivou-se neste trabalho estudar o efeito da incubação de J2 de M. [...] incognita em solo com níveis de umidade e temperaturas diferentes, além do borbulhamento da suspensão do inóculo na infectividade desses J2 em tomateiro. A infectividade dos J2 armazenados no solo em tomateiros decresceu significativamente entre as temperaturas estudadas durante o período de seis dias. Maior (P Abstract in english The second stage juvenile (J2) of Meloidogyne spp. spend the storaged energy of the body, differently, when living in variable conditions of soil temperatures and humidities approaching to the incapability of plant parasitism. Therefore, the aim of this work was to study the storage of J2 of M. inco [...] gnita in soil at different levels of humidity and temperature, besides water bubbling of inoculum suspension on the infectivity of starved J2 in tomato. The infectivity of J2 in tomato decreased significantly among storaged temperatures during the period of six days in soil. Greatest (P

Eduardo Souza, Freire; Vicente Paulo, Campos; Marcos Roberto, Dutra; Fernando da Silva, Rocha; Juliana Resende Campos da, Silva; Edson Ampélio, Pozza.

2007-09-01

186

Volatile Substances Produced by Fusarium oxysporum from Coffee Rhizosphere and Other Microbes affect Meloidogyne incognita and Arthrobotrys conoides.  

Science.gov (United States)

Microorganisms produce volatile organic compounds (VOCs) which mediate interactions with other organisms and may be the basis for the development of new methods to control plant-parasitic nematodes that damage coffee plants. In the present work, 35 fungal isolates were isolated from coffee plant rhizosphere, Meloidogyne exigua eggs and egg masses. Most of the fungal isolates belonged to the genus Fusarium and presented in vitro antagonism classified as mutual exclusion and parasitism against the nematode-predator fungus Arthrobotrys conoides (isolated from coffee roots). These results and the stronger activity of VOCs against this fungus by 12 endophytic bacteria may account for the failure of A. conoides to reduce plant-parasitic nematodes in coffee fields. VOCs from 13 fungal isolates caused more than 40% immobility to Meloidogyne incognita second stage juveniles (J2), and those of three isolates (two Fusarium oxysporum isolates and an F. solani isolate) also led to 88-96% J2 mortality. M. incognita J2 infectivity decreased as a function of increased exposure time to F. oxysporum isolate 21 VOCs. Gas chromatography-mass spectrometry (GC-MS) analysis lead to the detection of 38 VOCs produced by F. oxysporum is. 21 culture. Only five were present in amounts above 1% of the total: dioctyl disulfide (it may also be 2-propyldecan-1-ol or 1-(2-hydroxyethoxy) tridecane); caryophyllene; 4-methyl-2,6-di-tert-butylphenol; and acoradiene. One of them was not identified. Volatiles toxic to nematodes make a difference among interacting microorganisms in coffee rhizosphere defining an additional attribute of a biocontrol agent against plant-parasitic nematodes. PMID:23482720

Freire, E S; Campos, V P; Pinho, R S C; Oliveira, D F; Faria, M R; Pohlit, A M; Noberto, N P; Rezende, E L; Pfenning, L H; Silva, J R C

2012-12-01

187

Reaction of vegetables and aromatic plants to Meloidogyne javanica and M. incognita Reação de hortaliças e plantas aromáticas aos nematoides Meloidogyne javanica e M. incognita  

Directory of Open Access Journals (Sweden)

Full Text Available For this research we used 15 day-old seedlings which were transplanted to 2 L pots and inoculated with 4,000 nematode eggs plus juveniles (J2. After 60 days, the root systems were removed and the number of galls and eggs evaluated and used to calculate the nematode reproduction factor (RF. The tomato cv. Santa Cruz was used as a susceptible control. The experimental design was completely randomized, with six replications. Averages were compared using the Tukey or Scott-Knott test at 5%. For lettuce, Salad Bowl (Mimosa type, Elizabeth and Elisa (Lisa and Vera cultivars (crisphead, the number of galls and the RF for M. javanica were statistically higher than for the control, whereas, for the other vegetable crops, the highest number of galls and eggs were found in chicory and basil. The highest susceptibility to M. incognita was observed in Mimosa lettuce cv. Salad Bowl, chicory cultivars, parsley cv. Graúda Portuguesa and basil. Marjoram exhibited no M. incognita galls.Para avaliar a reação, mudas com 15 dias de idade foram transplantadas para vasos de 2 L de capacidade e inoculadas com 4.000 ovos e eventuais juvenis (J2 dos nematoides. Decorridos 60 dias, os sistemas radiculares foram retirados e avaliados quanto ao número de galhas e ovos, determinando-se o fator de reprodução (FR dos nematoides nas respectivas plantas. Tomateiro cv. Santa Cruz foi utilizado como testemunha. O experimento foi conduzido em delineamento inteiramente casualizado, com seis repetições, e as médias foram comparadas pelo teste Tukey ou Scott-Knott a 5% de probabilidade. Nas alfaces tipo Mimosa cv. Salad Bowl; nas cultivares do tipo Lisa, Elizabeth e Elisa; e na cultivar Vera (tipo crespa, o número de galhas e o FR de M. javanica foi superior ao observado para a testemunha; enquanto para as demais oleráceas, os maiores números de galhas e ovos foram para as cultivares de chicória e para o manjericão. Maior suscetibilidade a M. incognita foi observada para a alface tipo Mimosa cv. Salad Bowl, para as cultivares de chicória, salsa cv. Graúda Portuguesa e manjericão. Apenas manjerona apresentou número de galhas de M. incognita igual a zero.

Cláudia Regina Dias-Arieira

2012-06-01

188

Reaction of vegetables and aromatic plants to Meloidogyne javanica and M. incognita / Reação de hortaliças e plantas aromáticas aos nematoides Meloidogyne javanica e M. incognita  

Scientific Electronic Library Online (English)

Full Text Available Para avaliar a reação, mudas com 15 dias de idade foram transplantadas para vasos de 2 L de capacidade e inoculadas com 4.000 ovos e eventuais juvenis (J2) dos nematoides. Decorridos 60 dias, os sistemas radiculares foram retirados e avaliados quanto ao número de galhas e ovos, determinando-se o fat [...] or de reprodução (FR) dos nematoides nas respectivas plantas. Tomateiro cv. Santa Cruz foi utilizado como testemunha. O experimento foi conduzido em delineamento inteiramente casualizado, com seis repetições, e as médias foram comparadas pelo teste Tukey ou Scott-Knott a 5% de probabilidade. Nas alfaces tipo Mimosa cv. Salad Bowl; nas cultivares do tipo Lisa, Elizabeth e Elisa; e na cultivar Vera (tipo crespa), o número de galhas e o FR de M. javanica foi superior ao observado para a testemunha; enquanto para as demais oleráceas, os maiores números de galhas e ovos foram para as cultivares de chicória e para o manjericão. Maior suscetibilidade a M. incognita foi observada para a alface tipo Mimosa cv. Salad Bowl, para as cultivares de chicória, salsa cv. Graúda Portuguesa e manjericão. Apenas manjerona apresentou número de galhas de M. incognita igual a zero. Abstract in english For this research we used 15 day-old seedlings which were transplanted to 2 L pots and inoculated with 4,000 nematode eggs plus juveniles (J2). After 60 days, the root systems were removed and the number of galls and eggs evaluated and used to calculate the nematode reproduction factor (RF). The tom [...] ato cv. Santa Cruz was used as a susceptible control. The experimental design was completely randomized, with six replications. Averages were compared using the Tukey or Scott-Knott test at 5%. For lettuce, Salad Bowl (Mimosa type), Elizabeth and Elisa (Lisa) and Vera cultivars (crisphead), the number of galls and the RF for M. javanica were statistically higher than for the control, whereas, for the other vegetable crops, the highest number of galls and eggs were found in chicory and basil. The highest susceptibility to M. incognita was observed in Mimosa lettuce cv. Salad Bowl, chicory cultivars, parsley cv. Graúda Portuguesa and basil. Marjoram exhibited no M. incognita galls.

Cláudia Regina, Dias-Arieira; Tatiana PL da, Cunha; Fernando Marcelo, Chiamolera; Heriksen H, Puerari; Fabio, Biela; Simone de M, Santana.

2012-06-01

189

Efeito de exsudatos de cultura de células de plantas em juvenis de segundo estádio de Meloidogyne incognita / Effect of exudates of plant cell culture on second-stage juveniles of Meloidogyne incognita  

Scientific Electronic Library Online (English)

Full Text Available Calus foram obtidos de tomateiro (Lycopersicon esculentum), cafeeiro (Coffea arabica), alfafa (Medicago sativa), orquídea (Dendrobium nobile), mostarda (Brassica rapa), batata doce (Ipomoea batatas), fumo (Nicotiana tabacum), cenoura (Daucus carota) e Crotalaria juncea em meio sólido de Murashige & [...] Skoog (MS) seguido do cultivo em meio líquido MS em temperatura de 25-28 ºC. Após um mês, a suspensão foi passada em membrana Millipore 0,22 µm, obtendo-se, assim, o exsudato da cultura de células de cada planta testada. Ovos ou juvenis de segundo estádio (J2) de Meloidogyne incognita foram incubados nesses exsudatos e avaliadas as percentagens de eclosão, mobilidade e mortalidade dos J2. Com exceção dos ovos incubados em exsudato de orquídea, todos os demais inibiram a eclosão quando comparados com a incubação em água (testemunha). Entretanto, nos exsudatos de L. esculentum, cafeeiro e C. juncea a inibição foi mais drástica, semelhante ao aldicarb, mas significativamente diferente e menor do que em soluções contendo ingredientes do meio MS (1-5). Todos os exsudatos reduziram a mobilidade e aumentaram a mortalidade, com maior intensidade em 24 h de exposição. Porém, maior redução na mobilidade ocorreu nos exsudatos de tomateiro e alfafa, enquanto maior mortalidade no exsudato de tomateiro, seguido pelo de mostarda. Abstract in english Callus of Lycopersicon esculentum, Coffea arabica, Medicago sativa, Dendrobium nobile, Brassica rapa, Ipomoea batatas, Nicotiana tabacum, Daucus carota and Crotalaria juncea were obtained in Murashige & Skoog (MS) solid medium followed by cell cultivation in MS liquid medium at temperature varying f [...] rom 25-28 ºC. After one month, the cell suspension was passed through a 0,22 µm Millipore membrane, and the resulting liquid was the cell exudate from each of the tested plants. Eggs or second-stage juveniles (J2) of Meloidogyne incognita were then incubated in these exudates and hatching, mobility and mortality percentages of the J2 were evaluated. Except for the eggs incubated in the exudate of orchid, all the exudates inhibited J2 hatching when compared with incubation in water (control). However, in L. esculentum, C. arabica and C. juncea exudates the inhibition was greatest, similar to aldicar, but significantly less and different than that found in solution of culture medium ingredients MS (1-5). All exudates reduced mobility and increased mortality of M. incognita J2, although theses were enhanced when exposed for 24 h. The greatest reduction of mobility occurred with the exudates of tomato and M. sativa, while greatest mortality occurred with the exudate of L. esculentum, followed by B. rapa.

Fernando S., Rocha; Vicente P., Campos.

2004-06-01

190

Nematicidal activity of the essential oil of Rhododendron anthopogonoides aerial parts and its constituent compounds against Meloidogyne incognita.  

Science.gov (United States)

Hydrodistilled essential oil from Rhododendron anthopogonoides Maxim. (Ericaceae) aerial parts was analysed by gas chromatography-mass spectrometry (GC-MS). A total of 42 compounds, accounting for 95.48% of the total oil, were identified. The main constituents of the essential oil were benzyl acetone (34.41%), nerolidol (10.19%), 1,4-cineole (8.41%), beta-caryophyllene (5.63%), gamma-elemene (5.10%), and spathulenol (3.06%). Four constituents were isolated from the essential oil based on fractionation. The essential oil of R. anthopogonoides possessed nematicidal activity against the root knot nematode (Meloidogyne incognita) with an LC50 value of 130.11 microg/ml. The main compound of the essential oil, benzyl acetone, exhibited nematicidal activity against M. incognita with an LC50 value of 74.17 microg/ml while 1,4-cineole, nerolidol, and beta-caryophyllene were not nematicidal at a concentration of 5 mg/ml. The essential oil of R. anthopogonoides and benzyl acetone show potential for their development as possible natural nematicides for the control of the root knot nematode. PMID:24066516

Bai, Peng Hua; Bai, Chun Qi; Liu, Qi Zhi; Du, Shu Shan; Liu, Zhi Long

2013-01-01

191

Transformation of the endophytic fungus Acremonium implicatum with GFP and evaluation of its biocontrol effect against Meloidogyne incognita.  

Science.gov (United States)

Acremonium implicatum is an endophytic fungus with biocontrol potential against Meloidogyne incognita based on its opportunistic egg-parasitic, hatching inhibition, and toxic properties. To understand its mode of plant endophytism and opportunistic egg parasitism, GFP-tagged A. implicatum was constructed by PEG-mediated protoplast transformation. By laser scanning confocal microscopy (LSCM), we evaluated the endophytism and opportunistic egg parasitism of a stable gfp transformant (Acr-1). Acr-1 could colonize epidermal tissue, cortical tissue, and xylem of roots and form a mutualistic symbiosis with tomato host plants. LSCM of Acr-1 infecting M. incognita eggs revealed that hyphae penetrated the shell and grew inside eggs to form trophic hyphae. A large number of hyphae enveloped parasitized eggs. In addition, the egg shell integrity was destroyed by fungal penetration. The percentage of egg parasitism was 33.8 %. There were no marked differences between the wild type and mutant in nematode second-stage juvenile mortality and egg hatching and in fungal control efficiency in a pot experiment. In conclusion, gfp-transformation did not change the nematicidal activity of A. implicatum and is a tool to examine the mode of plant endophytism and opportunistic egg parasitism of A. implicatum. PMID:25724297

Yao, Yu-Rong; Tian, Xue-Liang; Shen, Bao-Ming; Mao, Zhen-Chuan; Chen, Guo-Hua; Xie, Bing-Yan

2015-04-01

192

Bioefficacy evaluation of controlled release formulations based on amphiphilic nano-polymer of carbofuran against Meloidogyne incognita infecting tomato.  

Science.gov (United States)

In the present investigation, the bioefficacy of developed carbofuran formulations, with PEG-600 (7a, CP1) & PEG-900 (7b, CP2) @ 5, 10 and 20 ppm, along with commercial formulation of carbofuran 3G (CP0) were evaluated against the root-knot nematode, Meloidogyne incognita infecting tomato (cv. Pusa Ruby) in pot and field conditions. The bioefficacy data indicated that the formulations developed by utilizing polymers having PEG - 900 (7b) as hydrophilic segment were effective even at 14 days post inoculation (dpi) as evident from shoot and root length. Also, the reduction in penetration was found to be maximum with CP2 (3.6 - 4.6 J2s) at all concentrations compared to CP1 (6.6-16.4 J2s) and CP0 (29.3-32.6 J2s). Overall, CP2 was more effective in reducing the number of nematodes up to 14 days, compared to CP1 and CP0. Both the CR formulations (CP1 and CP2) in general significantly reduced the number of galls, when compared to CP0. However, under field conditions, lower concentrations (5, and 10 ppm) of CP2, were less effective in controlling the gall formation whereas, CP2 at 20 ppm, was most effective than other treatments. The study revealed that the developed CR formulations of carbofuran have the potential for effective management of M. incognita in tomato under field conditions. PMID:22494375

Pankaj; Shakil, Najam Akhtar; Kumar, Jitendra; Singh, M K; Singh, Khajan

2012-01-01

193

RNAi of MiASB caused high mortality of Meloidogyne incognita juveniles and inhibited the nematode disease  

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Full Text Available The southern root-knot nematode, Meloidogyne incognita, is one of the most prevalent and damaging plant-parasitic nematodes in the world and causes serious damages to agricultural production. We cloned a mitochondrial ATP synthase b subunit gene fragment of M. incognita (MiASB based on the nematode genomics prediction. By soaking in the MiASB dsRNA solution, the hatching of RNAi treated eggs was reduced by 60% compared to negative control and by 64% compared to untreated control. Mortality of RNAi treated second stage juvenile (J2 was 8.6 times higher than that of negative control and 26 times higher than the untreated control. Inoculating the RNAi treated egg masses and J2 to tomato seedlings showed the pathogencity was significantly reduced. For the RNAi treated egg masses, the amount of root galls on silence treated seedlings was reduced by 92% compared to that on the negative control seedlings, and reduced by 93% compared to that on untreated control seedlings. For the treated J2, the amount of root galls on silence treated seedlings was reduced by 83% and 86% compared to negative and untreated control seedlings, respectively. The study revealed the MiASB silence had a positive effect on prevention and control of root-knot nematode disease, and also showed that the MiASB may be involved in the pathogenesis of nematode, which provided new ideas and ways to the research of nematode pathology and nematode disease control.

Yonghong Huang

2013-08-01

194

Evidence of Differences between the Communities of Arbuscular Mycorrhizal Fungi Colonizing Galls and Roots of Prunus persica Infected by the Root-Knot Nematode Meloidogyne incognita?  

OpenAIRE

Arbuscular mycorrhizal fungi (AMF) play important roles as plant protection agents, reducing or suppressing nematode colonization. However, it has never been investigated whether the galls produced in roots by nematode infection are colonized by AMF. This study tested whether galls produced by Meloidogyne incognita infection in Prunus persica roots are colonized by AMF. We also determined the changes in AMF composition and biodiversity mediated by infection with this root-knot nematode. DNA f...

Alguacil, Maria Del Mar; Torrecillas, Emma; Lozano, Zenaida; Rolda?n, Antonio

2011-01-01

195

Nematicidal activity of leaf extracts from Lantana camara L. against Meloidogyne incognita (kofoid and white) chitwood and its use to manage roots infection of Solanum melongena L.  

OpenAIRE

Various concentrations of aqueous leaf extract of Lantana camara were assessed in vitro conditions against second stage juveniles (J2) of Meloidogyne incognita. The standard concentration 'S' of leaf extract was found to be highly nematostatic, where nematodes were completely paralyzed after 12 h and after 48 h of exposure, 96% of juveniles were killed at same concentration. However, the mortality of juveniles was 75% in S/2 dilution at 48 h. The degree of effectiveness and dilutions of extra...

Faheem Ahmad; Mohmad Azhar Rather; Mansoor Ahmad Siddiqui

2010-01-01

196

Virtual screening and in vitro assay of potential drug like inhibitors from spices against Glutathione-S-Transferase of Meloidogyne incognita  

OpenAIRE

Glutathione S-transferases (GSTs) enzymes are critical antioxidant and detoxification system responsible for long-term existence of nematodes in host species. Hence, 16 phytochemicals predicted and reported to have potential nematicidal activity have been docked to GST enzyme of Meloidogyne incognita to assess their binding affinity and inhibitory activity. In vitro effects of these phytochemicals from in silico results have been done for validation of docking studies and efficacy in...

Babu, Rosana O.; Moorkoth, Dinsha; Azeez, Shamina; Eapen, Santhosh J.

2012-01-01

197

Field Evaluation of Yield and Resistances of Local and Improved Sweet Potato (Ipomoeabatatas (L) Lam) Accessions to Cylas puncticollis and Meloidogyne incognita inSoutheastern Nigeria  

OpenAIRE

Aim of the study was to evaluate local and improved accessions of sweet potato for resistances to Cylas puncticollis and Meloidogyne incognita and identify suitable ones for incorporation in breeding programmes for the production of genetically resistant and high yielding varieties. The experiment was conducted at the University of Uyo, Teaching and Research Farm located at Use Offot-Uyo, Southeastern Nigeria and laid out in a randomized complete block design, with three replications. Eightee...

Bassey, Emmanuel E.

2012-01-01

198

Non-nematode-derived double-stranded RNAs induce profound phenotypic changes in Meloidogyne incognita and Globodera pallida infective juveniles.  

Science.gov (United States)

Nine non-nematode-derived double-stranded RNAs (dsRNAs), designed for use as controls in RNA interference (RNAi) screens of neuropeptide targets, were found to induce aberrant phenotypes and an unexpected inhibitory effect on motility of root knot nematode Meloidogyne incognita J2s following 24h soaks in 0.1 mg/ml dsRNA; a simple soaking procedure which we have found to elicit profound knockdown of neuronal targets in Globodera pallida J2s. We have established that this inhibitory phenomenon is both time- and concentration-dependent, as shorter 4h soaks in 0.1 mg/ml dsRNA had no negative impact on M. incognita J2 stage worms, yet a 10-fold increase in concentration to 1 mg/ml for the same 4h time period had an even greater qualitative and quantitative impact on worm phenotype and motility. Further, a 10-fold increase of J2s soaked in 0.1 mg/ml dsRNA did not significantly alter the observed phenotypic aberration, which suggests that dsRNA uptake of the soaked J2s is not saturated under these conditions. This phenomenon was not initially observed in potato cyst nematode G. pallida J2s, which displayed no aberrant phenotype, or diminution of migratory activity in response to the same 0.1 mg/ml dsRNA 24h soaks. However, a 10-fold increase in dsRNA to 1mg/ml was found to elicit comparable irregularity of phenotype and inhibition of motility in G. pallida, to that initially observed in M. incognita following a 24h soak in 0.1 mg/ml dsRNA. Again, a 10-fold increase in the number of G. pallida J2s soaked in the same volume of 1 mg/ml dsRNA preparation did not significantly affect the observed phenotypic deviation. We do not observe any global impact on transcript abundance in either M. incognita or G. pallida J2s following 0.1 mg/ml dsRNA soaks, as revealed by reverse transcriptase-PCR and quantitative PCR data. This study aims to raise awareness of a phenomenon which we observe consistently and which we believe signifies a more expansive deficiency in our knowledge and understanding of the variables inherent to RNAi-based investigation. PMID:19482028

Dalzell, Johnathan J; McMaster, Steven; Johnston, Michael J; Kerr, Rachel; Fleming, Colin C; Maule, Aaron G

2009-11-01

199

Efeito de exsudatos radiculares em endósporos de Pasteuria penetrans e em juvenis do segundo estádio de Meloidogyne incognita Effect of root exudates on endospores of Pasteuria penetrans and on second-stage juvenile of Meloidogyne incognita  

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Full Text Available Juvenis do segundo estádio (J2 de Meloidogyne incognita foram incubados nos exsudatos radiculares de soja (Glycine max, tomateiro (Lycopersicon esculentum, cafeeiro (Coffea arabica, feijoeiro (Phaseolus vulgaris, mostarda (Brassica rapa, Crotalaria juncea e C. spectabilis e em água por 12 h. Em seguida, realizou-se o teste de adesão por centrifugação ou por borbulhamento. Em outro ensaio, endósporos de Pasteuria penetrans foram incubados por quatro dias a 26 ºC nos exsudatos e submetidos à adesão em J2 de M. incognita, sob borbulhamento constante por 24 h em tubos contendo água. Os J2 com endósporos aderidos pelo teste de borbulhamento foram inoculados em mudas de tomateiro. Verificou-se que a incubação dos J2 por 12 h nos exsudatos radiculares testados reduziu o número de endósporos de P. penetrans por J2 independentemente do método de adesão empregado. Os J2 incubados nos exsudatos radiculares testados proporcionaram menor número de fêmeas parasitadas em tomateiro em relação à testemunha (água, bem como menor número de galhas com exceção dos J2 incubados em exsudato do próprio tomateiro. A reprodução dos J2 incubados nos exsudatos radiculares não foi afetada quando comparada à testemunha. A incubação dos endósporos nos exsudatos das plantas testadas reduziu a adesão e a infetividade em J2, em relação à testemunha. Após 28 dias da inoculação, observou-se redução no número de fêmeas parasitadas resultantes da infecção desses J2 com endósporos incubados em exsudatos radiculares comparada com aqueles incubados em água. O parasitismo do J2 com endósporos tratados com exsudatos radiculares e a reprodutividade de fêmeas oriundas da infetividade desses J2 foram semelhantes aos incubados em água.In one assay, second stage juveniles (J2 of Meloidogyne incognita were incubated in root exudates of soybean (Glycine max, tomato (Lycopersicon esculentum, coffee (Coffea arabica, bean (Phaseolus vulgaris, mustard (Brassica rapa, Crotalaria juncea and C. spectabilis and in water for 12 h, followed by endospores adhesion by centrifugation or by air bubbling. In another assay, endospores of Pasterius penetrans were incubated for four days at 26 ºC in the exudates and submitted to adhesion on J2 of M. incognita by constant air bubbling for 24 h in tubes containing water. The J2 with endospore adhesion by air bubbling were inoculated in tomato seedlings. The incubation of J2 for 12 h in the root exudates reduced the number of P. penetrans endospore per J2, regardless of the adhesion test used, and resulted in fewer parasitized females when compared with the control, as well as a lower number of galls, except in the J2 incubated in exudate of tomato. The reproduction of incubated J2 in the root exudates was not affected when compared to the control. The endospore incubation in the exudates of the tested plants reduced the adhesion and the infectivity of these endospores to J2 in relation to the control. After 28 days from inoculation, reduction was observed in the number of parasitized females resulting from infection of those J2 with endospore incubated in exudates when compared with those incubated in water. The parasitism of J2 with endospore treated with exudates and the reproduction of infected J2 females were similar to those incubated in water.

Fernando da Silva Rocha

2004-12-01

200

Enxertia e sua influencia na produção de pepino e reprodução de Meloidogyne javanica e M. incognita Effect of grafting on cucumber production and reproduction of Meloidogyne javanica and M. incognita  

Directory of Open Access Journals (Sweden)

Full Text Available A enxertia em porta-enxertos resistentes é uma técnica frequentemente recomendada para a cultura do pepino em áreas infestadas com nematoides-das-galhas. O presente trabalho teve como objetivo avaliar a produção de pepino enxertado em dois porta-enxertos comparado com pé-franco em solo infestado com Meloidogyne incognita raça 2 ou com M. javanica. Foram avaliados nove tratamentos (fatorial 3x3: pepino híbrido Tsuyataro pé-franco, enxertado na abóbora híbrida 'Shelper' e enxertado na abóbora híbrida 'Excitte Ikki' x sem inoculação, inoculação com M. incognita e inoculação com M. javanica, no delineamento em blocos ao acaso, com quatro repetições e seis plantas por parcela. Para as características de produção de frutos (número de frutos totais e comerciais por planta, massa de frutos totais e comerciais por planta não foi obtida interação entre os fatores. Obteve-se maior produção de frutos em plantas enxertadas sobre a abóbora 'Shelper', independente da espécie de nematoide, enquanto que a enxertia sobre 'Excitte Ikki' não diferiu do pé-franco para produção total. Ambas as espécies de nematoide reduziram a produção de frutos, porém este efeito foi mais pronunciado com M. javanica. Tanto o pepino pé-franco como as plantas enxertadas foram suscetíveis, pois permitiram a multiplicação dos nematoides, com fator de reprodução, em avaliação realizada aos 72 dias após a inoculação, variando de 3,57 a 15,04, sendo que para M. javanica este valor foi maior no pepino pé-franco.Grafting on resistant rootstock is a technique often recommended for cucumber crop in root-knot nematodes infested areas. We studied the yield of grafted cucumber on two rootstocks compared with non grafted in soil infested with Meloidogyne javanica or with M. incognita race 2. Nine treatments (factorial 3x3: Japanese cucumber hybrid Tsuyataro without grafting, grafted on squash hybrid Shelper and grafted on squash hybrid Excitte Ikki x without nematode inoculation, inoculated with M. incognita and inoculated with M. javanica were evaluated in a randomized block design, with four replications and six plants per plot. There was no interaction between factors for yield evaluated characteristics (total and marketable fruit number per plant, total and marketable fruit weight per plant. Higher fruit yield was obtained in cucumber grafted on 'Shelper', for both nematode species, while cucumber grafted on 'Excitte Ikki' did not differ from non grafted plants for total fruit weight. Both nematode species reduced fruit yield, which was more evident when M. javanica was inoculated. Grafted and non grafted plants were susceptible, because they enabled the multiplication of nematodes, with a reproduction factor, at 72 days after inoculation, ranging from 3.57 to 15.04, with the highest value in cucumber non grafted inoculated with M. javanica.

Ariane C Salata

2012-12-01

201

Enxertia e sua influencia na produção de pepino e reprodução de Meloidogyne javanica e M. incognita / Effect of grafting on cucumber production and reproduction of Meloidogyne javanica and M. incognita  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese A enxertia em porta-enxertos resistentes é uma técnica frequentemente recomendada para a cultura do pepino em áreas infestadas com nematoides-das-galhas. O presente trabalho teve como objetivo avaliar a produção de pepino enxertado em dois porta-enxertos comparado com pé-franco em solo infestado com [...] Meloidogyne incognita raça 2 ou com M. javanica. Foram avaliados nove tratamentos (fatorial 3x3: pepino híbrido Tsuyataro pé-franco, enxertado na abóbora híbrida 'Shelper' e enxertado na abóbora híbrida 'Excitte Ikki' x sem inoculação, inoculação com M. incognita e inoculação com M. javanica), no delineamento em blocos ao acaso, com quatro repetições e seis plantas por parcela. Para as características de produção de frutos (número de frutos totais e comerciais por planta, massa de frutos totais e comerciais por planta) não foi obtida interação entre os fatores. Obteve-se maior produção de frutos em plantas enxertadas sobre a abóbora 'Shelper', independente da espécie de nematoide, enquanto que a enxertia sobre 'Excitte Ikki' não diferiu do pé-franco para produção total. Ambas as espécies de nematoide reduziram a produção de frutos, porém este efeito foi mais pronunciado com M. javanica. Tanto o pepino pé-franco como as plantas enxertadas foram suscetíveis, pois permitiram a multiplicação dos nematoides, com fator de reprodução, em avaliação realizada aos 72 dias após a inoculação, variando de 3,57 a 15,04, sendo que para M. javanica este valor foi maior no pepino pé-franco. Abstract in english Grafting on resistant rootstock is a technique often recommended for cucumber crop in root-knot nematodes infested areas. We studied the yield of grafted cucumber on two rootstocks compared with non grafted in soil infested with Meloidogyne javanica or with M. incognita race 2. Nine treatments (fact [...] orial 3x3: Japanese cucumber hybrid Tsuyataro without grafting, grafted on squash hybrid Shelper and grafted on squash hybrid Excitte Ikki x without nematode inoculation, inoculated with M. incognita and inoculated with M. javanica) were evaluated in a randomized block design, with four replications and six plants per plot. There was no interaction between factors for yield evaluated characteristics (total and marketable fruit number per plant, total and marketable fruit weight per plant). Higher fruit yield was obtained in cucumber grafted on 'Shelper', for both nematode species, while cucumber grafted on 'Excitte Ikki' did not differ from non grafted plants for total fruit weight. Both nematode species reduced fruit yield, which was more evident when M. javanica was inoculated. Grafted and non grafted plants were susceptible, because they enabled the multiplication of nematodes, with a reproduction factor, at 72 days after inoculation, ranging from 3.57 to 15.04, with the highest value in cucumber non grafted inoculated with M. javanica.

Ariane C, Salata; Erick Vinicius, Bertolini; Felipe O, Magro; Antonio II, Cardoso; Silvia Renata S, Wilcken.

2012-12-01

202

Efeito de exsudatos radiculares em endósporos de Pasteuria penetrans e em juvenis do segundo estádio de Meloidogyne incognita / Effect of root exudates on endospores of Pasteuria penetrans and on second-stage juvenile of Meloidogyne incognita  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Juvenis do segundo estádio (J2) de Meloidogyne incognita foram incubados nos exsudatos radiculares de soja (Glycine max), tomateiro (Lycopersicon esculentum), cafeeiro (Coffea arabica), feijoeiro (Phaseolus vulgaris), mostarda (Brassica rapa), Crotalaria juncea e C. spectabilis e em água por 12 h. E [...] m seguida, realizou-se o teste de adesão por centrifugação ou por borbulhamento. Em outro ensaio, endósporos de Pasteuria penetrans foram incubados por quatro dias a 26 ºC nos exsudatos e submetidos à adesão em J2 de M. incognita, sob borbulhamento constante por 24 h em tubos contendo água. Os J2 com endósporos aderidos pelo teste de borbulhamento foram inoculados em mudas de tomateiro. Verificou-se que a incubação dos J2 por 12 h nos exsudatos radiculares testados reduziu o número de endósporos de P. penetrans por J2 independentemente do método de adesão empregado. Os J2 incubados nos exsudatos radiculares testados proporcionaram menor número de fêmeas parasitadas em tomateiro em relação à testemunha (água), bem como menor número de galhas com exceção dos J2 incubados em exsudato do próprio tomateiro. A reprodução dos J2 incubados nos exsudatos radiculares não foi afetada quando comparada à testemunha. A incubação dos endósporos nos exsudatos das plantas testadas reduziu a adesão e a infetividade em J2, em relação à testemunha. Após 28 dias da inoculação, observou-se redução no número de fêmeas parasitadas resultantes da infecção desses J2 com endósporos incubados em exsudatos radiculares comparada com aqueles incubados em água. O parasitismo do J2 com endósporos tratados com exsudatos radiculares e a reprodutividade de fêmeas oriundas da infetividade desses J2 foram semelhantes aos incubados em água. Abstract in english In one assay, second stage juveniles (J2) of Meloidogyne incognita were incubated in root exudates of soybean (Glycine max), tomato (Lycopersicon esculentum), coffee (Coffea arabica), bean (Phaseolus vulgaris), mustard (Brassica rapa), Crotalaria juncea and C. spectabilis and in water for 12 h, foll [...] owed by endospores adhesion by centrifugation or by air bubbling. In another assay, endospores of Pasterius penetrans were incubated for four days at 26 ºC in the exudates and submitted to adhesion on J2 of M. incognita by constant air bubbling for 24 h in tubes containing water. The J2 with endospore adhesion by air bubbling were inoculated in tomato seedlings. The incubation of J2 for 12 h in the root exudates reduced the number of P. penetrans endospore per J2, regardless of the adhesion test used, and resulted in fewer parasitized females when compared with the control, as well as a lower number of galls, except in the J2 incubated in exudate of tomato. The reproduction of incubated J2 in the root exudates was not affected when compared to the control. The endospore incubation in the exudates of the tested plants reduced the adhesion and the infectivity of these endospores to J2 in relation to the control. After 28 days from inoculation, reduction was observed in the number of parasitized females resulting from infection of those J2 with endospore incubated in exudates when compared with those incubated in water. The parasitism of J2 with endospore treated with exudates and the reproduction of infected J2 females were similar to those incubated in water.

Fernando da Silva, Rocha; Vicente P., Campos; Ricardo Magela de, Souza.

2004-12-01

203

Reação de cultivares de algodoeiro a Meloidogyne incognita em condições de campo e casa de vegetação no estado de Mato Grosso / Reaction of cotton genotypes to Meloidogyne incognita in field and greenhouse trials in Mato Grosso state, Brazil  

Scientific Electronic Library Online (English)

Full Text Available Genótipos de algodoeiro, compreendendo cultivares e linhagens avançadas, foram avaliados no Estado de Mato Grosso quanto à reação a Meloidogyne incognita. Em dois experimentos de campo, foi avaliada a tolerância a esse nematóide mediante atribuição de notas, de acordo com sintomas externos exibidos [...] pelas plantas. Um ensaio avaliou também a resistência ao parasita, mediante determinação do número de espécimes nas raízes de plantas amostradas nas parcelas. A resistência foi avaliada também em casa de vegetação, por meio da determinação do número de massas de ovos nas raízes e do fator de reprodução. Foram constatadas diferenças notáveis na reação dos 22 genótipos estudados, verificando-se a formação de grupos graduais de desempenho, tanto com respeito à resistência quanto à tolerância. Nas duas características, destacaram-se positivamente as cultivares IAC 25 RMD, IPR 140 e IPR JATAÍ, e negativamente, dentre outras, FIBERMAX 966, LDCV FREGO e FMT 703. A produção de algodão em caroço variou de 482 a 3087 g/parcela no experimento de Campo Verde, e de 1153 a 3151 g/parcela no de Primavera do Leste. As perdas na produção, nos genótipos mais afetados, foram de até 65% no primeiro experimento e de até 40% no segundo. Os dados de avaliação da resistência e da tolerância mostraram-se correlacionados, porém, os da tolerância, a julgar pelos coeficientes de variação e de correlação intra-classe, na análise da variância, mostraram-se mais precisos e de maior repetibilidade. Abstract in english Cotton genotypes, comprising cultivars and advanced lineages, were evaluated for tolerance and resistance to Meloidogyne incognita in Mato Grosso state, Brazil. Tolerance was evaluated in two field experiments, attributing scores according to external symptoms exhibited by plants, while resistance w [...] as studied in greenhouse and in one field trial, counting the number of egg masses or specimens on the roots, and the reproduction factor. Significant differences were observed among the 22 studied genotypes, concerning both resistance and tolerance, and graduated performance groups were established. The cultivars IAC 25 RMD, IPR 140 and IPR JATAI formed the most resistant/tolerant group, while FIBERMAX 966, LDCV FREGO, and FMT 703, among others, were situated in the most susceptible/intolerant ones. Cotton seed yield ranged from 482 to 3087 g/plot at Campo Verde and from 1153 to 3151 g/plot at Primavera do Leste. Yield losses, attributable to incidence of this nematode, were estimated at 65% and 40%, respectively, in these trials. Data related to resistance and to tolerance were correlated, however, and by taking into account coefficient of variation and intra-class correlation, from the analysis of variance, it could be seen that data relating to tolerance presented greater precision and repeatability.

Rafael, Galbieri; Milton G., Fuzatto; Edivaldo, Cia; Reginaldo R., Lüders; Andressa C.Z., Machado; Alberto F., Boldt.

2009-02-01

204

Grafted eggplant yield, quality and growth in infested soil with Verticillium dahliae and Meloidogyne incognita / Produção, qualidade e crescimento de beringela enxertada, em solo infestado com Verticillium dahliae e Meloidogyne incognita  

Scientific Electronic Library Online (English)

Full Text Available O objetivo deste trabalho foi avaliar o efeito sobre a altura de planta, a produção e a qualidade de frutos do enxerto das cultivares de beringela (Solanum melongena L.) Pala e Faselis em Solanum torvum Sw., quando cultivadas em solo infestado com Verticillium dahliae e Meloidogyne incognita ou em s [...] olo não infestado. A infestação do solo reduziu a produção, altura da planta, biomassa da parte aérea, massa média dos frutos, massa de matéria seca da parte aérea, conforme a cultivar utilizada e a enxertia. A enxertia reduziu os conteúdos de ácido oxálico e de sólidos solúveis e aumentou a massa média de frutos, conforme a cultivar ou a presença do patógeno no solo. A enxertia também reduziu o efeito negativo dos patógenos sobre o índice de doença, a altura de planta e a massa de matéria seca da parte aérea. A cultivar Pala foi mais vigorosa que a Faselis, e S. torvum foi um porta-enxerto vigoroso. A combinação de porta-enxerto vigoroso com a cultivar fraca (Faselis) foi mais adequada que a de porta-enxerto vigoroso e a cultivar vigorosa (Pala). Ouso de S. torvum como porta-enxerto para a cultivar Faselis, em solo infestado, é provavelmente promissora na horticultura convencional e na horticultura sustentável de baixos insumos, pois a enxertia aumenta a proteção contra os patógenos, e reduz a perda de qualidade dos frutos e da produção. Abstract in english The objective of this work was to evaluate the effect of grafting (onto Solanum torvum Sw.) on plant growth, yield and fruit quality of the Pala and Faselis eggplant (Solanum melongena L.) cultivars, grown in a soil infested with Verticillium dahliae Kleb. and Meloidogyne incognita, or in noninfeste [...] d soil. Soil infestation decreased yield, plant height, final above-ground biomass, and also reduced fruit mean weight and shoot dry weight depending on cultivar or grafting. Grafting decreased fruit oxalic acid and the soluble solid contents, and increased mean fruit weight, depending on cultivar and soil infestation. Grafting also reduced the negative effects of the pathogens on disease index, plant height and shoot dry weight. Cultivar Pala was more vigorous than Faselis, and S. torvum was a vigorous rootstock. The combination of a vigorous rootstock with a weak cultivar (Faselis) is more profitable than that of a vigorous rootstock and a vigorous cultivar (Pala). Using S. torvum as a rootstock for cultivar Faselis, grown in soil infested with the pathogens, is most likely to be useful in conventional and low-input sustainable horticulture, since grafting increases protection against the pathogens, and reduces the losses in quality and yield.

205

Efeito de extratos aquosos de espécies de Asteraceae sobre Meloidogyne incognita / Effect of aqueous extracts of Asteraceae species on Meloidogyne incognita  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Estudou-se, in vitro e in vivo a atividade nematicida dos extratos aquosos de vedélia (Sphagneticola trilobata), erva-de-touro (Tridax procumbens), cravo-de-defunto (Tagetes patula), girassol mexicano (Tithonia diversifolia), botão de ouro (Unxia suffruticosa) e zínia (Zinnia peruviana), sobre Meloi [...] dogyne incognita. Os extratos foram preparados na proporção de 1,0g do material seco e triturado para 10mL de água destilada e armazenados por 24h, sendo seguidamente utilizados nos experimentos. Nos testes in vitro, foram depositados 4,0mL do extrato bruto e 2,0mL de uma suspensão aquosa contendo 200 ovos do nematóide em placas de Petri de 5cm de diâmetro e, quinze dias após, procedeu-se a contagem do número de juvenis eclodidos e dos ovos remanescentes para o cálculo das porcentagens de eclosão. Nos testes in vivo, os extratos foram aplicados, separadamente, via pulverização foliar, tratamento de raiz e vertido no solo, semanalmente durante 60 dias. Como testemunha utilizou-se apenas água nos dois experimentos. No ensaio in vitro observou-se que todos os extratos foram eficientes na redução da eclosão de juvenis de M. incognita quando comparados à testemunha, as porcentagens de redução foram 89,96%, 91,13%, 92,48%, 92,72%, 93,2% e 97,48% para erva-de-touro, cravo-de-defunto, girassol mexicano, vedélia, botão de ouro e zínia, respectivamente, e no ensaio in vivo, que os tratamentos não exerceram nenhum efeito sobre o peso do sistema radicular dos tomateiros, no entanto, observou-se que os resultados diferiram entre as espécies utilizadas e a forma de aplicação do extrato na avaliação do peso fresco da parte aérea das plantas. Quanto ao fator de reprodução, observou-se que nenhum dos extratos apresentou diferença estatística em relação à testemunha, no entanto, quando se compara as diferentes formas de aplicação dos mesmos, observa-se que houve diferença estatística quando os extratos de erva de touro e girassol mexicano foram aplicados via pulverização foliar e no tratamento de raiz, contudo, não houve diferença quando estes extratos foram aplicados em forma de rega no solo. Abstract in english The nematicide activity of aqueous extracts of Wedelia (Sphagneticola trilobata), tridax daisy (Tridax procumbens), marigold (Tagetes patula), Mexican sunflower (Tithonia diversifolia), "botão de ouro" (Unxia suffruticosa) and Peruvian zinnia (Zinnia peruviana) was studied in vitro and in vivo on Me [...] loidogyne incognita. The extracts were prepared at a ratio of 1.0 g of dry and crushed material to 10 ml of distilled water, stored for 24 hours, and then used in the experiments. In in vitro tests, 4.0 mL of crude extract and 2.0 ml of an aqueous suspension containing 200 nematode eggs were deposited on Petri plates of 5cm diameter and, fifteen days later, the number of hatched juveniles and the remaining eggs were counted to calculate the percentages of hatching. In in vivo tests, the extracts were separately applied by leaf spraying, root treatment and pouring onto the soil, weekly for 60 days. As control, only water was used in both experiments. The in vitro test showed that all extracts were effective in reducing the hatching of juveniles of M. incognita when compared to the control; the reduction percentages were 89.96%, 91.13%, 92.48%, 92.72%, 93.2% and 97.48% for tridax daisy, marigold, Mexican sunflower, Wedelia, "botão de ouro" and Peruvian zinnia, respectively, while in the in vivo assay, treatments did not have any effect on the root system weight of tomato plants; however, results differed between the used species and the way of application of the extract in the evaluation of the fresh weight of shoots. As to the reproduction rate, none of the extracts showed a statistical difference, compared to control; however, comparing the different ways of application, there was statistical difference when the extracts of tridax daisy and Mexican sunflower were applied through leaf spraying and root

Isabel Cristina Madeira, Ferreira; Gilson Soares da, Silva; Fagner Sousa, Nascimento.

2013-03-01

206

Pyramiding taro cystatin and fungal chitinase genes driven by a synthetic promoter enhances resistance in tomato to root-knot nematode Meloidogyne incognita.  

Science.gov (United States)

Meloidogyne incognita, one of the major root-knot nematode (RKN) species in agriculture, attacks many plant species, causing severe economic losses. Genetic engineering of plants with defense-responsive genes has been demonstrated to control RKN. These studies, however, focused on controlling RKN at certain growth stages. In the present study, a dual gene overexpression system, utilizing a plant cysteine proteinase inhibitor (CeCPI) and a fungal chitinase (PjCHI-1), was used to transform tomato (Solanum lycopersicum) in order to provide protection from all growth stages of RKN. A synthetic promoter, pMSPOA, containing NOS-like and SP8a elements, was employed to drive the expression of introduced genes. Gall formation and the proportion of female nematodes in the population, as well as effects on the reproduction of RKN, were monitored in both transgenic and control plants. RKN eggs collected from transgenic plants displayed reduced chitin content and retardation in embryogenesis. The results demonstrated that transgenic plants had inhibitory effects on RKN that were superior to plants transformed with a single gene. The pyramiding expression system produced synergistic effects by the two defense-responsive genes, leading to a detrimental effect on all growth stages of RKN. PMID:25575993

Chan, Yuan-Li; He, Yong; Hsiao, Tsen-Tsz; Wang, Chii-Jeng; Tian, Zhihong; Yeh, Kai-Wun

2015-02-01

207

Morphological and Morphometrical Characterization of Meloidogyne incognita from Different Host Plants in Four Districts of Punjab, India  

OpenAIRE

The population of M. incognita, the root knot nematode (RKN) was found infesting five different host plants (okra, banana, sunflower, bottle gourd, and brinjal) out of 24 examined from four districts of Punjab, India (Gurdaspur, Ludhiana, Patiala, and Hoshiarpur). Morphological and morphometrical characterization indicated that in the case of mature female, the characters of body length and width, neck length, ratio ‘a’, anus to tail terminus (ATT), interphasmid distance (IPD), and perine...

Kaur, Harpreet; Attri, Rajni

2013-01-01

208

Evaluation of Verticilum Chlamydosporium and Arrthrobotrys for Biological Control of Meloidogyne Incognita in Celery and Tomato  

International Nuclear Information System (INIS)

The ability of nematode trapping fungi and egg-parasitic fungi to colonize and persist in the rhizosphere of crop plants is thought to be an important factor influencing the success of bi logical control of root infecting nematodes. In this study, two strains of an egg parasite fungus Verticillium chlamydosporium (Vc-10 and Vc-2M) and an isolate of the nematode-trapping fungus Arthrobotrys oligospora and persistence in the rhizosphere and tomato plants in a green house pot experiment. The isolates tested differed in their pathogenicity to M. incognita and survival in the rhizosphere. An isolate of Verticillum chlamydosporium (Vc-10) was the most virulent pathogen of the nematode. Root galling was slowest in tomato plants treated with V-10 (2.2); pots treated with this isolate had the lowest final soil population of infective juveniles; there was a 62.2% and 98.5% infections of eggs and egg masses respectively by Vc-10 on tomato plants. The two isolates of Verticillium chlamydosporium (Vc-10 and Vc2M) persisted in the soil and could be re-isolated from the rhizosphere and roots of tomato plants at least 16 weeks after soil application. The final inoculum density was, however higher for Vc-10 (1.35x105 cfu/g soil) than Vc-2M (9.25x104 cfu/g soil). Arthrobotrys oligospora on the other hand did not give any significant control of the nematode on both crops, there was severe galling on the roots of plants treated with this agent. It could not be re-isted with this agent. It could not be re-isolated from the plant rhizosphere sixteen weeks after soil infestation. Lack of nematode control on both crops by A.oligo spora was attributed to it's poor on establishment in the plant rhizosphere; low density and roots penetration by infective juveniles before they were ensnared in the trapping devices of this fungal biocontrol agent. The fact that it could not be re-isolated from the rhizosphere may imply that the fungus did not survive in the rhizosphere in quantities enough to enhance nematode control

209

Exploitation of microbes for enhancing bacoside content and reduction of Meloidogyne incognita infestation in Bacopa monnieri L.  

Science.gov (United States)

Despite the vast exploration of rhizospheric microbial wealth for crop yield enhancement, knowledge about the efficacy of microbial agents as biocontrol weapons against root-knot disease is scarce, especially in medicinal plants, viz., Bacopa monnieri. In the present investigation, rhizospheric microbes, viz., Bacillus megaterium, Glomus intraradices, Trichoderma harzianum ThU, and their combinations were evaluated for the management of Meloidogyne incognita (Kofoid and White) Chitwood and bacoside content enhancement in B. monnieri var CIM-Jagriti. A novel validated method Fourier transform near infrared was used for rapid estimation of total bacoside content. A significant reduction (2.75-fold) in root-knot indices was observed in the combined treatment of B. megaterium and T. harzianum ThU in comparison to untreated control plants. The same treatment also showed significant enhancement (1.40-fold) in total bacoside contents (plant active molecule) content using Fourier transform near-infrared (FT-NIR) method that analyses samples rapidly in an hour without solvent usage and provides ample scope for natural product studies. PMID:24841892

Gupta, Rupali; Tiwari, Sudeep; Saikia, Shilpi K; Shukla, Virendra; Singh, Rashmi; Singh, S P; Kumar, P V Ajay; Pandey, Rakesh

2015-01-01

210

Effects of chloroform extract of Dryopteris crassirhizoma on the ultramicroscopic structures of Meloidogyne incognita.  

Science.gov (United States)

In our early experiments, the chloroform extract of D. crassirhizoma was demonstrated to contain the highest concentrations of total phloroglucinols among several extract fractions and possessed the most effective nematicidal activity. This study aimed to ascertain the ultrastructural changes in M. incognita after treatment with a D. crassirhizoma chloroform extract at 1?mg·mL?¹ for 24?h. It was found that the extract exhibited significant destructive effects on the worm's ultrastructure and caused distinctive damage to body surfaces and internal structures. These results will contribute to a deeper understanding of the nematicidal mechanism of D. crassirhizoma, as well as in the design of efficient bionematicides. PMID:24282379

Liu, Ji-quan; Xie, Shu-lian; Feng, Jia; Cai, Jin

2013-01-01

211

An SXP/RAL-2 protein produced by the subventral pharyngeal glands in the plant parasitic root-knot nematode Meloidogyne incognita.  

Science.gov (United States)

Meloidogyne incognita is a major parasite of numerous plant families, including many crop species. Upon infection of the plant root, it induces several multinucleate giant cells by the injection of pharyngeal gland secretions into the root cells. In order to obtain a better understanding of the nematode-plant interaction, characterization of the pharyngeal gland secretions is a necessity. By differential display, a nematode gene was identified that encodes a new member of the SXP/RAL-2 protein family. The gene is specifically expressed in the subventral pharyngeal glands and the protein is most likely secreted. PMID:15565464

Tytgat, Tom; Vercauteren, Isabel; Vanholme, Bartel; De Meutter, Jan; Vanhoutte, Isabelle; Gheysen, Greetje; Borgonie, Gaetan; Coomans, August; Gheysen, Godelieve

2005-01-01

212

The role of betaines in alkaline extracts of Ascophyllum nodosum in the reduction of Meloidogyne javanica and M. incognita infestations of tomato plants  

OpenAIRE

L'application sur les racines de plants de tomates d'un extrait alcalin de l'algue brune #Ascophyllum nodosum$, disponible dans le commerce, produit une réduction significative du nombre de juvéniles de deuxième stade de #Meloidogyne javanica$ et #M. incognita$ pénétrant dans les racines, en comparaison avec des plants de tomates traités uniquement avec de l'eau. Le nombre d'oeufs récupérés sur les plants traités par l'extrait d'algue est également significativement plus faible. Lo...

Wu, Y.; Jenkins, T.; Blunden, G.; Whapham, C.; Hankins, S. D.

1997-01-01

213

Efecto in vitro de concentraciones del NEMACID® sobre huevos y juveniles de Meloidogyne incognita (Kofoid y White) Chitwood / In vitro effect of different concentrations of NEMACID® on eggs and juveniles of Meloidogyne incognita (Kofoid and White) Chitwood  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish Para el manejo de nematodos, se desarrolló en Cuba el producto NEMACID®, que posee como ingrediente activo metabolitos obtenidos a partir de los efluentes de la fermentación líquida de Lecanicillium lecanii (Zare & Gams) formulado con sulfato de amonio. El objetivo de este ensayo fue determinar el e [...] fecto del NEMACID® sobre los huevos y juveniles (J2) de Meloidogyne incognita (Kofoid y White) Chitwood. En el ensayo se utilizaron como controles agua destilada, sulfato de amonio ((NH4)2SO4; 1,69 mg.ml-1) y Dazomet (1g.1000ml-1); y se evaluaron cinco concentraciones de NEMACID® (18,75; 3,75; 1,875; 0, 1875 y 0,01875mg.ml-1). Los valores de LC50 y LC90, se calcularon usando el método Probit. Las evaluaciones se llevaron a cabo a las 24 horas, contabilizándose el número de J2 inmóviles y huevos no eclosionados del total. Los resultados corroboraron la acción nematicida del producto que provocó el colapso del contenido interno de los juveniles y resultó imposible su recuperación posterior. El NEMACID® a la concentración de 18,75 mg.ml-1 produjo mayor efectividad sobre la eclosión de los huevos y mortalidad de los juveniles que el Dazomet (control). El sulfato de amonio, producto que acompaña al hongo en el proceso de fermentación y forma parte de la formulación final del NEMACID®, no produjo afectación a huevos y juveniles. Las concentraciones de NEMACID® de 3,75 mg.ml-1 e inferiores no resultaron satisfactorias en el tratamiento de los huevos, donde el porcentaje de inhibición de la eclosión de los mismos estuvo por debajo del 50. Mientras que en juveniles, la concentración de 3,75 mg.ml-1 del producto ocasionó mortalidad por encima del 70%, sin diferencia significativa con el producto Dazomet. Abstract in english NEMACID® was developed in Cuba for root knot nematode management. This product contains the effluents from liquid fermentation of Lecanicillium lecani (Zare and Gams) as active ingredient, and is formulated with ammonium sulfate. The objective of this test was to determine the effect of NEMACID® on [...] eggs and juveniles (J2) of Meloidogyne incognita (Kofoid and White) Chitwood. In the test, five concentrations of NEMACID® (18,75; 3,75; 1,875; 0,1875 y 0,01875mg.ml-1) were evaluated using distilled water, ammonium sulfate ((NH4)2SO4; 1,69mg.ml-1) and Dazomet (1g.1000ml-1) as controls. The CL50 and CL90 were calculated using Probit analysis. The evaluations were done at 24h, when the total number of non mobile juveniles and non hatched eggs from the total were counted. The result corroborated the nematicide action of the product by producing the collapse of the internal content in juveniles with an impossible recovery. NEMACID® at a concentration of 18,75 mg. ml-1 showed a higher effect on egg hatching and juvenile mortality than Dazomet (control). The ammonium sulfate, a product accompanying the fungus in the fermentation process as part of the final formulation of NEMACID®, did not affect eggs or juveniles. Concentrations of NEMACID® equal to 3,75mg.ml-1 or lower did not affect the eggs, with a percentage of hatching inhibition below 50%. Meanwhile, in juveniles, the concentration of 3.75mg.ml-1 caused a mortality over 70%, without significant differences with Dazomet.

Yusmila, Guevara; Eulalia, Gómez; Oriela, Pino; Y, Rodríguez; Ileana, Miranda; R, Enrique; Mayra G, Rodríguez.

2013-04-01

214

Uptake and translocation of nitrogen, phosphorus and calcium in soybean infected with Meloidogyne incognita and M. javanica / Absorção e transporte de nitrogênio, fósforo e cálcio em soja infetada com Meloidogyne incognita e M. javanica  

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Full Text Available SciELO Brazil | Language: English Abstract in portuguese Duas cultivares de soja (Glycine max) foram usadas neste estudo, Ocepar 4, moderadamente resistente a Meloidogyne incognita raça 3, mas suscetível a M. javanica, e 'BR 16', suscetível a ambos nematóides. O efeito da infecção de nematóides na absorção e transporte de N, P e Ca para a parte aérea foi [...] estudada em plantas crescendo em um sistema da raízes divividas, sendo a parte superior das raízes inoculada com 0, 3.000, 9.000 ou 27.000 ovos/planta, enquanto a inferior recebeu 15N, 32P ou 45Ca. Plantas infetadas mostraram aumento de raízes, mas diminuição da massa da parte aérea com o aumento do inóculo. De modo geral, as quantidades endógenas totais dos elementos estudados aumentaram nas raízes e tenderam a diminuir na parte aérea com o aumento do inóculo. Quando os dados foram expressos em concentração do elemento/massa de tecido, observou-se aumento para os três elementos nas raízes e aumento de Ca na parte aérea. A quantidade total de 15N nas raízes aumentou no maior nível de inóculo, havendo diminuição de 32P e 45Ca. Na parte aérea, houve redução de 32P e 45Ca. As concentrações específicas dos elementos marcados (abundância ou radioatividade/massa de tecido) também mostrou diminuição de 32P e 45Ca na parte aérea e raízes de plantas infetadas, e aumento de 15N na parte aérea. Considerando que as quantidades endógenas dos elementos refletem a absorção cumulativa e que os dados de elementos marcados fornecem informação de um momento específico da infecção, nematóides interferem de fato com a absorção e translocação de nutrientes. Abstract in english Two soybean (Glycine max) cultivars were used in this study, Ocepar 4, rated as moderately resistant to Meloidogyne incognita race 3 but susceptible to M. javanica, and 'BR 16', susceptible to both nematodes. The effect of nematodes infection on the uptake and transport of N, P and Ca to the shoot w [...] as studied in plants growing in a split root system. The upper half was inoculated with 0, 3,000, 9,000 or 27,000 eggs/plant while the lower half received 15N, 32P or 45Ca. Infected plants showed an increase of root but a decrease of shoot mass with increasing inoculum levels. In general, total endogenous nutrients increased in the roots and tended to decrease in the shoots with increasing inoculum levels. When concentrations were calculated, there was an increase in the three nutrients in the roots, and an increase of Ca but no significant variation of N and P was observed in the shoots. The total amount of 15N in the roots increased at the highest inoculum levels but 32P and 45Ca decreased. In the shoots there was a reduction of 32P and 45Ca. The specific concentrations of the labelled nutrients (abundance or radioactivity/tissue mass) also showed a decrease of 32P and 45Ca in the shoots and roots of infected plants and an increase of 15N in the shoots. Considering that overall nutrient concentrations reflect cumulative nutrient uptake and the data from labelled elements gave information at a specific moment of the infection, thus nematodes do interfere with nutrient uptake and translocation.

RUI G., CARNEIRO; PAULO, MAZZAFERA; LUIZ CARLOS C.B., FERRAZ; TAKASHI, MURAOKA; PAULO CESAR O., TRIVELIN.

2002-04-01

215

Uptake and translocation of nitrogen, phosphorus and calcium in soybean infected with Meloidogyne incognita and M. javanica Absorção e transporte de nitrogênio, fósforo e cálcio em soja infetada com Meloidogyne incognita e M. javanica  

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Full Text Available Two soybean (Glycine max cultivars were used in this study, Ocepar 4, rated as moderately resistant to Meloidogyne incognita race 3 but susceptible to M. javanica, and 'BR 16', susceptible to both nematodes. The effect of nematodes infection on the uptake and transport of N, P and Ca to the shoot was studied in plants growing in a split root system. The upper half was inoculated with 0, 3,000, 9,000 or 27,000 eggs/plant while the lower half received 15N, 32P or 45Ca. Infected plants showed an increase of root but a decrease of shoot mass with increasing inoculum levels. In general, total endogenous nutrients increased in the roots and tended to decrease in the shoots with increasing inoculum levels. When concentrations were calculated, there was an increase in the three nutrients in the roots, and an increase of Ca but no significant variation of N and P was observed in the shoots. The total amount of 15N in the roots increased at the highest inoculum levels but 32P and 45Ca decreased. In the shoots there was a reduction of 32P and 45Ca. The specific concentrations of the labelled nutrients (abundance or radioactivity/tissue mass also showed a decrease of 32P and 45Ca in the shoots and roots of infected plants and an increase of 15N in the shoots. Considering that overall nutrient concentrations reflect cumulative nutrient uptake and the data from labelled elements gave information at a specific moment of the infection, thus nematodes do interfere with nutrient uptake and translocation.Duas cultivares de soja (Glycine max foram usadas neste estudo, Ocepar 4, moderadamente resistente a Meloidogyne incognita raça 3, mas suscetível a M. javanica, e 'BR 16', suscetível a ambos nematóides. O efeito da infecção de nematóides na absorção e transporte de N, P e Ca para a parte aérea foi estudada em plantas crescendo em um sistema da raízes divividas, sendo a parte superior das raízes inoculada com 0, 3.000, 9.000 ou 27.000 ovos/planta, enquanto a inferior recebeu 15N, 32P ou 45Ca. Plantas infetadas mostraram aumento de raízes, mas diminuição da massa da parte aérea com o aumento do inóculo. De modo geral, as quantidades endógenas totais dos elementos estudados aumentaram nas raízes e tenderam a diminuir na parte aérea com o aumento do inóculo. Quando os dados foram expressos em concentração do elemento/massa de tecido, observou-se aumento para os três elementos nas raízes e aumento de Ca na parte aérea. A quantidade total de 15N nas raízes aumentou no maior nível de inóculo, havendo diminuição de 32P e 45Ca. Na parte aérea, houve redução de 32P e 45Ca. As concentrações específicas dos elementos marcados (abundância ou radioatividade/massa de tecido também mostrou diminuição de 32P e 45Ca na parte aérea e raízes de plantas infetadas, e aumento de 15N na parte aérea. Considerando que as quantidades endógenas dos elementos refletem a absorção cumulativa e que os dados de elementos marcados fornecem informação de um momento específico da infecção, nematóides interferem de fato com a absorção e translocação de nutrientes.

RUI G. CARNEIRO

2002-04-01

216

Damage quantification and reaction of bean genotypes (Phaseolus vulgaris L.) to Meloidogyne incognita race 3 and M. javanica / Quantificação de danos e reção de genótipos de feijoeiro (Phaseolus vulgaris L.) à Meloidogyne incognita raça 3 e M. javanica  

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Full Text Available SciELO Brazil | Language: English Abstract in portuguese Avaliaram-se danos e os níveis de resistência de cultivares e acessos de feijoeiro-comum resgatados nas regiões Sul e Serrana do Estado do Espírito Santo ao parasitismo de M. incognita raça 3 e M. javanica em casa de vegetação. Foram testados quatro genótipos resgatados de feijoeiro ("FORT-10", "FOR [...] T-13", "FORT-16" e "FORT-19"), e mais 2 cultivares comerciais: "Pérola"; e "Aporé". O cultivar "Rico-23" foi incluído como padrão de suscetibilidade aos nematóides e plantas não inoculadas constituíram a testemunha. Desta forma, o experimento foi conduzido em delineamento inteiramente casualizado em esquema fatorial 3 (tratamentos considerando nematóides) x 7 (genótipos e cultivares de feijoeiros), com 7 repetições. Os dados foram mensurados aos 50 dias após a inoculação das plantas. Para a quantificação de danos foram avaliadas: altura das plantas (ALT), número de nós (NOS), número de folhas trifolioladas (NFT), peso da matéria fresca (PMF) e da matéria seca (PMS) da parte aérea, peso de raiz (PR), número de nódulos radiculares (NOD) e população final (PF) de nematóides por sistema radicular. Não foram observadas diferenças significativas entre os efeitos causados por M. incognita e M. javanica, porém ambas as espécies apresentaram valores inferiores quanto à ALT, NOS, NFT, PR, PMF e PMS em relação às testemunhas. Em relação aos níveis de resistência dos feijoeiros a M. incognita os feijoeiros "FORT-10", "FORT-13", "Aporé" e "FORT-16" comportaram-se como moderadamente resistente, as cultivares "Rico 23" e "Pérola" como pouco resistente e o genótipo "FORT-19" como altamente suscetível. Quando parasitados por M. javanica, os feijoeiros "FORT-19", "Rico 23", "FORT-16" e "FORT-13" foram pouco resistentes, "Pérola" e "Aporé" suscetíveis e "FORT-10" altamente suscetíveis. Abstract in english The damage and the resistance levels of cultivars and accessions of common beans rescued in the South and mountain regions of Espírito Santo State, Brazil, to M. incognita race 3 and M. javanica parasitism were evaluated under a greenhouse. Four rescued bean genotypes ("FORT-10", "FORT-13", "FORT-16 [...] " and "FORT-19") and 2 commercial cultivars: "Pérola", and "Aporé", were tested. The cultivar "Rico-23" was included as standard of susceptibility to nematodes and non-inoculated plants constituted the control. Thus, the experiment was carried out in a completely randomized design in 3 (treatments considering nematodes) x 7 (genotypes and bean cultivars) factorial arrangement, with 7 replicates. Data were measured at 50 days after plant inoculation. For damage quantification, the following variables were evaluated: plant height (PHE), number of nodes (NNO), number of trifoliate leaves (NRT), fresh matter weight (FWE) and dry matter weight (DWE) of shoots, root weight (RWE), number of root nodules (NRO) and final population (FPO) of nematodes per root system. There were no significant differences between the effects caused by M. incognita and M. javanica, but both species showed inferior values of PHE, NNO, NRT, RWE, FWE and DWE compared to controls. Concerning the levels of resistance of bean plants to M. incognita, the genotypes "FORT-10", "FORT-13", "Aporé" and "FORT-16" behaved as moderately resistant, the cultivars "Rico 23" and "Pérola" low resistant, and the genotype "FORT-19" as highly susceptible. When parasitized by M. javanica, the beans "FORT-19", "Rico-23", "FORT-16" and "FORT-13" were low resistant, "Pérola" and "Aporé" susceptible and "FORT-10" highly susceptible.

Leonardo Nazário Silva dos, Santos; Fábio Ramos, Alves; Leônidas Leoni, Belan; Pablo Diego Silva, Cabral; Frederico de Pina, Matta; Waldir Cintra de, Jesus Junior; Willian Bucker de, Moraes.

2012-03-01

217

Tolerance to Rotylenchulus reniformis and Resistance to Meloidogyne incognita Race 3 in High-Yielding Breeding Lines of Upland Cotton.  

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Field experiments in 1992 and 1994 were conducted to determine the effect of Rotylenchulus reniformis, reniform nematode, on lint yield and fiber quality of 10 experimental breeding lines of cotton (Gossypium hirsutum) in untreated plots or plots fumigated with 1,3-dichloropropene. Controls were La. RN 1032, a germplasm line possessing some resistance to R. reniformis, and Stoneville 453, a cultivar that is susceptible to reniform nematode. Several breeding lines produced greater lint yields than Stoneville 453 or La. RN 1032 in both fumigated and untreated plots. Average lint yield suppression due to R. reniformis for six of the 10 breeding lines was less than half of the 52% yield reduction sustained by Stoneville 453. In growth chamber experiments, R. reniformis multiplication factors for La. RN 1032 and breeding lines N222-1-91, N320-2-91, and N419-1-91 were significantly lower than on Deltapine 16 and Stoneville 453 at 6 weeks after inoculation. R. reniformis populations increased by more than 50-fold on all entries within 10 weeks. In growth chambers, the breeding lines N220-1-92, N222-1-91, and N320-2-91 were resistant to Meloidoglyne incognita race 3; multiplication factors were cotton germplasm lines with the potential to produce higher yields in soils infested with R. reniformis or M. incogaita. In addition to good yield potential, germplasm lines N222-1-91 and N320-2-91 appear to possess low levels of resistance to R. reniformis and a high level of resistance to M. incognita. This germplasm combines high yield potential with significant levels of resistance to both R. reniformis and M. incognita. PMID:19274165

Cook, C G; Robinson, A F; Namken, L N

1997-09-01

218

Field Evaluation of Yield and Resistances of Local and Improved Sweet Potato (Ipomoeabatatas (L Lam Accessions to Cylas puncticollis and Meloidogyne incognita inSoutheastern Nigeria  

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Full Text Available Aim of the study was to evaluate local and improved accessions of sweet potato for resistances to Cylas puncticollis and Meloidogyne incognita and identify suitable ones for incorporation in breeding programmes for the production of genetically resistant and high yielding varieties. The experiment was conducted at the University of Uyo, Teaching and Research Farm located at Use Offot-Uyo, Southeastern Nigeria and laid out in a randomized complete block design, with three replications. Eighteen sweet potato accessions were studied, comprising 13 local accessions, namely: E5, B6, E3, B26, B2, E11, E6, E17, B21, E14, E7, B23, E10 and five IITA improved and recommended varieties (TIS 87/0087, TIS 8441, TIS 8164, TIS 2532 and TIS 86/0356 for southeastern Nigeria. Three of the IITA improved and recommended varieties (TIS 86/0356, TIS 8164 and TIS 87/0087 had higher number of root tubers per plot and higher root tuber yield per hectare than the local accessions, while eight of the local accessions indicated high resistances to Cylas puncticollis, namely: B6, B2, E17, B21, E14, E7, B23 and E10 and Meloidogyne incognita, namely: B6, E3, B26, B21, E14, E7, B23 and E10. The local accessions with high root tuber yields and very high resistances to C. puncticollis and M. incognita (B6, B21 and E10 could be incorporated in breeding programmes involving TIS 87/0087, TIS 8164, TIS 2532 and TIS 86/0356 for the production of hybrid varieties with higher yields and resistances to the pests in southeastern Nigeria.

Emmanuel E. Bassey

2012-11-01

219

Evidence of differences between the communities of arbuscular mycorrhizal fungi colonizing galls and roots of Prunus persica infected by the root-knot nematode Meloidogyne incognita.  

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Arbuscular mycorrhizal fungi (AMF) play important roles as plant protection agents, reducing or suppressing nematode colonization. However, it has never been investigated whether the galls produced in roots by nematode infection are colonized by AMF. This study tested whether galls produced by Meloidogyne incognita infection in Prunus persica roots are colonized by AMF. We also determined the changes in AMF composition and biodiversity mediated by infection with this root-knot nematode. DNA from galls and roots of plants infected by M. incognita and from roots of noninfected plants was extracted, amplified, cloned, and sequenced using AMF-specific primers. Phylogenetic analysis using the small-subunit (SSU) ribosomal DNA (rDNA) data set revealed 22 different AMF sequence types (17 Glomus sequence types, 3 Paraglomus sequence types, 1 Scutellospora sequence type, and 1 Acaulospora sequence type). The highest AMF diversity was found in uninfected roots, followed by infected roots and galls. This study indicates that the galls produced in P. persica roots due to infection with M. incognita were colonized extensively by a community of AMF, belonging to the families Paraglomeraceae and Glomeraceae, that was different from the community detected in roots. Although the function of the AMF in the galls is still unknown, we hypothesize that they act as protection agents against opportunistic pathogens. PMID:21984233

Alguacil, Maria del Mar; Torrecillas, Emma; Lozano, Zenaida; Roldán, Antonio

2011-12-01

220

Analysis of Gene expression in soybean (Glycine max roots in response to the root knot nematode Meloidogyne incognita using microarrays and KEGG pathways  

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Full Text Available Abstract Background Root-knot nematodes are sedentary endoparasites that can infect more than 3000 plant species. Root-knot nematodes cause an estimated $100 billion annual loss worldwide. For successful establishment of the root-knot nematode in its host plant, it causes dramatic morphological and physiological changes in plant cells. The expression of some plant genes is altered by the nematode as it establishes its feeding site. Results We examined the expression of soybean (Glycine max genes in galls formed in roots by the root-knot nematode, Meloidogyne incognita, 12 days and 10 weeks after infection to understand the effects of infection of roots by M. incognita. Gene expression was monitored using the Affymetrix Soybean GeneChip containing 37,500 G. max probe sets. Gene expression patterns were integrated with biochemical pathways from the Kyoto Encyclopedia of Genes and Genomes using PAICE software. Genes encoding enzymes involved in carbohydrate and cell wall metabolism, cell cycle control and plant defense were altered. Conclusions A number of different soybean genes were identified that were differentially expressed which provided insights into the interaction between M. incognita and soybean and into the formation and maintenance of giant cells. Some of these genes may be candidates for broadening plants resistance to root-knot nematode through over-expression or silencing and require further examination.

Gamal El-Din Abd El Kader Y

2011-05-01

221

Morphological and Morphometrical Characterization of Meloidogyne incognita from Different Host Plants in Four Districts of Punjab, India.  

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The population of M. incognita, the root knot nematode (RKN) was found infesting five different host plants (okra, banana, sunflower, bottle gourd, and brinjal) out of 24 examined from four districts of Punjab, India (Gurdaspur, Ludhiana, Patiala, and Hoshiarpur). Morphological and morphometrical characterization indicated that in the case of mature female, the characters of body length and width, neck length, ratio 'a', anus to tail terminus (ATT), interphasmid distance (IPD), and perineal pattern were recorded as stable characters. These taxonomic characters can be reliable for identification. All characters of second-stage juvenile (J2) such as body length, stylet length, head to median bulb length (H-MB), distance from median bulb to excretory pore (MB-EP), tail length, anal body width (ABW), and ratios C and C' were highly variable. Analysis of interpopulation morphometric characters of mature female of M. incognita, namely, body length, width, and ratio 'a' were moderately variable characters (CV 0.26% to 20%) and stylet length, neck length, length of median bulb (LMB), and width of median bulb (WMB) were highly variable (CV 1.0% to 36.1%). In the perineal pattern, the two characters ATT and IPD were moderately variable (CV 8.8% to 17.6%) and two characters, anus to vulval slit (AVS) and length of vulval slit (LVS), were highly variable (CV 2.1% to 40.5%). In J2, body length, stylet length, H-MB, MB-EP, ABW, tail length, ratios C, and C' were highly variable characters (CV > 12%). PMID:23833327

Kaur, Harpreet; Attri, Rajni

2013-06-01

222

Mi-1-mediated resistance to Meloidogyne incognita in tomato may not rely on ethylene but hormone perception through ETR3 participates in limiting nematode infection in a susceptible host.  

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Root-knot nematodes, Meloidogyne spp., are important pests of tomato (Solanum lycopersicum) and resistance to the three most prevalent species of this genus, including Meloidogyne incognita, is mediated by the Mi-1 gene. Mi-1 encodes a nucleotide binding (NB) leucine-rich repeat (LRR) resistance (R) protein. Ethylene (ET) is required for the resistance mediated by a subset of NB-LRR proteins and its role in Mi-1-mediated nematode resistance has not been characterized. Infection of tomato roots with M. incognita differentially induces ET biosynthetic genes in both compatible and incompatible interactions. Analyzing the expression of members of the ET biosynthetic gene families ACC synthase (ACS) and ACC oxidase (ACO), in both compatible and incompatible interactions, shows differences in amplitude and temporal expression of both ACS and ACO genes in these two interactions. Since ET can promote both resistance and susceptibility against microbial pathogens in tomato, we investigated the role of ET in Mi-1-mediated resistance to M. incognita using both genetic and pharmacological approaches. Impairing ET biosynthesis or perception using virus-induced gene silencing (VIGS), the ET-insensitive Never ripe (Nr) mutant, or 1-methylcyclopropene (MCP) treatment, did not attenuate Mi-1-mediated resistance to M. incognita. However, Nr plants compromised in ET perception showed enhanced susceptibility to M. incognita indicating a role for ETR3 in basal resistance to root-knot nematodes. PMID:23717408

Mantelin, Sophie; Bhattarai, Kishor K; Jhaveri, Teraneh Z; Kaloshian, Isgouhi

2013-01-01

223

Separate and Combined Effects of Fusarium oxysporum f. sp. tracheiphilum and Meloidogyne incognita on Growth and Yield of Cowpea (Vigna unguiculata L. Walp Var. Moussa-Local  

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Full Text Available A study was undertaken to determine the separate and combined affects of Fusarium oxysporum f. sp. tracheiphilum and Meloidogyne incognita on growth and yield of cowpea variety Moussa-local. It was observed that growth and yield components of the cowpea were generally reduced in all treatments as compared to that of control. Single infection with only nematode caused more growth and yield reductions than infection with only fungus. Reduction in the growth and yield components were generally higher in simultaneous infection than infection with either of the pathogens. Growth and yield reduction in combined infection did not vary significantly from those caused by successive infection where either of the pathogens was made to precede the other. Infection with both pathogens caused significant increases in the root galls, number of eggs and juveniles when compared with infection with nematode only.

A.O. Ogaraku

2008-01-01

224

Nematicidal activity of leaf extracts from Lantana camara L. against Meloidogyne incognita (kofoid and white chitwood and its use to manage roots infection of Solanum melongena L.  

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Full Text Available Various concentrations of aqueous leaf extract of Lantana camara were assessed in vitro conditions against second stage juveniles (J2 of Meloidogyne incognita. The standard concentration 'S' of leaf extract was found to be highly nematostatic, where nematodes were completely paralyzed after 12 h and after 48 h of exposure, 96% of juveniles were killed at same concentration. However, the mortality of juveniles was 75% in S/2 dilution at 48 h. The degree of effectiveness and dilutions of extract were directly proportional. The percentage of paralyzed juveniles was decreased, when J2 transferred in distilled water after 48 h incubation in standard aqueous leaf extract. Addition of freeze-dried aqueous extract to sterile sandy substrate at S/2 dilution significantly decreased the root-knot infection to susceptible eggplants whereas second stage juveniles (J2 that penetrated roots of eggplant were able to complete development in sterile sandy substrate without treatment of freeze-dried aqueous extract.

Faheem Ahmad

2010-06-01

225

Potentiality of different isolates of wilt fungus Fusarium oxysporum collected from rhizosphere of tomato against root-knot nematode Meloidogyne incognita.  

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This investigation was undertaken to determine the effect of culture filtrates of different isolates of Fusarium oxysporum f. sp. lycopersici on mortality of Meloidogyne incognita juveniles and egg hatching. It was observed that different concentrations including standard extract (S.E), 1:10 and 1:100 dilutions of all fungal filtrates inhibited egg hatch when compared with control. Minimum mortality and maximum hatching was observed in BRT (showing least mortality) isolate of F. oxysporum, while maximum mortality and minimum egg hatching was recorded in BGT (showing maximum mortality) isolate. Larval mortality was decreased with a decrease in concentration and the least mortality was observed in 1:100 when compared with SE and 1:10. The potentiality of both the isolates (BRT and BGT) against root-knot nematode M. incognita was confirmed by the pathogenicity test on tomato. These observations confirmed that F. oxysporumisolates possesses variability in pathogenicity ranging from pathogenic to bio-control agent. The plants inoculated with BRT isolate failed to show wilt symptoms while plants inoculated with BGT isolate showed wilt indices. PMID:18941992

Jain, Anju; Mohan, Jitendra; Singh, Mahendra; Goswami, B K

2008-11-01

226

Salicylic acid-induced glutathione status in tomato crop and resistance to root-knot nematode, Meloidogyne incognita (Kofoid & White Chitwood  

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Full Text Available Salicylic acid-(SA is a plant defense stimulator. Exogenous application of SA might influence the status of glutathione-(GSH. GSH activates and SA alters the expression of defense genes to modulate plant resistance against pathogens. The fate of GSH in a crop following SA treatment is largely unknown. The SA-induced profiles of free reduced-, free oxidized-(GSSG and protein bound-(PSSG glutathione in tomato crop following foliar treatment of transplant at 5.0-10.0 ?g mL–1 were measured by liquid chromatography. Resistance to root-knot nematode, Meloidogyne incognita damaging tomato and crop performance were also evaluated. SA treatment at 5.0-10.0 ?g mL–1 to tomato transplants increased GSH, GSSG and PSSG in plant leaf and root, more so in leaf, during crop growth and development. As the fruits ripened, GSH and PSSG increased and GSSG declined. SA reduced the root infection by M. incognita, nematode reproduction and thus, improved the resistance of tomato var. Pusa Ruby, but reduced crop growth and redox status. SA at 5.0 ?g mL–1 improved yield and fruit quality. The study firstly linked SA with activation of glutathione metabolism and provided an additional dimension to the mechanism of induced resistance against obligate nematode pathogen. SA increased glutathione status in tomato crop, imparted resistance against M. incognita, augmented crop yield and functional food quality. SA can be applied at 5.0 ?g mL–1 for metabolic engineering of tomato at transplanting to combine host-plant resistance and health benefits in formulating a strategic nematode management decision.

Ghanendra Singh

2011-05-01

227

Knocking-Down Meloidogyne incognita Proteases by Plant-Delivered dsRNA Has Negative Pleiotropic Effect on Nematode Vigor  

Science.gov (United States)

The root-knot nematode Meloidogyne incognita causes serious damage and yield losses in numerous important crops worldwide. Analysis of the M. incognita genome revealed a vast number of proteases belonging to five different catalytic classes. Several reports indicate that M. incognita proteases could play important roles in nematode parasitism, besides their function in ordinary digestion of giant cell contents for feeding. The precise roles of these proteins during parasitism however are still unknown, making them interesting targets for gene silencing to address protein function. In this study we have knocked-down an aspartic (Mi-asp-1), a serine (Mi-ser-1) and a cysteine protease (Mi-cpl-1) by RNAi interference to get an insight into the function of these enzymes during a host/nematode interaction. Tobacco lines expressing dsRNA for Mi-ser-1 (dsSER), Mi-cpl-1 (dsCPL) and for the three genes together (dsFusion) were generated. Histological analysis of galls did not show clear differences in giant cell morphology. Interestingly, nematodes that infected plants expressing dsRNA for proteases produced a reduced number of eggs. In addition, nematode progeny matured in dsSER plants had reduced success in egg hatching, while progeny resulting from dsCPL and dsFusion plants were less successful to infect wild-type host plants. Quantitative PCR analysis confirmed a reduction in transcripts for Mi-cpl-1 and Mi-ser-1 proteases. Our results indicate that these proteases are possibly involved in different processes throughout nematode development, like nutrition, reproduction and embryogenesis. A better understanding of nematode proteases and their possible role during a plant-nematode interaction might help to develop new tools for phytonematode control. PMID:24392004

Antonino de Souza Júnior, José Dijair; Ramos Coelho, Roberta; Tristan Lourenço, Isabela; da Rocha Fragoso, Rodrigo; Barbosa Viana, Antonio Américo; Lima Pepino de Macedo, Leonardo; Mattar da Silva, Maria Cristina; Gomes Carneiro, Regina Maria; Engler, Gilbert; de Almeida-Engler, Janice; Grossi-de-Sa, Maria Fatima

2013-01-01

228

Effects of Meloidogyne spp. and Rhizoctonia solani on the Growth of Grapevine Rootings  

OpenAIRE

A disease complex involving Meloidogyne incognita and Rhizoctonia solani was associated with stunting of grapevines in a field nursery. Nematode reproduction was occurring on both susceptible and resistant cultivars, and pot experiments were conducted to determine the virulence of this M. incognita population, and of M. javanica and M. hapla populations, to V. vinifera cv. Colombard (susceptible) and to V. champinii cv. Ramsey (regarded locally as highly resistant). The virulence of R. solani...

Walker, G. E.

1997-01-01

229

Variability of Meloidogyne exigua on Coffee in the Zona da Mata of Minas Gerais State, Brazil  

OpenAIRE

Minas Gerais is the major coffee-producing state of Brazil, with 28% of its production coming from the region of Zona da Mata. Four major species of root-knot nematode attacking coffee (Meloidogyne incognita, M. paranaensis, M. coffeicola, and M. exigua) have been reported from Brazil. To determine the variability in Meloidogyne spp. occurring in that region, 57 populations from 20 localities were evaluated for morphological, enzymatic, and physiological characteristics. According to the peri...

Oliveira, D. S.; Oliveira, R. D. L.; Freitas, L. G.; Silva, R. V.

2005-01-01

230

influence of some types of Algerian soil on the development of rot-knot nematodes Meloidogyne incognita, M. javanica and M. arenaria (Tylenchida,Meloidogynidae)  

International Nuclear Information System (INIS)

Crops under greenhouses offer the possibility of vegetables production of high added value by focusing on earliness. They help to spread the availability timing of vegetables and fruits in the market throughout the year. However, these crops are subject to numerous attacks entailing heavy losses of yield quantity and quality. The plant parasitic nematodes especially rot-knot nematodes of the genus Meloidogyne are considered dangerous enemies of these cultures. The evolution study of these nematodes in different soil types allows one to compare the migration and movement of these nematodes in sandy soils considered as light soils, in clay soils heavy and intermediate silty clay soils. These soils have also rates of organic matter and a percentage of magnesium and calcium that might provide better conditions to the survival and migration of second stage larvae inoculated at a rate of 650 juveniles per pot of 24 cm in diameter where plants of melon Cucumis melo var. (Charentais) known to be susceptible to Meloidogyne was cultivated. The results for the population development of Meloidogyne, after a growing period of 3 months show an increase in the number of eggs, juvenile stages, inflated, swollen females and males in the 3 types of soil and that independently of clay fraction although clay soil may asphyxiate Meloidogyne. The development of the three species of Meloidogyne studied in these soils, the parameters taken into consideration (index of galls, which were 1.58,deration (index of galls, which were 1.58, 1.75 and 1.5 for the sandy clay and the middle ground soils, vigour index and the evolution of populations of Meloidogyne and roots and soil as well as parameters related to production reveal the adaptation of these root-knot nematodes to the clay and sandy loam soils. At the end of culture, the final populations are important in the soils studied; 2680 for soil S. (sandy), 2272 for soil A (clay) and 2327 for soil I (intermediate) with a multiplication rate almost similar ( 4.12, 3.49 and 3.58 respectively). All these parameters can give one clues about the real possibility of developing root-knot nematodes on all types of soil. These findings may be real on the coastal areas of the southern regions characterized with sandy soils that are most infested, but the infestation potential of interior plains characterized by clay and clay loam are certain if necessary measures are not seriously taken to control them. (author)

231

Nematicidal activity of leaf extracts from Lantana camara L. against Meloidogyne incognita (kofoid and white) chitwood and its use to manage roots infection of Solanum melongena L.  

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Full Text Available SciELO Brazil | Language: English Abstract in english Various concentrations of aqueous leaf extract of Lantana camara were assessed in vitro conditions against second stage juveniles (J2) of Meloidogyne incognita. The standard concentration 'S' of leaf extract was found to be highly nematostatic, where nematodes were completely paralyzed after 12 h an [...] d after 48 h of exposure, 96% of juveniles were killed at same concentration. However, the mortality of juveniles was 75% in S/2 dilution at 48 h. The degree of effectiveness and dilutions of extract were directly proportional. The percentage of paralyzed juveniles was decreased, when J2 transferred in distilled water after 48 h incubation in standard aqueous leaf extract. Addition of freeze-dried aqueous extract to sterile sandy substrate at S/2 dilution significantly decreased the root-knot infection to susceptible eggplants whereas second stage juveniles (J2) that penetrated roots of eggplant were able to complete development in sterile sandy substrate without treatment of freeze-dried aqueous extract.

Faheem, Ahmad; Mohmad Azhar, Rather; Mansoor Ahmad, Siddiqui.

2010-06-01

232

Heterologous expression of taro cystatin protects transgenic tomato against Meloidogyne incognita infection by means of interfering sex determination and suppressing gall formation.  

Science.gov (United States)

Plant-parasitic nematodes are a major pest of many plant species and cause global economic loss. A phytocystatin gene, Colocasia esculenta cysteine proteinase inhibitor (CeCPI), isolated from a local taro Kaosiang No. 1, and driven by a CaMV35S promoter was delivered into CLN2468D, a heat-tolerant cultivar of tomato (Solanum lycopersicum). When infected with Meloidogyne incognita, one of root-knot nematode (RKN) species, transgenic T1 lines overexpressing CeCPI suppressed gall formation as evidenced by a pronounced reduction in gall numbers. In comparison with wild-type plants, a much lower proportion of female nematodes without growth retardation was observed in transgenic plants. A decrease of RKN egg mass in transgenic plants indicated seriously impaired fecundity. Overexpression of CeCPI in transgenic tomato has inhibitory functions not only in the early RKN infection stage but also in the production of offspring, which may result from intervention in sex determination. PMID:20054551

Chan, Yuan-Li; Yang, Ai-Hwa; Chen, Jen-Tzu; Yeh, Kai-Wun; Chan, Ming-Tsair

2010-03-01

233

Effect of soil texture and the clay component on migration of Meloidogyne incognita second-stage juveniles  

OpenAIRE

The vertical migration of M. incognita juveniles introduced at 20 cm from the roots was studied in five natural soils, 100% silica sand, 95% silica sand with 5% clay, 90% silica sand with 10% clay, and 95% silica sand with 5% clay as a concentrated layer. In natural soils the percentage of juveniles capable of migrating 20 cm and penetrating the roots decreased when the percentage of clay and silt increased. No migration occurred in silica sand without clay particles; when 5 or 10% of clay we...

Prot, Jean-claude; Gundy, S. D.

1981-01-01

234

Reaction of coffee genotypes to different populations of Meloidogyne spp.: detection of a naturally virulent M. exigua population / Reação de genótipos de cafeeiro a diferentes populações de Meloidogyne spp.: detecção de uma população de M. exigua naturalmente virulenta  

Scientific Electronic Library Online (English)

Full Text Available A reação de sete genótipos de Coffea arabica a 10 populações de Meloidogyne spp. coletadas principalmente em plantios de café no Brasil e Costa Rica foi avaliada em casa de vegetação. O inóculo consistiu de 10.000 ovos por planta. As avaliações foram realizadas 8 meses após as inoculações consideran [...] do-se a massa da matéria fresca das raízes, índices de galhas e massas de ovos, número de ovos por grama de raiz e fator de reprodução (FR). As cultivares Obatã IAC 1669-20, Sarchimor IAC 4361 e Tupi Amarelo IAC 5111 exibiram suscetibilidade às quatro populações brasileiras de M. exigua. Entretanto, cv. Tupi Vermelho IAC 1669-33 mostrou-se resistente (FR=0,7) a uma população de M. exigua proveniente de Lavras, MG, Brasil. A população de M. exigua oriunda de Bom Jesus de Itabapoana, RJ, Brasil foi altamente virulenta à cv. IAPAR 59 (FR= 165,7), portadora do gene de resistência Mex-1 e ao genótipo Paraíso (H 419-5-4-5-2) (FR=396,2). A população de Meloidogyne sp. do cafeeiro, Garça, SP, Brasil, reproduziu-se em baixos níveis (FR = 0,1 - 3,9) sobre todos os genótipos. Todas as cultivares testadas foram suscetíveis a M. incognita e M. paranaensis. A reprodução de M. mayaguensis obtida de goiabeira, PR, Brasil, foi baixa (FR = 0,0-1,6), em todos os genótipos. Entretanto, outra população obtida do cafeeiro na Costa Rica apresentou valores de FR que variaram de 0,8 a 12,4. Os resultados deste trabalho mostraram, pela primeira vez, a capacidade de uma população de M. exigua obtida em campo de superar a resistência conferida pelo gene Mex-1. Abstract in english The reaction of seven genotypes of Coffea arabica to 10 Meloidogyne spp. populations collected mainly from coffee plantations in Brazil and Costa Rica was evaluated under greenhouse conditions. The inoculum consisted of 10,000 eggs per plant. Evaluations were done 8 months after inoculations conside [...] ring the root fresh weight, gall and egg mass indices, number of eggs per gram of root and reproduction factor (RF). The cultivars Obatã IAC 1669-20, Sarchimor IAC 4361 and Tupi Amarelo IAC 5111 exhibited susceptibility to the four Brazilian M. exigua populations tested. However, cv. Tupi Vermelho IAC 1669-33 revealed resistance (RF value of 0.7) to the M. exigua population from Lavras, Minas Gerais State, Brazil. A population of M. exigua from Bom Jesus de Itabapoana, Rio de Janeiro State, Brazil, was highly virulent on cv. IAPAR 59 (RF= 165.7), bearing resistance gene Mex-1, and was also virulent on genotype Paraíso (H 419-5-4-5-2) (RF=396.2). A Meloidogyne sp. population on coffee from Garça, São Paulo State, Brazil, reproduced at low rates (RF ranging from 0.1 to 3.9) on all genotypes. All tested cultivars were susceptible to M. incognita and M. paranaensis. M. mayaguensis of guava from Paraná State, Brazil, reproduced at low rates in all coffee genotypes; however, another population of coffee, from Costa Rica, was more aggressive and showed RF value that ranged from 0.8 to 12.4. Results of this study point for the first time to the ability of a naturally occurring M. exigua population to overcome the resistance conferred by the Mex-1 gene.

Maria de Fátima S., Muniz; Vicente P., Campos; Antônio W., Moita; Wallace, Gonçalves; Maria Ritta A., Almeida; Fábio Rodrigues de, Sousa; Regina Maria D. G., Carneiro.

2009-12-01

235

Reaction of coffee genotypes to different populations of Meloidogyne spp.: detection of a naturally virulent M. exigua population Reação de genótipos de cafeeiro a diferentes populações de Meloidogyne spp.: detecção de uma população de M. exigua naturalmente virulenta  

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Full Text Available The reaction of seven genotypes of Coffea arabica to 10 Meloidogyne spp. populations collected mainly from coffee plantations in Brazil and Costa Rica was evaluated under greenhouse conditions. The inoculum consisted of 10,000 eggs per plant. Evaluations were done 8 months after inoculations considering the root fresh weight, gall and egg mass indices, number of eggs per gram of root and reproduction factor (RF. The cultivars Obatã IAC 1669-20, Sarchimor IAC 4361 and Tupi Amarelo IAC 5111 exhibited susceptibility to the four Brazilian M. exigua populations tested. However, cv. Tupi Vermelho IAC 1669-33 revealed resistance (RF value of 0.7 to the M. exigua population from Lavras, Minas Gerais State, Brazil. A population of M. exigua from Bom Jesus de Itabapoana, Rio de Janeiro State, Brazil, was highly virulent on cv. IAPAR 59 (RF= 165.7, bearing resistance gene Mex-1, and was also virulent on genotype Paraíso (H 419-5-4-5-2 (RF=396.2. A Meloidogyne sp. population on coffee from Garça, São Paulo State, Brazil, reproduced at low rates (RF ranging from 0.1 to 3.9 on all genotypes. All tested cultivars were susceptible to M. incognita and M. paranaensis. M. mayaguensis of guava from Paraná State, Brazil, reproduced at low rates in all coffee genotypes; however, another population of coffee, from Costa Rica, was more aggressive and showed RF value that ranged from 0.8 to 12.4. Results of this study point for the first time to the ability of a naturally occurring M. exigua population to overcome the resistance conferred by the Mex-1 gene.A reação de sete genótipos de Coffea arabica a 10 populações de Meloidogyne spp. coletadas principalmente em plantios de café no Brasil e Costa Rica foi avaliada em casa de vegetação. O inóculo consistiu de 10.000 ovos por planta. As avaliações foram realizadas 8 meses após as inoculações considerando-se a massa da matéria fresca das raízes, índices de galhas e massas de ovos, número de ovos por grama de raiz e fator de reprodução (FR. As cultivares Obatã IAC 1669-20, Sarchimor IAC 4361 e Tupi Amarelo IAC 5111 exibiram suscetibilidade às quatro populações brasileiras de M. exigua. Entretanto, cv. Tupi Vermelho IAC 1669-33 mostrou-se resistente (FR=0,7 a uma população de M. exigua proveniente de Lavras, MG, Brasil. A população de M. exigua oriunda de Bom Jesus de Itabapoana, RJ, Brasil foi altamente virulenta à cv. IAPAR 59 (FR= 165,7, portadora do gene de resistência Mex-1 e ao genótipo Paraíso (H 419-5-4-5-2 (FR=396,2. A população de Meloidogyne sp. do cafeeiro, Garça, SP, Brasil, reproduziu-se em baixos níveis (FR = 0,1 - 3,9 sobre todos os genótipos. Todas as cultivares testadas foram suscetíveis a M. incognita e M. paranaensis. A reprodução de M. mayaguensis obtida de goiabeira, PR, Brasil, foi baixa (FR = 0,0-1,6, em todos os genótipos. Entretanto, outra população obtida do cafeeiro na Costa Rica apresentou valores de FR que variaram de 0,8 a 12,4. Os resultados deste trabalho mostraram, pela primeira vez, a capacidade de uma população de M. exigua obtida em campo de superar a resistência conferida pelo gene Mex-1.

Maria de Fátima S. Muniz

2009-12-01

236

Efeito do armazenamento na energia corporal de juvenis do segundo estádio de Meloidogyne incognita infestados por Pasteuria penetrans / Effect of storage on body energy of second stage juveniles of Meloidogyne incognita infested by Pasteuria penetrans  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Neste trabalho, objetivou-se estudar o efeito do período de armazenamento no teor de lipídios de juvenis do segundo estádio (J2) de M. incognita com endósporos de P. penetrans na infectividade e reprodução em tomateiro. Suspensões de M. incognita contendo ou não endósporos de P. penetrans aderidos à [...] cutícula foram armazenadas por 0, 3, 6, 9 e 12 dias, a 28ºC. Após cada período de estocagem, determinou-se a concentração de lipídios neutros corporais por meio da análise de imagem dos J2 coloridos com o corante "Oil Red O". Em seguida, 1.000 J2 foram inoculados em mudas de tomateiros. Após 28 dias, avaliou-se o número de fêmeas parasitadas, número de endósporos/fêmea, número de galhas, massas de ovos e de ovos/g de raiz. O teor de lipídio dos J2 reduziu-se com o aumento do período de estocagem. Porém, maiores perdas ocorreram nos J2 sem endósporos de P. penetrans. A proporção entre as perdas dos J2 com e sem P. penetrans foi pequena e decrescente com o período de estocagem. Entretanto, a desproporção foi grande entre 3 e 6 dias de armazenamento dos J2 com e sem P. penetrans com relação aos parâmetros reprodução e número de galhas, indicando consumo de fontes alternativas ao lipí dio neutro de energia p elo J2 parasitado. Mas o período de armazenamento sempre reduziu a reprodução e número de galhas formadas em tomateiros por J2 com e sem P. penetrans. A perda dessas fontes de energia, ao que tudo indica, leva muitos J2 a morrer antes de chegar ao estádio adulto, pois o número de fêmeas parasitadas reduz-se com o armazenamento, além de propiciar menor produção de endósporos por fêmea. O J2 parasitado por P. penetrans necessita encontrar rapidamente a raiz e não permanecer no solo por mais de 6 dias antes de parasitar a planta. Abstract in english This work aimed to study the effect of storage period on lipid content of second stage juveniles (J2) of M. incognita with endospores of P. penetrans on infectivity and reproduction in tomato. Suspensions of M. incognita containing or not endospores of P. penetrans adhered to cuticle were stored by [...] 0, 3, 6, 9 and 12 days at 28ºC. After each storage period, the concentration of neutral lipids in the body of J2 was determined by image analysis of J2 stained with "Oil Red O". After that, 1.000 J2 were inoculated in tomato seedlings. After 28 days, the number of infected females, number of endospores per females, number of galls, number of egg masses and number of eggs per gram of root were evaluated. The lipid content of J2 reduced with the increase of storage period. However, greater lost occurred on J2 without endospores of P. penetrans. The ratio between J2 lipid losses with and without P. penetrans was small and decreased with storage period. However, the ratio between J2 with and without P. penetrans was greatest between 3 and 6 days of storage in relation to parameters reproduction and number of galls, indicating consumption of alternative energy sources others than neutral lipids by infected J2. But the storage period always reduced the reproduction and number of galls formed in tomatoes by J2 with and without P. penetrans. The loss of those energy sources indicate that many J2 dye before adult stage, because the number of parasitized females reduced with storage, besides of smaller endospores production per female. The J2 infested by P. penetrans needs to find the root quickly and should not stay in the soil for more than 6 days before parasitizing the plant.

Fernando da Silva, Rocha; Vicente Paulo, Campos; Renata da Silva, Canuto; Ricardo Magela de, Souza.

2009-02-01

237

Purification and identification of metabolites produced by Bacillus cereus and B. subtilis active against Meloidogyne exigua, and their in silico interaction with a putative phosphoribosyltransferase from M. incognita  

Scientific Electronic Library Online (English)

Full Text Available Com o objetivo de contribuir para o desenvolvimento de produtos para o controle de Meloidogyne exigua, as bactérias Bacillus cereus e B. subtilis foram cultivadas em meio líquido de cultura para produzirem metabólitos ativos contra este nematoide parasita de plantas. Os fracionamentos dos extratos e [...] m diclorometano dos meios de cultura produziram uracila, 9H-purina e di-idrouracila. Todos os compostos foram ativos contra M. exigua, sendo o último o mais eficiente. Ele apresentou CL50 de 204 µg/mL contra o nematoide, enquanto uma CL50 de 260 µg/mL foi observada para o nematicida comercial carbofuran. Uma busca por complexos proteína-ligante nos quais o ligante fosse estruturalmente similar à di-idrouracila resultou na seleção de fosforibosiltransferases, cujas sequências foram utilizadas em uma busca in silico no genoma de M. incognita por sequência de aminoácidos semelhante. A sequência resultante foi modelada e di-idrouracila e 9H-purina foram inseridos nos sítios ativos desta provável fosforibosiltransferase, resultando em complexos proteína-ligante que foram submetidos a simulações por dinâmica molecular. Cálculos das energias livres de ligação destes complexos revelaram que a constante de dissociação de di-idrouracila e 9H-purina da enzima é da ordem de 8,3 x 10-7 e 1,6 x 10-6 M, respectivamente. Consequentemente, estas substâncias e a provável fosforibosiltransferase podem ser de grande utilidade para o desenvolvimento de novos produtos para o controle de M. exigua. Abstract in english To contribute to the development of products to control Meloidogyne exigua, the bacteria Bacillus cereus and B. subtilis were cultivated in liquid medium to produce metabolites active against this plant-parasitic nematode. Fractionation of the crude dichloromethane extracts obtained from the culture [...] s afforded uracil, 9H-purine and dihydrouracil. All compounds were active against M. exigua, the latter being the most efficient. This substance presented a LC50 of 204 µg/mL against the nematode, while a LC50 of 260 µg/mL was observed for the commercial nematicide carbofuran. A search for protein-ligand complexes in which the ligands were structurally similar to dihydrouracil resulted in the selection of phosphoribosyltransferases, the sequences of which were used in an in silico search in the genome of M. incognita for a similar sequence of amino acids. The resulting sequence was modelled and dihydrouracil and 9H-purine were inserted in the active site of this putative phosphoribosyltransferase resulting in protein-ligand complexes that underwent molecular dynamics simulations. Calculation of the binding free-energies of these complexes revealed that the dissociation constant of dihydrouracil and 9H-purine to this protein is around 8.3 x 10-7 and 1.6 x 10-6 M, respectively. Consequently, these substances and the putative phosphoribosyltransferase are promising for the development of new products to control M. exigua.

DENILSON F., OLIVEIRA; HELVÉCIO M. DOS, SANTOS JÚNIOR; ALEXANDRO S., NUNES; VICENTE P., CAMPOS; RENATA S.C. DE, PINHO; GIOVANNA C., GAJO.

2014-06-01

238

Integrated Management of Meloidogyne incognita Infecting Eggplant by Certain Organic Amendments, Bacillus thuringiensis and Oxamyl with Reference to N P K and Total Chlorophyll Status  

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Full Text Available Greenhouse experiment on the impact of horse manure or sesame-oil-cake or Bacillus thuringiensis singly and/or integrated with oxamyl on Meloidogyne incognita infecting eggplant cv. Black long at 25±5°C, revealed that all tested treatments obviously improved plant growth response and reduced nematode development. Among the tested components, B. thuringiensis applied alone or mixed with oxamyl gave the highest percentage of increase in plant growth parameters i.e., plant fresh weight and shoot dry weight with values of 105.9 and 85.8% and 127.8 and 107.5%, respectively, as well as the lowest percent reduction of nematode developmental criteria. Moreover, in concomitant application of horse manure plus oxamyl appeared to be the best treatment in suppressing nematode development and improving plant growth parameters, followed by sesame oil-cake plus oxamyl, then sesame oil-cake and horse manure alone. Meanwhile, length of shoot and number of leaves were positively affected by the tested materials either when applied singly or integrated with oxamyl as compared to nematode alone. Regarding N, P and K status in shoots of eggplant, their concentrations were remarkably reduced by nematode infection. Moreover, single application of any organic amendment or bacterium or oxamyl achieved the highest concentration of N, P and K, whereas the concomitant application of horse manure plus oxamyl showed the highest concentration of phosphorus with value of 0.56 ppm. In addition, the previous treatments obviously decreased the total chlorophyll content of eggplant shoot, whereas nematode infection alone recorded the highest increase percentage for this plant parameter with value of 51.3%.

A.G. El-Sherif

2007-01-01

239

In vitro and foliar spray evaluation of Verbena officinalis (L., Erythrina mulungu (Mart. ex Benth., Quassia amara (L., Bidens pilosa (L. and Plantago lanceolata (L., extracts on Meloidogyne incognita (Kofoid & White, 1919 Chitwood, 1949 Evaluación in vitro y aplicación foliar de Verbena officinalis (L., Erythrina mulungu (Mart. ex Benth., Quassia amara (L., Bidens pilosa (L. y Plantago lanceolata (L., sobre Meloidogyne incognita (Kofoid & White, 1919 Chitwood, 1949  

Directory of Open Access Journals (Sweden)

Full Text Available This study aimed to evaluate the efficiency of aqueous extracts of five species of medicinal plant, Verbena officinalis (L., Erythrina mulungu (Mart. ex Benth., Quassia amara (L., Bidens pilosa (L. and Plantago lanceolata (L. in vitro, and sprayed on tomato plants for the control of Meloidogyne incognita. In vitro experiments were conducted in growth chambers in acrylic ELISA plates. The treatments were doses of 0, 10, 20, 30, 40 and 50 g • L-1 of different aqueous extracts. On the sixteenth day the number of second stage juveniles (J2 hatched per treatment was evaluated. The results showed that aqueous extracts of V. officinalis, E. mulungu, Q. amara, B. pilosa and P. lanceolata, reduced the hatching of M. incognita, with the aqueous extract of P. lanceolata showing up to 100% reduction in hatching. The in vivo assay was conducted in a greenhouse. For this, four sprays of different extracts were applied to tomato shoots. According to the results of this test, none of the extracts were efficient at controlling M. incognita through foliar spraying. The efficiency of these extracts to control plant parasitic nematodes during in vivo tests should not be disregarded, however, further studies should be conducted to test different methods of application, doses or methods of extracting the active principles.El objetivo del estudio fue evaluar la eficacia de los extractos acuosos de cinco especies de plantas medicinales, Verbena officinalis (L., Erythrina mulungu (Mart. ex Benth., Quassia amara (L., Bidens pilosa (L. y Plantago lanceolata (L. in vitro, y se pulverizaron en las plantas de tomates para el control de Meloidogyne incognita. Los experimentos in vitro fueron realizados en cámaras de crecimiento en placas de ELISA de tipo acrílico. Los tratamientos fueron dosis de 0,10, 20, 30, 40 y 50 g • L-1 de diferentes extractos acuosos. En el día dieciséis se evaluó el número de juveniles segunda etapa (J2nacidos por tratamiento. Los resultados mostraron que los extractos acuosos de V. officinalis, E. mulungu, Q. amara, B. pilosa y P. lanceolata reducen la eclosión de los juveniles de M. incognita, y el extracto acuoso de P. lanceolata mostró hasta 100% de reducción de la tasa de eclosión. El ensayo in vivo se realizó en un invernadero, y para ello, había cuatro pulverizaciones de diferentes extractos en los brotes de tomate. Según los resultados de esta prueba, ninguno de los extractos por pulverización foliar era eficaz en el control de M. incognita. Sin embargo, no se debe descartar la eficiencia de estos extractos en el control de nematodos parásitos de plantas, pero más estudios se llevan a cabo utilizando diferentes métodos de aplicación, las dosis o métodos de extracción de los principios activos de los extractos.

Milena A Ferrari Mateus

2013-04-01

240

Potential of Leguminous Cover Crops in Management of a Mixed Population of Root-knot Nematodes (Meloidogyne spp.)  

OpenAIRE

Root-knot nematode is an important pest in agricultural production worldwide. Crop rotation is the only management strategy in some production systems, especially for resource poor farmers in developing countries. A series of experiments was conducted in the laboratory with several leguminous cover crops to investigate their potential for managing a mixture of root-knot nematodes (Meloidogyne arenaria, M. incognita, M. javanica). The root-knot nematode mixture failed to multiply on Mucuna pru...

Osei, Kingsley; Gowen, Simon R.; Pembroke, Barbara; Brandenburg, Rick L.; Jordan, David L.

2010-01-01

241

Integrated Management of Meloidogyne incognita Infecting Soybean by Certain Organic Amendments, Bacillus thuringiensis, Trichoderma harzianum and Oxamyl with Reference to NPK and Total Chlorophyll Statuus  

Directory of Open Access Journals (Sweden)

Full Text Available The integrated control of M. incognita infecting soybean cv. Giza 21 using camel manure, dried leaf powder of marigold, Trichoderma harzianum 100% filtrate, Bacillus thringiensis singly or in combination with oxamyl under greenhouse condition (22±3°C indicated that the concomitant treatments obviously gave better results than single ones did. Moreover, B. thringiensis plus oxamyl at half dose each surpassed all other tested materials in percentage increase of total plant fresh and shoot dry weights (99 and 88 %, respectively, followed by T. harzianum filtrate plus oxamyl (95 and 61% in this respect. On the other hand, pots received T. harzianum filtrate plus oxamyl ranked first in suppressing final nematode population (90%, root galling (65% and eggmass numbers (62.79%, followed by B.t. plus oxamyl, marigold powder +oxamyl and then camel manure + oxamyl, where their reduction percentage values amounted to 88.7, 62.5 and 61%; 88.5, 59.87 and 58.9% and 67, 50.5 and 52.97%, respectively. Of the tested singly applications, T. harzianum filtrate showed the best results in improving plant growth and suppressing nematode development criteria, followed by B.t., whereas, marigold powder and camel manure achieved the lowest values in this respect comparing to nematode alone. Regarding the N, P and K concentrations in leaves of soybean plants inoculated with M. incognita treated with certain organic matters or fungal filtrate or bacterium alone or mixed with oxamyl, they were obviously enhanced by all tested materials whereas the opposite results was recorded for total chlorophyll content comparing to nematode alone.

A.G. El-Sherif

2009-01-01

242

Efecto de la biodesinfección con residuos de nim (Azadirachta indica A. Juss) sobre población de Meloidogyne spp. en suelo / Effect of neem (Azadirachta indica A. Juss) Waste on Meloidogyne spp. population in soil  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish Se evaluó el efecto de residuos del proceso industrial de obtención de plaguicidas del nim (Azadirachta indica A. Juss), provenientes de la Fábrica «Rosa E. Simeón», Güines (Mayabeque, Cuba) sobre una población de Meloidogyne spp. El experimento se desarrolló en condiciones semicontroladas, utilizan [...] do suelo no estéril, con nivel inicial de Meloidognye spp. de 0,5 juveniles de segundo estadio (J2)-huevos.g de suelo-1. Se establecieron ocho tratamientos, cuatro de los cuales se inocularon adicionalmente con 5 J2-huevos.g de suelo-1 de Meloidogyne incognita (Kofoid y White) Chitwood y se empleó como hospedante tomate (Solanum lycopersicom L. var. Campbell 28). Se aplicaron tres dosis de residuos 138,47 g.maceta-1, 60,28 g.maceta-1 y 40,19 g.maceta-1 (lo que equivale a aplicar 4, 3 y 2 kg.m2-1 respectivamente). A los 50 días se determinó el Índice de Agallamiento (IA) (0 a 5 grados), longitud del tallo y masa fresca de raíces. Las mayores poblaciones de nematodos se produjeron en el tratamiento testigo (sin nim) (IA =5), exhibiendo diferencias significativas con aquellos donde se aplicaron los residuos, destacándose el tratamiento con 138,47 g.maceta-1 (equivalente a 4 kg.m2-1) que mostró un IA de 2,4. Los resultados mostraron la potencialidad que posee este desecho para el manejo de nematodos y la necesidad de estudiar su efecto sobre las plantas y las propiedades físico, químicas y biota del suelo. Abstract in english The effect of the waste from the industrial production of neem-based pesticides (Azadirachta indica A. Juss) originated in «Rosa Elena Simeón» factory in Güines (Mayabeque, Cuba) on Meloidogyne spp. population was evaluated, The experiment was carried out under semi-controlled conditions, using non [...] sterilized soil with an initial level of Meloidogyne spp. of 0,5 juveniles-eggs.g of soil-1. Eight treatments were set up; four of them were additionally inoculated with 5 juveniles-eggs.g of soil-1 of Meloidogyen incognita (Kofoid and White) Chitwood. Tomato (Solanum lycopersicom L. var. Campbell 28) was used as host. Three doses of the waste (138,47g.pot-1, 60,288 g.pot-1 and 40,19 g.pot¹; -equivalent to 4, 3 and 2 kg.m2-1 respectively) were applied. After fifty days, root knot galling index (GI) (0 to 5 grades), stem length and fresh weight of roots were evaluated. The highest populations appeared in the control treatment (without neem) (GI=5), which differed significantly from the treatments with the waste, where the best behavior was observed with 138,47 g.pot-1 (equivalent to 4 kg.m2-1) with a GI of 2,4. The results showed the potential of this waste for the management of plant parasitic nematodes and the need for studies on the effect upon the plants and the physical-chemical properties and biota of soils.

Mayra G, Rodríguez; Lucila, Gómez; Dainé, Hernández-Ochandía; R, Enrique; Ileana, Miranda; Oriela, Pino; I, Castro-Lizazo; L. Carolina, Rosales; Luisa, Díaz-Viruliche.

2012-12-01

243

In vitro and foliar spray evaluation of Verbena officinalis (L.), Erythrina mulungu (Mart. ex Benth.), Quassia amara (L.), Bidens pilosa (L.) and Plantago lanceolata (L.), extracts on Meloidogyne incognita (Kofoid & White, 1919) Chitwood, 1949 / Evaluación in vitro y aplicación foliar de Verbena officinalis (L.), Erythrina mulungu (Mart. ex Benth.), Quassia amara (L.), Bidens pilosa (L.) y Plantago lanceolata (L.), sobre Meloidogyne incognita (Kofoid & White, 1919) Chitwood, 1949  

Scientific Electronic Library Online (English)

Full Text Available El objetivo del estudio fue evaluar la eficacia de los extractos acuosos de cinco especies de plantas medicinales, Verbena officinalis (L.), Erythrina mulungu (Mart. ex Benth.), Quassia amara (L.), Bidens pilosa (L.) y Plantago lanceolata (L.) in vitro, y se pulverizaron en las plantas de tomates pa [...] ra el control de Meloidogyne incognita. Los experimentos in vitro fueron realizados en cámaras de crecimiento en placas de ELISA de tipo acrílico. Los tratamientos fueron dosis de 0,10, 20, 30, 40 y 50 g • L-1 de diferentes extractos acuosos. En el día dieciséis se evaluó el número de juveniles segunda etapa (J2)nacidos por tratamiento. Los resultados mostraron que los extractos acuosos de V. officinalis, E. mulungu, Q. amara, B. pilosa y P. lanceolata reducen la eclosión de los juveniles de M. incognita, y el extracto acuoso de P. lanceolata mostró hasta 100% de reducción de la tasa de eclosión. El ensayo in vivo se realizó en un invernadero, y para ello, había cuatro pulverizaciones de diferentes extractos en los brotes de tomate. Según los resultados de esta prueba, ninguno de los extractos por pulverización foliar era eficaz en el control de M. incognita. Sin embargo, no se debe descartar la eficiencia de estos extractos en el control de nematodos parásitos de plantas, pero más estudios se llevan a cabo utilizando diferentes métodos de aplicación, las dosis o métodos de extracción de los principios activos de los extractos. Abstract in english This study aimed to evaluate the efficiency of aqueous extracts of five species of medicinal plant, Verbena officinalis (L.), Erythrina mulungu (Mart. ex Benth.), Quassia amara (L.), Bidens pilosa (L.) and Plantago lanceolata (L.) in vitro, and sprayed on tomato plants for the control of Meloidogyne [...] incognita. In vitro experiments were conducted in growth chambers in acrylic ELISA plates. The treatments were doses of 0, 10, 20, 30, 40 and 50 g • L-1 of different aqueous extracts. On the sixteenth day the number of second stage juveniles (J2) hatched per treatment was evaluated. The results showed that aqueous extracts of V. officinalis, E. mulungu, Q. amara, B. pilosa and P. lanceolata, reduced the hatching of M. incognita, with the aqueous extract of P. lanceolata showing up to 100% reduction in hatching. The in vivo assay was conducted in a greenhouse. For this, four sprays of different extracts were applied to tomato shoots. According to the results of this test, none of the extracts were efficient at controlling M. incognita through foliar spraying. The efficiency of these extracts to control plant parasitic nematodes during in vivo tests should not be disregarded, however, further studies should be conducted to test different methods of application, doses or methods of extracting the active principles.

Milena A, Ferrari Mateus; Cacilda M, Duarte Rios Faria¹; Renato V, Botelho; Rosangela, Dallemole-Giaretta; Silvana G, Martins Ferreira; Welton L, Zaluski.

2013-04-01

244

Influence of Alfalfa Plant Growth on the Multiplication Rates and Ceiling Population Density of Meloidogyne hapla  

OpenAIRE

The rates of reproduction and multiplication of Meloidogyne hapla decreased as a result of self-regulatory, density-dependent processes with time and nematode population increase in the soil and roots of Medicago sativa cv. Cuf 101. Juvenile, egg, and mature female population densities increased at a maximum rate until damage to the host resulted in alfalfa yield reductions. Temporal differences in multiplication and reproduction rates of M. hapla were observed to be a function of initial pop...

Noling, J. W.; Ferris, H.

1986-01-01

245

Effects of Cropping Sequences on Population Densities of Meloidogyne hapla and Carrot Yield in Organic Soil  

OpenAIRE

The influence of various cropping sequences on population densities of Meloidogyne hapla and carrot yield was studied in organic soil under microplot-and field conditions. Spinach, radish, barley, oat, and wheat were poor or nonhosts for M. hapla. Population densities of M. hapla were maintained or increased on cabbage, celery, lettuce, leek, marigold, and potato. Marketable percent-age and root weight of carrots were greater following spinach, oat, radish, and fallow-onion than those followi...

Be?lair, Guy

1992-01-01

246

Differential Reaction of Alfalfa Cultivars to Meloidogyne hapla and M. chitwoodi Populations  

OpenAIRE

Meloidogyne hapla reproduced and suppressed growth (P < 0.05) of susceptible Lahontan and Moapa alfalfa at 15, 20, and 25 C. At 30 C, resistant Nevada Syn XX lost resistance to M. hapla. M. hapla invaded and reproduced on Rhizobium meliloti nodules of Lahontan and Moapa, inducing giant cell formation and structural disorder of vascular bundles of nodules without disrupting bacteroids. At 15, 20, and 25 C a M. chitwoodi population from Utah reproduced on Lahontan, Moapa, and Nevada Syn XX alfa...

Griffin, G. D.; Inserra, R. N.; Vovlas, N.; Sisson, D. V.

1986-01-01

247

Morphological and Molecular Characterization of Meloidogyne mayaguensis Isolates from Florida  

OpenAIRE

The discovery of Meloidogyne mayaguensis is confirmed in Florida; this is the first report for the continental United States. Meloidogyne mayaguensis is a virulent species that can reproduce on host cultivars bred for nematode resistance. The perineal patterns of M. mayaguensis isolates from Florida show morphological variability and often are similar to M. incognita. Useful morphological characters for the separation of M. mayaguensis from M. incognita from Florida are the male stylet length...

Brito, J.; Powers, T. O.; Mullin, P. G.; Inserra, R. N.; Dickson, D. W.

2004-01-01

248

Potential of Leguminous Cover Crops in Management of a Mixed Population of Root-knot Nematodes (Meloidogyne spp.).  

Science.gov (United States)

Root-knot nematode is an important pest in agricultural production worldwide. Crop rotation is the only management strategy in some production systems, especially for resource poor farmers in developing countries. A series of experiments was conducted in the laboratory with several leguminous cover crops to investigate their potential for managing a mixture of root-knot nematodes (Meloidogyne arenaria, M. incognita, M. javanica). The root-knot nematode mixture failed to multiply on Mucuna pruriens and Crotalaria spectabilis but on Dolichos lablab the population increased more than 2- fold when inoculated with 500 and 1,000 nematodes per plant. There was no root-galling on M. pruriens and C. spectabilis but the gall rating was noted on D. lablab. Greater mortality of juvenile root-knot nematodes occurred when exposed to eluants of roots and leaves of leguminous crops than those of tomato; 48.7% of juveniles died after 72 h exposure to root eluant of C. spectabilis. The leaf eluant of D. lablab was toxic to nematodes but the root eluant was not. Thus, different parts of a botanical contain different active ingredients or different concentrations of the same active ingredient. The numbers of root-knot nematode eggs that hatched in root exudates of M. pruriens and C. spectabilis were significantly lower (20% and 26%) than in distilled water, tomato and P. vulgaris root exudates (83%, 72% and 89%) respectively. Tomato lacks nematotoxic compounds found in M. pruriens and C. spectabilis. Three months after inoculating plants with 1,000 root-knot nematode juveniles the populations in pots with M. pruriens, C. spectabilis and C. retusa had been reduced by approximately 79%, 85% and 86% respectively; compared with an increase of 262% nematodes in pots with Phaseolus vulgaris. There was significant reduction of 90% nematodes in fallow pots with no growing plant. The results from this study demonstrate that some leguminous species contain compounds that either kill root-knot nematodes or interfere with hatching and affect their capacity to invade and develop within their roots. M. pruriens, C. spectabilis and C. retusa could be used with effect to decrease a mixed field populations of root-knot nematodes. PMID:22736854

Osei, Kingsley; Gowen, Simon R; Pembroke, Barbara; Brandenburg, Rick L; Jordan, David L

2010-09-01

249

Comparative and Evolutionary Analyses of Meloidogyne spp. Based on Mitochondrial Genome Sequences.  

Science.gov (United States)

Molecular taxonomy and evolution of nematodes have been recently the focus of several studies. Mitochondrial sequences were proposed as an alternative for precise identification of Meloidogyne species, to study intraspecific variability and to follow maternal lineages. We characterized the mitochondrial genomes (mtDNAs) of the root knot nematodes M. floridensis, M. hapla and M. incognita. These were AT rich (81-83%) and highly compact, encoding 12 proteins, 2 rRNAs, and 22 tRNAs. Comparisons with published mtDNAs of M. chitwoodi, M. incognita (another strain) and M. graminicola revealed that they share protein and rRNA gene order but differ in the order of tRNAs. The mtDNAs of M. floridensis and M. incognita were strikingly similar (97-100% identity for all coding regions). In contrast, M. floridensis, M. chitwoodi, M. hapla and M. graminicola showed 65-84% nucleotide identity for coding regions. Variable mitochondrial sequences are potentially useful for evolutionary and taxonomic studies. We developed a molecular taxonomic marker by sequencing a highly-variable ~2 kb mitochondrial region, nad5-cox1, from 36 populations of root-knot nematodes to elucidate relationships within the genus Meloidogyne. Isolates of five species formed monophyletic groups and showed little intraspecific variability. We also present a thorough analysis of the mitochondrial region cox2-rrnS. Phylogenies based on either mitochondrial region had good discrimination power but could not discriminate between M. arenaria, M. incognita and M. floridensis. PMID:25799071

García, Laura Evangelina; Sánchez-Puerta, M Virginia

2015-01-01

250

Native-plant hosts of Meloidogyne spp. from Western Paraná, Brazil  

OpenAIRE

The present study was focused on the parasitism of Meloidogyne species on the roots of native nursery plants from the Atlantic forest. Native plants were selected from a commercial nursery in Western Paraná, searching for the natural infection of Meloidogyne. Also, the seeds of native plants were cultivated in sterile soil and inoculated with M. incognita. In both the experiments, the number of galls and number of eggs and J2 per root, allied to the reproduction factor of M. incognita on eac...

Antes, Vanessa A.; Comerlato, Anna P.; Adílson Ricken Schuelter; Carneiro, Regina M. D. G.; Cleber Furlanetto

2012-01-01

251

Relationship Between Crop Losses and Initial Population Densities of Meloidogyne arenaria in Winter-Grown Oriental Melon in Korea  

OpenAIRE

To determine the economic threshold level, oriental melon (Cucumis melo L. cv. Geumssaragi-euncheon) grafted on Shintozoa (Cucurbita maxima × Cu. moschata) was planted in plots (2 × 3 m) under a plastic film in February with a range of initial population densities (Pi) of Meloidogyne arenaria. The relationships of early, late, and total yield to Pi measured in September and January were adequately described by both linear regression and the Seinhorst damage model. Initial nematode densities...

Kim, D. G.; Ferris, H.

2002-01-01

252

Reprodução de Meloidogyne spp. em porta-enxertos e híbridos de pepino / Reproduction of Meloidogyne spp. in rootstocks and cucumber hybrids  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese A enxertia é uma técnica alternativa frequentemente recomendada para a cultura do pepino em áreas infestadas com nematóides das galhas. O presente trabalho teve como objetivo determinar o fator de reprodução de Meloidogyne javanica e de Meloidogyne incognita raça 2 em seis porta-enxertos para pepino [...] (abóbora 'Menina Brasileira', moranga 'Exposição', 'Shelper', 'Tetsukabuto', 'B8-A Tetsukabuto' e 'Excite Ikki') e quatro híbridos de pepino (Cucumis sativus) tipo japonês ('Yoshinari', 'Kouki', 'Taisho' e 'Tsuyataro'). Foram conduzidos dois experimentos em casa-de-vegetação, um com cada espécie do nematóide, sendo cada parcela constituída de uma planta mantida em vaso contendo 2 litros de solo autoclavado. Nove dias após transplante, cada planta foi inoculada com 5.000 ovos e juvenis de segundo estádio (população inicial - Pi) de M. javanica ou M. incognita raça 2. Tomateiros 'Rutgers' foram utilizados como padrão de viabilidade do inóculo, em ambos os experimentos. O delineamento experimental foi inteiramente casualizado com cinco repetições por tratamento. Sessenta dias após a inoculação, cada planta foi avaliada, quanto ao peso fresco da raiz, número total de nematóides presentes no solo e na raiz (população final - Pf), número de nematóides/g de raiz e fator de reprodução de ambas as espécies de Meloidogyne (FR=Pf/Pi). Todos os porta-enxertos e híbridos de pepino testados apresentaram fatores de reprodução superiores a um, proporcionando a multiplicação de M. javanica e de M. incognita raça 2, porém, os valores nos híbridos de pepino foram superiores aos dos porta-enxertos. Abstract in english Grafting is an alternative technique often recommended for the cucumber crop in root-knot nematodes infested areas. This study aimed to determine the reproduction factor of Meloidogyne javanica and M. incognita race 2 on six rootstocks for cucumber (squash 'Menina Brasileira, pumpkim 'Exposição', 'S [...] helper', 'Tetsukabuto', 'B8-A Tetsukabuto' and 'Excite Ikki') and four cucumber (Cucumis sativus) Japanese type hybrids of ('Yoshinari', 'Kouki', 'Taisho' and 'Tsuyataro'). Two experiments were carried out in greenhouse, each one with a nematode specie. Each plot consisted of one plant per pot containing 2 liters of autoclaved soil. Nine days after the seedlings transplantation, each plant was inoculated with 5,000 eggs and second-stage juveniles (initial population - Pi) of M. javanica or M. incognita race 2. 'Rutgers' tomatoes were used as a standard for inoculum viability in both experiments. The experimental design was completely randomized with five replicates per treatment. Sixty days after inoculated, each plant was evaluated, when root fresh weight, total number of nematodes in the soil and in the roots (final population - Pf), nematodes number per gram of root and the reproduction factor of both Meloidogyne species (FR=Pf/Pi) were determined. All rootstocks and cucumber hybrids allowed the M. javanica and M. incognita race 2 multiplication, but, generally, reproduction factor values were greater in cucumbers than in rootstocks.

Silvia Renata S, Wilcken; Juliana MO, Rosa; Andréa RO, Higuti; Maria José de M, Garcia; Antonio Ismael Inácio, Cardoso.

2010-03-01

253

Reprodução de Meloidogyne spp. em porta-enxertos e híbridos de pepino Reproduction of Meloidogyne spp. in rootstocks and cucumber hybrids  

Directory of Open Access Journals (Sweden)

Full Text Available A enxertia é uma técnica alternativa frequentemente recomendada para a cultura do pepino em áreas infestadas com nematóides das galhas. O presente trabalho teve como objetivo determinar o fator de reprodução de Meloidogyne javanica e de Meloidogyne incognita raça 2 em seis porta-enxertos para pepino (abóbora 'Menina Brasileira', moranga 'Exposição', 'Shelper', 'Tetsukabuto', 'B8-A Tetsukabuto' e 'Excite Ikki' e quatro híbridos de pepino (Cucumis sativus tipo japonês ('Yoshinari', 'Kouki', 'Taisho' e 'Tsuyataro'. Foram conduzidos dois experimentos em casa-de-vegetação, um com cada espécie do nematóide, sendo cada parcela constituída de uma planta mantida em vaso contendo 2 litros de solo autoclavado. Nove dias após transplante, cada planta foi inoculada com 5.000 ovos e juvenis de segundo estádio (população inicial - Pi de M. javanica ou M. incognita raça 2. Tomateiros 'Rutgers' foram utilizados como padrão de viabilidade do inóculo, em ambos os experimentos. O delineamento experimental foi inteiramente casualizado com cinco repetições por tratamento. Sessenta dias após a inoculação, cada planta foi avaliada, quanto ao peso fresco da raiz, número total de nematóides presentes no solo e na raiz (população final - Pf, número de nematóides/g de raiz e fator de reprodução de ambas as espécies de Meloidogyne (FR=Pf/Pi. Todos os porta-enxertos e híbridos de pepino testados apresentaram fatores de reprodução superiores a um, proporcionando a multiplicação de M. javanica e de M. incognita raça 2, porém, os valores nos híbridos de pepino foram superiores aos dos porta-enxertos.Grafting is an alternative technique often recommended for the cucumber crop in root-knot nematodes infested areas. This study aimed to determine the reproduction factor of Meloidogyne javanica and M. incognita race 2 on six rootstocks for cucumber (squash 'Menina Brasileira, pumpkim 'Exposição', 'Shelper', 'Tetsukabuto', 'B8-A Tetsukabuto' and 'Excite Ikki' and four cucumber (Cucumis sativus Japanese type hybrids of ('Yoshinari', 'Kouki', 'Taisho' and 'Tsuyataro'. Two experiments were carried out in greenhouse, each one with a nematode specie. Each plot consisted of one plant per pot containing 2 liters of autoclaved soil. Nine days after the seedlings transplantation, each plant was inoculated with 5,000 eggs and second-stage juveniles (initial population - Pi of M. javanica or M. incognita race 2. 'Rutgers' tomatoes were used as a standard for inoculum viability in both experiments. The experimental design was completely randomized with five replicates per treatment. Sixty days after inoculated, each plant was evaluated, when root fresh weight, total number of nematodes in the soil and in the roots (final population - Pf, nematodes number per gram of root and the reproduction factor of both Meloidogyne species (FR=Pf/Pi were determined. All rootstocks and cucumber hybrids allowed the M. javanica and M. incognita race 2 multiplication, but, generally, reproduction factor values were greater in cucumbers than in rootstocks.

Silvia Renata S Wilcken

2010-03-01

254

Native-plant hosts of Meloidogyne spp. from Western Paraná, Brazil  

Directory of Open Access Journals (Sweden)

Full Text Available The present study was focused on the parasitism of Meloidogyne species on the roots of native nursery plants from the Atlantic forest. Native plants were selected from a commercial nursery in Western Paraná, searching for the natural infection of Meloidogyne. Also, the seeds of native plants were cultivated in sterile soil and inoculated with M. incognita. In both the experiments, the number of galls and number of eggs and J2 per root, allied to the reproduction factor of M. incognita on each inoculated plant were assessed. Natural infection by M. javanica was found on Cordia ecalyculata, Citharexyllum myrianthum and Aspidosperma subincanum and by M. incognita on Croton urucurana, Lonchocarpus muehlbergianus, Tabebuia impetiginosa and T. serratifolia. Meloidogyne incognita induced galls formation on Genipa americana, Schinus terebinthifolius and Rollinia mucosa after inoculation, which suggested that those plants could host this nematode in natural biomes. Nursery soil should be disinfested before seeding the native forest plants for reforestation purposes

Vanessa A. Antes

2012-04-01

255

Meloidogyne mayaguensis RAMMAH Y HIRSCHMANN, PLAGA EMERGENTE PARA LA AGRICULTURA TROPICAL Y SUBTROPICAL / Meloidogyne mayaguensis RAMMAH Y HIRSCHMANN, EMERGENT PEST FOR TROPICAL AND SUBTROPICAL AGRICULTURE  

Scientific Electronic Library Online (English)

Full Text Available Meloidogyne mayaguensis Rammah y Hirschmann, constituye una importante plaga en países de la zona tropical y subtropical, donde parasita de manera natural más de 30 especies de diferentes plantas de cultivo como guayaba (Psidium guajava), cafeto (Coffea spp.), hortalizas, ornamentales y arvenses. Su [...] distribución ha ocurrido relativamente rápido debido a factores antropogénicos y la mayor preocupación con esta especie es su capacidad para parasitar y reproducirse en plantas con resistencia a Meloidogyne spp. Esta especie presenta alta variabilidad en la morfología de su patrón perineal, por lo que es recomendable, para su identificación, el uso de elementos complementarios como los que ofrecen los perfiles de esterasas. Esta especie puede hallarse en poblaciones concomitantes junto a Meloidogyne incognita, Meloidogyne arenaria y Meloidogyne javanica, haciendo más complejo su diagnóstico y manejo. Entre las regulaciones empleadas para mitigar su efecto negativo se encuentran, la implementación de medidas de cuarentena interna y el uso de Cadusafos y Abamectina, con resultados variables. De igual modo, grupos de investigación en África y América han evaluado extractos de Crotalaria spp. y agentes de control biológico (Arthrobotrys spp.), entre otras tácticas. M. mayaguensis se considera una de las especies más peligrosas del género, su detección, correcta identificación y contención en las áreas donde aparece constituyen uno de los retos más importantes de las autoridades sanitarias en los países donde ha sido encontrada, para los cuales la información oportuna y capacitación efectiva de los actores involucrados en esta esfera representa un elemento de vital importancia para el enfrentamiento a esta plaga emergente. Abstract in english Meloidogyne mayaguensis Rammah y Hirschmann, is an important pest in tropical and subtropical countries, because it affects in natural way more than 30 different species like guava (Psidium guajava), coffee (Coffea spp.), vegetables, ornamental plants and weeds. Its distribution has been very fast d [...] ue to anthropogenic factors, and the highest concern about this species is its capacity to infest and reproduce on resistant plants to Meloidogyne spp. This species has a high variability in its perineal pattern morphology; thus the use of complementary elements like the offered by esterase profile is recommended. This specie has been found in mixed population with Meloidogyne incognita, Meloidogyne arenaria and Meloidogyne javanica, making more complex its diagnosis and management. Among the measurements to diminish its negative effect are the implementation of internal quarantine measures and the use of Cadusafos and Abermectine with variable results. In the same way, different research teams from Africa and America have evaluated extracts from Crotalaria spp., biological control agents (Arthrobotrys spp.), among other tactics. M. mayaguensis has been considered one of the most dangerous species of this genus. Its detection, right identification and contention in the areas in which it is found constitute one of the most important challenges for the sanitary authorities in the countries when the species has been reported. The opportune information and the effective training of the staff involved in the phytosanitary area represent a vital element for facing this emergent pest.

Mayra G, Rodríguez; Lucila, Gómez; Belkis, Peteira.

2007-12-01

256

Pathogenicity of Meloidogyne spp. (Tylenchida: Meloidogynidae from Brazil and Central America on two genotypes of Coffea arabica Patogenicidade de Meloidogyne spp. (Tylenchida: Meloidogynidae originárias do Brasil e América Central a dois genótipos de Coffea arabica  

Directory of Open Access Journals (Sweden)

Full Text Available Among the most damaging root-knot nematode species, Meloidogyne exigua, M. paranaensis, M. incognita, M. arabicida, M. izalcoensis and M. mayaguensis are major agronomic constraints in coffee-growing areas in Brazil and other Latin American countries. The resistance reaction to those six species was studied for the H 419-5-4-5-2 progeny, derived from the artificial hybridization between Catuaí Amarelo 'IAC 30' x Timor Hybrid UFV 445-46 selection. The Catuaí Vermelho IAC 144 genotype was used as susceptibility control for Meloidogyne spp. The genotypes were inoculated with 6,000 eggs/plant and the experiment was set up in a completely randomized design, replicated 10 times for each Meloidogyne species and genotype. The evaluation was performed at 240 days after inoculation and the reproduction factor (RF= Final population/6000 was used as the variable to evaluate resistance. M. exigua caused typical rounded galls mostly on new roots, and egg-masses were produced mostly in the cortex under the root epidermis. M. incognita, M. paranaensis and M. arabicida caused swollen roots, peeling and cracking of cortical root tissue. No symptoms were observed for M. mayaguensis. M. izalcoensis induced very small galls, mostly on the extremity of new roots. Egg-masses were produced outside the roots in large quantities. The genotype IAC 144 was susceptible (FR>1.0 to all Meloidogyne spp. studied, except to M. mayaguensis. The nematode isolate used in this experiment seems to be a weak parasite for coffee. The H 419-5-4-5-2 progeny was resistant to M. exigua (FREntre as espécies de nematóides de galhas mais danosas ao cafeeiro, Meloidogyne exigua, M. paranaensis, M. incognita, M. arabicida, M. izalcoensis e M. mayaguensis são as que causam os maiores problemas em áreas de cultivo de café no Brasil e países da América Latina. A reação de resistência a essas seis espécies foi estudada na progênie H 419-5-4-5-2, obtida do cruzamento artificial entre a cultivar Catuaí Amarelo IAC 30 com a seleção de Híbrido de Timor UFV 445-46. As genótipos foram inoculados com 6.000 ovos/planta e o experimento foi conduzido no delineamento inteiramente ao acaso, com 10 repetições para cada espécie de Meloidogyne e cada genótipo de cafeeiro. A avaliação foi realizada 240 dias após a inoculação. O Fator de Reprodução (FR= População Final/6000 foi usado como variável para se avaliar a resistência. M. exigua causou galhas arredondadas típicas, sobretudo nas raízes novas. M. incognita, M. paranaensis e M. arabicida causaram engrossamento nas raízes, descolamento cortical e rachaduras em várias partes do sistema radicular.Nenhum sintoma foi observado para M. mayaguensis. M. izalcoensis causou galhas pequenas, a maioria na extremidade das raízes novas. As massas de ovos foram produzidas externamente e em grande número. O genótipo IAC 144 (testemunha foi suscetível (FR>1.0 a todas espécies de Meloidogyne, exceto a M. mayaguensis. Esse isolado mostrou-se um parasita fraco para o cafeeiro. A progênie H 419-5-4-5-2 foi resistente a M. exigua e M. mayaguensis (FR<1 e suscetível a M. incognita, M. paranaensis, M. arabicida e M. izalcoensis.

Regina M.D.G. Carneiro

2008-08-01

257

Reprodução de Meloidogyne spp. em porta-enxertos e híbridos de pepino Reproduction of Meloidogyne spp. in rootstocks and cucumber hybrids  

OpenAIRE

A enxertia é uma técnica alternativa frequentemente recomendada para a cultura do pepino em áreas infestadas com nematóides das galhas. O presente trabalho teve como objetivo determinar o fator de reprodução de Meloidogyne javanica e de Meloidogyne incognita raça 2 em seis porta-enxertos para pepino (abóbora 'Menina Brasileira', moranga 'Exposição', 'Shelper', 'Tetsukabuto', 'B8-A Tetsukabuto' e 'Excite Ikki') e quatro híbridos de pepino (Cucumis sativus) tipo japonês ('Yoshinari'...

Wilcken, Silvia Renata S.; Mo, Juliana Rosa; Ro, Andre?a Higuti; Garcia, Maria Jose? M.; Antonio Ismael Inácio Cardoso

2010-01-01

258

Influence of Meloidogyne hapla on Alfalfa Yield and Host Population Dynamics  

OpenAIRE

Self-thinning in alfalfa, a dynamic process involving the progressive elimination of the weakest plants, was enhanced by Meloidogyne hapla. Alfalfa stand densities decreased exponentially with time and were reduced 62% (P = 0.05) in the presence of M. hapla. As stand densities decreased over time, mean plant weights increased at a rate 2.59 times faster in the absence of M. hapla. In a stepwise multiple regression analysis, 65% of the total variation in yield could be explained by changes in ...

Noling, J. W.; Ferris, H.

1985-01-01

259

Characterization of Species and Races of the Genus Meloidogyne by DNA Restriction Enzyme Analysis  

OpenAIRE

Total DNA of three species of Meloidogyne spp., including four subspecific races of M. incognita, were digested separately with EcoR I, Cla III, and Hind III and probed with ³²P-labelled total genomic DNA from M. incognita race 1 in Southern hybridizations. Short exposures of Southern blots after Hind III digestion revealed patterns that were useful for separating the species. Race differences were seen after longer exposures. The DNA fragment patterns obtained were scanned with a laser den...

Ga?rate, T.; Robinson, M. P.; Chaco?n, M. R.; Parkhouse, R. M. E.

1991-01-01

260

Host Status of Endophyte-Infected and Noninfected Tall Fescue Grass to Meloidogyne spp.  

OpenAIRE

Tall fescue grass cultivars with or without endophytes were evaluated for their susceptibility to Meloidogyne incognita in the greenhouse. Tall fescue cultivars evaluated included, i) wild-type Jesup (E+, ergot-producing endophyte present), ii) endophyte-free Jesup (E-, no endophyte present), iii) Jesup (Max-Q, non-ergot producing endophyte) and iv) Georgia 5 (E+). Peach was included as the control. Peach supported greater (P ? 0.05) reproduction of M. incognita than all tall fescue cultiva...

Nyczepir, A. P.; Meyer, S. L. F.

2010-01-01

261

Resistance to Meloidogyne spp. in Allohexaploid Wheat Derived from Triticum turgidum and Aegilops squarrosa  

OpenAIRE

Expression of resistance to Meloidogyne incognita and M. javanica from Aegilops squarrosa was studied in a synthetic allohexaploid produced from Triticum turgidum var. durum cv. Produra and Ae. squarrosa G 3489. The reproductive rate of different races of M. incognita and M. javanica, expressed in eggs per gram of fresh root, was low (P < 0.05) on the synthetic allohexaploid and the resistant parent, Ae. squarrosa G 3489, compared with different bread and durum wheat cultivars. Reproduction o...

Kaloshian, I.; Roberts, P. A.; Thomason, I. J.

1989-01-01

262

Meloidogyne partityla on Pecan Isozyme Phenotypes and Other Host  

Science.gov (United States)

Meloidogyne sp. from five pecan (Carya illinoensis) orchards in Texas were distinctive in host range and iszoyme profiles from common species of Meloidogyne but were morphologically congruent with Meloidogyne partityla Kleynhans, a species previously known only in South Africa. In addition to pecan, species of walnut (Juglans hindsii and J. regia) and hickory (C. ovata) also were hosts. No reproduction was observed on 15 other plant species from nine families, including several common hosts of other Meloidogyne spp. Three esterase phenotypes and two malate dehydrogenase phenotypes of M. partityla were identified by polyacrylamide gel electrophoresis. Each of these isozyme phenotypes was distinct from those of the more common species M. arenaria, M. hapla, M. incognita, and M. javanica. PMID:19277175

Starr, J. L.; Tomaszewski, E. K.; Mundo-Ocampo, M.; Baldwin, J. G.

1996-01-01

263

Efeito de isolados de Paecilomyces lilacinus no desenvolvimento de cafezais e na população de Meloidogyne paranaensis / Effect of isolates of Paecilomyces lilacinus on the development of coffee plantations and on the population of Meloidogyne paranaensis  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Com 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) Samson, 1974 se destaca como uma alternativa de controle vantajosa [...] , quer dos pontos de vista ecológico ou econômico. Assim, neste trabalho, objetivou-se avaliar a eficiência de 10 isolados de Paecilomyces lilacinus no controle de Meloidogyne paranaensis em cafeeiro (Coffea arabica L. cv. Icatú), em casa-de-vegetação. No experimento I, as mudas de cafeeiro foram transplantadas em solo onde foram, anteriormente, cultivados tomateiros para multiplicação de M. paranaensis mais 50 g de arroz colonizado com os 10 isolados. No segundo experimento, mudas de cafeeiro foram transplantadas para substrato solo e areia (1:1) juntamente com 50 g de arroz colonizado com os isolados. Em seguida, as mudas foram inoculadas com ± 5000 ovos de M. paranaensis. Nos dois experimentos, após 15 dias procedeu-se aplicação por cobertura de 50 g dos isolados. O delineamento foi inteiramente casualizado com 12 tratamentos. Após 90 dias, foram feitas as avaliações. Os isolados de P. lilacinus não afetaram o diâmetro do caule de cafeeiro. No experimento I, os isolados Pae 22, 24 e 28 promoveram o crescimento dos cafeeiros; todos os isolados reduziram a população de ovos no sistema radicular; e os isolados Pae 3 e 12 reduziram a população de J2 de M. paranaensis no solo. No experimento II, os isolados Pae 03, 10, 12 e 13 favoreceram o crescimento das plantas, mas reduziram o peso fresco do sistema radicular; todos os isolados reduziram a população de J2 no solo; e os isolados Pae 3, 10, 13, 18, 22 e 24 reduziram as malformações causadas por M. paranaensis nas raízes. Abstract in english In 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 ecolo [...] gical 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.

Marina Capparelli, Cadioli; Débora Cristina, Santiago; Arian Derdote de, Oliveira; Vanessa dos Santos, Paes; Giovani de Oliveira, Arieira; Fernando Cesar, Baida.

2009-06-01

264

Efeito de isolados de Paecilomyces lilacinus no desenvolvimento de cafezais e na população de Meloidogyne paranaensis Effect of isolates of Paecilomyces lilacinus on the development of coffee plantations and on the population of Meloidogyne paranaensis  

Directory of Open Access Journals (Sweden)

Full Text Available Com 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 Samson, 1974 se destaca como uma alternativa de controle vantajosa, quer dos pontos de vista ecológico ou econômico. Assim, neste trabalho, objetivou-se avaliar a eficiência de 10 isolados de Paecilomyces lilacinus no controle de Meloidogyne paranaensis em cafeeiro (Coffea arabica L. cv. Icatú, em casa-de-vegetação. No experimento I, as mudas de cafeeiro foram transplantadas em solo onde foram, anteriormente, cultivados tomateiros para multiplicação de M. paranaensis mais 50 g de arroz colonizado com os 10 isolados. No segundo experimento, mudas de cafeeiro foram transplantadas para substrato solo e areia (1:1 juntamente com 50 g de arroz colonizado com os isolados. Em seguida, as mudas foram inoculadas com ± 5000 ovos de M. paranaensis. Nos dois experimentos, após 15 dias procedeu-se aplicação por cobertura de 50 g dos isolados. O delineamento foi inteiramente casualizado com 12 tratamentos. Após 90 dias, foram feitas as avaliações. Os isolados de P. lilacinus não afetaram o diâmetro do caule de cafeeiro. No experimento I, os isolados Pae 22, 24 e 28 promoveram o crescimento dos cafeeiros; todos os isolados reduziram a população de ovos no sistema radicular; e os isolados Pae 3 e 12 reduziram a população de J2 de M. paranaensis no solo. No experimento II, os isolados Pae 03, 10, 12 e 13 favoreceram o crescimento das plantas, mas reduziram o peso fresco do sistema radicular; todos os isolados reduziram a população de J2 no solo; e os isolados Pae 3, 10, 13, 18, 22 e 24 reduziram as malformações causadas por M. paranaensis nas raízes.In 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.

Marina Capparelli Cadioli

2009-06-01

265

Effects of biosolid amendment on populations of Meloidogyne hapla and soils with different textures and pHs.  

Science.gov (United States)

Temperate vegetable and nursery industries face significant challenges in managing Meloidogyne hapla, a plant-parasite for which few resistant cultivars and/or viable alternatives to methyl bromide exist. N-Viro Soil(R) (NVS), an alkaline-stabilized biosolid product, has soil nutrition enrichment capacity and potential for plant-parasitic nematode suppression. In three sets of experiments, we investigated the effects of NVS on M. hapla populations from Rhode Island (RI), Connecticut (CT), New York, Geneva (NYG) and Lyndonville (NYL), and Michigan (MI), and growth of tomato cv 'Rutgers' in five soils commonly used for vegetable and nursery crop production in the Great Lakes Region of the USA. Either 0 (control) or 600 eggs/100 cm(3) of soil per M. hapla population were added in all experiments. In the first set, NVS was applied at rates of 0, 1, 2 and 4 g/100 cm(3) of sandy loam soil (pH 7) and resulted in variable responses on the numbers of nematodes recovered and plant growth at 30 and 90 days (25+/-2 degrees C); however, the 2g NVS treatment consistently increased plant growth. Either 0 or 2 NVS/100 cm(3) were applied to a coarse loamy (pH 4.5) and sandy loam (pH 8, second set of experiments), and muck (pH 5.5), loamy sand (pH 7.1) and sandy loam (pH 7.5, third set of experiments) soils and experiments terminated four weeks after nematode inoculation. Across experiments, the effect of NVS on the M. hapla populations varied. Generally nematode infection decreased plant growth. NVS increased soil pH the most in muck and the least in sandy loam soil. The most consistent interaction effects of NVS*soil, NVS*M. hapla, soil*M. hapla and/or NVS*soil*M. hapla across the experiments indicate that NVS affects M. hapla populations in different ways in different soil types, suggesting that NVS application is likely to be site-specific. These findings further provide basis that may potentially explain reports of variable effects of NVS on nematodes and how future studies may account in furthering our understanding of NVS activities for M. hapla management. PMID:20427181

Mennan, Sevilhan; Melakeberhan, Haddish

2010-09-01

266

Native-plant hosts of Meloidogyne spp. from Western Paraná, Brazil  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The present study was focused on the parasitism of Meloidogyne species on the roots of native nursery plants from the Atlantic forest. Native plants were selected from a commercial nursery in Western Paraná, searching for the natural infection of Meloidogyne. Also, the seeds of native plants were cu [...] ltivated in sterile soil and inoculated with M. incognita. In both the experiments, the number of galls and number of eggs and J2 per root, allied to the reproduction factor of M. incognita on each inoculated plant were assessed. Natural infection by M. javanica was found on Cordia ecalyculata, Citharexyllum myrianthum and Aspidosperma subincanum and by M. incognita on Croton urucurana, Lonchocarpus muehlbergianus, Tabebuia impetiginosa and T. serratifolia. Meloidogyne incognita induced galls formation on Genipa americana, Schinus terebinthifolius and Rollinia mucosa after inoculation, which suggested that those plants could host this nematode in natural biomes. Nursery soil should be disinfested before seeding the native forest plants for reforestation purposes

Vanessa A., Antes; Anna P., Comerlato; Adílson Ricken, Schuelter; Regina M.D.G., Carneiro; Cleber, Furlanetto.

2012-04-01

267

Inheritance and mapping of Mj-2, a new source of root-knot nematode (Meloidogyne javanica) resistance in carrot  

Science.gov (United States)

Root-knot nematodes limit carrot production around the world by inducing taproot forking and galling deformities that render carrots unmarketable. In warmer climates, Meloidogyne javanica and M. incognita are most prevalent. In F2 and F3 progeny from the cross between an Asian carrot resistant to M....

268

Evaluation of Cover Crops with Potential for Use in Anaerobic Soil Disinfestation (ASD) for Susceptibility to Three Species of Meloidogyne  

Science.gov (United States)

Several cover crops with potential for use in tropical and subtropical regions were assessed for susceptibility to three common species of root-knot nematode, Meloidogyne arenaria, M. incognita, and M. javanica. Crops were selected based on potential use as organic amendments in anaerobic soil disin...

269

Mentha x piperita, Mentha spicata and Effects of Their Essential Oils on Meloidogyne in Soil  

OpenAIRE

Six peppermint (Mentha x piperita) and six spearmint (M. spicata) PI accessions were inoculated with Meloidogyne incognita race 3 and M. arenaria race 2, under greenhouse conditions. No galls formed on roots of any of the plants inoculated with 1,800 eggs/pot. Fewer than two galls per root system formed on three PI accessions of peppermint inoculated with M. incognita at 5,400 eggs/pot. Only one peppermint accession developed galls when inoculated with M. arenaria, whereas none of the spearmi...

Walker, J. T.; Melin, J. B.

1996-01-01

270

Effect of Carbamate, Organophosphate, and Avermectin Nematicides on Oxygen Consumption by Three Meloidogyne spp.  

OpenAIRE

Second-stage juveniles (I2) of Meloidogyne arenaria consumed more oxygen (P ? 0.05) than M. incognita J2, which in turn consumed more than M. javanica J2 (4,820, 4,530, and 3,970 ?l per hour per g nematode dryweight, respectively). Decrease in oxygen consumption depended on the nematicide used. Except for aldicarb, there was no differential sensitivity among the three nematode species. Meloidogyne javanica had a greater percentage decrease (P ? 0.05) in oxygen uptake when treated with al...

Nordmeyer, D.; Dickson, D. W.

1989-01-01

271

Infection, Reproduction Potential, and Root Galling by Root-knot Nematode Species and Concomitant Populations on Peanut and Tobacco  

OpenAIRE

Single populations of Meloidogyne arenaria races 1 (MA1) and 2 (MA2) and M. hapla (MH), and mixed populations of MA1 + MA2 and MA1 + MH with four inoculum levels of eggs were tested on peanut cv. 'Florigiant' and M. incognita-resistant tobacco cv. 'McNair 373' in a greenhouse experiment. Root infection, female development, and reproduction of MA2 on peanut and MA1 on resistant tobacco were limited at 2 and 6 weeks. MA1, MH, and MA1 + MH on peanut had similar root infection (total parasitic fo...

Hirunsalee, Anan; Barker, K. R.; Beute, M. K.

1995-01-01

272

Comparison of Brassicaceae for Meloidogyne incognita and Pratylenchus penetrans Control  

Science.gov (United States)

There is growing interest in utilizing Brassicaceae seed meals in pest management systems. To achieve consistent and reliable pest suppression with these materials, we must have a deeper understanding of their relative toxicities and the application rates necessary for acceptable control. Towards t...

273

Nematode Population Changes and Forage Yields of Six Corn and Sorghum Cultivars  

OpenAIRE

Two temperate corn (Zea mays) hybrids (Pioneer 3320 and Northrup King 508), two tropical corn cultivars (Pioneer X304C hybrid and Florida SYN-1 experimental open pollinated cultivar), the sorghum (Sorghum bicolor) x sudangrass (Sorghum sudanense) hybrid DeKalb SX-17, and the sorghum hybrid DeKalb FS25E were compared for effect on nematode densities and forage yield in three plantings (one single-crop and one double-crop system) in Florida. Final population densities of Meloidogyne incognita i...

Mcsorley, R.; Gallaher, R. N.

1991-01-01

274

Circumscribed alopecia areata incognita.  

Science.gov (United States)

The characteristic lesion of alopecia areata is a smooth bald patch on the scalp. When there is no bald surface it is called alopecia areata incognita. To date, all cases of alopecia areata reported as so-called 'incognito' have shown a diffuse involvement of the scalp as in acute telogen effluvium. Recently, we have observed two patients who showed localised hair thinning of the scalp without bald spots. Histopathologically, the lesions were typical of alopecia areata with peribulbar lymphocytic infiltrates. The response to corticosteroid treatment and its clinical course were also compatible with alopecia areata. PMID:22671761

Park, Jin; Song, Ki-Hun; Nam, Kyung-Hwa

2013-02-01

275

Influence of Six Vegetable Cultivars on Reproduction of Meloidogyne javanica  

OpenAIRE

Replicated field and greenhouse experiments were used to evaluate the effect of tomato, cabbage, cucumber, carrot, Amaranthus hybridus, and pepper on growth and fecundity of Meloidogyne spp., particularly M. javanica. In the field tests, tomato, cucumber, and carrot favored population increases of Meloidogyne spp., while Amaranthus, pepper, and cabbage limited them. Some cropping sequences that included crops from the latter group had a suppressive effect on population growth. Thus, of the 36...

Bafokuzara, N. D.

1983-01-01

276

Efecto de diferentes densidades poblacionales de Meloidogyne hapla sobre uchuva (Physalis peruviana L.) en invernadero / Effect of different population densities of Meloidogyne hapla on the cape gooseberry (Physalis peruviana L.) in greenhouse  

Scientific Electronic Library Online (English)

Full Text Available Este estudio se realizó en el Centro de Investigaciones y Asesorías Agroindustriales de la Universidad de Bogotá Jorge Tadeo Lozano, Chía (Cundinamarca), bajo condiciones de invernadero, durante diez meses de cultivo. Se evaluó el efecto de diferentes densidades poblacionales de Meloidogyne hapla (0 [...] , 50, 100, 200, 500 y 1.000 larvas J2/100 cc de suelo), sobre parámetros productivos de la uchuva: altura de las plantas, diámetro de tallo, peso fresco, peso seco y biomasa de follaje, peso fresco de raíces, índice de nodulación radicular y peso fresco de frutos. Se hizo análisis de varianza, pruebas de contrastes y prueba de Tukey (?=0,05), en un diseño completamente aleatorio, con seis tratamientos y cinco repeticiones, mediante el programa SAS v.8.0. El tratamiento de 500 larvas J2/100 cc suelo fue el que más afectó la altura de las plantas, el diámetro del tallo, la biomasa de follaje, el peso fresco de raíces y presentó el índice de nodulación radical más alto. No se encontraron diferencias significativas entre los tratamientos inoculados con M. hapla, para peso fresco, peso seco de follaje y peso fresco de frutos, ni para el número de larvas J2 en suelo y masas de huevos. Mediante la ecuación: Y = m + (1-m)Z P-T propuesta por Seinhorst (1965), se estableció un límite de tolerancia de 50 larvas J2 de M. hapla/100 cc suelo, para peso fresco de raíces y un límite de tolerancia de 450 larvas J2 de M. hapla/100 cc suelo, para biomasa de follaje. Abstract in english A trial was conducted at the Center of Investigations and Agroindustrial Accessory of the University Jorge Tadeo Lozano, Chía (Cundinamarca) under greenhouse condition during ten months of cultivation. The effect of different population densities of M. hapla (0, 50, 100, 200, 500 and 1,000 larvae J2 [...] /100 cc soil) on productive parameters of the cape gooseberry, such as plant height, stem diameter, fresh and dry weights of leaves, fresh weight of roots, root nodulation index and weight of fruits in four harvests were evaluated. A variance analysis, contrasts test and Tukey test, within a randomized design with six treatments, and five repetitions was done within SAS v.8.0 program. It was determined that a treatment 500 larvae J2/100 cc soil had the highest effect on the plant height, stem diameter, leaf biomass and fresh weight of roots, besides it showed the highest root nodulation index. There were no significant differences found among the treatments for fresh weight and dry weight of leaves and fruits weight. For J2 larvae’s number in soil and eggs mass, the differences among the treatments inoculated with M. hapla were not found. A tolerance limit of 50 larvas J2/l00 cc soil was derived from fitting the data of root fresh weight and a tolerance limit of 450 larvas J2/l00 cc soil from data of biomass using the equation Y=m+(1-m)Z P-T proposed by Seinhorst (1965).

Nancy Eunice, Niño; Germán, Arbeláez; Rafael, Navarro.

2008-04-30

277

Phylogenetic Analyses of Meloidogyne Small Subunit rDNA.  

Science.gov (United States)

Phylogenies were inferred from nearly complete small subunit (SSU) 18S rDNA sequences of 12 species of Meloidogyne and 4 outgroup taxa (Globodera pallida, Nacobbus abberans, Subanguina radicicola, and Zygotylenchus guevarai). Alignments were generated manually from a secondary structure model, and computationally using ClustalX and Treealign. Trees were constructed using distance, parsimony, and likelihood algorithms in PAUP* 4.0b4a. Obtained tree topologies were stable across algorithms and alignments, supporting 3 clades: clade I = [M. incognita (M. javanica, M. arenaria)]; clade II = M. duytsi and M. maritima in an unresolved trichotomy with (M. hapla, M. microtyla); and clade III = (M. exigua (M. graminicola, M. chitwoodi)). Monophyly of [(clade I, clade II) clade III] was given maximal bootstrap support (mbs). M. artiellia was always a sister taxon to this joint clade, while M. ichinohei was consistently placed with mbs as a basal taxon within the genus. Affinities with the outgroup taxa remain unclear, although G. pallida and S. radicicola were never placed as closest relatives of Meloidogyne. Our results show that SSU sequence data are useful in addressing deeper phylogeny within Meloidogyne, and that both M. ichinohei and M. artiellia are credible outgroups for phylogenetic analysis of speciations among the major species. PMID:19265950

De Ley, Irma Tandingan; De Ley, Paul; Vierstraete, Andy; Karssen, Gerrit; Moens, Maurice; Vanfleteren, Jacques

2002-12-01

278

Enhanced Synthesis of Antioxidant Enzymes, Defense Proteins and Leghemoglobin in Rhizobium-Free Cowpea Roots after Challenging with Meloydogine incognita  

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Full Text Available The root knot nematodes (RKN, Meloydogine spp., particularly Meloidogyne incognita and Meloidogyne javanica species, parasitize several plant species and are responsible for large annual yield losses all over the world. Only a few available chemical nematicides are still authorized for RKN control owing to environmental and health reasons. Thus, plant resistance is currently considered the method of choice for controlling RKN, and research performed on the molecular interactions between plants and nematodes to identify genes of interest is of paramount importance. The present work aimed to identify the differential accumulation of root proteins of a resistant cowpea genotype (CE-31 inoculated with M. incognita (Race 3 in comparison with mock-inoculated control, using 2D electrophoresis assay, mass spectrometry identification and gene expression analyses by RT-PCR. The results showed that at least 22 proteins were differentially represented in response to RKN challenge of cowpea roots mainly within 4–6 days after inoculation. Amongst the up-represented proteins were SOD, APX, PR-1, ?-1,3-glucanase, chitinases, cysteine protease, secondary metabolism enzymes, key enzymes involved in ethylene biosynthesis, proteins involved in MAPK pathway signaling and, surprisingly, leghemoglobin in non-rhizobium-bacterized cowpea. These findings show that an important rearrangement in the resistant cowpea root proteome occurred following challenge with M. incognita.

Jose T. A. Oliveira

2014-11-01

279

Response of Some Common Annual Bedding Plants to Three Species of Meloidogyne  

OpenAIRE

Twelve ornamental bedding plant cultivars were grown in soil infested with isolates of Meloidogyne incognita race 1, M. javanica, or M. arenaria race 1 in a series of tests in containers in a growth room. Root galling (0-5 scale) and eggs/plant were evaluated 8-10 weeks after soil infestation and seedling transplantation. Snapdragon, Antirrhinum majus cv. First Ladies, was extensively galled and highly susceptible (mean gall rating ?4.2 and ?14,500 eggs/plant), and Celosia argentea cv. Ce...

Mcsorley, R.; Frederick, J. J.

1994-01-01

280

Occurrence of the root-knot nematode Meloidogyne arenaria on balm and in a mixed population with M. javanica on grapevine in Greece  

OpenAIRE

Summary The root-knot nematode Meloidogyne arenaria was found in Greece infecting balm (Melissa officinalis L.) and grapevine (Vitis vinifera L.). The isolate from balm was M. arenaria while the one from grapevine was a mixture of M. arenaria and M. javanica (prevalent species). This is the first report of the M. arenaria species in the country in which identification was based on biochemical methods and its occurrence on balm is a new host record.

Karanastasi, E.; Conceic?a?o, I. Da; Santos, M. Dos; Tzortzakakis, E.; Abrantes, I. O.

2008-01-01

281

Morphological, molecular, and differential-host characterization of Meloidogyne floridensis n. sp (Nematoda : Meloidogynidae), a root-knot nematode parasitizing peach in Florida  

OpenAIRE

A root-knot nematode, Meloidogyne floridensis n. sp., is described and illustrated from peach originally collected from Gainesville, Florida. This new species resembles M. incognita, M. christiei, M. graminicola, and M. hispanica, but with LM and SEM observations it differs from these species either by the body length, shape of head, tail and tail terminus of second-stage juveniles, body length and shape of spicules in males, and its distinctive female perineal pattern. This pattern has a hig...

Handoo, Z. A.; Nyczepir, A. P.; Esmenjaud, D.; Beek, J. G.; Castagnone-sereno, P.; Carta, L. K.; Skantar, A. M.; Higgins, J. A.

2004-01-01

282

Morphological and Molecular Characterization of a New Root-Knot Nematode, Meloidogyne thailandica n. sp. (Nematoda: Meloidogynidae), Parasitizing Ginger (Zingiber sp.)  

OpenAIRE

A root-knot nematode Meloidogyne thailandica n. sp. was discovered on roots of ginger (Zingiber spp.) intercepted from Thailand in October 2002 by the U.S. Department of Agriculture Animal and Plant Health Inspection Service at the port of San Francisco. Comparison by light microscopy (LM) and scanning electron microscopy (SEM) to five other morphologically related species (M. incognita, M. arenaria, M. microcephala, M. megatyla, and M. enterolobii) revealed that the new species differs from ...

Handoo, Z. A.; Skantar, A. M.; Carta, L. K.; Erbe, E. F.

2005-01-01

283

Morphological, Molecular, and Differential-Host Characterization of Meloidogyne floridensis n. sp. (Nematoda: Meloidogynidae), a Root-Knot Nematode Parasitizing Peach in Florida  

OpenAIRE

A root-knot nematode, Meloidogyne floridensis n. sp., is described and illustrated from peach originally collected from Gainesville, Florida. This new species resembles M. incognita, M. christiei, M. graminicola, and M. hispanica, but with LM and SEM observations it differs from these species either by the body length, shape of head, tail and tail terminus of second-stage juveniles, body length and shape of spicules in males, and its distinctive female perineal pattern. This pattern has a hig...

Handoo, Z. A.; Nyczepir, A. P.; Esmenjaud, D.; Beek, J. G.; Castagnone-sereno, P.; Carta, L. K.; Skantar, A. M.; Higgins, J. A.

2004-01-01

284

Resistência de porta-enxertos para pessegueiro e ameixeira aos nematóides causadores de galhas (Meloidogyne spp. Resistance of rootstock for peach tree and plum to root-knot nematodes (Meloidogyne spp.  

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Full Text Available O trabalho foi realizado com o objetivo de comparar o comportamento de cinco diferentes porta-enxertos para frutas de caroço em frente a duas espécies de nematóides do gênero Meloidogyne (Meloidogyne javanica e Meloidogyne incognita. O cultivar GF 677 foi obtido a partir do cultivo in vitro e os demais porta-enxertos a partir de sementes. Aos dois meses, as plântulas foram repicadas e inoculadas com uma mistura de Meloidogyne javanica e M. incognita aos 30, 60 e 70 dias após o plantio em canteiros incorporando-se 0,2kg de solo altamente infestado com os nematóides ao redor de cada planta. Ao final do experimento, avaliaram-se o desenvolvimento das plantas e o grau de infecção de cada cultivar. O grau de resistência dos cultivares foi estimado a partir do índice de galhas, obtido através de uma escala de grau ou nota, a qual varia de 0 a 5, em função do número de galhas ou ootecas. Os resultados obtidos demonstraram que o cultivar Okinawa não apresentou galhas no sistema radicular e na análise de crescimento foi superior aos demais cultivares. Os cultivares R-15-2 e Aldrighi foram considerados resistentes aos fitonematóides por apresentarem pequeno número de galhas no sistema radicular. Já o cultivar GF 677 apresentou maior número de galhas no sistema radicular, chegando a 126 galhas/g de raiz.The work was carried out with the objective of comparing the response of five different stone fruit rootstocks to two nematode species (Meloidogyne javanica and Meloidogyne incognita. The cultivar GF677, which was obtained from in vitro cultivation and the others rootstocks, were obtained from seedlings. Two month old plants were transplanted and inoculated with a mixture of both nematode species at 30, 60, 70 days after planting, by incorporating 0.2kg of highly infested soil around each cultivar. The development of the roststocks were evaluated at the end of the experiment. Number of galls, ranging from 0 to 5 was used to score the level of resistance of each cultivar. The results showed that cultivar Okinawa did not present any root galls and also had a superior growth than the other cultivars. The cultivars R-15-2 and Aldrighi presented small numbers of galls in the roots, they were considered resistant to nematodes. On the other hand, the cultivar GF677 presented the largest number of galls in the roots, achieving 126 galls/g of root.

José Carlos Fachinello

2000-03-01

285

Susceptibilidad de genotipos de Solanum spp. al nematodo causante del nudo radical Meloidogyne spp. (chitwood  

Directory of Open Access Journals (Sweden)

Full Text Available

El cultivo del lulo (Solanum quitoense L. presenta una disminución en su productividad, debido al ataque de patógenos como el nematodo del nudo radical Meloidogyne  spp., en el Departamento  de Nariño (Colombia, se han reportado incidencias cercanas al 79%, y pérdidas del 50%.   En la presente investigación, se colectaron 45 genotipos de (Solanum quitoense  L. en los Departamentos  de Nariño  y Putumayo  y 4 genotipos  silvestres  (S. mammosum, S. hirtum,       S. marginatum  y S. umbellatum buscando fuentes de resistencia al nematodo. Se inocularon 9 plantas de cada genotipo de dos meses de edad con 10000 huevos de Meloidogyne spp., dejando tres testigos por cada material. Las variables evaluadas fueron: altura de planta, severidad, incidencia, peso fresco (tallo y raíz y especies prevalentes de Meloidogyne spp. Se hizo una clasificación de genotipos mediante escala de resistencia y regresión entre la severidad y las demás variables para establecer el efecto de Meloidogyne spp. sobre los genotipos de planta. Los resultados mostraron 100% de incidencia del nematodo en  todos  los  genotipos,  2.04%  genotipos  resistentes,  34.7%  moderadamente  resistentes, 42.8% moderadamente susceptibles, 18.3% susceptibles, y 2.04% altamente susceptibles. El genotipo SQbr05 resistente, no se vio afectado por la severidad, al contrario SQbc04 genotipo susceptible, mostró reducciones significativas en peso fresco de tallo y raIz, (R2 = 0.71 y 0.98,el genotipo silvestre (S. mammosum es altamente susceptible, Meloidogyne incognita presentó 55.31% de presencia. El genotipo SQbr05 es promisorio para ser evaluado en campo.

Gelpud Chaves Cristian

2011-03-01

286

Glomus intraradices para el control de Meloidogyne incognita (Kofoid & White) Chitwood en condiciones protegidas / Glomus intraradices for the Control of Meloidogyne incognita (Kofoid & White) Chitwood under Protected Conditions  

Scientific Electronic Library Online (English)

Full Text Available Se evaluó el efecto de la aplicación del hongo micorrízico arbuscular Glomus intraradices en plantas de tomate (Lycopersicon esculentum Mill.) cv. Maya. Las variables de reproducción del nematodo estimadas fueron número de agallas por planta_1 (NA), número de hembras por g_1de raíz teñida (NHE) y nú [...] mero de huevos por g_1 de raíz licuada (NHU). Para las plantas, las variables agronómicas de vigor consideradas correspondieron a altura de planta (AP), peso de fruto (PF), peso de raíz (PR), volumen radical (VR) y peso seco de planta (PS). Los análisis de varianza realizados con las variables NA, NHE, AP, PF, PR, VR y PS no mostraron diferencias significativas entre tratamientos. Solo se detectó diferencias entre tratamientos con la variable NHU; sin embargo, el NA fue mayor en el tratamiento testigo sin la inoculación de la micorriza arbuscular Glomus intraradices, con un promedio de 467 agallas por planta. Se observó que conforme se incrementaron las dosis de inóculo del hongo micorrízico, disminuyó la formación de agallas en las plantas. Se obtuvo una diferencia de al menos el 39% menos de formación de agallas en los tratamientos inoculados con el hongo micorrízico. Abstract in english The effects of the inoculation with arbuscular micorrhizal fungus Glomus intraradices on tomato (Lycopersicon esculentum Mill.) cv. Maya were evaluated. Variables related to nematode reproduction such as number of galls per plant_1 (NA), number of females per g-1 of stained root (NF) and number of e [...] ggs per g_1 of blended root (NE) were estimated. Plant agronomic variables such as plant height (AH), fruit weight (FW), root weight (RW), root volume (RV) and plant dry weight (DW) were also evaluated. The variance analysis for the variables NA, NF, AH, FW, RW, RV and DW did not show significant differences among treatments. Significant difference was only observed on the variable NE. The variable NA was higher on the control plants with no inoculation of arbuscular micorrhizal Glomus intraradices with an average of 467 root-knots per plant; it was also observed that the plants treated with higher concentration of the inoculum showed lower number of root-knots per plant. In general, it was observed at least 39% lower knot-root formation on plants inoculated with the micorrhizal fungus.

Jairo, Cristóbal Alejo; Elizabeth, Herrera-Parra; Vicente, Reyes Oregel; Esaú, Ruiz Sánchez; José María, Tun Suárez; Teresita, Celis Rodríguez.

2010-03-01

287

Additive Effects of Meloidogyne arenaria and Sclerotinin rolfsii on Peanut  

OpenAIRE

Field observations have suggested that infection of peanut by Meloidogyne arenaria increases the incidence of southern blight caused by Sclerotium rolfsii. Three factorial experiments in microplots were conducted to determine if interactions between M. arenaria and S. rolfsii influenced final nematode population densities, incidence of southern blight, or pod yield. Treatments included four or five initial population densities of M. arenaria and three inoculum rates of S. rolfsii. Final nemat...

Starr, J. L.; Shim, M. -y; Lee, T. A.; Simpson, C. E.

1996-01-01

288

Effect of Winter Cover Crops on Nematode Population Levels in North Florida  

Science.gov (United States)

Two experiments were conducted in north-central Florida to examine the effects of various winter cover crops on plant-parasitic nematode populations through time. In the first experiment, six winter cover crops were rotated with summer corn (Zea mays), arranged in a randomized complete block design. The cover crops evaluated were wheat (Triticum aestivum), rye (Secale cereale), oat (Avena sativa), lupine (Lupinus angustifolius), hairy vetch (Vicia villosa), and crimson clover (Trifolium incarnatum). At the end of the corn crop in year 1, population densities of Meloidogyne incognita were lowest on corn following rye or oat (P ? 0.05), but no treatment differences were observed in year 2. Wheat was a good host to Paratrichodorus minor, whereas vetch was a poor host, but numbers of P. minor were not lower in vetch-planted plots after corn was grown. The second experiment used a split-plot design in which rye or lupine was planted into field plots with histories of five tropical cover crops: soybean (Glycine max), cowpea (Vigna unguiculata), sorghum-sudangrass (Sorghum bicolor × S. sudanense), sunn hemp (Crotalaria juncea), and corn. Population densities of M. incognita and Helicotylenchus dihystera were affected by previous tropical cover crops (P ? 0.05) but not by the winter cover crops present at the time of sampling. Plots planted to sunn hemp in the fall maintained the lowest M. incognita and H. dihystera numbers. Results suggest that winter cover crops tested did not suppress plant-parasitic nematodes effectively. Planting tropical cover crops such as sunn hemp after corn in a triple-cropping system with winter cover crops may provide more versatile nematode management strategies in northern Florida. PMID:19262833

Wang, K.-H.; McSorley, R.; Gallaher, R. N.

2004-01-01

289

Efeito da Incorporação de Folhas de Nim ao Solo sobre o Complexo Fusarium x Meloidogyne em Quiabeiro Effect of amendment of soil with neem leaf on Fusarium x Meloidogyne on okra  

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Full Text Available O objetivo deste trabalho foi avaliar o efeito da incorporação de folhas frescas de nim (Azadirachta indica ao solo, sobre o complexo Fusarium x Meloidogyne em quiabeiro (Abelmoschus esculentum em um experimento realizado em condições de casa de vegetação. Os tratamentos constaram da adição de 25g ou 50g de folhas trituradas/kg de solo previamente autoclavado e inoculado com M. incognita, Fusarium oxysporum f. sp. vasinfectum, juntos e isoladamente, contidos em vasos com capacidade de 2 L. Solo sem folhas de nim serviu como testemunha. O experimento foi realizado seguindo um delineamento inteiramente casualizado com seis repetições, sendo cada repetição representada por um vaso com 5 plantas. As folhas foram incorporadas 30 dias antes do plantio e a avaliação deu-se 90 dias após o plantio, adotando-se a percentagem de plantas mortas como parâmetro para avaliar o efeito dos tratamentos. A incorporação de 50g de folhas frescas de nim foi eficiente para o controle de Meloidogyne e Fusarium isoladamente, bem como na interação desses patógenos. A incorporação de 25g de folhas de nim mostrou-se eficiente apenas para o controle de Meloidogyne isoladamente.The objective of this study was to investigate the effect of soil ammendment with neem (Azadirachta indica leaf on the complex Fusarium x Meloidogyne in okra (Abelmoschus esculentum in greenhouse conditions. The treatments consisted of the addition of 25g or 50g of leaves per kg of soil and infested with M. incognita and Fusarium oxysporum f. sp. vasinfectum, together and separately, contained in pots with capacity of 2 L. Soil without supplement it served as the control. The experimental design was completely randomized with six replications and five plants per pot. The leaves were incorporate 30 days before planting and the evaluation 90 days later. The percentagem of dead plants was used to evaluate the efficiency of neem. The incorporation of 50g of fresh neem leaves was efficient in the control of both Meloidogyne and Fusarium separately as well as in their interaction. The incorporation of 25g of neem leaves was shown efficient just for the control of Meloidogyne separately.

Gilson Soares da Silva

2008-12-01

290

Evaluation of soil biodesinfestation with crop and garden residues in the control of root-knot nematodes populations.  

Science.gov (United States)

Fresh crop and garden residues were applied both under laboratory conditions and in commercial greenhouse in order to asses their effect on soil nematodes populations and soil fertility. In the laboratory experiments, dosages of 5 to 20 g of cabbage residues, chicken manure, cabbage residues+chicken manure, grass+chicken manure, as well as leaves and stems of orange tree, pine tree, oleander, olive tree, palm tree and boxwood were mixed with 500 g soil having root-knot nematodes (Meloidogyne incognita) and soil moisture was adjusted at field capacity. A control treatment without residues was also included. The mixtures were kept into plastic bags, with four replications, and the bags were incubated for four weeks at 30 degrees C, when nematological and soil fertility analyses were carried out. In general, all these materials significantly (P < 0.05) reduced M. incognita populations and increased saprophagous nematodes, with slight effects on soil fertility except for the K increase with residues application. Tomato plants susceptible to M. incognita were planted in pots with 300 cm3 of the treated soils and kept for five weeks in a growth chamber (24 +/- 1 degrees C, 14 hours light), when root galling indices were evaluated. Most materials applied reduced root galling indices as regards to the control. In the greenhouse experiment, cabbage residues, cabbage residues+chicken manure, grass+chicken manure and grass+cabbage residues were applied to the soil and covered with a polyethylene sheet for 5 weeks. A cabbage residues:chicken manure treatment and a control (not-amended) treatment, without polyethylene, were also included. At the end of the experiment, the nematological analysis showed that all materials successfully controlled M. incognita populations, reaching 86-100% mortality with organic amendments vs. 6% for the control. After the greenhouse biodesinfestation experiment, a tomato crop was grown for one month, when root galling indices were determined. All materials significantly reduced this value from 4.75 in the control to 1.0-2.25 with the organic amendments, except for the cabbage residues+chicken manure treatment without polyethylene (index = 4.0). Our results show that fresh crop and garden residues successfully reduced M. incognita populations and root galling indices when applied with polyethylene covers, having good potential to be considered in integrated management programs. PMID:18399508

López-Cepero, J; Piedra Buena, A; Díez-Rojo, M A; Regalado, R; Brito, E; Hernández, Z; Figueredo, M; Almendros, G; Bello, A

2007-01-01

291

Susceptibilidad de genotipos de Solanum spp. al nematodo causante del nudo radical Meloidogyne spp. (chitwood) / Susceptibility of genotypes of Solanum spp. to the nematode causative of the root knot Meloidogyne spp. (chitwood)  

Scientific Electronic Library Online (English)

Full Text Available SciELO Colombia | Language: Spanish Abstract in spanish El cultivo del lulo (Solanum quitoense L.) presenta una disminución en su productividad, debido al ataque de patógenos como el nematodo del nudo radical Meloidogyne spp., en el Departamento de Nariño (Colombia), se han reportado incidencias cercanas al 79%, y pérdidas del 50%. En la presente investi [...] gación, se colectaron 45 genotipos de (Solanum quitoense L.) en los Departamentos de Nariño y Putumayo y 4 genotipos silvestres (S. mammosum, S. hirtum, S. marginatum y S. umbellatum) buscando fuentes de resistencia al nematodo. Se inocularon 9 plantas de cada genotipo de dos meses de edad con 10000 huevos de Meloidogyne spp., dejando tres testigos por cada material. Las variables evaluadas fueron: altura de planta, severidad, incidencia, peso fresco (tallo y raíz) y especies prevalentes de Meloidogyne spp. Se hizo una clasificación de genotipos mediante escala de resistencia y regresión entre la severidad y las demás variables para establecer el efecto de Meloidogyne spp. sobre los genotipos de planta. Los resultados mostraron 100% de incidencia del nematodo en todos los genotipos, 2.04% genotipos resistentes, 34.7% moderadamente resistentes, 42.8% moderadamente susceptibles, 18.3% susceptibles, y 2.04% altamente susceptibles. El genotipo SQbr05 resistente, no se vio afectado por la severidad, al contrario SQbc04 genotipo susceptible, mostró reducciones significativas en peso fresco de tallo y raíz, (R² = 0.71 y 0.98), el genotipo silvestre (S. mammosum) es altamente susceptible, Meloidogyne incognita presentó 55.31% de presencia. El genotipo SQbr05 es promisorio para ser evaluado en campo. Abstract in english The green orange (Solanum quitoense L.) crop has decreased in its productivity due to the pathogens attack such as the root knot nematode Meloidogyne spp. In the Nariño Department of Colombia, pest incidences near to 79% and losses of 50% have been reported. In this study, 45 genotypes of Solanum qu [...] itoense were collected in Nariño and Putumayo Departments. Four wild genotypes (S. mammosum, S. hirtum, S. marginatum and S. umbellatum) were collected to look for nematode resistance sources. Nine plants of each genotype two month old were inoculated with 10000 eggs of Meloidogyne spp., leaving three plants as control by each material. The evaluated variables were: plant height, pest severity, pest incidence, fresh weight (stem and root) and Meloidogyne spp. prevalent species. A genotype classification was made through a pest resistance scale and regression among severity and the rest of variables to determine the effect of Meloidogyne spp. over the plant genotypes. The results showed 100% nematode incidence in all genotypes, resistant genotypes ².04%, 34.7% moderately resistant, 42.8% moderately susceptible, 18.3% were susceptible, and 2.04% highly susceptible. The SQbr05 resistant genotype, was not affected by severity. On the other hand, the pest susceptible genotype SQbc04 showed significant reductions in stem and root fresh weight (R² = 0.71 and 0.98), the wild genotype (S. mammosum) was highly susceptible, Meloidogyne incognita showed 55.31% of presence. The SQbr05 genotype is promising to be evaluated in field.

Cristian, Gelpud Chaves; Edwin, Mora Marcillo; Claudia, Salazar Gonzalez.

2011-01-01

292

Susceptibilidad de genotipos de Solanum spp. al nematodo causante del nudo radical Meloidogyne spp. (chitwood) Susceptibility of genotypes of Solanum spp. to the nematode causative of the root knot Meloidogyne spp. (chitwood)  

Directory of Open Access Journals (Sweden)

Full Text Available El cultivo del lulo (Solanum quitoense L.) presenta una disminución en su productividad, debido al ataque de patógenos como el nematodo del nudo radical Meloidogyne spp., en el Departamento de Nariño (Colombia), se han reportado incidencias cercanas al 79%, y pérdidas del 50%. En la presente investigación, se colectaron 45 genotipos de (Solanum quitoense L.) en los Departamentos de Nariño y Putumayo y 4 genotipos silvestres (S. mammosum, S. hirtum, S. marginatum y S. umbellatum) buscando fuentes de resistencia al nematodo. Se inocularon 9 plantas de cada genotipo de dos meses de edad con 10000 huevos de Meloidogyne spp., dejando tres testigos por cada material. Las variables evaluadas fueron: altura de planta, severidad, incidencia, peso fresco (tallo y raíz) y especies prevalentes de Meloidogyne spp. Se hizo una clasificación de genotipos mediante escala de resistencia y regresión entre la severidad y las demás variables para establecer el efecto de Meloidogyne spp. sobre los genotipos de planta. Los resultados mostraron 100% de incidencia del nematodo en todos los genotipos, 2.04% genotipos resistentes, 34.7% moderadamente resistentes, 42.8% moderadamente susceptibles, 18.3% susceptibles, y 2.04% altamente susceptibles. El genotipo SQbr05 resistente, no se vio afectado por la severidad, al contrario SQbc04 genotipo susceptible, mostró reducciones significativas en peso fresco de tallo y raíz, (R² = 0.71 y 0.98), el genotipo silvestre (S. mammosum) es altamente susceptible, Meloidogyne incognita presentó 55.31% de presencia. El genotipo SQbr05 es promisorio para ser evaluado en campo.The green orange (Solanum quitoense L.) crop has decreased in its productivity due to the pathogens attack such as the root knot nematode Meloidogyne spp. In the Nariño Department of Colombia, pest incidences near to 79% and losses of 50% have been reported. In this study, 45 genotypes of Solanum quitoense were collected in Nariño and Putumayo Departments. Four wild genotypes (S. mammosum, S. hirtum, S. marginatum and S. umbellatum) were collected to look for nematode resistance sources. Nine plants of each genotype two month old were inoculated with 10000 eggs of Meloidogyne spp., leaving three plants as control by each material. The evaluated variables were: plant height, pest severity, pest incidence, fresh weight (stem and root) and Meloidogyne spp. prevalent species. A genotype classification was made through a pest resistance scale and regression among severity and the rest of variables to determine the effect of Meloidogyne spp. over the plant genotypes. The results showed 100% nematode incidence in all genotypes, resistant genotypes ².04%, 34.7% moderately resistant, 42.8% moderately susceptible, 18.3% were susceptible, and 2.04% highly susceptible. The SQbr05 resistant genotype, was not affected by severity. On the other hand, the pest susceptible genotype SQbc04 showed significant reductions in stem and root fresh weight (R² = 0.71 and 0.98), the wild genotype (S. mammosum) was highly susceptible, Meloidogyne incognita showed 55.31% of presence. The SQbr05 genotype is promising to be evaluated in field.

Cristian Gelpud Chaves

2011-01-01

293

Host Status of Selected Crops to Meloidogyne chitwoodi  

OpenAIRE

Various crops were tested in greenhouse and field trials for their potential utility in the rotation sequence in the potato cropping system in Meloidogyne chitwoodi-infested soils of the Klamath Basin in northeastern California and southern Oregon. Two Solarium accessions from the International Potato Center in Peru were potential sources of resistance to M. chitwoodi. Cultivars of barley, oat, rye, wheat, and white lupine were maintenance hosts, supporting the nematode population at its curr...

Ferris, H.; Carlson, H. L.; Viglierchio, D. R.; Westerdahl, B. B.; Wu, F. W.; Anderson, C. E.; Juurma, A.; Kirby, D. W.

1993-01-01

294

Interrelationships of Meloidogyne Species with Flue-cured Tobacco  

OpenAIRE

Microplot and field experiments were conducted to determine relationships of population densities of Meloidogyne spp. to performance of flue-cured tobacco. A 3-yr microplot study of these interactions involved varying initial nematode numbers (Pi).and use of ethoprop to re-establish ranges of nematode densities. Field experiments included various nematicides at different locations. Regression analyses of microplot data from a loamy sand showed that cured-leaf yield losses on 'Coker 319' for e...

Barker, K. R.; Todd, F. A.; Shane, W. W.; Nelson, L. A.

1981-01-01

295

Comparison of two sympatric Pasteuria populations isolated from a tropical vertisol soil.  

Science.gov (United States)

An isolate of Pasteuria (designated PPMJ) recovered from the root-knot nematode Meloidogyne javanica, was characterized using host preference, spore morphometrics, and serology, and compared with another sympatric Pasteuria isolate (designated PPHC) collected from the cyst nematode, Heterodera cajani. PPMJ spores were larger (x 1.5) than the PPHC spores and had a mean diameter of 3.4 ?m after fixation for electron microscopy. The central body of PPMJ spores was about twice as big as the central body of PPHC spores. The host preference tests, based on spore attachment to the nematode cuticle, revealed that Meloidogyne incognita, M. javanica, M. hapla, Pratylenchus coffeae, and Pratylenchus sp. were hosts of PPMJ but not of PPHC. It was found that males of Radopholus similis were hosts of PPHC. Western blot analysis of spore extracts probed with a polyclonal antiserum raised against PPHC spores showed an antigenic ladder which had similarities to lipopolysaccharide; another antiserum revealed differences in the molecular weight of antigens of the different spore isolates. Population diversity can therefore be vastly altered by the maintenance and culture of the bacterium on a particular host. The implications of these results are discussed in relation to the use of Pasteuria as a biological control agent. PMID:24415311

Sharma, S B; Davies, K G

1996-07-01

296

Effect of Some Plant Extracts on the Hatch of Meloidogyne incognita Eggs  

OpenAIRE

Root-knot nematodes are one of the major limiting factors affecting plant growth and yield. Currently, synthetic pesticides are principle means used to control the nematodes but natural products may provide a safer alternative. Nematicidal compounds have been identified in a wide diversity of plant species. A study was conducted to evaluate potential of aqueous extracts from Azadirachta indica, Carica papaya, Ocimum sanctum, Ricinus communis and Tagetes patula, in controlling the hatch of egg...

Anuja Bharadwaj; Satyawati Sharma

2007-01-01

297

Isolation of Nematicidal Triterpenoid Saponins from Pulsatilla koreana Root and Their Activities against Meloidogyne incognita  

OpenAIRE

Pulsatilla koreana, a species endemic to Korea, is an important herb used in traditional medicine to treat amoebic dysentery and malaria. In the present study, 23 oleanane-type triterpenoid saponins 1–23 and eight lupane-type triterpenoid saponins 24–31 were isolated from the roots of P. koreana. Their structures were elucidated on the basis of spectroscopic data. The methanol extract and isolated compounds were next assessed for nematicidal activity against the root-knot nematode (Meloid...

Byung Soo Han; Chang Sup Moon; Hyo Jeung Byun; Suk Jun Lee; Seo Young Yang; Xi Tao Yan; Ya Nan Sun; Wei Li; Young Ho Kim

2013-01-01

298

Dose response of soilborne plant pathogens and Meloidogyne incognita to citrus-based experimental compounds.  

Science.gov (United States)

Two novel citrus-based compounds have been tested in vitro against Colletotrichum gleosporioides, Fusarium oxysporum, Sclerotinia sclerotiorum, Sclerotium rolfsii, Rhizoctonia solani, Verticillium albo-atrum, Pythium aphanidermatum, P. myriotilum, Phytophthora nicotianae and P. capsici. One of the...

299

Mustard seed meal mixtures: management of Meloidogyne incognita on pepper and potential phytotoxicity  

Science.gov (United States)

Meals produced when oil is extracted from brassicaceous seeds have been shown to suppress weeds and soilborne pathogens. These seed meals are commonly used individually as soil amendments; the goal of this research was to evaluate seed meal mixes of Brassica juncea Bj and Sinapis alba (Sa) against ...

300

Management of Root-Nematode (Meloidogyne SPP)  

International Nuclear Information System (INIS)

Greenhouse and field experiments were undertaken to determine the possibility of using soil amendments with different C:N levels or applied at different rates and times in the control of root-knot nematodes (Meloidogyne spp.)in tomato c.v Cal J.A naturally infested field was used while artificial inoculation was done in the greenhouse. Root galling was rated on a scale of 0-10, nematode population was estimated by counting second stage juveniles extracted from 200 cm3 soil and fruit yields were recorded at the end of the season. Nematode population densities and galling indices were significantly (P< or=0.05) lower in amended soils compared to the control. Application of the amendments also resulted in significant (P< or=0.05) increase in yields. Chicken manure, compost manure, neem products and pig manure were were the most effective amendments. Fresh chicken manure had a more suppressive effect on nematode than when the manure was decomposed within or outside a nematode infested field. A general decrease in juvenile populations and galling was observed with increase of organic amendments applied

301

Effects of Peanut Genotypes on Meloidogyne Species Interactions  

OpenAIRE

A 3-year microplot study was conducted to characterize the interaction between Meloidogyne arenaria race 1 (MA1) and M. hapla (MH), as affected by the five peanut genotypes: Florigiant, NC 7, NC 6, NC Ac 18416, and NC Ac 18016. The interactive effects on infection (total parasitic forms per root unit) and reproduction potentials of each nematode species and crop damage were determined. As a single population, MA1 had greater infection capacity and caused more crop damage than did MH, but both...

Hirunsalee, Anan; Barker, K. R.; Beute, M. K.

1995-01-01

302

Estimation of partial resistance in potato genotypes against Meloidogyne chitwoodi  

OpenAIRE

Three new potato genotypes, designated AR 04-4107, AR 04-4096 and AR 04-4098, with resistance towards Meloidogyne chitwoodi, and the susceptible cv. Désirée were grown at a range of population densities of M. chitwoodi in a climate-controlled glasshouse in order to establish the presence and degree of partial resistance. Tuber parts of about 12 g were planted at densities (Pi) of 0, 0.5, 1, 2, 4, 8, 16, 32, 64, 128 and 256 second-stage juveniles (J2) (g dry soil)?1. The plants were allowe...

Norshie, P. M.; Been, T. H.; Schomaker, C. H.

2011-01-01

303

Peanut-Cotton Rotations for the Management of Meloidogyne arenaria  

OpenAIRE

The efficacy of 'Deltapine 90' cotton (Gossypium hirsutum) in rotation with 'Florunner' peanut (Arachis hypogaea) for the management of Meloidogyne arenaria was studied for 2 years in a field in southeastern Alabama. In 1985, M. arenaria juvenile populations in plots with cotton were 98% lower than in plots with peanut. Peanut and cotton yields were increased by treatment with aldicarb (3.3 kg a.i./ha in a 20-cm-band) in 1985 but not in 1986. In 1986, peanut yields were highest and M. arenari...

Rodri?guez-ka?bana, R.; Ivey, H.; Backman, P. A.

1987-01-01

304

Importance of Temperature in the Pathology of Meloidogyne hapla and M. chitwoodi on Legumes  

OpenAIRE

Effects of temperatures on the host-parasite relationships were studied for three legume species and four populations of root-knot nematodes from the western United States. The nematode populations were Meloidogyne hapla from California (MHCA), Utah (MHUT), and Wyoming (MHWY), and a population of M. chitwoodi from Utah (MCUT). The legumes were milkvetch (Astragalus cicer), alfalfa (Medicago sativa), and yellow sweet clover (Melilotus officinalis). All milkvetch plants survived inoculation wit...

Griffin, G. D.; Jensen, K. B.

1997-01-01

305

Competition between the Plant-parasitic Nematodes Pratylenchus neglectus and Meloidogyne chitwoodi  

OpenAIRE

In experiments on competition between Pratylenchus neglectus and Meloidogyne chitwoodi in barley, the species that parasitized the roots first inhibited penetration by the latter species. Prior presence of P. neglectus impeded the development of M. chitwoodi. Pratylenchus neglectus reduced egg production, final population levels, and reproductive index of M. chitwoodi. The reduction was linearly related to initial population densities of P. neglectus. Initial population densities of M. chitwo...

Umesh, Kodira C.; Ferris, Howard; Bayer, David E.

1994-01-01

306

Efecto del follaje de Tagetes minutasobre la nodulación radicular de Meloidogyne incognitaen Capsicum annuum, en invernadero Effect of the foliage of Tagetes minutaon Meloidogyne incognitaroot-galling on Capsicum annuumin a greenhouse  

Directory of Open Access Journals (Sweden)

Full Text Available Se investigó el efecto del follaje del “huacatay” Tagetes minutasobre la nodulación radicular producida por el nematodo Meloidogyne incognitaque parasita el “pimiento páprika” Capsicum annuumcultivado en invernadero, con la finalidad de obtener una alternativa de control de este nematodo. Se utilizaron tres grupos experimentales y un testigo, con 12 macetas cada uno, las cuales contenían suelo y arena estériles (1:1. A este substrato se adicionó el follaje de T. minutaal 20, 35 y 50% (v/v según grupo experimental, y el testigo no recibió esta enmienda. En cada maceta se sembró una plántula de C. annuum, y a la semana postsiembra se inoculó 5000 huevos de M. incognita.A las ocho semanas, se evaluaron los nódulos en sus raíces. Todas las plantas presentaron nódulos; aunque, en aquellas de los grupos experimentales el número de éstos fue menor que en las plantas testigo, con diferencia estadística significativa (p 0,05. Se concluye que el follaje de T. minutaadicionado como enmienda orgánica al 20, 35 y 50% al suelo de cultivo de plantas de C. annuum limita la nodulación radicular ocasionada por M. incognita. Lo cual sugiere su uso potencial en el control de este nematodo.The effect of the foliage of Tagetes minuta"huacatay" on Meloidogyne incognitaroot-galling on Capsicum annuum"paprika pepper" cultured in a greenhouse was researched, to obtain a control strategy for this nema-tode. Three experimental groups and one control with 12 pots each were used, which contained sterilized soil and sand (1:1. To this substrate was added cut foliage of T. minutaat 20, 35 and 50% (v/v according to the experimental group, and the control group remained without this amendment. In each pot a seedling of C. annuum was sown, and one week post-seeding was inoculated with 5000 eggs of M. incognita. Eight weeks later the root galling was evaluated. All the plants had root galling; although the number of galls in plants of the experimental groups was less than those in the control group with statistical significant difference (p 0.05. It is concluded that the foliage of T. minutaadded as organic amendment at 20, 35 and 50% to the culture soil for C. annuumplants limits the M. incognitaroot galling. That suggests its potential use in the control of this nematode.

Santos Nélida Murga-Gutiérrez

2013-06-01

307

Resistance to Meloidogyne paranaensis in wild Coffea arabica / Avaliação da resistência de cafeeiros silvestres (Coffea arabica) a Meloidogyne paranaensis  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Foram avaliados quanto à resistência a Meloidogyne paranaensis, nove acessos de cafeeiros silvestres incluindo dois cultivares bem caracterizados como testemunhas de suscetibilidade e resistência. Os experimentos foram realizados sob condições controladas em câmara de crescimento, utilizando uma pop [...] ulação clonal de M. paranaensis (fenótipo de esterase P1), proveniente do Brasil. A resistência e a suscetibilidade ao nematóide foram avaliadas com base no número total de nematóides por planta (ovos + J2) e por grama de raiz e no fator de reprodução (FR). Todos os acessos mostraram resposta à infecção por M. paranaensis similar à da testemunha resistente (FR Abstract in english Nine accessions of wild Coffea arabica from Ethiopia were evaluated for resistance to Meloidogyne paranaensis. Two well-characterized susceptible and resistant cultivars were used as comparative controls. The experiments were conducted in a growth chamber using a clonal population of M. paranaensis [...] (esterase phenotype P1) originating from Brazil. Resistance and susceptibility to the nematode were evaluated using the number of nematodes (eggs and J2) per plant, number of nematodes per gram of root and the reproduction factor (RF). All wild coffee accessions expressed a resistance response to M. paranaensis similar to that of the resistant control Nemaya (RF

Marc, Boisseau; Jamel, Aribi; Fábio Rodriguez de, Sousa; Regina M.D.G., Carneiro; François, Anthony.

2009-02-01

308

HERANÇA DA RESISTÊNCIA DE MILHO A MELOIDOGYNE JAVANICA / INHERITANCE OF RESISTANCE TO MELOIDOGYNE JAVANICA IN MAIZE  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Duas linhagens de milho, resistente (IAC Ip 365-4-1) e suscetível (IAC Ip 48-5-3) a Meloidogyne javanica, suas gerações F1, F2 e retrocruzamentos, bem como os cruzamentos recíprocos, foram avaliados em dois ensaios em casa de vegetação, em 1989/90 e 1992, em Campinas, para estudar a herança da resis [...] tência a M. javanica. Utilizou-se o delineamento inteiramente casualizado com número de repetição maior nas gerações segregantes, parcelas de uma planta por vaso plástico com 500 cm3 de areia fina, previamente tratada com brometo de metila e adubada com NPK. Cinco dias após a germinação das sementes, cada vaso foi inoculado com 5.000 ovos e larvas de M. javanica. Aos 70 e aos 60 dias após a inoculação, respectivamente, nos experimentos 1 e 2, avaliaram-se o índice de massa de ovos, o número de ovos por grama de raiz e o fator de reprodução. Não foram observadas diferenças entre os cruzamentos recíprocos. O comportamento da média do F1, a distribuição de freqüência da população F2 e a segregação monofatorial indicaram que a resistência a M. javanica da linhagem IAC Ip 365-4-1 se deve a um gene dominante associado a um pequeno efeito de polígenes. Abstract in english In order to study the inheritance of resistance to Meloidogyne javanica in corn (Zea mays), two inbred lines, IAC Ip 365-4-1 (resistant) and IAC Ip 48-5-3 (susceptible), F1, F2 and backcrosses, as well as reciprocal crosses were evaluated in two greenhouse trials, carried out at Campinas, State of S [...] ão Paulo, Brazil, in 1989/90 and 1992. Completely randomized design was utilized with more replications on segregating generations. The plot was one plant per plastic pot with 500 cm3 of fine sand treated with methyl bromide and fertilized with NPK. Five days after seed germination, each plot was inoculated with 5,000 eggs and larvae of M. javanica. Egg mass index, number of eggs per gram of fresh roots and reproduction factor were evaluated 70 and 60 days after inoculation, respectively in the first and second experiment. Reciprocal crosses showed no significant differences. F1 average, frequency distribution of F2 population and monofactorial segregation indicated that resistance of IAC Ip 365-4-1 to M. javanica was due to one major dominant gene and a minor polygenic effect.

EDUARDO, SAWAZAKI; ANA INES LUCENA, LORDELLO; RUBENS RODOLFO ALBUQUERQUE, LORDELLO.

309

Transcriptional analysis through RNA sequencing of giant cells induced by Meloidogyne graminicola in rice roots  

OpenAIRE

One of the reasons for the progressive yield decline observed in aerobic rice production is the rapid build-up of populations of the rice root knot nematode Meloidogyne graminicola. These nematodes induce specialized feeding cells inside root tissue, called giant cells. By injecting effectors in and sipping metabolites out of these cells, they reprogramme normal cell development and deprive the plant of its nutrients. In this research we have studied the transcriptome of giant cells in rice, ...

Ji, Hongli; Gheysen, Godelieve; Denil, Simon; Lindsey, Keith; Topping, Jennifer F.; Nahar, Kamrun; Haegeman, Annelies; Vos, Winnok H.; Trooskens, Geert; Criekinge, Wim; Meyer, Tim; Kyndt, Tina

2013-01-01

310

Influence of Temperature and Host Plant on the Interaction Between Pratylenchus neglectus and Meloidogyne chitwoodi  

OpenAIRE

The interaction between Pratylenchus neglectus (Pn) and Meloidogyne chitwoodi (Mc) was investigated at soil temperatures of 15, 20, and 25 C on barley and potato. Maximum numbers of Pn and Mc penetrated barley roots at 20 C, whereas a minimum number penetrated at 15 C. Pratylenchus neglectus restricted root penetration by Mc over time and vice-versa. Population densities of each species increased with increasing temperature. Concomitant inoculation of the two species resulted in lower numbers...

Umesh, Kodira C.; Ferris, Howard

1994-01-01

311

EFFECT OF SOLE AND COMBINED INOCULATION OF RALSTONIA SOLANACEARUM AND MELOIDOGYNE JAVANICA ON TOMATO  

OpenAIRE

The effects of Meloidogyne javanica alone and in different combination with Ralstonia solanacearum on tomato were investigated. The highest shoot length reduction (32.1%) was at the highest density of both the parasites over control. The highest initial population density of M. javanica was solely responsible for the highest root length reduction (33.25%) and shoot dry weight reduction (67.44%). The highest density of R. solanacearum is solely responsible for root fresh weight red...

Ghosh, P. P.; Dutta, S.

2014-01-01

312

Host Status of Selected Crops to Meloidogyne chitwoodi.  

Science.gov (United States)

Various crops were tested in greenhouse and field trials for their potential utility in the rotation sequence in the potato cropping system in Meloidogyne chitwoodi-infested soils of the Klamath Basin in northeastern California and southern Oregon. Two Solarium accessions from the International Potato Center in Peru were potential sources of resistance to M. chitwoodi. Cultivars of barley, oat, rye, wheat, and white lupine were maintenance hosts, supporting the nematode population at its current level without substantial increase or decline. Poor to nonhosts to race 1 of the nematode included cultivars of alfalfa, amaranth, oilseed radish, oilseed rape, and safflower. These crops have potential for inclusion in the cropping system but are subject to various constraints, including frost sensitivity and availability of markets. Sugarbeet, a new crop in the area, is a maintenance or better host of M. chitwoodi. Potato, tomato, and sunflower are excellent hosts. PMID:19279852

Ferris, H; Carlson, H L; Viglierchio, D R; Westerdahl, B B; Wu, F W; Anderson, C E; Juurma, A; Kirby, D W

1993-12-01

313

IDENTIFICACIÓN DE GENES CANDIDATOS DE PATOGENICIDAD EN LA INTERACCIÓN DE LA CEPA CENICAFE 9501 CON EL NEMÁTODO DEL NUDO RADICAL Meloidogyne spp. IDENTIFICATION OF PATHOGENIC CANDIDATES GENES IN THE INTERACTION OF THE CENICAFE 9501 STRAIN WITH THE ROOT KNOT NEMATODE Meloidogyne spp.  

Directory of Open Access Journals (Sweden)

Full Text Available En 1997 se registró por primera vez el aislamiento de un hongo Hyphomycete de suelos de Chinchiná (Caldas, Colombia atacando huevos y otros estadios biológicos de las especies de nematodos fitoparásitos Meloidogyne incognita y M. javanica provenientes de lotes comerciales con café. Debido a la imposibilidad de clasificarlo taxonómicamente en los géneros actuales, este aislamiento se ha denominado temporalmente como CENICAFE 9501. Dado su potencial como biocontrolador, se propuso identificar genes candidatos involucrados en el proceso de patogenicidad de huevos de Meloidogyne. Con este fin se construyeron librerías diferenciales mediante el método de hibridación sustractiva. La secuenciación de 188 clones obtenidos permitió identificar 80 unigenes, de los cuales el mayor porcentaje correspondió a secuencias sin homología (32%, seguidas por genes candidatos a funciones de patogénesis (22%, transporte celular (17%, síntesis de proteínas (11% y en menor proporción aquellos involucrados con transcripción y metabolismo primario (18%. Dentro de aquellos genes que contienen marcos de lectura con homología a proteínas que intervienen en la patogenicidad se encuentran una peptidasa, un receptor para sitios de ubiquitinación, una deubiquinasa, una ubiquinona oxidoreductasa, proteína relacionada con la degradación de pared celular, glicosil hidrolasa e hidroxilasa de ácidos grasos, asi como una serin proteasa. Se hace necesaria la validación de las funciones putativas de estos genes candidatos con el fin de incrementar el conocimiento básico de la fisiología de este hongo con potencial biorregulador.In 1997 it was reported for the first time from soil isolation of a Hyphomycete fungus from Chinchiná ( Caldas, Colombia , attacking eggs and other biological stages of the plant parasite nematodes Meloidogyne incognita and M. javanica, from commercial coffee plots. Due to the impossibility to classify it taxonomically under current genera, this isolate has been labeled in the mean time as CENICAFE 9501. Given its potential as biological control agent, the identification of canditate genes involved in pathogenicity processes on Meloidogyne eggs was proposed. With this purpose, differential libraries were constructed using the subtractive hybridization method. Sequencing of 188 clones allowed the identification of 80 unigenes, with the highest percentage corresponding to sequences without homology (32%, followed by candidate genes for pathogenesis (22%, cellular transport (17%, protein synthesis (11% and in lesser degree those involved with transcription and primary metabolism (18%. Among those genes with reading frames showing homology to proteins involved in pathogenicity can be found a peptidase, a ubiquitination receptor, a deubiquitinase, a ubiquinone oxydoreductase, a protein related to the degradation of the cell wall, a glycosyl hydrolase and fatty acid hydrolase, as well as a serine protease. A validation of the putative function of these genes is neccesary in order to increase the basic knowledge of the physiology of this fungus with bioregulation potential.

Nadya Lorena Cardona Bustos

2008-12-01

314

Morphological and Molecular Characterization of a New Root-Knot Nematode, Meloidogyne thailandica n. sp. (Nematoda: Meloidogynidae), Parasitizing Ginger (Zingiber sp.).  

Science.gov (United States)

A root-knot nematode Meloidogyne thailandica n. sp. was discovered on roots of ginger (Zingiber spp.) intercepted from Thailand in October 2002 by the U.S. Department of Agriculture Animal and Plant Health Inspection Service at the port of San Francisco. Comparison by light microscopy (LM) and scanning electron microscopy (SEM) to five other morphologically related species (M. incognita, M. arenaria, M. microcephala, M. megatyla, and M. enterolobii) revealed that the new species differs from these by one or more of the following: body, tail and hyaline tail length, shape of head, tail and tail terminus of second-stage juveniles; stylet length and shape of spicules in males; perineal pattern, stylet length and shape of knobs in females. The distinctive perineal pattern is oval to rectangular, with smooth to moderately wavy and coarse striae, and with characteristic radial structures present underneath the pattern area; the dorsal arch is high, sometimes round to rectangular, and striae in and around the anal area form a thick network-like pattern interrupted by lateral lines and large phasmids. Second-stage juveniles have a long, slender tail and long, gradually tapering hyaline tail region ending in a rounded terminus. Male spicules commonly have an acutely angled shaft with a bidentate terminus. Molecular data from the ribosomal large subunit D3 expansion segment revealed four haplotypes, two of which were unique and distinguish M. thailandica n. sp. from M. arenaria, M. incognita, and M. javanica. PMID:19262883

Handoo, Z A; Skantar, A M; Carta, L K; Erbe, E F

2005-09-01

315

Morphological, Molecular, and Differential-Host Characterization of Meloidogyne floridensis n. sp. (Nematoda: Meloidogynidae), a Root-Knot Nematode Parasitizing Peach in Florida.  

Science.gov (United States)

A root-knot nematode, Meloidogyne floridensis n. sp., is described and illustrated from peach originally collected from Gainesville, Florida. This new species resembles M. incognita, M. christiei, M. graminicola, and M. hispanica, but with LM and SEM observations it differs from these species either by the body length, shape of head, tail and tail terminus of second-stage juveniles, body length and shape of spicules in males, and its distinctive female perineal pattern. This pattern has a high to narrowly rounded arch with coarsely broken and network-like striae in and around anal area, faint lateral lines interrupting transverse striae, a sunken vulva and anus, and large distinct phasmids. Molecular data from ribosomal IGS illustrate that M. floridensis n. sp. is different from the mitotic species M. arenaria, M. incognita, and M. javanica. Data from RAPDs confirm it and suggest that this new species lies in an intermediate phylogenetic position between the previous species and the meiotic species M. hapla, M. fallax, and M. chitwoodi. Differential host tests based on annual crops and on Prunus accessions are reported. PMID:19262784

Handoo, Z A; Nyczepir, A P; Esmenjaud, D; van der Beek, J G; Castagnone-Sereno, P; Carta, L K; Skantar, A M; Higgins, J A

2004-03-01

316

Efecto de las micorrizas arbusculares y Meloidogyne spp. en tomate (Solanum lycopersicum L.) / Effect of arbuscular mycorrhizas and Meloidogyne spp. on tomato (Solanum lycopersicum L.)  

Scientific Electronic Library Online (English)

Full Text Available El estudio se desarrolló en la Universidad de Granma (Cuba) en el período comprendido de octubre/2007 a enero/2008, para determinar los efectos de las micorrizas arbusculares y Meloidogyne spp., en el cultivo del tomate (Solanum lycopersicum L.) cv. Vyta. Se utilizaron siete tratamientos, consistent [...] es en aplicaciones simples y combinadas de un concentrado de cepas nativas y no nativas de micorrizas (Glomus mosseae (Gerdemann y Trappe) y Glomus sp. (Schenck y Smith), incluyendo un testigo y dos niveles poblacionales de Meloidogyne spp., con 30 repeticiones, los cuales se establecieron sobre un diseño completamente aleatorizado en condiciones semi-controladas, con arreglo factorial. Se utilizaron macetas de 2 kg de capacidad, que contenían un sustrato estéril, compuesto por una mezcla de suelo y estiércol ovino en proporción 3:1 v:v y una población de Meloidogyne spp. procedente de Granma. Se evaluaron las variables: índice de agallamiento e indicadores del crecimiento de las plantas: altura promedio (cm), masa seca promedio (g) y el rendimiento (kg.planta-1) a los 60 días después de la inoculación del nematodo. Los datos fueron procesados mediante un análisis de varianza y comparación de medias por la prueba del rango múltiple de Duncan (p Abstract in english This study was carried out at the University of Granma (Cuba) from October 2007 to January 2008 in order to determine the effect of arbuscular mycorrhizas and Meloidogyne spp. on tomato (Solanum lycopersicum L.), var. Vyta. Seven treatments of single or combined applications of native and non-native [...] strains(Glomus mosseae (Gerdemann and Trappe), and Glomus sp. (Schenck and Smith), of arbuscular mycorrhizas and an uninoculated control) and two levels of Meloidogine spp. were included in a completely randomized design set up in a factorial arrangement with thirty replicates under semi-controlled conditions. Two kg plastic pots containing a sterile substrate with a mixture of soil and ovine manure in a 3:1 v:v. ratio, as well as a population of Meloidogyne spp. from Granma were used. The gall index and plant growth parameters such as average height (cm), average dry weight (g) and crop yield (kg.plant-1) were evaluated 60 days after nematode inoculation. The data were analyzed by an analysis of variance and the means compared by Duncan's multiple range test (p

Alejandro, Alarcón; Tony, Boicet; María, Godefoy; Macario, Bacilio-Jiménez; Wilson, Ceiro; Yurdanys, Bazán.

2013-12-01

317

Ovicidal activity of lactic acid produced by Lysobacter capsici YS1215 on eggs of root-knot nematode, Meloidogyne incognita.  

Science.gov (United States)

Lysobacter capsici YS1215 isolated from soil previously showed nematicidal potential for biological control of the root-knot nematode. In this study, lactic acid, a nematicidal compound, was isolated from culture filtrate of YS1215, and its ovicidal activity was investigated. Purification and identification of lactic acid were performed by a series of column chromatographies and identified by (1)H and (13)C NMR spectra and GC-MS analysis. Our results showed that bacterial culture filtrate containing lactic acid significantly inhibited egg hatching. The lowest egg hatch rate (5.9%) was found at a high concentration (25 ?l/ml) of lactic acid at 5 days after incubation, followed by 20 (15.2%), 15 (23.7%), 10 (29.8%), and 5 (36.4%) ?l/ml, while egg hatching in the control (sterile distilled water) was 44.5%. This is the first report of lactic acid as an ovicidal compound, and it may be considered as an alternative of chemical pesticide against root-knot nematodes. PMID:25085571

Lee, Yong Seong; Naning, Kyaw Wai; Nguyen, Xuan Hoa; Kim, Sun Bae; Moon, Jae Hak; Kim, Kil Yong

2014-11-28

318

Effects of catechins and low temperature on embryonic development and hatching in Heterodera glycines and Meloidogyne incognita  

Science.gov (United States)

Mimics of two natural influences, a chemical similar to one present in cyst nematodes and low temperature exposure of nematode eggs, were evaluated for their effects on quantitative and qualitative features of embryonic development and hatching. The polyphenol epigallocatechin gallate (EGCG), an ana...

319

Tolerance to Rotylenchulus reniformis and Resistance to Meloidogyne incognita Race 3 in High-Yielding Breeding Lines of Upland Cotton  

OpenAIRE

Field experiments in 1992 and 1994 were conducted to determine the effect of Rotylenchulus reniformis, reniform nematode, on lint yield and fiber quality of 10 experimental breeding lines of cotton (Gossypium hirsutum) in untreated plots or plots fumigated with 1,3-dichloropropene. Controls were La. RN 1032, a germplasm line possessing some resistance to R. reniformis, and Stoneville 453, a cultivar that is susceptible to reniform nematode. Several breeding lines produced greater lint yields ...

Cook, C. G.; Robinson, A. F.; Namken, L. N.

1997-01-01

320

Host Status of Crotalaria juncea, Sesamum indicum, Dolichos lablab, and Elymus glaucus to Meloidogyne javanica  

OpenAIRE

Reproduction of Meloidogyne javanica on Crotalaria juncea PI 207657 and cv. Tropic Sun, Sesamum indicum, Dolichos lablab, and Elymus glaucus was assessed using a root-gall index, a reproductive index obtained by dividing the final population of juveniles (J2) in soil by the initial J2 population (Pf/Pi), and the number of J2 per gram of root recovered from roots by mist chamber extraction. Lycopersicon esculentum (cv. UC 204 C) was included as a susceptible host. The root-gall index and soil ...

Araya, M.; Caswell-chen, E. P.

1994-01-01

321

ROOT-KNOT NEMATODE RESISTANCE IN PEARL MILLETS FROM WEST AND EAST AFRICA  

Science.gov (United States)

Resistance to Meloidogyne incognita is important to provide stability to pearl millet production and to reduce nematode populations that can damage crops grown in rotation with pearl millet. The objectives of this study were to determine if resistance to M. incognita exists in pearl millets from Wes...

322

Biological Control of Meloidogyne hapla Using an Antagonistic Bacterium.  

Science.gov (United States)

We examined the efficacy of a bacterium for biocontrol of the root-knot nematode (RKN) Meloidogyne hapla in carrot (Daucus carota subsp. sativus) and tomato (Solanum lycopersicum). Among 542 bacterial isolates from various soils and plants, the highest nematode mortality was observed for treatments with isolate C1-7, which was identified as Bacillus cereus based on cultural and morphological characteristics, the Biolog program, and 16S rRNA sequencing analyses. The population density and the nematicidal activity of B. cereus C1-7 remained high until the end of culture in brain heart infusion broth, suggesting that it may have sustainable biocontrol potential. In pot experiments, the biocontrol efficacy of B. cereus C1-7 was high, showing complete inhibition of root gall or egg mass formation by RKN in carrot and tomato plants, and subsequently reducing RKN damage and suppressing nematode population growth, respectively. Light microscopy of RKN-infected carrot root tissues treated with C1-7 showed reduced formation of gall cells and fully developed giant cells, while extensive gall cells and fully mature giant cells with prominent cell wall ingrowths formed in the untreated control plants infected with RKNs. These histopathological characteristics may be the result of residual or systemic biocontrol activity of the bacterium, which may coincide with the biocontrol efficacies of nematodes in pots. These results suggest that B. cereus C1-7 can be used as a biocontrol agent for M. hapla. PMID:25289015

Park, Jiyeong; Seo, Yunhee; Kim, Young Ho

2014-09-01

323

Control of Heterodera carotae, Ditylenchus dipsaci, and Meloidogyne javanica with Fumigant and Nonfumigant Nematicides  

OpenAIRE

Five field trials were conducted in Italy in 1983 and 1984 to test the efficacy of isazofos and benfuracarb in controlling Heterodera carotae on carrot, Ditylenchus dipsaci on onion, and Meloidogyne javanica on tomato. Methyl isothiocyanate (MIT) was tested against H. carotae and M. javanica. Single (10 kg a.i./ha) and split (5 + 5 kg a.i./ha) applications of isazofos gave yield increases of carrot and onion similar to those obtained with DD (300 liters/ha) and aldicarb (10 kg a.i./ha). Popul...

Greco, N.; Elia, F.; Brandonisio, A.

1986-01-01

324

Effect of Inocula Levels of Meloidogyne javanica and Sclerotium rolfsii on the Growth, Yield and Galling Incidence of Soybean  

Directory of Open Access Journals (Sweden)

Full Text Available The experiment was conducted both in the laboratory and glasshouse of the Department of Plant Pathology, BAU, Mymensingh during the period of March to July, 2001. Mixed inocula of Meloidogyne javanica and Sclerotium rolfsii in five different treatments including control were tested on the growth, yield, galling incidence and development of the nematode in soybean. Maximum length of shoot and root, fresh weight of shoot and root with nodules, number of pods, number of nodules and yield per plant were observed with the control treatment. Progressively higher galling incidence and higher number of adult females and juvenile populations of Meloidogyne javanica correspondingly with lower plant growth, nodulation and yield per plant were recorded from lower to higher levels of inocula ranging from 4-10 eggmasses of M. javanica with 0.025-0.1% w/w of S. rolfsii. Galling incidence was negatively correlated with plant growth, nodulated and yield of soybean.

K.M. Khalequzzaman

2003-01-01

325

Efecto de poblaciones de Meloidogyne sp. en el desarrollo y rendimiento del tomate  

Scientific Electronic Library Online (English)

Full Text Available SciELO Costa Rica | Language: Spanish Abstract in spanish Efecto de poblaciones de Meloidogyne sp. en el desarrollo y rendimiento del tomate. El objetivo de este trabajo fue determinar el efecto de la población inicial de Meloidogyne sp. en el cultivo del tomate. El estudio se realizó en León, Nicaragua en el año 2011. Las variables medidas fueron número d [...] e nematodos al trasplante y al momento de la cosecha, altura de la planta al momento de la madurez fisiológica y el rendimiento en kilogramos. La extracción de nematodos se realizó mediante el método de Baermann modificado. En el estudio, la densidad inicial (Pi) presentó una correlación lineal positiva con la densidad final (Pf). Sin embargo, se observó que cuando la Pi era igual a 400 nematodos/100 g de suelo, el factor de reproducción se incrementaba a 3,64; por el contrario, cuando la Pi era igual a 700 nematodos/100 g de suelo, el factor de reproducción se reducía a 2,48. La Pi se correlacionó inversamente con el peso de frutos y altura de las plantas. Plantas con 200 nematodos/100 g de suelo presentaban peso de frutos de 2,19 kg y altura de 153,20 cm en comparación con 0,93 kg y 135,24 cm en plantas con 600 nematodos/100 g de suelo. Existió una correlación positiva entre Pi y Pf de Meloidogyne sp. en el tomate. Las poblaciones de este nematodo, se correlacionaron inversamente con las variables altura y peso de los frutos. Abstract in english Effect of Meloidogyne sp. on growth and yield of tomato. The objective of this work was to determinate the relationship between initial density and final density of Meloidogyne sp in tomato crop. The study was carried out at León, Nicaragua during 2011. The variables measured were number of nematode [...] s at transplant, number of nematodes at harvest time, height at maturity of plants and yield in kilograms. Nematode extraction was performed through the Baermann modified method. In the study, the initial density (Pi) showed a positive linear correlation with the final density (Pf). However, it was observed that when Pi was equal to 400 nematodes/100 g of soil, the reproduction factor was increased to 3.64, on the contrary, when Pi was equal to 700 nematodes/100 g of soil, reproduction factor was reduced to 2.48. Pi was inversely correlated to weight of tomato fruits and height of plants. Plants with 200 nematodes/100 g of soil had fruit weight 2.19 kg and height 153.20 cm compared to 0.93 kg and 135.24 cm in plants with 600 nematodes/100 g of soil. There was a positive correlation between Pi and Pf of Meloidogyne sp. in tomatoes. The populations of this nematode, were inversely correlated with plant height and fruits weight.

Wilber, Salazar-Antón; Tomás de Jesús, Guzmán-Hernández.

2013-12-01

326

Resistência de goiabeiras e araçazeiros a Meloidogyne mayaguensis / Resistance of guava and araça to Meloidogyne mayaguensis  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese O objetivo deste trabalho foi identificar espécies de Myrtaceae resistentes a Meloidogyne mayaguensis. Acessos de araçazeiros e goiabeiras da Coleção de Plantas Frutíferas Nativas e Exóticas da Unesp/FCAV e acessos de araçazeiro de fragmentos de matas nativas do Nordeste do Estado de São Paulo e Tri [...] ângulo Mineiro foram testados quanto à resistência ao nematódeo. As mudas receberam 4.000 ovos e juvenis de segundo estádio de M. mayaguensis por planta e foram conduzidas em casa de vegetação. Aos 150 dias, os genótipos foram avaliados quanto à resistência ao nematódeo com base no fator de reprodução. Três acessos de Psidium e um de Eugenia foram resistentes a M. mayaguensis. Abstract in english The objective this work was to identify Myrtaceae species resistant to Meloidogyne mayaguensis. Araça and guava accessions obtained from the Collection of Native and Exotic Fruitful Plants of Unesp/FCAV, and accessions of araça plant obtained from native forest fragments located in the northeast reg [...] ion of the São Paulo state and the Triângulo Mineiro region, Minas Gerais state, Brazil, were tested for resistance to M. mayaguensis. The seedlings received 4,000 eggs and second stadium juveniles of M. mayaguensis each and were reared in a greenhouse. After 150 days, the genotypes were evaluated for resistance to the nematode based on the reproduction factor. Three Psidium spp. and one Eugenia accessions were resistant to M. mayaguensis.

Eduardo José de, Almeida; Jaime Maia dos, Santos; Antonio Baldo Geraldo, Martins.

2009-04-01

327

Reação de linhagens de feijão-vagem ao Meloidogyne javanica e M. paranaensis em casa-de-vegetação = Reaction of snap bean to Meloidogyne javanica and M. paranaensis in greenhouse.  

Directory of Open Access Journals (Sweden)

Full Text Available 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 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 10replications 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 0.02to 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.

Fernando César Baida

2011-04-01

328

Reação de linhagens de feijão-vagem ao Meloidogyne javanica e M. paranaensis em casa-de-vegetação / Reaction of snap bean to Meloidogyne javanica and M. paranaensis in greenhouse  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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', 'H [...] av 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 Abstract in english 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 parasi [...] tism 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

Fernando César, Baida; Débora Cristina, Santiago; Lúcia Sadayo Assari, Takahashi; João Carlos, Athanázio; Marina Capparelli, Cadioli; Ricardo Michael, Levy.

2011-06-01

329

Efeito de indutores de resistência sobre Meloidogyne exigua do cafeeiro / Effect of resistance inducers on Meloidogyne exígua of coffee  

Scientific Electronic Library Online (English)

Full Text Available A possibilidade de manejo de Meloidogyne exigua Goeldi, 1887, pela ativação de mecanismos de defesa no cafeeiro representa uma alternativa potencialmente útil no manejo desse patógeno. Com este trabalho, objetivou-se avaliar a eclosão e mortalidade de juvenis do segundo estádio (J2) de M. exigua na [...] presença de produtos indutores de resistência e avaliar o efeito do acibenzolar-S-metil (ASM, Bion®) na indução de resistência do cafeeiro (Coffea arabica L.) 'Catuaí- 144' contra M. exigua. A eclosão e mortalidade do J2 foram avaliadas no ASM e ácido salicílico (AS) nas dosagens de 0,2; 0,35 e 0,5 g. i. a./L; e no fosfito de potássio (Hortifós® PK) e silicato de potássio (Supa-potássio®) nas dosagens 5,0; 7,5 e 10,0 mL/L, empregando água e aldicarbe como testemunhas. No segundo ensaio o ASM (0,2 g i.a./L) foi aplicado na quantidade de 125 mL por planta de 'Catuaí-144' com um ano de idade, via pulverização foliar e diretamente ao solo aos 7 dias antes da inoculação e aos 2 e 7 dias após a inoculação de aproximadamente 7000 ovos de M. exigua/planta. Foram utilizadas 8 plantas/tratamento/bloco, totalizando 6 tratamentos (3 épocas de aplicação do ASM), testemunhas absoluta e inoculada, em 4 blocos. Aos 90 dias da inoculação, foi feita a avaliação da população final (número de ovos e juvenis de M. exigua), número de galhas, fator de reprodução (população final/população inicial) e peso da matéria fresca da raiz. A dosagem dos produtos não influenciou a eclosão e mortalidade dos J2 de M. exigua. Menor eclosão dos J2 de M. exigua ocorreu igualmente no Supa-potássio® e ácido salicílico, enquanto que a eclosão no ASM e na água foi igual (P Abstract in english The parasitism of coffee roots by Meloidogyne exigua Goeldi, 1887, widespread nematode in the main producing regions, can provoke a series of modifications in the normal development of the plant. The induction of resistance for the activation of existing latent mechanisms of defense in plants repres [...] ents a potentially useful alternative for the management of M. exigua in coffee plantations. In a first assay, the present work aimed at evaluating hatching and mortality of second stage juveniles (J2) of M. exigua in solutions of acibenzolar-S-metil (ASM, Bion®) and salicylic acid (SA) at the dosages of 0.2, 0.35 and 0.5 g. of a. i./L and Supa-potássio® (potassium silicate), Hortifós® PK (potassium phosphite) at the dosages 5.0; 7.5 and 10.0 mL/L, using water and aldicarb as control. The effect of ASM (0.2 g of a.i./L) was also evaluated by foliar and drench applications at 7 days before inoculation and at 2 and 7 days after inoculation of 7000 eggs of M. exigua/plant. The hatching of M. exigua J2 was inhibited in potassium silicate and in salicylic acid solutions independent of the used dosage, while J2 hatching in ASM and water was equal and significantly lower than J2 hatching verified in potassium phosphite. The mortality of J2 in SA was next to 100% and equal to the observed in aldicarb (500 ppm). The remaining products caused the same mortality of J2, however lesser than the observed in water. At ninety days of the inoculation of M. exigua on seedlings, the final population (number of eggs + J2), number of galls, reproduction factor (final population/initial population) and fresh weight of roots of plants treated with ASM did not differed significantly from control (inoculated plants).

Sônia Maria de Lima, Salgado; Mário Lúcio Vilela, Resende; Vicente Paulo, Campos.

1007-10-01

330

Efeito de indutores de resistência sobre Meloidogyne exigua do cafeeiro Effect of resistance inducers on Meloidogyne exígua of coffee  

Directory of Open Access Journals (Sweden)

Full Text Available A possibilidade de manejo de Meloidogyne exigua Goeldi, 1887, pela ativação de mecanismos de defesa no cafeeiro representa uma alternativa potencialmente útil no manejo desse patógeno. Com este trabalho, objetivou-se avaliar a eclosão e mortalidade de juvenis do segundo estádio (J2 de M. exigua na presença de produtos indutores de resistência e avaliar o efeito do acibenzolar-S-metil (ASM, Bion® na indução de resistência do cafeeiro (Coffea arabica L. 'Catuaí- 144' contra M. exigua. A eclosão e mortalidade do J2 foram avaliadas no ASM e ácido salicílico (AS nas dosagens de 0,2; 0,35 e 0,5 g. i. a./L; e no fosfito de potássio (Hortifós® PK e silicato de potássio (Supa-potássio® nas dosagens 5,0; 7,5 e 10,0 mL/L, empregando água e aldicarbe como testemunhas. No segundo ensaio o ASM (0,2 g i.a./L foi aplicado na quantidade de 125 mL por planta de 'Catuaí-144' com um ano de idade, via pulverização foliar e diretamente ao solo aos 7 dias antes da inoculação e aos 2 e 7 dias após a inoculação de aproximadamente 7000 ovos de M. exigua/planta. Foram utilizadas 8 plantas/tratamento/bloco, totalizando 6 tratamentos (3 épocas de aplicação do ASM, testemunhas absoluta e inoculada, em 4 blocos. Aos 90 dias da inoculação, foi feita a avaliação da população final (número de ovos e juvenis de M. exigua, número de galhas, fator de reprodução (população final/população inicial e peso da matéria fresca da raiz. A dosagem dos produtos não influenciou a eclosão e mortalidade dos J2 de M. exigua. Menor eclosão dos J2 de M. exigua ocorreu igualmente no Supa-potássio® e ácido salicílico, enquanto que a eclosão no ASM e na água foi igual (P The parasitism of coffee roots by Meloidogyne exigua Goeldi, 1887, widespread nematode in the main producing regions, can provoke a series of modifications in the normal development of the plant. The induction of resistance for the activation of existing latent mechanisms of defense in plants represents a potentially useful alternative for the management of M. exigua in coffee plantations. In a first assay, the present work aimed at evaluating hatching and mortality of second stage juveniles (J2 of M. exigua in solutions of acibenzolar-S-metil (ASM, Bion® and salicylic acid (SA at the dosages of 0.2, 0.35 and 0.5 g. of a. i./L and Supa-potássio® (potassium silicate, Hortifós® PK (potassium phosphite at the dosages 5.0; 7.5 and 10.0 mL/L, using water and aldicarb as control. The effect of ASM (0.2 g of a.i./L was also evaluated by foliar and drench applications at 7 days before inoculation and at 2 and 7 days after inoculation of 7000 eggs of M. exigua/plant. The hatching of M. exigua J2 was inhibited in potassium silicate and in salicylic acid solutions independent of the used dosage, while J2 hatching in ASM and water was equal and significantly lower than J2 hatching verified in potassium phosphite. The mortality of J2 in SA was next to 100% and equal to the observed in aldicarb (500 ppm. The remaining products caused the same mortality of J2, however lesser than the observed in water. At ninety days of the inoculation of M. exigua on seedlings, the final population (number of eggs + J2, number of galls, reproduction factor (final population/initial population and fresh weight of roots of plants treated with ASM did not differed significantly from control (inoculated plants.

Sônia Maria de Lima Salgado

2007-08-01

331

Dicty_cDB: SHG483 [Dicty_cDB  

Lifescience Database Archive (English)

Full Text Available SH (Link to library) SHG483 (Link to dictyBase) - - - - - (Link to Original site) SHG483F 577 - ... nce. 38 1.2 2 AW871630 |AW871630.1 ra80c01.y1 Bird-Rao ... Meloidogyne incognita J2 Meloidogyne incognita cDN ... nce. 44 3.5 1 AW871214 |AW871214.1 ra56d01.y1 Bird-Rao ... Meloidogyne incognita J2 Meloidogyne incognita cDN ... nce. 44 3.5 1 AW829376 |AW829376.1 ra39d01.y1 Bird-Rao ... Meloidogyne incognita J2 Meloidogyne incognita cDN ...

332

Reação de genótipos e híbridos de tomateiro à Meloidogyne enterolobii / Reaction of tomato genotypes and hybrids to Meloidogyne enterolobii  

Scientific Electronic Library Online (English)

Full Text Available A meloidoginose tem sido considerada uma das mais importantes doenças da cultura do tomate. O uso de tomateiros resistentes ao nematoide das galhas é medida bastante utilizada no controle de diferentes espécies, entretanto, a reação de tomateiros à Meloidogyne enterolobii ainda é pouco conhecida. Po [...] rtanto, objetivou-se a determinação da reprodução de M. enterolobii em dez híbridos de tomate (Absoluto, Cascade, Cordillera, Donatto, Ellen, Fascínio, Laura, Marguerita, Nícolas e Sanni) e dois genótipos experimentais (05 tom0041 e 08 tom00345). Os ensaios foram conduzidos em casa de vegetação e em BOD (25°C), com cinco e três repetições por tratamento, respectivamente. A infestação do substrato foi realizada com 5.000 ovos e eventuais juvenis de segundo estádio de M. enterolobii/vaso, dois dias após o transplante das plântulas. A avaliação do índice de galhas, índice de massa de ovos, população final e fator de reprodução foi realizada 60 dias após a inoculação. Em ambos os ensaios, verificou-se a suscetibilidade de todos os genótipos e híbridos avaliados. Abstract in english The diseases caused by root-knot nematodes on tomato have been considered as the most dangerous for this crop. This research aimed to study the reaction of ten tomato hybrids (Absoluto, Cascade, Cordillera, Donatto, Ellen, Fascínio, Laura, Marguerita, Nícolas and Sanni) and two genotypes (05 tom0041 [...] and 08 tom00345) to M. enterolobii. The experiments were developed out separately in a greenhouse and BOD (25°C). The substrate inoculation was made with 5,000 eggs and second stage juveniles of M. enterolobii. The variables gall and egg mass indexes, final population and the reproduction factor were determined 60 days after inoculation. On both experiments, all the genotypes and hybrids were susceptible to M. enterolobii.

Juliana Magrinelli Osório, Rosa; Juliana Nogueira, Westerich; Silvia Renata Siciliano, Wilcken.

1166-11-01

333

Ocorrência de Meloidogyne ethiopica no Paraná e reação de cultivares de batata ao nematoide das galhas / Meloidogyne ethiopica report in Parana state, Brazil, and reaction of potato cultivars to root-knot nematode  

Scientific Electronic Library Online (English)

Full Text Available Plantas de batata das cultivares Agata e Caesar debilitadas, com sistema radicular repleto de galhas e empipocamento severo nos tubérculos causado pelo nematoide das galhas (Meloidogyne sp.), foram detectadas em Contenda, município produtor tradicional do estado do Paraná. Posteriormente, fêmeas ad [...] ultas do nematoide foram extraídas das raízes e tubérculos e submetidas à eletroforese identificando-se Meloidogyne ethiopica (Est E3) pelo perfil das bandas esterásticas reveladas. Utilizando-se uma população pura de M. ethiopica, plantas de batata de diferentes genótipos, mantidas em casa de vegetação em vasos contendo solo esterilizado, foram inoculadas com 5.000 ovos + juvenis de 2o estádio do nematoide por planta. Decorridos 55 dias da inoculação, cada planta foi avaliada quanto ao número de galhas e número de ovos, determinando-se o fator de reprodução do nematoide (FR) nos diferentes materiais testados. A cultivar Eliza comportou-se como moderadamente resistente a M. ethiopica; 'Ana', 'Bel', 'Agata' e 'Catucha', como moderadamente suscetíveis; 'Clara', 'Asterix', 'Cris' e 'Cota', suscetíveis (FR>4,00); e 'Caesar', como altamente suscetível. Abstract in english Potato plants of cultivars Agata and Caesar attacked by root-knot nematode (Meloidogyne sp.) showing root systems with multiple galls and protuberances in tubers were detected in Contenda, municipality traditionally producer of the Paraná state. Adult female of Meloidogyne sp. extracted from the pot [...] ato roots and tubers and submitted to electrophoresis showed esterastic band profile as Meloidogyne ethiopica (Est E3). Using a pure population of M. ethiopica, potato plants of different cultivars, kept in pots with sterilized soil in greenhouse, were inoculated with 5,000 eggs + second stage juvenile of the nematode. Fifty-five days after the inoculation, each plant was evaluated by counting the number of galls and eggs, and determined the nematode reproduction factor (RF) in the different tested genotypes. The cultivar Eliza behaved as moderately resistant to M. ethiopica; 'Ana', 'Bel', 'Agata', and 'Catucha', as moderately susceptible; 'Clara', 'Asterix', 'Cris', and 'Cota', susceptible; and 'Caesar', as highly susceptible.

Israel, L-Medina; Víctor, HC-Coila; Cesar B, Gomes; Arione S, Pereira; Nilceu RX, Nazareno.

2014-12-01

334

IDENTIFICACIÓN DE GENES CANDIDATOS DE PATOGENICIDAD EN LA INTERACCIÓN DE LA CEPA CENICAFE 9501 CON EL NEMÁTODO DEL NUDO RADICAL Meloidogyne spp. / IDENTIFICATION OF PATHOGENIC CANDIDATES GENES IN THE INTERACTION OF THE CENICAFE 9501 STRAIN WITH THE ROOT KNOT NEMATODE Meloidogyne spp.  

Scientific Electronic Library Online (English)

Full Text Available SciELO Colombia | Language: Spanish Abstract in spanish En 1997 se registró por primera vez el aislamiento de un hongo Hyphomycete de suelos de Chinchiná (Caldas, Colombia) atacando huevos y otros estadios biológicos de las especies de nematodos fitoparásitos Meloidogyne incognita y M. javanica provenientes de lotes comerciales con café. Debido a la impo [...] sibilidad de clasificarlo taxonómicamente en los géneros actuales, este aislamiento se ha denominado temporalmente como CENICAFE 9501. Dado su potencial como biocontrolador, se propuso identificar genes candidatos involucrados en el proceso de patogenicidad de huevos de Meloidogyne. Con este fin se construyeron librerías diferenciales mediante el método de hibridación sustractiva. La secuenciación de 188 clones obtenidos permitió identificar 80 unigenes, de los cuales el mayor porcentaje correspondió a secuencias sin homología (32%), seguidas por genes candidatos a funciones de patogénesis (22%), transporte celular (17%), síntesis de proteínas (11%) y en menor proporción aquellos involucrados con transcripción y metabolismo primario (18%). Dentro de aquellos genes que contienen marcos de lectura con homología a proteínas que intervienen en la patogenicidad se encuentran una peptidasa, un receptor para sitios de ubiquitinación, una deubiquinasa, una ubiquinona oxidoreductasa, proteína relacionada con la degradación de pared celular, glicosil hidrolasa e hidroxilasa de ácidos grasos, asi como una serin proteasa. Se hace necesaria la validación de las funciones putativas de estos genes candidatos con el fin de incrementar el conocimiento básico de la fisiología de este hongo con potencial biorregulador. Abstract in english In 1997 it was reported for the first time from soil isolation of a Hyphomycete fungus from Chinchiná ( Caldas, Colombia ), attacking eggs and other biological stages of the plant parasite nematodes Meloidogyne incognita and M. javanica, from commercial coffee plots. Due to the impossibility to clas [...] sify it taxonomically under current genera, this isolate has been labeled in the mean time as CENICAFE 9501. Given its potential as biological control agent, the identification of canditate genes involved in pathogenicity processes on Meloidogyne eggs was proposed. With this purpose, differential libraries were constructed using the subtractive hybridization method. Sequencing of 188 clones allowed the identification of 80 unigenes, with the highest percentage corresponding to sequences without homology (32%), followed by candidate genes for pathogenesis (22%), cellular transport (17%), protein synthesis (11%) and in lesser degree those involved with transcription and primary metabolism (18%). Among those genes with reading frames showing homology to proteins involved in pathogenicity can be found a peptidase, a ubiquitination receptor, a deubiquitinase, a ubiquinone oxydoreductase, a protein related to the degradation of the cell wall, a glycosyl hydrolase and fatty acid hydrolase, as well as a serine protease. A validation of the putative function of these genes is neccesary in order to increase the basic knowledge of the physiology of this fungus with bioregulation potential.

Nadya Lorena, Cardona Bustos; Jhon Fredy, Betancur Pérez; Luis Fernando, Rivera Serna; Alvaro, Gaitán Bustamante.

2008-12-01

335

REDUÇÃO DA TAXA DE EXPANSÃO FOLIAR DE TOMATEIROS PARASITADOS POR Meloidogyne javanica  

Directory of Open Access Journals (Sweden)

Full Text Available Among the problems affecting tomato production phytopatogens are the most important.Among these, nematodes of the genus Meloidogyne cause large annual economic yield losses in tomatocultivation around the world. The knowledge of the physiological indices of growth is extremely important in theinterpretation of pathogen-host-environment relationships. This way, the effect of growing populations of M.javanica (Treub on the leaf area expansion rate (LAX during the early development of cherry tomato accesswas evaluated. The negative effects of nematodes were expressed in early development of tomato plants. Therewas linear increase in population (FP of M. javanica in all cherry tomato access as it was increased the initiallevel of nematode, resulting in reduction of linear TEAF. Thus any management practice that reduces thenematode population of soil during the growing season of tomatoes, will may favor the growth and developmentof plants and subsequently the production.Entre os problemas que mais afetam a produção do tomateiro estão os fitopatógenos. Dentreesses, os nematoides do gênero Meloidogyne causam consideráveis perdas econômicas anuais no cultivo detomate em todo o mundo. O conhecimento dos índices fisiológicos de crescimento é extremamente importantena interpretação das relações patógeno-hospedeiro-ambiente. Neste contexto, quantificou-se a influência doparasitismo de populações crescentes de M. javanica (Treub sobre a taxa expansão da área foliar (TEAF nafase de desenvolvimento inicial de acessos de tomateiro tipo cereja. Os efeitos negativos do parasitismo dosnematoides se manifestaram na fase inicial de desenvolvimento das plantas. Verificou-se crescimento linear dapopulação final (PF de M. javanica em todos os acessos de tomateiro cereja avaliados à medida que seaumentou o nível do inóculo inicial do nematoide, ocasionando redução linear da TEAF. Dessa forma, práticasde manejo que reduzam a população de nematoides do solo durante a fase vegetativa dos tomateiros, poderãofavorecer o crescimento e desenvolvimento das plantas e a consequente produção de frutos.

BELAN, Leônidas Leoni

2011-11-01

336

Effect of Inocula Level of Meloidogyne Javanica and Sclerotium rolfsii on the Growth, Yield and Galling Incidence of Groundnut  

Directory of Open Access Journals (Sweden)

Full Text Available Mixed inocula of Meloidogyne javanica and Sclerotium rolfsii in five different treatments including control were tested for the growth, yield, galling incidence and development of the nematode in groundnut. Progressively higher galling incidence and higher number of adult females and juvenile populations of M. javanica correspondingly with lower plant growth, nodulation and yield per plant were recorded from lower to higher levels of inocula ranging from 4-10 egg masses of M. javanica with 0.025 - 0.2% w/w of S. rolfsii . Galling incidence was negatively correlated with plant growth, nodulation and yield of groundnut.

A.K.M. Kamal Hasan

2003-01-01

337

Use of Trichoderma Species in the Control of Meloidogyne javanica Root Knot Nematode in Okra and Mungbean  

Directory of Open Access Journals (Sweden)

Full Text Available The efficacy of Trichoderma viride, T. harzianum, T. hamatum, T. koningii and T. pseudokoningii was tested for the control of Meloidogyne javanica, root knot nematode in okra and mungbean. Culture filtrates of Trichoderma spp., significantly reduced egg hatching and showed nematicidal activity by killing second stage juveniles of M. javanica. Soil application with conidial suspension of T. harzianum significantly reduced nematode population densities and root knot development in okra and mungbean. Apart from suppressing root knot nematode, T. harzianum also elevated plant height and fresh shoot weight of both okra and munhbean.

Imran A. Siddiqui

2001-01-01

338

Reduction of Root-Knot Nematode, Meloidogyne javanica, and Ozone Mass Transfer in Soil Treated with Ozone  

OpenAIRE

Ozone gas (O3) is a reactive oxidizing agent with biocidal properties. Because of the current phasing out of methyl bromide, investigations on the use of ozone gas as a soil-fumigant were conducted. Ozone gas was produced at a concentration of 1% in air by a conventional electrical discharge O3 generator. Two O3 dosages and three gas flow rates were tested on a sandy loam soil collected from a tomato field that had a resident population of root knot nematodes, Meloidogyne javanica. At dosages...

Qiu, Jinya Jack; Westerdahl, Becky B.; Pryor, Alan

2009-01-01

339

Importance of Temperature in the Pathology of Meloidogyne hapla and M. chitwoodi on Legumes.  

Science.gov (United States)

Effects of temperatures on the host-parasite relationships were studied for three legume species and four populations of root-knot nematodes from the western United States. The nematode populations were Meloidogyne hapla from California (MHCA), Utah (MHUT), and Wyoming (MHWY), and a population of M. chitwoodi from Utah (MCUT). The legumes were milkvetch (Astragalus cicer), alfalfa (Medicago sativa), and yellow sweet clover (Melilotus officinalis). All milkvetch plants survived inoculation with all nematode populations, while alfalfa and yellow sweet clover were more susceptible. On yellow sweet clover, MHCA was most pathogenic at 30 degrees C based on suppression of shoot growth while MHUT, MHWY, and MCUT were most pathogenic at 25 degrees C. All nematode populations suppressed growth of yellow sweet clover more than growth of milkvetch and alfalfa. The reproductive factor (Rf = final nematode population/initial nematode population) of MHCA was positively correlated (r = 0.83) with temperature between 15 degrees C and 30 degrees C. The greatest Rf occurred on alfalfa inoculated with MHCA at 30 degrees C. The Rf of MHUT, MHWY, and MCUT were positively correlated (r= 0.76, r= 0.78, and r= 0.73, respectively) with temperature between 15 degrees C and 25 degrees C. The Rf values of MHUT and MHWY were similar on all species and exceeded the Rf of MCUT at all temperatures (P < 0.05). PMID:19274139

Griffin, G D; Jensen, K B

1997-03-01

340

Suppression of Meloidogyne javanica by Conyza canadensis, Blumea obliqua, Amaranthus viridis and Eclipta prostrata  

Directory of Open Access Journals (Sweden)

Full Text Available Aqueous shoot extract of four weed species including Conyza canadensis, Blumea obliqua, Amaranthus viridis and Eclipta prostrata inhibited egg hatch and caused mortality of Meloidogyne javanica, the root-knot nematode juveniles in vitro to varying extent with A. viridis being the most effective. The efficacy of the powdered shoot material as soil organic amendment was tested against two nematode inoculum levels (2000 and 4000 J2 pot G 1 in a pot experiment. Soil amendment with the powdered shoot material generally reduced nematode population density, root-knot development and reproductive potential of M. javanica in brinjal roots. A. viridis was most effective in the suppression of root-knot nematode at both the nematode inoculum rates but caused slightly reduction in plant growth presumably owing to its allelopathic activity in soil.

Zarina Begum

2003-01-01

341

Dicty_cDB: SSB550 [Dicty_cDB  

Lifescience Database Archive (English)

Full Text Available SS (Link to library) SSB550 (Link to dictyBase) - - - Contig-U02317-1 SSB550Z (Link to Original ... nce. 44 1.4 1 AW571255 |AW571255.1 ra16b04.y2 Bird-Rao ... Meloidogyne incognita J2 Meloidogyne incognita cDN ... ces. 44 1.4 1 AW570934 |AW570934.1 ra13a02.y1 Bird-Rao ... Meloidogyne incognita J2 Meloidogyne incognita cDN ... nce. 44 1.4 1 AW570774 |AW570774.1 ra10g11.y1 Bird-Rao ... Meloidogyne incognita J2 Meloidogyne incognita cDN ... nce. 44 1.4 1 AW571311 |AW571311.1 ra16g10.y2 Bird-Rao ... Meloidogyne incognita J2 Meloidogyne incognita cDN ...

342

Dicty_cDB: VSC358 [Dicty_cDB  

Lifescience Database Archive (English)

Full Text Available VS (Link to library) VSC358 (Link to dictyBase) - - - Contig-U06283-1 VSC358Z (Link to Original ... e. 44 0.075 6 AW828708 |AW828708.1 ra73a06.y1 Bird-Rao ... Meloidogyne incognita J2 Meloidogyne incognita cDN ... ce. 46 0.43 1 AW571037 |AW571037.1 ra15d12.y1 Bird-Rao ... Meloidogyne incognita J2 Meloidogyne incognita cDN ... ce. 46 0.43 1 AW588731 |AW588731.1 ra03h10.y2 Bird-Rao ... Meloidogyne incognita J2 Meloidogyne incognita cDN ... ce. 46 0.43 1 AW571277 |AW571277.1 ra16d05.y2 Bird-Rao ... Meloidogyne incognita J2 Meloidogyne incognita cDN ...

343

Resistência de genótipos de batata a Meloidogyne javanica / Resistance of potato genotypes to Meloidogyne javanica  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese A resistência de 48 genótipos de batata brasileiros e europeus à infecção por Meloidogyne javanica foi avaliada em campo naturalmente infestado, em época seca e chuvosa, no Distrito Federal. O delineamento experimental foi o de blocos casualizados, com quatro repetições e parcelas com dez plantas. N [...] a época seca (maio a setembro), os níveis de infecção em tubérculos comerciais foram de, no máximo, 9,7%, com as temperaturas do solo variando de 13,5ºC a 27,7ºC. Na época chuvosa (novembro a março), os níveis de infecção por M. javanica variaram de 31,0% a 93,5% em tubérculos de batata em solo com temperaturas mais elevadas, de 27,0ºC a 33,0ºC. 'Achat', com maior grau de resistência a M. javanica entre os 48 genótipos de batata avaliados, apresentou porcentagem de infecção de tubérculos comerciais de 1% na época seca e de, no máximo, 31% na época chuvosa. Abstract in english The resistance of 48 Brazilian and European potato genotypes to infection by Meloidogyne javanica was evaluated in a naturally infested field, in the dry and rainy seasons in the Federal District, Brazil. The experimental design was the complete randomized block with four replicates and plots with t [...] en plants. In the dry season (May to September), the infection levels on the marketable tubers reached up to 9.7%, with the soil temperatures ranging from 13.5ºC to 27.7ºC. The levels of infection varied from 31.0% to 93.5% in the rainy season (November to March), under higher soil temperatures ranging from 27.0ºC to 33.0ºC. 'Achat' behaved as the most resistant to M. javanica among the 48 potato genotypes, and presented percentages of infection on the marketable tubers of 1% in the dry season and 31.0% in the rainy season.

João Maria, Charchar; Antônio Williams, Moita.

2001-03-01

344

Efeito do Meloidogyne javanica no crescimento da ervilha  

Directory of Open Access Journals (Sweden)

Full Text Available O nematóide-das-galhas radiculares, Meloidogyne javanica, comumente causa redução em produtividade de ervilha, Pisum sativum L., no Distrito Federal. O efeito de Meloidogyne javanica no crescimento da ervilha cv. Triofin foi avaliado em cinco níveis de inóculos: 0, 10, 100, 1.000 e 10.000 ovos/kg de solo, em casa de vegetação. Houve redução progressiva no crescimento da planta com o aumento do inóculos. O fator de multiplicação foi negativamente proporcional ao inóculo inicial. A nodulação bacteriana também foi seriamente afetada em todos os níveis de inóculo, exceto no de 10 ovos/kg do solo, que apresentou 61,63% de aumento no de número de nódulos/planta.

Sharma Ravi Datt

2000-01-01

345

Dicty_cDB: CHL626 [Dicty_cDB  

Lifescience Database Archive (English)

Full Text Available CH (Link to library) CHL626 (Link to dictyBase) - - - - - (Link to Original site) CHL626F 191 - ... es. 44 0.83 1 AW871214 |AW871214.1 ra56d01.y1 Bird-Rao ... Meloidogyne incognita J2 Meloidogyne incognita cDN ... ce. 44 0.83 1 AW829376 |AW829376.1 ra39d01.y1 Bird-Rao ... Meloidogyne incognita J2 Meloidogyne incognita cDN ...

346

Transcriptome analysis of resistant soybean roots infected by Meloidogyne javanica  

OpenAIRE

Soybean is an important crop for Brazilian agribusiness. However, many factors can limit its production, especially root-knot nematode infection. Studies on the mechanisms employed by the resistant soybean genotypes to prevent infection by these nematodes are of great interest for breeders. For these reasons, the aim of this work is to characterize the transcriptome of soybean line PI 595099-Meloidogyne javanica interaction through expression analysis. Two cDNA libraries were obtained using a...

Maria Eugênia Lisei de Sá; Marcus José Conceição Lopes; Magnólia de Araújo Campos; Luciano Vilela Paiva; Regina Maria Amorim dos Santos; Magda Aparecida Beneventi; Alexandre Augusto Pereira Firmino; Maria Fátima Grossi de Sá

2012-01-01

347

Phylogenetic Analyses of Meloidogyne Small Subunit rDNA  

OpenAIRE

Phylogenies were inferred from nearly complete small subunit (SSU) 18S rDNA sequences of 12 species of Meloidogyne and 4 outgroup taxa (Globodera pallida, Nacobbus abberans, Subanguina radicicola, and Zygotylenchus guevarai). Alignments were generated manually from a secondary structure model, and computationally using ClustalX and Treealign. Trees were constructed using distance, parsimony, and likelihood algorithms in PAUP* 4.0b4a. Obtained tree topologies were stable across algorithms and ...

Ley, Irma Tandingan; Ley, Paul; Vierstraete, Andy; Karssen, Gerrit; Moens, Maurice; Vanfleteren, Jacques

2002-01-01

348

Efeito do Meloidogyne javanica no crescimento da ervilha / Effect of Meloidogyne javanica on the growth of pea  

Scientific Electronic Library Online (English)

Full Text Available O nematóide-das-galhas radiculares, Meloidogyne javanica, comumente causa redução em produtividade de ervilha, Pisum sativum L., no Distrito Federal. O efeito de Meloidogyne javanica no crescimento da ervilha cv. Triofin foi avaliado em cinco níveis de inóculos: 0, 10, 100, 1.000 e 10.000 ovos/kg de [...] solo, em casa de vegetação. Houve redução progressiva no crescimento da planta com o aumento do inóculos. O fator de multiplicação foi negativamente proporcional ao inóculo inicial. A nodulação bacteriana também foi seriamente afetada em todos os níveis de inóculo, exceto no de 10 ovos/kg do solo, que apresentou 61,63% de aumento no de número de nódulos/planta. Abstract in english The root-knot nematode, Meloidogyne javanica commonly causes yield reduction of pea (Pisum sativum L.) in the Federal District of Brazil. The effect of M. javanica on the growth of pea cv. Triofin was studied with five inoculum levels namely 0, 10, 100, 1,000, and 10,000 eggs/kg of soil under greenh [...] ouse conditions. There was a progressive decrease in plant growth as the inoculum levels of nematode increased. The rate of nematode multiplication was inversely proportional to the inoculum level. Rhizobial nodulation was adversely affected at all the inoculum levels except for the inoculum level of 10 eggs/kg of soil which showed a 61.63% increase in number of bacterial nodules.

Ravi Datt, Sharma; Carlos Eduardo Lazarini da, Fonseca.

2000-01-01

349

Mean Dosage Stimulation Range of Allelochemicals from Crude Extracts of Cucumis africanus Fruit for Improving Growth of Tomato Plant and Suppressing Meloidogyne incognita Numbers  

OpenAIRE

Successful utilisation of allelochemicals in management of plant-parasitic nematodes depends on their degree of phytotoxicity. Conventional methods of determining phytotoxicity are tedious, with inconsistent results. Plants respond to increased dosages of allelochemicals in a density-dependent growth pattern, which allows the use of the Curve-fitting Allelochemical Response Data computer-based model to determine the mean dosage stimulation range of used allelochemicals. The CARD modelling wa...

Osvaldo Pelinganga; Phatu Mashela

2012-01-01

350

ROOT-KNOT NEMATODE RESISTANCE IN AFRICAN PEARL MILLETS  

Science.gov (United States)

Resistance to Meloidogyne incognita in pearl millet reduces nematode populations that can damage crops grown in rotations. Pearl millets from Africa were evaluated as sources of resistance. Seventeen pearl millets were evaluated as bulk (S0) populations. All African varieties expressed some level o...

351

Resistance to root-knot nematodes, Meloidogyne spp., I potato.  

OpenAIRE

Root-knot nematodes, Meloidogyne spp., are world-wide one of the most damaging pests to arable farming. In North Western Europe, the species M. chitwoodi, M. fallax and M. hapla are becoming a serious problem in potato growing areas as a result of recent changes in crop rotation, that now include highly profitable host crops, and a reduced use of nematicides in potato. The root-knot nematodes can cause yield reduction and deteriorate the quality of the tuber to an unmarketable product. Since ...

Janssen, G. J. W.

1997-01-01

352

Biology of Meloidogyne platani Hirschmann Parasitic on Sycamore, Platanus occidentalis  

OpenAIRE

The development of Meloidogyne platani on sycamore was followed for 40 days (22-28 C). Juveniles penetrated the feeder roots behind the root cap and invaded the vascular cylinder within 3 days after inoculation. All subsequent development of the nematodes and host effects occurred only within the stele. The second juvenile molt and sex differentiation occurred by the 17th day. Young females were observed by the 26th day. Eggs were observed inside the roots by the 35th day and were exposed to ...

Al-hazmi, A. S.; Sasser, J. N.

1982-01-01

353

Densidad crítica de Meloidogyne Exigua en plantas de Almácigo de café variedad Caturra  

Scientific Electronic Library Online (English)

Full Text Available SciELO Costa Rica | Language: Spanish Abstract in spanish El objetivo del estudio fue evaluar el efecto de densidad creciente de Meloidogyne exigua sobre el desarrollo de plantas de almácigo. Se trasplantaron plántulas de café variedad caturra a bolsas de polietileno con 1335 cm³ de sustrato desinfectado, para establecer un ensa-yo con diseño de bloques co [...] mpletos al azar, con 8 repeticiones. Los tratamientos aplicados consistieron de poblaciones iniciales (Pi) de 0; 0,125; 0,25; 0,5; 1; 2; 4; 8; 16; 32 y 64 huevos+J2/ cm³ de sustrato, aplicadas un mes después del trasplante. El modelo y=m+(1-m) Z P-T aplicado 234 días después del trasplante para la altura, diámetro, número de nudos y peso fresco aéreo, indicó que el límite de tolerancia (T) fue de 0,66; 0,06; 0,13 y 0,88 huevos+J2/cm³, respectivamen-te; la producción mínima relativa (m) fue de 0,79; 0,79; 0,33 y 0,54 respectivamente, a Pi iguales o mayores a 64 huevos+J2/cm³. El índice de agallas alcanzó el máximo a partir de una Pi de 2; el pico máximo de nematodos en el suelo y las raíces se alcanzó con Pi entre 2 y 4; mientras la tasa máxima de reproducción fue de 114 con Pi de 0,125. Se concluyó que la densidad crítica fue cercana a cero huevos/cm3 de sustrato como población inicial, y que el almácigo se debe desarrollar libre de nematodos, ya que aún con Pi bajas se puede alcanzar la máxima población en corto tiempo. Abstract in english Critical density of Meloidogyne exigua in nursery coffee plants, Caturra variety. The purpose of this study was to evaluate the effect of increasing density of Meloidogyne exigua on the development of nursery plants. Coffee plantlets of the Caturra variety were transplanted into polyethylene bags wi [...] th 1335 cm3 of disinfected substrate, to establish a trial with a randomized complete block design, with 8 replicates. The treatments applied included initial populations (Pi) of 0; 0,125; 0,25; 0,5; 1; 2; 4; 8; 16; 32 and 64 eggs + J2/cm ³ substrate applied one month after transplant. The model y=m+(1-m) Z P-T applied 234 days after transplant to the height, diameter, number of nodes and aerial fresh weight, indicated that the tolerance limit (T) was 0,66; 0,06; 0,13 and 0,88 eggs + J2/cm³, respectively; the relative minimum production (m) was 0,79; 0,79; 0,33 and 0,54 respectively, at Pi equal to or higher than 64 eggs + J2/cm³. The gall index reached its maximum from a Pi of 2; the maximum peak of nematodes on the soil and roots was reached with a Pi between 2 and 4 while, the maximum rate of reproduction rate was 114 with a Pi of 0,125. It was concluded that the critical density was close to zero eggs/cm3 of substrate as initial population, and the nursery plants should develop free of nematodes since, even with a low Pi; it could reach the maximum population in a short time.

Mainor, Rojas; Luis, Salazar.

2013-12-01

354

Trigonella foenum-graecum (fenugreek-mediated suppression of Meloidogyne javanica in mungbean  

Directory of Open Access Journals (Sweden)

Full Text Available Soil amendments with powdered seeds of Trigonella foenum - graecum (fenugreek caused soil suppressiveness against Meloidogyne javanica. Decomposed seeds of fenugreek caused marked reduction in nematode population densities and subsequent root-knot development as compared to the aqueous extract of the seeds indicating that some indirect factors are involved in the suppression of root-knot nematode. Both decomposed seeds and aqueous extracts enhanced plant height and fresh weights of shoot whereas root growth remained uninfluenced. Changes in fungal communities associated with nematode control were studied by comparing population numbers of fungi in the soil and in internal root tissues (endorhiza in non-amended and fenugreekamended soils. Acremonium sp., Chaetomium globosum, Fusarium solani, Macrophomina phaseolina and Rhizoctonia solani were found to colonize inner root tissues of mungbean. Acremonium sp., C. globosum and F.solani were isolated in a relatively higher frequency from roots growing in the amended soils while M. phaseolina and R. solani colonized greatly in roots growing in non-amended soil. Of the fungi isolated from soils, Penicillium brefaldianum caused maximum juvenile mortality of M.javanica whereas F.solani caused greatest inhibition of egg hatch.

Tayyaba Zia

2002-12-01

355

Low, but Strongly Structured Mitochondrial DNA Diversity in Root Knot Nematodes (Meloidogyne)  

OpenAIRE

Root-knot nematodes (genus Meloidogyne) have been the subject of recent and numerous studies of genetic variation because of the need to develop molecular diagnostics for the four globally distributed, parthenogenetic species that are significant agricultural pests. Our analysis of Meloidogyne mtDNA improves on previous studies: (i) by examining restriction site polymorphism among a large number of isolates also characterized for standard morphological, host range and allozyme phenotypes; (ii...

Hugall, A.; Moritz, C.; Stanton, J.; Wolstenholme, D. R.

1994-01-01

356

Respuesta de Zamia incognita L. al cultivo in vitro, una alternativa para su conservación  

OpenAIRE

Título en ingles: In vitro culture response on Zamia incognita,  an alternative for preservation Resumen: Las Zamiaceas son plantas relictuales consideradas fósiles vivientes. En Colombia, el 65% de esta familia se encuentra en alguna categoría de amenaza, por la destrucción del hábitat e intensa recolección. Teniendo en cuenta que entre las ventajas de la propagación in vitro está la conservación ex situ de germoplasma, el presente trabajo tuvo como objetivo evaluar el potencial de...

Urrea, Aura I.; Sonia Gomez; Naranjo, Esther J.

2012-01-01

357

Reproduction of Meloidogyne enterolobii in rootstocks and cucumber hybrids / Reprodução de Meloidogyne enterolobii em porta-enxertos e híbridos de pepino  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Este estudo teve como objetivo determinar a resistência de seis porta-enxertos para pepino (abóbora 'Menina Brasileira', moranga 'Exposição', 'Shelper', 'Tetsukabuto Takaiama', 'B8-A Tetsukabuto' e 'Excite Ikki') e quatro híbridos de pepino tipo japonês ('Yoshinari', 'Kouki', 'Taisho' e 'Tsuyataro') [...] a Meloidogyne enterolobii. O experimento foi conduzido em casa de vegetação, cada parcela constou de uma planta por vaso contendo 2 litros de solo autoclavado. Dois dias após o transplantio das mudas, cada planta foi inoculada com 5.000 ovos e juvenis de segundo estádio (população inicial = Pi) de M. enterolobii. Tomateiros 'Rutgers' foram utilizados como padrão de viabilidade do inóculo. O delineamento experimental foi inteiramente casualizado com cinco repetições por tratamento. Sessenta dias após a inoculação, cada planta foi avaliada quanto ao número total de nematoides nas raízes (população final = Pf) e fator de reprodução (FR = Pf / Pi). Todos os porta-enxertos e híbridos de pepino estudados permitiram a multiplicação de M. enterolobii, entretanto os valores do FR foram menores nos porta-enxertos 'Shelper', 'Excite Ikki KY' e 'Menina Brasileira'. Em um segundo experimento, confirmou-se o baixo valor do FR destes três porta-enxertos, porém, com valor pouco maior para 'Menina Brasileira'. Desta maneira, estes porta-enxertos podem ser recomendados em áreas infestadas com M. enterolobii, desde que em baixa população, por restringirem drasticamente a multiplicação do patógeno. Conclui-se que os porta-enxertos 'Shelper' e 'Excite Ikki KY' foram os que apresentaram os menores FR podendo ser classificados como moderadamente resistentes a este nematoide. Abstract in english This study aimed to determine the resistance of six rootstocks for cucumber (squash 'Menina Brasileira', pumpkin 'Exposição', 'Shelper', 'Tetsukabuto Takaiama', 'B8-A Tetsukabuto' and 'Excite Ikki') and four Japanese cucumber hybrids ('Yoshinari', 'Kouki', 'Taisho' and 'Tsuyataro') to Meloidogyne en [...] terolobii. The experiment was conducted in greenhouse; each plot consisted of one plant per pot containing 2 liters of autoclaved soil. The experimental design was completely randomized, with five replicates per treatment. Two days after transplanting the seedlings, each plant was inoculated with 5,000 eggs and second-stage juveniles (initial population = Pi) of M. enterolobii. Tomato 'Rutgers' was used as indicative of inoculum viability. Sixty days after inoculated, each plant was evaluated for total number of nematodes in the roots (final population = Pf) and reproduction factor (FR=Pf/Pi). All rootstocks and cucumber hybrids allowed M. enterolobii multiplication, but FR values were lower in 'Shelper', 'Excite Ikki KY' and 'Menina Brasileira' rootstocks. In a second experiment, the low FR in these three rootstocks was confirmed, but with higher values in 'Menina Brasileira'. So, these rootstocks can be recommended to M. enterolobii infested areas, but with low populations, because they don't permit great multiplication of the patogen. It is concluded that 'Shelper' and 'Excite Ikki KY' rootstocks had the lowest FR and can be classified as moderate resistant to this nematode.

Silvia Renata S, Wilcken; Juliana MO, Rosa; Juliana N, Westerich; Maria José de M, Garcia; Antonio Ismael Inácio, Cardoso.

2013-12-01

358

Nematicidal activity of leaves of common shrub and tree species from Southern Chile against Meloidogyne hapla  

Scientific Electronic Library Online (English)

Full Text Available Buscando alternativas biológicas para el control del nemátodo de las agallas radicales, Meloidogyne hapla, se evaluó la incorporación al sustrato de follaje seco y molido de Buddleja globosa, Drymis winteri, Eucalyptus globulus, Gevuina avellana, Laurelia sempervirens, huma apiculata, Maytenus boari [...] a y Ugni molinae. Se utilizó como control un tratamiento sin follaje. El ensayo se realizó en macetas en las que se trasplantaron plantas de lechuga (cv Reina de Mayo). Todas las macetas se inocularon con 2000 huevos y juveniles de M. hapla y se mantuvieron por 45 días en invernadero. Los resultados indicaron que las plantas de lechuga desarrolladas en sustratos con hojas secas de L. sempervirens, G. avellana, M. boaria, D. winteri y B. globosa redujeron significativamente el agallamiento radical. Mientras que todos los tratamientos afectaron significativamente la formación de huevos y juveniles de M. hapla, destacando el efecto inhibitorio sobre este parámetro el follaje seco de U. molinae, D. winteri y L. sempervirens. En todas las especies, el incremento de la concentración de follaje incorporado al sustrato resultó en un mayor control en la multiplicación de M. hapla. Abstract in english The biological control of the root-knot nematode, Meloidogyne hapla , was evaluated through the addition of organic amendments of dry and chopped leaves of Buddleia globes, Dramas winter, Eucalyptus globules, Genuine aflame, Aurelia sempervirens, huma apiculata, Maytenus boaria and Ugni molinae to t [...] he soil substratum. The assays were carried out in pots seeded with lettuce plants (cv. Reina de Mayo). All pots were inoculated with 2000 eggs and juveniles of M. hapla, and then maintained under greenhouse conditions for 45 days. Control pots without foliage additions were also seeded with lettuce. The results show that the addition of dry leaves of L. sempervirens, G. avellana, M. boaria, D. winteri , and B. globosa significantly reduced root-knot nematode development in soil in which lettuce plants were grown. On the other hand, while all of the treatments significantly affected the development of eggs and juveniles of M hapla, the best inhibitory effect was found with dry leaves of U. molinae, D. winteri and L. sempervirens . For all plant species, an increase in the concentration of dry leaves incorporated into the substratum resulted in better control of nematode population.

Laura, Böhm; Nolberto, Arismendi; Luigi, Ciampi.

2009-08-01

359

Evaluation of the Combined Effects of Paecilomyces lilacinus and Trichoderma harzianum Against Root-knot Disease of Tomato  

OpenAIRE

The addition of Paecilomyces lilacinus and Trichoderma harzianum as nematophagous fungi separately along with organic substrate to the infested soil, sufficiently retarded the pathogenic activity of Meloidogyne incognita. Addition of Paecilomyces lilacinus and Trichoderma harzianum in combination amended with organic substrate gave the effective control of root-knot nematodes population thus reduced root-knot disease and increased plant vigour.

Hafeez Ullah Khan; Riaz Ahmad; Waqar Ahmed; Khan, S. M.; Aslam Khan, M.

2001-01-01

360

Transcriptional analysis through RNA sequencing of giant cells induced by Meloidogyne graminicola in rice roots.  

Science.gov (United States)

One of the reasons for the progressive yield decline observed in aerobic rice production is the rapid build-up of populations of the rice root knot nematode Meloidogyne graminicola. These nematodes induce specialized feeding cells inside root tissue, called giant cells. By injecting effectors in and sipping metabolites out of these cells, they reprogramme normal cell development and deprive the plant of its nutrients. In this research we have studied the transcriptome of giant cells in rice, after isolation of these cells by laser-capture microdissection. The expression profiles revealed a general induction of primary metabolism inside the giant cells. Although the roots were shielded from light induction, we detected a remarkable induction of genes involved in chloroplast biogenesis and tetrapyrrole synthesis. The presence of chloroplast-like structures inside these dark-grown cells was confirmed by confocal microscopy. On the other hand, genes involved in secondary metabolism and more specifically, the majority of defence-related genes were strongly suppressed in the giant cells. In addition, significant induction of transcripts involved in epigenetic processes was detected inside these cells 7 days after infection. PMID:23881398

Ji, Hongli; Gheysen, Godelieve; Denil, Simon; Lindsey, Keith; Topping, Jennifer F; Nahar, Kamrun; Haegeman, Annelies; De Vos, Winnok H; Trooskens, Geert; Van Criekinge, Wim; De Meyer, Tim; Kyndt, Tina

2013-09-01