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The lesion nematode Pratylenchus jaehni occurs at low frequency in Brazilian coffee orchards but could provoke extensive root damage. Intercropping cover crops is a traditional practice in Brazilian coffee orchards, and the use of non-hosts of P. jaehni as cover crops may be a useful management method. In this work, 10 cover crops were tested concerning reproduction of P. jaehni. Cajanus cajan, Canavalia ensiformis, and Mucuna deeringiana are cover crops commonly used as intercropping in coffee orchards, but they must not be used in orchards infested with P. jaehni, because they are good hosts of this nematode. Brachiaria ruziziensis, Crotalaria juncea, Dolichos lablab, and Pennisetum glaucum were considered poor hosts. Helianthus annuus cv. Catissol and cv. Uruguai and Crotalaria spectabilis proved to be non-hosts to P. jaehni, and therefore, they are the cover crops recommended in coffee orchards infested with this nematode.

Passion fruit (Passiflora spp.) yield is limited by several factors, including soil pathogens, such as Rotylenchulus reniformis (the reniform nematode) and Meloidogyne incognita (the Southern root-knot nematode). Understanding the behavior of different cultivars, within different species of passion fruit could be important asset to the search for sources of resistance, and therefore for the effective management of phytonematodes. Three trials were carried out in greenhouse to evaluate the resistance/susceptibility of different passion fruit species to R. reniformis and M. incognita. For R. reniformis, cultivars from two species were tested: Passiflora edulis f. flavicarpa (‘BRS Sol do Cerrado’, ‘BRS Rubi do Cerrado’ and ‘BRS Gigante Amarelo’) and Passiflora cincinnata (‘BRS Sertão Forte’). Regarding M. incognita, all the cultivars above were evaluated, with the addition of Passiflora setacea (‘BRS Pérola do Cerrado’). The results showed that all tested cultivars were susceptible to the reniform nematode. Conversely, all tested cultivars were immune to root-knot nematode, although exhibiting root galling. Therefore, it is emphasizes the relevance of reniform nematode to passion fruit crops. Resumo A produção do maracujazeiro (Passiflora spp.) é limitada por vários fatores, incluindo patógenos de solo, como Rotylenchulus reniformis (nematoide-reniforme) e Meloidogyne incognita (nematoide-das-galhas). Entender o comportamento de diferentes cultivares, pertencentes às diferentes espécies de maracujazeiro, é de fundamental importância, especialmente quando se buscam fontes de resistência para o manejo efetivo de fitonematoides. Dois ensaios foram conduzidos em casa de vegetação para avaliar a resistência/suscetibilidade de diferentes espécies de maracujazeiro a R. reniformis e M. incognita. Para R. reniformis, foram testadas cultivares pertencentes a duas espécies: Passiflora edulis f. flavicarpa (‘BRS Sol do Cerrado’, ‘BRS Rubi do Cerrado’ e ‘BRS Gigante Amarelo’) e P. cincinnata (‘BRS Sertão Forte’). Quanto a M. incognita, foram testadas todas as cultivares acima, além da espécie P. setacea (‘BRS Pérola do Cerrado’). Os resultados mostraram que todas as cultivares de maracujazeiro testadas foram suscetíveis ao nematoide-reniforme. Por outro lado, todas as cultivares testadas foram imunes ao nematoide-das-galhas, apesar de apresentarem galhas nas raízes. Portanto, ressalta-se a relevância do nematoide reniforme para a cultura do maracujazeiro.

Phytonematodes are among the main pathogens of the common bean. In general, control practices that aim to control these pathogens have not been regularly adopted in Brazil. The objectives of the present study were to evaluate the occurrence of phytonematodes in dry bean fields in Paraná and São Paulo states and estimate the pathogenicity of Pratylenchus brachyurus to dry bean in glasshouse experiments. Root and soil were sampled for nematode extraction, identification and estimation of population density. Four glasshouse experiments with different initial population densities were carried out to evaluate the effect of P. brachyurus on the growth of dry bean plants. Six species of phytonematodes were detected, namely Helicotylenchus dihystera, P. brachyurus, Pratylenchus crenatus, Meloidogyne javanica, Meloidogyne incognita and Rotylenchulus sp. The spiral nematode H. dihystera was found in all samples and was the most abundant species in both states. The lesion nematode P. brachyurus was also frequent, reaching 94% in Paraná and 100% in São Paulo. The root-knot nematodes and Rotylenchulus sp. were reported only in São Paulo fields (45% and 18% frequency, respectively), and P. crenatus only in Paraná (12%). The most abundant nematode in the soil was H. dihystera, and in roots was P. crenatus. It was demonstrated that densities of 6.66 specimens of P. brachyurus per cm3 of soil provoke visible and measurable root decay. In conclusion, survey data showed low phytonematode densities and pathogenicity tests demonstrated that densities above 6.67 specimens of P. brachyurus per cm3 of soil cause damage to the dry bean roots.

The lesion nematode

The root-knot nematode (Meloidogyne incognita) is one of most devastating pathogens that attack the common bean crop. Although there is evidence that some cultivars have race-specific resistance against M. incognita, these resistance sources have not proved effective, and nematodes are able to circumvent the host’s defense system. We constructed RNA-seq based libraries and used a high-throughput sequencing platform to analyze the plant responses to M. incognita. Assessments were performed at 4 and 10 days after inoculation corresponding to the stages of nematode penetration and giant cell development, respectively. Large-scale transcript mapping to the common bean reference genome (G19833) resulted in the identification of 27,195 unigenes. Of these, 797 host genes were found to be differentially expressed. The functional annotation results confirm the complex interplay between abiotic and biotic stress signaling pathways. High expression levels of the wounding-responsive genes were observed over the interaction. At early response, an overexpression of the N gene, a TIR-NBS-LRR resistance gene, was understood as a host attempt to overcome the pathogen attack. However, the repression of heat shock proteins resulted in a lack of reactive oxygen species accumulation and absence of a hypersensitive response. Furthermore, the host basal response was broken by the repression of the ethylene/jasmonate pathway later in the response, resulting in a continuous compatible process with consequent plant susceptibility.

The effect of abamectin, applied as seed treatment, on Meloidogyne incognita penetration, colonization, and reproduction on cotton was evaluated in two greenhouse experiments. Second stage juveniles (J2) penetration was evaluated 3, 9 and 15 days after germination (dag), whereas the nematode colonization was evaluated 27dag, by counting the total number of galls and egg masses per root system. Eggs and J2 were extracted from the roots to assess the nematode reproduction at 50 and 100dag. The seed treatment caused a decrease in J2 penetration in the roots, resulting in lower colonization and reproduction of M. incognita. These findings are discussed considering the environmental aspects of abamectin in the soil and the current practices for the crop management.O efeito de abamectina em tratamento de sementes na penetração, colonização e reprodução de Meloidogyne incognita, em algodão, foi avaliado em dois experimentos de casa de vegetação. A penetração de juvenis de segundo estádio (J2) foi avaliada aos três, nove e 15 dias após a germinação (dag), enquanto que a colonização 27dag foi avaliada por meio da contagem do número total de galhas e massas de ovos por sistema radicular. Ovos e J2 de M. incognita foram extraídos das raízes para determinar a reprodução do nematoide aos 50 e 100dag. O tratamento de sementes diminuiu a penetração dos J2 nas raízes, resultando em menor colonização e reprodução de M. incognita. Os resultados obtidos são discutidos tendo em vista os aspectos ambientais da presença de abamectina no solo e as práticas agrícolas em uso.

Trinta e nove espécies de nematóides fitoparasitos foram identificadas no “Campus” Luiz de Queiroz (22º42’33” S, 47º38’00” WG, Piracicaba, São Paulo, Brasil), das quais 17 na vegetação nativa. A maior parte destas, provavelmente autóctones, desapareceu ou tornou-se rara quando a vegetação nativa foi substituída pelas plantas do parque da ESALQ ou por plantas cultivadas. As famílias mais bem representadas foram Hoplolaimidae e Criconematidae. Dezoito espécies raras ou pouco freqüentes no Brasil, inclusive 2 novas espécies (Trophurus n. sp. e Criconema n. sp.), foram identificadas. O presente trabalho estudou pormenorizadamente algumas delas (Xiphidorus minor, Paratrichodorus anthurii, Rotylenchus caudaphasmidius, Criconema braziliense, Ogma cataracticum, Criconemella palustres, Criconemella sp., Discocriconemella mineira, D. repleta e as 2 novas espécies). Thirty nine species of plant parasitic nematodes were identified at Luiz de Queiroz “campus” (22º42’30” S, 47º38’00” WG, Piracicaba, São Paulo State, Brazil). Seventeen species were collected from native vegetation and were probably native from this area. Most of these species disappeared or became rare when the native vegetation was replaced by plants of ESALQ park or cultivated plants. The most frequently nematodes collected belonged to Hoplolaimidae and Criconematidae. Eighteen rare species, including 2 new species (Trophurus n. sp. and Criconema n. sp.), were identified. The present work studied some of them (Xiphidorus minor, Paratrichodorus anthurii, Rotylenchus caudaphasmidius, Criconema braziliense, Ogma cataracticum, Criconema palustres, Criconemella sp., Discocriconemella mineira, D. repleta and the 2 new species) in detail.

Os danos causados pelo nematóide cavernícola, Radopholus similis (Cobb, 1893) Thorne 1949, à cultura da banana podem ser evitados com o plantio de mudas sadias em solos não infestados. Infelizmente, devido à presença desse nematóide nas principais áreas produtoras do Brasil, a obtenção de grandes quantidades de material de plantio sadio somente pode ser feita através da desinfestação das mudas disponíveis. Neste trabalho foi estudada a eficiência dos três principais métodos de desinfestação de mudas: o descorticamento do rizoma, o tratamento com água quente e o tratamento com nematicidas. Foram utilizadas mudas de bananeira Nanicão (Musa acuminata, triplóide AAA) dos tipos "chifrão" e muda adulta, provenientes de uma plantação infestada. A avaliação foi feita 3-4 e 7-9 meses após o tratamento das mudas, através da extração e contagem dos nematóides presentes nas raízes. Verificou-se que a retirada de todo o tecido necrosado das mudas resultou na eliminação da maior parte dos nematóides, tendo restado uma infestação residual em algumas das plantas. A erradicação dos nematóides foi obtida quando o descorticamento foi seguido pela imersão das mudas em água quente a 55° C por 20, 30 ou 40 minutos, ou em carbofurano a 1,0 ou 3,0%, em aldoxicarbe a 0,5, 1,0 ou 3,0% ou em oxamil a 0,5, 1,0 ou 3,0%. Os tratamentos das gemas de bananeira Nanicão com água quente não foram satisfatórios, pois poucas sobreviveram TThe damage caused by the burrowing nematode, (Radopholus similis) (Cobb, 1893) Thorne, 1949, on banana can be prevented by planting nematode-free material in uninfested lands. Unfortunately, due to the prevalence of such nematode in the principal banana growing areas of Brazil, large quantities of clean sets can not be obtained unless preplant treatments are employed. In this work it was studied the efficiency of the three most used preplant treatments for disinfesting banana sets (paring, hot water and chemical dip). Spearpoints and maiden heads of Giant Cavendish (Musa acuminate, triploid AAA) from and infested banana plantation were used. The efficiency of the treatments was assessed 3-4 and 7-9 months later by recovering and counting the root nematodes. Paring all visible necrotic tissues away was enough to eliminate most of nematodes, but a residual population remained in some plants. The eradication was achieved when the paring was followed by dipping in hot water at 55° C for 20, 30 or 40 minutes, or in 1.0 or 3.0% carbofuran, 0.5, 1.0 or 3.0% aldoxicarb or 0.5, 1.0 or 3.9% oxamyl for 30 minutes. Hot water treatment of buds of Giant Cavendish banana did not show good results, because only few of them have survived

Made available in DSpace on 2013-09-27T16:24:20Z (GMT). No. of bitstreams: 1 ZOORECZOOR14510062114.pdf: 155921 bytes, checksum: 66ba8abb7034d1675ec01d011f35f2ab (MD5) Previous issue date: 2008-09-01 Made available in DSpace on 2013-09-30T19:25:01Z (GMT). No. of bitstreams: 1 ZOORECZOOR14510062114.pdf: 155921 bytes, checksum: 66ba8abb7034d1675ec01d011f35f2ab (MD5) Previous issue date: 2008-09-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:34:55Z No. of bitstreams: 1 ZOORECZOOR14510062114.pdf: 155921 bytes, checksum: 66ba8abb7034d1675ec01d011f35f2ab (MD5) Made available in DSpace on 2014-05-20T15:34:55Z (GMT). No. of bitstreams: 1 ZOORECZOOR14510062114.pdf: 155921 bytes, checksum: 66ba8abb7034d1675ec01d011f35f2ab (MD5) Previous issue date: 2008-09-01 Wilcken, S.R.S., E.S. Mori, M. Bacci, L.C.C.B. Ferraz, C.M.G. Oliveira & M.M. Inomoto. 2008. Relationships among Pratylenchus jaehni and P. coffeae populations from Brazil. The relationships among Pratylenchus jaehni (C) and six amphimitic Pratylenchus populations from Brazil (three from banana, PcB1, PcB2, and PcB3; one from Aglaonema sp., M2; one from coffee, K5; and one from citrus, C) were studied through morphological and molecular analysis, and pathogenicity test. The analysis of morphometric characteristics of PcB1, M2, C2 and K5, compared with P. jaehni and P. coffeae (K6) data obtained from literature, delineated three groups: P. coffeae (K6), PcB1 and M2; P. jaehni (C1) and C2; and K5. RAPD analysis of PcB1, PcB2, PcB3, M2, C2, K5 and P.jaehni (C1) demonstrated that these populations form three distinct genetic groups: PcB1, PcB2, PcB3 and M2; P.jaehni and C2; and K5. In pathogenicity test, K5 reproduced well on coffee and caused extensive root necrosis, but C2 did not. Population C2 reproduced well on Rangpur lime, which was previously rated as poor host to K5. Therefore, the results demonstrated that C2 is P. jaehni, K5 is an undescribed species of Pratylenchus, and PcB1, PcB2 and PcB3 are P. coffeae. The taxonomic status of M2 remains inconclusive. Univ Estadual Paulista, FCA UNESP, BR-18603070 Botucatu, SP, Brazil Univ Estadual Paulista, FCA UNESP, BR-18603070 Botucatu, SP, Brazil

Para a cultura da cana-de-açúcar, diferentes manejos e tratos culturais são utilizados como: aplicação de vinhaça, torta de filtro, cama de frango e adubação química, podendo levar a modificações da temperatura, umidade, concentração de nutrientes minerais e teores de matéria orgânica. Porém são escassas as informações quanto à ocorrência e freqüência de nematóides em diferentes tipos de solo sob diferentes práticas de manejo e tempo de cultivo, em lavouras canavieiras. Assim, o presente estudo foi desenvolvido com os objetivos de: quantificar a população e identificar os gêneros de fitonematóides em cana-de-açúcar em áreas sob diferentes práticas de cultivo; e quantificar a população de bactérias totais, fungos totais, actinomicetos, fungos e bactérias celulolíticas e solubilizadoras de fosfato. O estudo foi desenvolvido em lavouras de cana-de-açúcar, localizadas no município de Bandeirantes ? PR. Foram avaliadas sete áreas sob cultivo de cana-de-açúcar sob diferentes manejos com aplicação de: 1) vinhaça em solo LVe com textura argilosa em cana-planta; 2) vinhaça em solo (LVe) com textura argilosa em cana-soca; 3) vinhaça em solo (RU) com textura média em cana-soca; 4) torta de filtro em solo (LVe) com textura argilosa em cana-soca; 5) adubação química em solo (LVe) com textura argilosa em cana-planta; 6) adubação química em solo (LVe) com textura argilosa em cana-soca; 7) adubação química em solo (RU) com textura média em cana-soca; e 8) área sob vegetação secundária nativa, solo (LVe) com textura argilosa adotada como referência para comparação. Cada área foi georreferenciada com auxílio de receptor GPS (Sistema de Posicionamento Global), delimitando-se três parcelas com um hectare em cada uma das áreas representativas, distribuídas em delineamento inteiramente casualizado. Foram realizadas duas amostragens, sendo uma em setembro de 2007, período seco, e a segunda em março de 2008, período chuvoso. Foram colhidas 15 sub-amostras de solo e raiz da região rizosférica a uma profundidade de 0 - 30 cm, obtendo-se uma amostra composta em cada parcela. Após identificadas e acondicionadas em sacos escuros de polietileno, foram mantidas sob refrigeração até o momento das análises. Observou-se que a adubação orgânica pela adição de vinhaça e torta de filtro favorece o aumento da população de nematóides de vida livre. Por outro lado, a adubação química, sobretudo nos solos com textura média, favorece a população de Pratylenchus sp., e contribui para as maiores populações de fungos totais, bactérias totais, solubilizadores de fosfato, actinomicetos. Na vegetação secundária nativa em solo com textura argilosa, considerada como área referência, foram encontrados o maior número do nematóide do gênero Mesocriconema sp., e menores populações de fungos totais, celulolíticos, solubilizadores de fosfato e de Paecilomyces sp. As populações dos diferentes gêneros de nematóides no solo ou em raízes foram maiores na amostragem de março de 2008 (período chuvoso), enquanto que a contagem de microrganismos foi significativamente superior na amostragem de outubro de 2007 (período seco). To the cultivation of sugarcane, different management and cultural tracts are used such as: application of stillage, filter cake, broiler litter and chemical fertilization, which could lead to changes in temperature, humidity, concentration of nutrients and levels of organic matter. Neverthless, the information related to the ocurrence and frequency of nematode in different kinds of soils under different practice of management and cultivation time, in sugarcane agriculture is scarse. Therefore, this study was developed with the objectives to: quantify the population and identify the phytonematode in sugarcane in areas under different practices of cultivation; and quantify the population of total bacteria, total fungi, actinomycetes, cellulolytic and phosphate solubilizing. The study was developed in sugarcane plantations, located in Bandeirantes city, in the state of Paraná. Seven areas under the cultivation of different managements were evaluated with application of: 1) vinasse in soil (LVe) with clay in the plant cane; 2) vinasse in soil (LVE) with clay in ratoon cane; 3 ) vinasse in soil (RU) with medium texture in ratoon cane; 4) filter cake in soil (LVE) with clay in ratoon cane; 5) chemical fertilizer in soil (LVE) with clay in plant cane; 6) chemical fertilizer in soil (LVE) with clay in ratoon cane; 7) fertilization on soil chemistry (RU) with medium texture in sugarcane-ratoon, and 8) secondary area under native vegetation, soil (LVE) with clay adopted as reference for comparison. Each area was georeferenced using GPS (Global Positioning System), delimitating three parts with one hectare for each one of the representative areas, distributed in a entirely casual outlining. There were two samples, one in September 2007, the dry period and the second in March 2008, the rainy season. Were collected 15 sub-samples of soil and root rhizospheric region at a depth of 0 to 30 cm, in order to obtain a composed sample. After being identified, the samples were put in polyethylene dark bags, stocked in aired place until further arrival at the phytopathology and Nematology Laboratory of the State University of Londrina- PR, where they were kept under refrigeration until their analysis. Were observed that the organic manure by the addition of vinasse and filter cake favors increasing the population of free-living nematodes. Moreover, the chemical fertilizer, especially in soils with medium texture, favors the population of Pratylenchus sp., and contributes to the largest populations of total fungi, total bacteria, phosphate solubilizing, actinomycetes. In secondary vegetation in native soil with clay, considered as reference area, were found the highest number of nematode of the genus Mesocriconema sp., And smaller populations of total fungi, cellulolytic, phosphate solubilizing and Paecilomyces sp. At population in different genera of nematodes in soil or in roots were higher in the sample of March 2008 (rainy season), while the count of microorganisms was significantly higher in the sample of October 2007 (dry period).