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El subproducto de la industria vitivinícola (SIV) es rico en compuestos bioactivos, incluidos los fenólicos. Dado que los nematodos del nudo de la raíz son suprimidos por compuestos fenólicos, la enmienda del suelo con SIV puede controlar estos patógenos. Evaluamos el efecto del subproducto de la industria vitivinícola (SIV) en el manejo de Meloidogyne javanica en plantas de tomate en invernadero. En el primer estudio, el suelo en macetas se enmendó con 0, 5, 10, 15, 20, 25 o 30 g de SIV por kg. Las dosis crecientes de SIV incrementaron el desarrollo de la planta. El SIV redujo la población de nematodos, especialmente a la dosis de 30 g kg-1 de suelo. En el segundo estudio, se diseñó un experimento de raíces divididas para evaluar si la enmienda del suelo con SIV (30 g kg-1 de suelo) induce resistencia en el tomate contra M. javanica. El SIV no induce resistencia en el tomate contra M. javanica. Este residuo controla el nematodo por contacto directo.

Few commercial genotypes of tomato are resistant to Fusarium wilt (Fusarium oxysporum f. sp. lycopersici [FOL]), especially to race 3. We developed five intraspecific hybrids of Solanum lycopersicum (FOX1 to FOX5) and assessed them for agronomic traits and resistance to FOL races 1, 2, 3, and a mixture of these races. FOX1 and FOX4 were resistant to all races and the race mixture but did not have the desired agronomic traits. Next, FOX1 and FOX4 were assessed as rootstocks of the cherry tomato Sweet Heaven. The grafting of Sweet Heaven on FOX4 did not reduce growth, gas exchange, yield, or fruit quality. When FOX1 was used as a rootstock, the fruits exhibited a reduction in firmness, fruit pulp pH, and total soluble solids by 14.3%, 1.2%, and 6.75%, respectively. Thus, the hybrid FOX4 can be used as a rootstock for Sweet Heaven to manage Fusarium wilt.

Anatomical, physiological, and biochemical analyses have been performed to predict graft compatibility. We analyzed if the concentrations of auxins, jasmonic acid, gibberellins, 1-aminocyclopropane-1-carboxylic acid, zeatin (cytokinin), salicylic acid, and abscisic acid could be used as predictors of compatibility between the rootstocks FOX1 and FOX4 (resistant to Fusarium wilt) and the scion of cherry tomatoes Sweet Heaven (SH). Self-grafted (SH/SH) and ungrafted SH plants (SH) were used as controls. Hormonal analyses were performed on leaves, at 20 and 70 days after grafting (DAG), and roots, at 20 DAG. No expressive concentrations of auxins, gibberellins, or jasmonic acid were detected. The concentrations of 1-aminocyclopropane-1-carboxylic acid, the immediate precursor of ethylene, and zeatin were altered at 20 DAG, but they stabilized at 70 DAG. Salicylic acid levels were reduced in the leaves of grafted plants at 70 DAG. The concentration of abscisic acid (ABA) in the leaves of SH grafted onto FOX1 was higher than in ungrafted and self-grafted plants at 70 DAG, suggesting some degree of incompatibility between these genotypes. The concentration of ABA in the combination FOX4/SH was similar to that in the self-grafted plants. Abscisic acid might be used as a reference phytohormone to predict graft compatibility among tomato genotypes.

Root-knot nematodes (RKN - Meloidogyne spp.) are one of the most serious threats to carrot production worldwide. In Brazil, carrots are grown throughout the year, and economic losses due to RKN are reported. Since little is known on the distribution of RKN species in carrot fields in Brazil, we collected plant and soil samples from 35 fields across six states. Based on the morphology of perineal patterns, esterase phenotypes and species-specific PCR, three Meloidogyne species were identified: 60% of the fields were infested with Meloidogyne incognita, M. javanica was reported in 42.9% of the areas, whereas M. hapla was detected in 17.1% of carrot fields. Mixed populations were reported in 20% of the areas with a predominance of M. incognita + M. javanica. The combination of morphological, biochemical, and molecular techniques is a useful approach to identify RKN species.

Quantitative polymerase chain reaction (qPCR) can be used for the accurate quantification of plant-parasitic nematodes from soil samples. Unlike the traditional Baermann funnel and centrifugal flotation techniques followed by visual enumeration, all developmental stages of plant-parasitic nematodes can be detected and quantified by using qPCR. However, little is known about the amount of DNA between different stages of plant-parasitic nematodes. Here, we show that ITS-copy number varies with developmental stage of Meloidogyne chitwoodi and M. hapla. The number of copies of ITS was lower in cell-stage eggs (51 ± 7.4 for M. hapla and 31 ± 6.0 for M. chitwoodi) than in second-stage juveniles (1345 ± 130.6 for M. hapla and 1036 ± 140.3 for M. chitwoodi) and females (19,508 ± 3367.3 for M. hapla and 9049 ± 316.7 for M. chitwoodi).

Alguns fungos sao agentes fitopatogenos nos diferentes varios estagios das culturas agricolas, tais como no plantio, na colheita, na pos-colheita e no armazenamento, podendo gerar grandes perdas economicas. A busca por produtos alternativos aos fungicidas sinteticos tem sido objeto de estudos visando obter novos compostos ativos com potencial controle das doencas. Neste sentido, os oleos essenciais mostram-se como alternativa potencial. A especie arborea Callistemom viminalis, de origem australiana, e comumente encontrada em territorio brasileiro, com porte de 3 a 7 metros de altura, com folhas pequenas, verdes, perenes e aromaticas, capaz de produzir grande quantidade de flores de coloracao vermelha e pequenos frutos, lenhosos e bem aderidos aos ramos. A Callistemom sp. e comumente empregada em silvicultura, paisagismo e na producao de oleo essencial. Neste trabalho, a acao fungicida do oleo essencial de C. viminalis foi avaliada sobre os fungos Aspergillus niger, Penicillium expansum e Cladosporium herbarium. O rendimento de extracao do oleo foi de 0,9 mL/100g de folhas frescas apos 1h de extracao. O oleo apresentou 12 componentes, sendo os principais: eucaliptol ou 1,8-cineol (74,1%), α-terpineol (11,0%) e α-pineno (9,2%), correspondendo a 94,3% da composicao total do oleo. Quando aplicado a uma concentracao de 0,2%, o oleo essencial apresentou atividade antifungica, inibindo o crescimento de P. expansum e C. herbarium. O ensaio de cromatografia em camada delgada-bioautografia indicou o eucaliptol e o α-terpineol como agentes ativos do oleo de C. viminalis, sendo o eucaliptol o agente inibidor para P. expansum e o α-terpineol como agente inibidor de C. herbarium.

One isolate of Colletotrichum truncatum was found recently causing severe anthracnose symptoms and leading to the death of beggartick (Bidens pilosa L. and Bidens subalternans DC.), one of the major weeds of Brazilian agriculture. This isolate, namely UFU 280, was selected for development of a mycoherbicide against this weed. Associated of beggartick, one of the, Here, results of a preliminary attempt to develop a protocol for mass production of inoculum (conidia) and fungal biomass of C. truncatum was performed aimed at paving the way for greenhouse and field evaluations of this biocontrol candidate. Isolates of Colletotrichum spp. have been successfully produced in the past to serve as the active ingredients of mycoherbicides. The method of choice has been the production of propagules through liquid fermentation. We assessed the effect of several options of liquid media recipes, type of seeding of medium, pH levels, incubation lengths, incubation temperatures and agitation speeds on the shaking speed on the concentration of conidia obtained per volume of medium. Additionally, a possible effect of the kind of medium utilized over the virulence of the inoculum was also evaluated through an inoculation study. We found that an adequate amount of conidia of C. truncatum (isolate - UFU 280) can be obtained in ME liquid culture medium, adjusted to a pH of 9.0, seeded with a conidial suspension and incubated for 6 days, under a regime of orbital shaking of 150 rpm, at temperatures ranging from 20 to 25 °C. Mortality of beggartick plants using conidia produced in different liquid culture media was of 100%.

Some essential oils are rich in nematicidal compounds and can be used for the management of plant-parasitic nematodes. Laboratory and field studies aiming to evaluate the efficiency of this compounds are necessary. The objective of this research was to assess the nematicidal potential of essential oils from leaves of Ageratum fastigiatum and Callistemon viminalis, and green and mature fruits of Schinus terebinthifolius on the root-knot nematode Meloidogyne javanica. In laboratory, the essential oil of S. terebinthifolius green fruits reduced hatching by more than 80% and increased juvenile mortality by 300% when compared to Tween 20 + water. In the field, none of the essential oils controlled M. javanica in lettuce. In conclusion, the essential oil of S. terebinthifolius green fruits reduces the egg hatching and kills J2 of M. javanica in laboratory. In an infested field with an average of 555 J2/100 cm3 of soil, the application of the essential oils of S. terebinthifolius, C. viminalis and A. fastigiatum does not control M. javanica in lettuce. Alguns óleos essenciais são ricos em compostos nematicidas e poderiam ser usados no manejo de fitonematoides. Estudos laboratoriais e de campo que visam avaliar a eficiência desses compostos são necessários. O objetivo desta pesquisa foi avaliar o potencial nematicida de óleos essenciais de folhas de Ageratum fastigiatum e Callistemon viminalis e frutos verdes e maduros de Schinus terebinthifolius sobre o nematoide de galhas Meloidogyne javanica. Em laboratório, o óleo essencial de frutos verdes de S. terebinthifolius reduziu mais de 80% a eclosão e aumentou em 300% a mortalidade de juvenis em comparação com Tween 20 + água. No campo, nenhum óleo essencial controlou M. javanica em alface. Em conclusão, o óleo de frutos verdes de S. terebinthifolius reduz a eclosão e mata J2 de M. javanica em laboratório. Em campo com infestação média de 555 J2/100 cm3 de solo, a aplicação dos óleos essenciaisde S. terebinthifolius, C. viminalis e A. fastigiatum não controla M. javanica em alface.&nbsp

Exposure of the nematophagous fungus Pochonia chlamydosporia to solar radiation and elevated temperatures before being incorporated into the soil can reduce its survival and efficiency as biocontrol agent. A field experiment was carried out to assess the effect of the exposure period on the viability of P. chlamydosporia applied on the soil surface. A commercial bionematicide based on P. chlamydosporia was sprayed on soil, and soil samples were collected before and at 0, 30, 60, 90, 120, and 150 min after fungal application. Relative humidity (RH), the irradiance (IR), air temperature (AT), and soil temperature (ST) were recorded. The number of P. chlamydosporia colony forming units (CFUs) was evaluated after 20 days of incubation. P. chlamydosporia survival decreased over the time of exposure on the soil surface. Overall, the number of CFUs decreased by more than 90% at 150 min after application. Exposure to RH ≥61%, ST and AT between 25–35 ◦ C and 19–29 ◦ C, and IR between 1172 and 2126 mol of photons m −2 s −1 induced a negative exponential effect on the survival of the fungus over the time. Exposure to climatic conditions on the soil surface reduces P. chlamydosporia viability. La exposición del hongo nematófago Pochonia chlamydosporia a la radiación solar y latemperatura elevada antes de ser incorporado al suelo puede reducir su supervivencia y eficiencia como agente de biocontrol. Se realizó un experimento de campo para evaluar el efecto del período de exposición a condiciones ambientales sobre la viabilidad de P. chlamydosporia en la superficie del suelo. Se pulverizó sobre el suelo un bionematicida comercial hecho a base de P. chlamydosporia y se recogieron muestras de suelo antes y después de 0, 30, 60, 90, 120 y 150 min tras la aplicación del hongo. Se registraron la humedad relativa (HR), la irradiación (IR), la temperatura del aire (TA) y la temperatura del suelo (TS). Se evaluó el número de unidades formadoras de colonias (UFC) de P. chlamydosporia después de 20 días de incubación. La supervivencia de P. chlamydosporia disminuyó durante el tiempo de exposición en la superficie del suelo. En general, el número de UFC disminuyó en más de un 90% a los 150 min después de la aplicación. La exposición a HR ≥ 61%, TS y TA entre 25-35 ◦ C y 19-29 ◦ C, e IR entre 1.172 y 2.126 mol de fotones m −2 s −1 indujo un efecto exponencial negativo en la supervivencia del hongo. La exposición a las condiciones climáticas en la superficie del suelo reduce la viabilidad de P. chlamydosporia.

The application of a bionematicide based on chlamydospores of Pochonia chlamydosporia (Pc-10) can be an important strategy for reducing the damage caused by Meloidogyne incognita on carrot. Based on this perspective, the nematicidal effects of 0, 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 kg ha-1 of Pc-10 were evaluated on carrot cv. Juliana under field conditions. Carrot yield and nematode population were influenced by increasing doses of Pc-10. The application of 3.0 kg ha-1 of Pc-10 increased the marketable production of carrot roots by 41.7% compared to the untreated control, whereas the production of unmarketable roots and the nematode population in the soil were reduced by 48.7% and 61.4%. The application of 3.0 kg ha-1 of Pc-10 reduces M. incognita population and improves carrot quality and yield. A aplicação de um bionematicida à base de clamidósporos de Pochonia chlamydosporia (Pc-10) pode se tornar uma importante estratégia para reduzir os danos causados por Meloidogyne incognita em cenoura. Baseado nessa perspectiva, o efeito nematicida de 0; 0,5; 1,0; 1,5; 2,0; 2.5 e 3,0 kg ha-1 de Pc-10 foi avaliado em área de produção de cenoura cv. Juliana em condições de campo. A produtividade de cenoura e a população do nematoide foram influenciados por doses crescentes de Pc-10. A aplicação de 3,0 kg ha-1 de Pc-10 aumentou a produção de raízes comerciais de cenoura em 41,7% comparada com aquela obtida na testemunha não tratada, enquanto que a produção de raízes não-comerciais e a população do nematoide no solo foram reduzidos em 48,7% e 61,4%, respectivamente. A aplicação de 3,0 kg ha-1 de Pc-10 reduz a população de M. incognita e aumenta a qualidade e a produtividade das raízes de cenoura.

The host status of eighteen progenies (CRP 01-12 to CRP 16-12, CRP 19-12 and CRP 20-12) and two cultivars (FB 200 Yellow Master and FB 300 Araguari) of yellow passion fruit to Meloidogyne incognita race 2 was evaluated in a greenhouse experiment. The height and the biomass of the plants, besides the numbers of galls, eggs and second-stage juveniles in roots and soil were assessed after 70 days of cultivation of the genotypes and tomato (control) in plastic pots with 2 kg of soil infested with 5,000 eggs of the nematode. The reproduction factor of the pathogen (RF = Final population/Initial population) was calculated for classifying the genotypes as immune (RF = 0), resistant (RF < 1) or susceptible (RF ≥ 1). The cultivar FB 200 is resistant to M. incognita race 2 and can be cultivated in areas infested with this nematode.

Eco-friendly approaches have been increasingly used for the management of plant-parasitic nematodes because of growing worldwide concern regarding health risks and environmental contamination caused by nematicides. Avoiding the introduction and spread of nematodes to non-infested areas is the most efficient method of control. Cleaning machinery and equipment, use of healthy planting materials, and quarantine procedures are good examples of preventive practices. In infested fields, nematode populations can be reduced by combining cultural, physical, and biological methods and genetic resistance of plants. The use of resistant crops is one of the most efficient and eco-friendly methods for reducing losses caused by plant-parasitic nematodes. Based on the information on which nematode species/races are prevalent in the field, the grower should choose a resistant crop, when available. Soil plowing and irrigation – named humid fallow – have been used for the management of root-knot nematodes in common bean (Phaseolus vulgaris), lettuce (Lactuca sativa), and okra (Abelmoschus esculentus) in Brazil. Soil steaming, treatment of planting materials with hot water, and soil solarization are recommended for the control of several plant-parasitic nematode species, based on the lethal action of high temperatures. Biofumigation with residues from some species of Brassicaceae and manures releases volatile toxic gases during the degradation process of the organic matter, including isothiocyanates. Non-host or antagonistic plants are also important tools for the integrated management of nematodes. In this context, marigolds (Tagetes erecta and T. patula), crotalaria (Crotalaria spectabilis), sunn hemp (Crotalaria juncea), and velvet bean (Mucuna pruriens) are widely used as antagonistic plants. Soil amendment with crop residues of neem (Azadirachta indica), castor bean (Ricinus communis), velvet bean (Mucuna pruriens), crotalaria (Crotalaria spectabilis), and Brassica spp.; oil seed cakes of neem, castor bean, mustard, and sesame; cattle manure; poultry litter; liquid swine manure; and crab shells release nematotoxic substances during decomposition, provide nutrients to the plants, and increase the population of biocontrol agents. More than 200 species of nematode antagonists have been identified, including fungi, bacteria, nematodes, tardigrades, and collemboles. Fungi and bacteria are the most studied and commercially exploited organisms for nematode control. Several commercial bionematicides have been developed from the nematode-trapping fungi Arthrobotrys, Dactylaria, Dactylella, and Monacrosporium, the egg-parasitic fungi Purpureocillium lilacinum and Pochonia chlamydosporia, the antibiotic bacterium Bacillus species, and the obligate parasite bacterium Pasteuria spp. The anaerobic soil disinfestation is an ecological alternative to soil fumigation for the control of several soilborne pathogens, including nematodes. This technique consists of incorporating organic material that is easily decomposable (C/N ratio from 8 to 20:1) into the soil, irrigating to saturation, and covering the soil with oxygen-impermeable plastic. Accumulation of toxic products from anaerobic decomposition, antagonism by anaerobic organisms, lack of oxygen, and the combination of all of them are the main drivers that explain the efficacy of anaerobic soil disinfestation. Consumers have been demanding higher food security and environmental quality, and this situation will not be different in the future. In this context, scientists’ efforts in discovering new nonchemical strategies for nematode control and improvements in the current methods must be continuous.

Pochonia chlamydosporia is one of the most studied biological control agents of plant-parasitic nematodes. Soil amendment with agro-industrial residues may also suppress nematodes and improve plant growth. Therefore, the combined application of P. chlamydosporia and organic residues may enhance the control of nematodes. This study was designed to evaluate whether the integrated use of Pochonia chlamydosporia and the solid by-product of the wine industry (SBWI) controls Meloidogyne javanica. In greenhouse trials, SBWI (30 g kg−1 of air-dry soil) was applied to the soil with chlamydospores (500; 1500; 2500; 3500; 4500 and 5000 chlamydospores g-1 of air-dry soil) or colonised rice grains with mycelia and conidia of P. chlamydosporia (2.5; 5; 10 and 15 g kg-1 of air-dry soil). In laboratory, we assessed the effect of SBWI on the development of P. chlamydosporia. SBWI reduced the mycelial growth and sporulation of P. chlamydosporia in vitro. However, the integrated use of SBWI with the fungus increased tomato growth and reduced the number of galls and eggs of M. javanica per gram of tomato root in the greenhouse conditions, mainly when the fungus was applied at a rate of 3500 chlamydospores g-1 of soil and 15 g of colonised rice kg-1 of soil. In conclusion, the integrated use of P. chlamydosporia and SBWI controls M. javanica.

Essential oils and plant extracts contain a multitude of bioactive substances against fungi, bacteria and nematodes. In plant pathology research, botanicals are commonly used in their raw state. Without any type of formulation, bioactive compounds of plants can be degraded and volatilized rapidly under field conditions. Controlled-release liquid and solid formulations with plant compounds as active ingredients are common in some fields, such as medicine, pharmaceuticals, food technology and cosmetology. However, the use of controlled-release formulations is an under explored approach in plant pathology, although these technologies are interesting options for managing seed, soil-borne and post-harvest pathogens. In this review, we discuss the potential and options of formulations of botanicals against plant pathogens.

Neste estudo avaliou-se o efeito do extrato aquoso do subproduto da industria vinicola (SIV) sobre a eclosao e mortalidade de juvenis de segundo estadio (J2 ) de Meloidogyne javanica , e o efeito do SIV incorporado ao solo sobre a eclosao e viabilidade dos J2 no solo. O extrato aquoso do SIV reduziu a eclosao e matou os J2 de M. javanica e, quando incorporado ao solo, o residuo orgânico reduziu a eclosao e viabilidade dos J2 do nematode. Acido galico, acido cafeico, acido ferulico, acido p -cumarico e trans -resveratrol foram os compostos fenolicos identificados no extrato aquoso do SIV por cromatografia liquida de alta eficiencia (HPLC). O subproduto da industria vinicola possui acao nematicida contra M. javanica e e possivel que a aplicacao desse residuo no solo possa ser uma estrategia adicional para o controlo do patogenio.

The application of the nematophagous fungus Pochonia chlamydosporia var. chlamydosporia (Goddard) Zare & W. Gams during seedling production of vegetable crops can be an efficient approach to control root-knot nematode. The aim of this study was to evaluate the effect of treating seedlings and/or soil with bionematicide (wettable powder formulation) based on chlamydospores from isolate Pc-10 on the Meloidogyne javanica (Treub, 1885) control in lettuce (Lactuca sativa L.). Isolate Pc-10 was diluted in water and applied when watering the seedlings (0, 4.5, 9.0, 13.5, and 18.0 g L -1 ) and/or to the potted soil (5000 chlamydospores g -1 ) used for growing lettuce. The soil in each pot was infested with 3000 M. javanica eggs. The number of M. javanica eggs was reduced in lettuce roots when isolate Pc-10 was applied either to seedlings or soil; there was no interaction between application methods. The decrease in the number of eggs was proportional to the increase of isolate Pc-10 applied to seedlings with maximum reduction of 43.5% at the 18 g L -1 dose. When the fungus was applied to the soil, the number of eggs was reduced by 12.3%. Increasing doses of isolate Pc-10 reduced the number of galls up to 21% with the 18 g L -1 dose. Applying bionematicide based on P. chlamydosporia isolate Pc-10 at 18 g L -1 on seedlings controls M. javanica in lettuce.

espanolBacterias del genero Bacillus pueden suprimirpoblaciones de nematodosfitoparasitos. Sobre la base de esta hipotesis, ocho cepas de Bacillus (SF262, SF264, SF266, SF267, SF268, SF271, SF292 y SF 629)fueronformuladas y aplicadas en el tratamiento de semillas y en la superficie de suelo para el control de Pratylenchus brachyurus en frijol. La aplicacion de las cepas no aumentaron la produccion de granos y la masa de las raices, ni redujeron el numero de nematodos en el suelo y en las raices. Asi, ninguna de las cepas de Bacillus es promisoria para el control del nematodo lesionador en frijol. EnglishBacteria belonging to the genus Bacillus can promote plant growth and suppress plant-parasitic nematode populations. Based on this hypothesis, eight strains of the bacterium (SF 262, SF 264, SF 266, SF 267, SF 268, SF 271, SF 292 and SF 629) were formulated and applied as a seed treatment and/or sprayed on the soil surface with the aim of controlling Pratylenchys brachyurus in common bean under field conditions. The application of the bacterial isolates neither improved the grain yield and the root mass nor reduced the number of nematodes in the soil and in the roots of common bean. Thus none of the isolates of Bacillus spp. evaluated in this work are promising for the control of the lesion nematode on common bean.

Three different isolates of Pochonia chlamydosporia (Pc-3, Pc-10 and Pc-28) were evaluated in a greenhouse experiment when applied individually and in combinations. A control treatment with no application of isolates of P. chlamydosporia var. chlamydosporia was included, while neither isolates nor nematodes were used in another untreated treatment. One-liter pots were filled with sterilized soil, and each pot was infested with 3 g of rice substrate colonized with the respective isolate plus 3,000 eggs of Meloidogyne javanica. One 'Santa Clara' tomato seedling was transplanted to each pot after fifteen days. None of the isolates (applied individually or in combinations) was able to reduce the number of galls when compared to the control treatment. However, the number of eggs of M. javanica decreased for isolates Pc-10 and mixtures Pc-10 + Pc-3, and Pc-10 + Pc-28 + Pc-3. The association of isolates of P. chlamydosporia var. chlamydosporia did not increase the control of M. javanica when compared to the application of Pc-10 individually.

The fungus Pochonia chlamydosporia var. chlamydosporia isolate Pc-10 (Pc-10) presents great potential for the management of root-knot nematodes on vegetable crops. However, there is no information about the use of Pc-10 on carrot. Thus, we evaluated in this study the effect of Pc-10 incorporated into the soil (PCI) or applied to the surface of the beds (PCS) on control of Meloidogyne incognita on carrot under field conditions, in comparison to an untreated control and the bionematicides Paecilomyces lilacinus + Bacillus subtilis (PLBS), mix of nematophagous fungi and Bacillus sp. (NFB) and P. lilacinus (PL). PCI increased the total and marketable production of carrot roots by 25.35 and 55.03 %, respectively. The production of unmarketable roots was reduced by about 50 % in plots treated with PCI, PCS and PLBS. All bionematicides reduced the number of unmarketable roots with galls, but only PCI reduced the reproduction factor of the nematode. The incorporation of Pc-10 in the soil of the beds controls M. incognita and improves carrot quality and yield.

This study was done to evaluate the effect of the bionematicide Pc-10, based on Pochonia chlamydosporia var. chlamydosporia, on the control of Meloidogyne javanica. The fungus was applied by two methods: (1) drenching the substrate of seedlings with an aqueous suspension of Pc-10 (0, 4.5, 9.0, 13.5 and 18.0 g/L), or (2) incorporating Pc-10 into the soil of potted plants at a rate of 5000 chlamydospores/g of soil. The soil of each pot was infested with 3000 eggs of M. javanica, and one cucumber seedling was transplanted to each pot after 1 week. Increasing the doses of Pc-10 in the seedlings reduced the numbers of galls/g and eggs/g in the roots of cucumber plants in both experiments, regardless of the application method of the fungus in the soil. The application of 18 g/L of Pc-10 in the seedlings reduced the number of galls/g of roots by 46.04% and 49.44%, and the number of eggs/g of roots by 48.32% and 40.58% in the first and second experiments, respectively. Soil application of Pc-10 reduced the number of eggs/g of roots by 19.42% in the first experiment only. Drenching the substrate of seedlings with Pc-10 at 18 g/L controls M. javanica in cucumber and does not require additional fungus application in the soil.

Pochonia parasitizes the eggs and females of plant-parasitic nematodes (PPN). The fungus-nematode interaction involves a complex series of events which can be affected by the environment. Thus, an understanding of the bionomics of this interaction is essential in order to improve the efficiency of the biological management of PPN. In this chapter, we provide an overview of the process of infection of nematodes by Pochonia and the role of the environment on the fungus-nematode interaction. Firstly, we focus on the events and the mechanisms underlying adhesion, penetration and colonisation of nematodes by Pochonia. We discuss how the infection process is driven by both mechanical forces, induced by the appressoria, and enzymatic activity, specifically by the serine proteases (P32, VCP1, SCP1) and chitinases. Environmental factors have a profound influence on the Pochonia-nematode interaction and these are discussed in detail. Temperature, pH, soil type, soil microbiota and roots can enhance or reduce the parasitism of the nematode by the fungal antagonist. Finally, we discuss how the method of application of Pochonia and its timing can impact on the establishment of the fungus in the soil and, consequently, on the control of nematodes.

Screening passion fruit genotypes to target resistance to scab and bacterial blight may play an important role in reducing the application of chemical products and losses caused by the diseases. It is likely that resistant genotypes may be found in ongoing breeding programs targeting production traits. Thus, the objective of this work was to evaluate the host status of eighteen passion fruit genotypes from the Breeding Program of the Universidade Federal de Viçosa (CRP 01-12 to CRP 16-12, CRP 19-12 and CRP 20-12) and two cultivars (FB 200 Yellow Master and FB 300 Araguari) of yellow passion fruit to the scab (Cladosporium herbarum) and bacterial blight (Xanthomonas axonopodis pv. passiflorae). The fungus and the bacterium were artificially inoculated on wounded leaves at the concentrations of 1 x 106 spores mL-1 and 1 x 108 cfu mL-1. Scab incidence and severity were assessed at 7, 14, 21 and 31 days after inoculation (DAI); whereas the bacterial blight evaluations were performed at 10, 20, 28 and 44 DAI. The genotypes CRP 01-12 to CRP 16-12 and CRP 19-12 are moderately resistant to scab. The genotype 20-12 and the FB 200 Yellow Master cultivar are susceptible to the fungus. All genotypes are highly susceptible to bacterial blight. A seleção de genótipos de maracujazeiro visando resistência à verrugose e bacteriose pode ter importante papel na redução da aplicação de produtos químicos e perdas causadas por essas doenças. É provável que genótipos resistentes possam ser encontrados em programas de melhoramento visando seleção de caracteres relacionados à produção. Assim, o objetivo deste trabalho foi avaliar a hospedabilidade de dezoito genótipos de maracujazeiro amarelo provenientes do Programa de Melhoramento Genético da Universidade Federal de Viçosa (CRP 01-12 a CRP 16-12, CRP 19-12 e CRP 20-12) e dois cultivares comerciais (FB 200 Yellow Master e FB 300 Araguari) à verrugose (causada por Cladosporium herbarum) e bacteriose (Xanthomonas axonopodis pv. passiflorae). O fungo e a bactéria foram inoculados em folhas com ferimentos nas concentrações de 1 x 106 esporos mL-1 e 1 x 108 ufc mL-1. A incidência e a severidade de verrugose foram avaliadas aos 7, 14, 21 e 31 dias após a inoculação (DAI); enquanto que as avaliações da bacteriose foram aos 10, 20, 28 e 44 DAI. Os genótipos CRP 01-12 a CRP 16-12 e CRP 19-12 são moderamente resistentes à verrugose. O genótipo CRP 20-12 e o cultivar FB 200 Yellow Master são suscetíveis ao fungo. Todos os genótipos são altamente suscetíveis à bacteriose.

Pochonia species can occur in many Meloidogyne- infested soils throughout the world. The objective of this work was to isolate Pochonia species from different Meloidogyne- infested soil locations in Brazil and to screen for potential isolates effective in controlling Meloidogyne javanica under glasshouse conditions. A total of 29 isolates were identified as Pochonia chlamydosporia . Among them, 65.52% were identified as P. chlamydosporia var. chlamydosporia and 34.48% as P. chlamydosporia var. catenulata. For the glasshouse experiments, fungal chlamydospores were incorporated into the soil (5000 g soil −1 ) and one tomato seedling was transplanted in 300 mL pot. After one week, each plant was inoculated with 1000 eggs of M. javanica. The isolates 1, 2, 3, 4, 9, 10, 21, 24, 28 (from Brazil) and 64 (from Spain) were the most efficient in reducing the number of eggs of the nematode. These isolates were re-evaluated in another glasshouse experiment, this time the number of eggs was increased (3000), inoculating both eggs and chlamydospores at the same time. After one week of inoculation, a tomato seedling was transplanted in each pot. In this experiment, isolates 64 and 10 were the most efficient in reducing the number of eggs by 72% and 60%, respectively.

O objetivo deste trabalho foi avaliar a eficiencia de fungicidas no controle das doencas foliares do milho provocadas por Phaeosphaeria maydis e Puccinia polysora e na produtividade da cultura . O experimento foi realizado na Fazenda Vinicius, localizada no municipio de Patos de Minas - MG. Os seguintes fungicidas (g.i.ha -1 ) foram aplicados na cultivar 30F53H, com pulverizador costal/manual, no estadio fenologico de V10 (dez folhas completamente desenvolvidas) da cultura: piraclostrobina + epoxiconazol (133 + 50), azoxistrobina + ciproconazol (200 + 80), trifloxistrobina + tebuconazol (100 + 200). O delineamento experimental utilizado foi o de blocos ao acaso com quatro tratamentos e quatro repeticoes. Parcelas sem fungicidas constituiram a testemunha. Para a avaliacao sintomatologica, utilizou-se escalas de notas de severidade de 0 a 5 (0= ausencia de lesoes ou pustulas foliares e 5= lesoes em 100% das folhas, com seca das plantas). Houve reducao significativa da severidade da mancha de Phaeosphaeria maydis em parcelas onde foram aplicados os fungicidas em relacao a testemunha , porem nao houve diferenca entre os fungicidas testados. Nao houve diferenca significativa entre os tratamentos no controle de Puccinia polysora e na produtividade da cultura do milho.

Greenhouse experiments were conducted to evaluate the effect of soil amendment with chopped (1cm²) or ground (1mm sieve) dry leaves of assa-peixe (Vernonia polyanthes), lemon-grass (Cymbopogon citratus), eucalyptus (Eucalyptus citriodora), castor (Ricinus communis), mango (Mangifera indica) or neem (Azadirachta indica) for the control Meloidogyne javanica. Into the soil (Yellow red oxisol) of each pot were added leaves (5g kg-1 of soil) and 5,000 eggs of the nematode. After seven days, one tomato seedling "Santa Cruz Kada" was transplanted to each pot. The tomato root weight, galls and eggs/root system were determined 60 days after transplant. None of the soil amendments reduced gall or eggs, when applied as leaf pieces. However, all tested plant species reduced the gall number, when they were incorporated into the soil as powder, and maximum nematode suppression occurred in soil amended with neem leaves (61%). The amendment with ground leaves of castor, neem, eucalyptus and lemon-grass reduced the number of eggs, with maximum reduction occurring in soil amended with ground castor leaves (69%), evidencing that these organic amendments can be an alternative for M. javanica control in tomato. Further studies are required under field conditions to confirm the potential of these organic amendments on the control of M. javanica. Experimentos em casa de vegetação foram conduzidos com o objetivo de avaliar o efeito da adição ao solo de folhas secas picadas (1cm²) ou trituradas (peneira de 1mm) de assa-peixe (Vernonia polyanthes), capim-limão (Cymbopogon citratus), eucalipto (Eucalyptus citriodora), mamona (Ricinus communis), manga (Mangifera indica) ou nim (Azadirachta indica) para o controle de Meloidogyne javanica. Ao solo de cada vaso (latossolo vermelho-amarelo), foram adicionadas folhas (5g kg-1 de solo) e 5.000 ovos do nematoide. Após sete dias, uma muda de tomateiro "Santa Cruz Kada" foi transplantada em cada vaso. O peso das raízes e os números de galhas e de ovos foram avaliados 60 dias após o transplantio. As folhas picadas de nenhuma planta reduziram o número de galhas e de ovos. Entretanto, as folhas de todas as plantas estudadas reduziram o número de galhas quando foram incorporadas ao solo na forma de pó e a máxima supressão foi obtida com as folhas de nim (61%). A adição ao solo de folhas trituradas de mamona, nim, eucalipto e capim-cidreira reduziu o número de ovos, com redução máxima após aplicação de folhas de mamona (69%), indicando que esses materiais orgânicos podem ser uma alternativa de controle de M. javanica em tomateiro. Novos estudos devem ser realizados em condições de campo para confirmar o potencial desses materiais orgânicos no controle de M. javanica.

{null=The objective of this research was to evaluate the effect of the combination of Pochonia chlamydosporia var. chlamydosporia with summer and winter cover plants on the control of Meloidogyne javanica on tomato plants under glasshouse conditions. Treatment combinations were with four soil covers (pearl millet and Surinam grass in Experiment 1, oil radish and black oat in Experiment 2; plus tomato and fallow controls) and two P. chlamydosporia treatments (with or without the fungus). The antagonist was applied to nematode-infested soil when the cover crops or tomato were planted. Tomato plants were removed and the above-ground parts of the cover crops were cut, dried, and placed on the pots 60 days after planting. One tomato seedling was transplanted in each pot in a no-tillage system and cultivated for 60 days. Surinam grass, pearl millet and black oat reduced galls and eggs of M. javanica by more than 90%, without application of the fungus. However, P. chlamydosporia + Surinam grass significantly reduced by 72% the number of galls compared with cultivation of the grass in soil without the fungus. Pochonia chlamydosporia became established in soil and could be re-isolated at the end of both experiments. Colony forming units (CFU) (g soil)–1 varied from 1.0 × 105 (fallow) to 2.6 × 105 (pearl millet) and from 1.1 × 105 (fallow) to 2.3 × 105 (oil radish) for the experiments with summer soil cover crops and winter soil cover crops, respectively. The cultivation of Surinam grass, pearl millet and black oat reduced M. javanica populations, and the combination with P. chlamydosporia may favour the establishment of the fungus in the soil and enhance the control of the nematode., en= The objective of this research was to evaluate the effect of the combination of Pochonia chlamydosporia var. chlamydosporia with summer and winter cover plants on the control of Meloidogyne javanica on tomato plants under glasshouse conditions. Treatment combinations were with four soil covers (pearl millet and Surinam grass in Experiment 1, oil radish and black oat in Experiment 2; plus tomato and fallow controls) and two P. chlamydosporia treatments (with or without the fungus). The antagonist was applied to nematode-infested soil when the cover crops or tomato were planted. Tomato plants were removed and the above-ground parts of the cover crops were cut, dried, and placed on the pots 60 days after planting. One tomato seedling was transplanted in each pot in a no-tillage system and cultivated for 60 days. Surinam grass, pearl millet and black oat reduced galls and eggs of M. javanica by more than 90%, without application of the fungus. However, P. chlamydosporia+Surinam grass significantly reduced by 72% the number of galls compared with cultivation of the grass in soil without the fungus. Pochonia chlamydosporia became established in soil and could be re-isolated at the end of both experiments. Colony forming units (CFU) (g soil)−1 varied from 1.0×105 (fallow) to 2.6×105 (pearl millet) and from 1.1×105 (fallow) to 2.3×105 (oil radish) for the experiments with summer soil cover crops and winter soil cover crops, respectively. The cultivation of Surinam grass, pearl millet and black oat reduced M. javanica populations, and the combination with P. chlamydosporia may favour the establishment of the fungus in the soil and enhance the control of the nematode. }

The objective of this work was to evaluate the effect of Bacillus spp. isolates on the control of Meloidogyne incognita in greenhouse and field experiments. In the greenhouse, isolates 57 ( Bacillus sp.), 63 ( Bacillus amyloliquefaciens ), SF 194 ( Bacillus sp.), SF 203 ( Bacillus amyloliquefaciens ), and a mixture containing the four isolates were applied to the soil surface (2 L ha -1 , 1×10 9 cfu mL -1 ), infested with 5,000 eggs of M. incognita . Sixty days after planting, the mass of the bean roots and the number of galls and eggs were evaluated. In a field natu­rally infested with M. incognita , the effects of isolates 57, 63, and a mixture containing both of them were observed after application to the soil surface (2 L ha -1 ), with or without seed treatment with the isolates (2 mL kg -1 ). Produc­tion, thousand-grain weight, reproductive factor, and number of eggs were evaluated at 90 days after planting. In the greenhouse, the application of the isolates did not influence neither root biomass, nor the number of galls and eggs. In the field, the application of isolates 57, 63, and the mixture 57 + 63 on the soil surface and in seed treat­ment did not increase total production and thousand-grain weight, nor did it reduce the nematode multiplication in the soil and in the roots of the plants. Thus, Bacillus spp. isolates 57, 63, SF 194, and SF 203 have no potential to formulate bionematicides for the control of M. incognita in common bean.

Stromatinia cepivora (= Sclerotium cepivorum ), causal agent of the white rot, is a major soilborne pathogen that attacks garlic ( Allium sativum L.), onion ( Allium cepa L.), and other plants of the Alliacea family. The pathogen is difficult to control because it survives as sclerotia for decades in soil. White rot can cause total crop losses when sclerotia levels are high in soil and environmental conditions favorable for disease development. Aspects of the biology and epidemiology of S . cepivora have been investigated extensively worldwide. These studies have pro­vided essential information to develop different control strategies. Currently, white rot management is based pri­marily on the application of fungicides and biocontrol agents to protect the crop against infection, and the use of natural and synthetic germination stimulants of sclerotia, soil fumigation and solarization to reduce sclerotia den­sity in soils. In Brazil, few studies have been conducted to understand white rot epidemiology and effectiveness of control measures currently available, despite the disease being an economically important in garlic and onion production regions for many years. This review provides updated information on the biology of S. cepivora , and epidemiology and control of white rot to identify important knowledge gaps and future research directions for white rot in Brazil.

Stromatinia cepivora is one of the major pathogens of Allium species worldwide. Assuming that substances pro­duced by plants may be used in the management of this pathogen, the effect of plant extracts and essential oils on the mycelial growth and germination of S. cepivora was assessed in this study. The fungus was grown on PDA medium with aqueous and ethanolic extracts (20 %, m:v) of mentrasto, rue, ginger, false saffron, garlic and citron­ella at the concentrations of 1 or 10 mL L -1 and the essential oils of citronella, rosemary, neem and Corymbia citriodora at 100, 200, 400, 800 or 1,200 µL L -1 . None of the plant extracts reduced the germination of the sclerotia. All aqueous extracts at 10,000 µL L -1 reduced the growth of the fungus from 28.0% to 53.5%. At the 1,000 µL L -1 , the ethanolic extracts of ginger, citronella, rue and false saffron reduced the mycelial growth of the pathogen up to 45.1 %, especially the extract of ginger. The essential oils of all the plants suppressed the mycelial growth of S. cepivora at 800 and 1,200 µL L -1 , especially the citronella and rosemary oils at 1,200 µL L -1 , which caused 100% of inhibition. 5 % of sclerotia germinated in PDA containing the oils at 1,200 µL L -1 , regardless the plants. The extracts of mentrasto, rue, ginger, false saffron and citronella and especially the essential oils of cit­ronella, rosemary, neem and C. citriodora at 1,200 µL L -1 have substances that inhibit the growth of S . cepivora .