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Trichoderma is the most studied and used fungal agent in biological disease control worldwide. Its prospection is a necessary routine, in order to select more effective and specific strains for the different existing agro pathosystems. This work reports the in vitro antagonism (Mycelial Growth Inhibition - MGI) of five Trichoderma isolates, obtained from rhizospheric and organic soil of medicinal plants cultivated in Brazil, to five different phytopathogenic fungi and their molecular identification based on actin (act), calmaldulin (cal), rDNA gene (ITS) and translation elongation factor 1-α (tef1-α). Regarding the fungus Macrophomina phaseolina, the MGI varied between 63.33 and 67.03%; for Fusarium verticillioides between 67.20 and 85.92%; Phaeocytostroma sacchari between 84.00 and 92.90%; in the case of Sclerotinia sclerotiorum, the inhibition was total (100%), and for Sclerotium rolfsii, the antagonism was between 62.03 and 79.07%. According to the molecular phylogeny performed, concatenated analysis of the genetic markers revealed that the five antagonist fungi belong to the Trichoderma afroharzianum species. It is concluded that the T. afroharzianum isolates evaluated showed good levels of in vitro control of the plant pathogenic fungi in question and will be studied via in vivo tests and in plant growth promotion.

The target leaf spot, an end-of-cycle disease that can cause soybean losses of 40%, is caused by the fungus Corynespora cassiicola. The aim of this study was to devise and validate a multiplex PCR protocol for the molecular identification of C. cassiicola, in both pure cultures of isolates and plants. For the analysis, a total of 75 samples was evaluated been 57 possible fungal isolates of C. cassiicola and 18 soybean plants displaying symptoms associated with target leaf spot. Total DNA was extracted from the pure cultures of the isolates and of four symptomatic leaf discs taken from each of the plants soybean evaluated and submitted to the conventional multiplex PCR technique using two primer pairs: ITS-1/ITS-4 and GA4-F/GA4-R. The ideal conditions for multiplex PCR were adjusted. The 57 isolates identified as C. cassiicola and among the evaluated plants, 15 samples were infected. Conventional multiplex PCR is efficient at identifying Corynespora cassiicola isolates and for rapid diagnosis of infected plants.

The constant demand by society for quality timber associated with reduced exploitation of native forests has promoted the use of alternative species such as the African Mahogany (Khaya grandifoliola C. Dc.). The production cycle of this species began with the introduction of seeds in the 1970s and good silvicultural performance of the first planted matrix trees, then spreading throughout several Brazilian regions and resulting in increased occurrence of pest insects and diseases, such as African mahogany canker (Lasiodiplodia theobromae Pat.). In this context, this work aimed to identify control methods and to analyze the damage caused by canker in symptomatic African mahogany trees. Scraping and chemical treatments were carried out in different concentrations to analyze the best method to prevent an increase of lesions caused by the pathogen. The anatomical characteristics and basic density of wood with and without canker were evaluated. It was observed that scraping until reaching the healthy tissue is an effective method of control which stimulates the healing process after a certain period. For the chemical treatment without scraping, Nativo® fungicide is efficient through direct application. The presence of canker promoted an increase in wood density and changes in anatomical characteristics.

Common bean is an economically important crop grown in several areas in the world. Among the constraints for this crop development, bean rugose mosaic virus (BRMV) infections can potentially lead to serious yield reduction. Genetic resistance is the most effective control method, and the search for sources of resistance is an essential step. The objective of this study was to biologically characterize the BRMVGO isolate and search for virus resistance in germplasm accessions of Phaseolus vulgaris L. To biologically characterize the isolate, 15 plants, selected from a list of indicators, were inoculated, among them soybean (Glycine max L) and pea (Pisum sativum L). The host range demonstrated that the virus can infect different plant species, reinforcing the need for resistance sources. In order to screen for resistance, 172 P. vulgaris accessions were inoculated with the isolate and scored for disease symptoms at 5, 21 and 30 days after inoculation. Among the evaluated accessions, four exhibited hypersensitive reactions (HR) while the remaining showed typical susceptible reactions. The virus seemed to be restricted and could not be retrieved from the common bean accessions showing HR and they are likely interesting sources of resistance for use in breeding programs.

Simple Summary Invasive species are a constant threat to agriculture throughout the world against which early detection is one of the primary defenses. The Old World bollworm is one of the most important invasive agricultural pests in the world. While historically absent from the Americas, this species was first found in South America in 2013 and poses an ongoing threat of spreading into North America. Surveys are conducted each year, which result in hundreds or thousands of traps that must be screened for this species. Unfortunately, the most common non-target is the native corn earworm, which is nearly identical morphologically to the Old World bollworm and cannot be easily separated. Molecular methods have been developed to screen these trap samples, but the required equipment is expensive and not commonly available. This study details improvements to current molecular methods that will allow for screening of bulk trap samples using standard laboratory instruments and protocols. The ability to perform these methods in nearly any molecular biology lab will greatly enhance our ability to detect and exclude this important pest. Abstract Helicoverpa armigera (Hübner) is one of the most important agricultural pests in the world. This historically Old World species was first reported in Brazil in 2013 and has since spread throughout much of South America and into the Caribbean. Throughout North America, H. armigera surveys are ongoing to detect any incursions. Each trap is capable of capturing hundreds of native Helicoverpa zea (Boddie). The two species cannot be separated without genitalic dissection or molecular methods. A ddPCR assay is currently used to screen large trap samples, but this equipment is relatively uncommon and expensive. Here, we optimized a newly designed assay for accurate and repeatable detection of H. armigera in bulk samples across both ddPCR and less costly, and more common, real-time PCR methods. Improvements over previously designed assays were sought through multiple means. Our results suggest bulk real-time PCR assays can be improved through changes in DNA extraction and purification, so that real-time PCR can be substituted for ddPCR in screening projects. While ddPCR remains a more sensitive method for detection of H. armigera in bulk samples, the improvements in assay design, DNA extraction, and purification presented here also enhance assay performance over previous protocols.

Some microbial volatile organic compounds (mVOCs) can be toxic to phytopathogens, but information about their in vivo effect and the contribution of individual mVOC to biocontrol is scarce. In this study, we evaluated the in vitro and in vivo effect of Bacillus amylolicefaciens ALB629 and UFLA285 mVOCs on anthracnose (Colletotrichum lindemuthianum) control in common bean (Phaseolus vulgaris L.). ALB629 reduced C. lindemuthianum spore numbers (31%), while UFLA285 and ALB629 inhibited mycelial growth by 16 and 18%, respectively. Both bacterial volatiles controlled anthracnose in vivo (79–85%). The volatiles from UFLA285 and ALB629, identified as 3-methylbutanoic acid and 2-methylbutanoic acid, were toxic to the pathogen when applied individually or in combination, likely being the ones that play a role in common bean protection against anthracnose. Bacterial-VOCs 3-methylbutanoic acid and/or 2-methylbutanoic acid could be used to protect common bean against anthracnose.

Agriculture accounts for ~ 70% of all water use and the world population is increasing annually; soon more people will need to be fed, while also using less water. The use of plant-associated bacteria (PAB) is an eco-friendly alternative that can increase crop water use efficiency. This work aimed to study the effect of some PAB on increasing soybean tolerance to drought stress, the mechanisms of the drought tolerance process, and the effect of the PAB on promoting plant growth and on the biocontrol of Sclerotinia sclerotiorum. PAB were isolated from soybean rhizosphere and S. sclerotiorum sclerotia. The strains identified as UFGS1 (Bacillus subtilis), UFGS2 (Bacillus thuringiensis), UFGRB2 and UFGRB3 (Bacillus cereus) were selected on their ability to grow in media with reduced water activity. Soybean plants were inoculated with the PAB and evaluated for growth promotion, physiological and molecular parameters, after drought stress. Under drought stress, UFGS2 and UFGRB2 sustained potential quantum efficiency of PSII (Fv/Fm), while a decrease was found in the control plants. Moreover, UFGS2 and UFGRB3 maintained the photosynthetic rates in non-stressed conditions compared to the control. UFGS2-treated plants showed a higher stomatal conductance and higher transpiration than the control, after drought stress. Some PAB-treated plants also had other beneficial phenotypes, such as increases in fresh and dried biomass relative to the control. Differential gene expression analysis of genes involved in plant stress pathways shows changes in expression in PAB-treated plants. Results from this study suggest that PAB can mitigate drought stress in soybean and may improve water efficiency under certain conditions.

Soybean target spot (Corynespora cassiicola) has become an important disease in most soybean growing regions in Brazil. The sensitivity of 34 isolates of C. cassiicola to 11 fungicides was evaluated based on mycelial growth inhibition (boscalid, carbendazim, cyproconazole, fluopyram, fluxapyroxad, prothioconazole and thiophanate-methyl) or spore germination inhibition (azoxystrobin, picoxystrobin, pyraclostrobin and trifloxystrobin). In addition, the efficacy of five fungicides to control target spot was tested in four field trials carried out during three crop seasons: 2011/2012, 2012/2013 and 2013/2014. Fungal isolates were collected from soybean plants in several soybean growing areas in Brazil. The effective concentration of each fungicide to inhibit fungal growth or spore germination by 50% (EC50) was calculated for all isolates. Fluxapyroxad and prothioconazole provided the greatest mycelial growth inhibition and pyraclostrobin led to the lowest spore germination percentage, with the lowest EC50 values. At field experiments, cyproconazole and carbendazim showed target spot control ranging from 26% to 29%. On the other hand, fluxapyroxad and prothioconazole prevented an epidemic of the disease by 45% to 55%, respectively. In general, the efficacy of fungicides in the field reflected the in vitro sensitivity averages. Large sensitivity reduction was detected to benzimidazoles (MBC), indicating that this group of fungicides should no longer be used for target spot control. There was a negative and significant correlation (-0.265) between target spot severity and soybean yield. The pathogen showed variability in sensitivity to the fungicide groups carboxamides (SDHI), triazoles (DMI) and strobilurins (QoI), which denotes a high risk of selection for resistance.

The use of chemicals as a form of prevention, protection, and control to combat diseases that affect plants is a feasible solution involving control measures. However, due to the emergence of microorganisms resistant to these products, new tests need to be performed in the laboratory, requiring the effort of the specialist in phytopathology and in order to investigate these microorganisms. One of the most common methods used includes laboratory tests, periodically verifying the growth of the fungal colony with measurements using ruler or caliper, but this method is imprecise. The study was developed using images containing Petri dishes with growing fungus colonies, comparing the manual method performed by the specialist in Phytopathology and by images processing. For this, processes were developed involving region segmentation by color analysis and unnecessary information removal to measure the size of colony. It was possible to verify the application and potential of the method developed for creating mobile applications. Therefore, this work presents a method for measurement of the fungal colony on Petri dishes from isolates of the fungus Corynespora cassiicola, using techniques involving digital image processing, with the purpose of assisting the phytopathologist professional, providing other means besides the visual analysis.

RESUMO: O objetivo deste trabalho foi avaliar a eficiência e a praticidade de métodos de inoculação de Sclerotinia sclerotiorum, para uso na seleção de cultivares de soja resistentes ao mofo-branco. Avaliaram-se quatro métodos de inoculação, em plantas no estádio fenológico V3/V4. Aos três e sete dias após a inoculação, mediu-se o comprimento da lesão na haste das plantas. As cultivares de soja BRS 8460RR, BRSGO Ipameri e P98Y11 apresentaram as menores lesões. O método de inoculação por meio de ponteira no pecíolo é o mais eficiente e mais prático para avaliar a resistência ao mofo?branco em soja. ABSTRACT: The objective of this work was to evaluate the efficacy and usefulness of methods of Sclerotinia sclerotiorum inoculation for screening soybean cultivars resistant to white mold. Four inoculation methods were evaluated in plants at the V3/V4 phenological stages. Stem lesion length was measured three and seven days after inoculation. The soybean cultivars BRS 8460RR, BRSGO Ipameri, and P98Y11 had the smallest stem lesions. The inoculation method with pipette tip on the petiole is the most effective and practical to evaluate soybean resistance to white mold.

Resumo: O objetivo deste trabalho foi elaborar e validar um protocolo de detecção simultânea, via reação em cadeia da polimerase multiplex (PCR multiplex), de regiões genômicas do tomateiro (Solanum lycopersicum) associadas a fatores de resistência às três raças fisiológicas de Fusarium oxysporum f. sp. lycopersici (FOL). Os pares de iniciadores empregados foram SSR-67 (específico para o gene I-1), TFusrr (específico para o gene I-2) e SSRD (específico para o gene I-3). Os resultados de genotipagem com marcadores moleculares foram comparados aos resultados de fenotipagem de uma coleção de germoplasma de tomateiro, em bioensaios de inoculação de isolados das três raças de FOL em plântulas, pelo método de imersão das raízes. A resistência ou a suscetibilidade foi confirmada por PCR, por meio de visualização dos âmplicons específicos para as regiões-alvo ligadas aos fatores de resistência às distintas raças de FOL. O protocolo elaborado para o uso conjunto dos marcadores moleculares, em PCR multiplex, permite a seleção de acessos de tomateiro resistentes às raças 1, 2, e 3 de F. oxysporum f. sp. lycopersici de maneira similar à realizada com a utilização de cada um separadamente. O PCR multiplex representa uma ferramenta viável para monitorar a incorporação desses fatores de resistência em linhagens de tomateiro. Abstract: The objective of this work was to develop and validate a protocol for simultaneous detection by multiplex polymerase chain reaction (multiplex PCR) of tomato (Solanum lycopersicum) genomic regions associated with factors of resistance to three physiological races of Fusarium oxysporum f. sp. lycopersici (FOL). The employed primer pairs were SSR-67 (specific to the I-1 gene), TFusrr (specific to the I-2 gene), and SSRD (specific to the I-3 gene). Genotyping results with molecular markers were compared with the phenotyping ones of a tomato germplasm collection, in bioassays of isolate inoculation of the three FOL races in seedlings by root dipping. The resistance or susceptibility was confirmed by PCR, through the visualization of specific amplicons corresponding to the target regions linked to the factors of resistance to distinct FOL races. The elaborated protocol for the joint use of the molecular markers, by multiplex PCR, allows of the selection of tomato accessions that are resistant to the races 1, 2, and 3 of F. oxysporum f. sp. lycopersici in a similar way to that done with each one separately. PCR multiplex is a viable tool to monitor the incorporation of these resistance factors into tomato inbred lines.

Resumo: O objetivo deste trabalho foi avaliar a reação de 48 acessos de tomateiro (Solanum lycopersicum), inclusive de espécies selvagens, a diferentes isolados das três raças de Fusarium oxysporum f. sp. lycopersici (FOL). Utilizaram-se marcadores moleculares ligados aos genes de resistência I-1, I-2 e I-3. A combinação de bioensaios e marcadores moleculares específicos mostrou elevada correlação para a maioria dos acessos. Acessos de S. peruvianum e S. corneliomuelleri apresentaram resistência contra todas as raças de FOL; a introgressão de fatores de resistência destes genótipos em germoplasma-elite de tomateiro é de elevado interesse para o melhoramento genético desta cultura.

International audience; A loop-mediated isothermal amplification (LAMP) assay was developed and compared to polymerase chain reaction (PCR), nested PCR, and selective isolation assays for detection of Xanthomonas albilineans, the causal agent of sugarcane leaf scald. The pathogen was isolated on selective medium from 44 out of 45 (98%) samples taken from symptomatic stalks, and from 44 out of 70 (63%) samples from asymptomatic stalks that were collected from plots with symptomatic stalks. Forty-two (93%), 41 (91%), and 42 (93%) symptomatic samples tested positive by LAMP, PCR and nested PCR, respectively. The pathogen was detected in 19 (27%), 8 (11%), and 25 (36%) of the 70 asymptomatic samples by LAMP, PCR and nested PCR, respectively. Symptomatic stalks were mainly, but not always, associated with high populations of the pathogen (10(7)-10(9) CFU/ml), and asymptomatic stalks with low populations (< 10(3) CFU/ml) or no bacteria. Although our LAMP and nested PCR methods detected 10 CFU/ml of X. albilineans in suspensions prepared with pure culture, they sometimes failed to detect the pathogen in samples with low pathogen populations. Isolation on selective medium along with another method should therefore be used for detection of the pathogen in asymptomatic stalks, especially in quarantine programs.

Field trials were carried out to evaluate six treatments combining biological agents and chemical fungicides applied via chemigation against white mold ( Sclerotinia sclerotiorum ) on processing tomatoes. The experiment was performed in Goiânia, Brazil, with tomato hybrid Heinz 7155 in 2009 and 2010 in a field previously infested with S. sclerotiorum sclerotia. Treatments were arranged in a randomized complete block design in a 2 × 3 factorial structure (with and without Trichoderma spp. 1.0 × 10 9 viable conidia mL −1 ha −1 ) × fluazinam (1.0 L ha −1 ), procimidone (1.5 L ha −1 ) and control, applied by drip irrigation. Treatments were applied three times 10 days apart, starting one month after transplanting. Each treatment consisted of plots with three 72-meter rows with four plants m −1 and 1.5 m spacing between rows, with three replications. Based on disease incidence evaluated weekly, the area under the disease progress curve (AUDPC) was obtained. Yield and its components were evaluated in addition to fruit pH and °Brix. Results were subjected to ANOVA, Scott-Knott (5%), and regression analysis. Biocontrol using Trichoderma spp. via chemigation singly or in combination with synthetic fungicides fluazinam and procimidone reduced AUDPC and increased fruit yield up to 25 t ha −1 . The best treatment for controlling white mold also increased pulp yield around 1.0 and 7.0 t ha −1 in 2009 and 2010, respectively. The present work demonstrated the advantages of white mold biological control in processing tomato crops, where drip irrigation favored Trichoderma spp. delivery close to the plants and to the inoculum source.

Leaf scald is one of the major bacterial diseases affecting sugarcane crop. Previous studies have reported the difficulty detection of the pathogen by conventional PCR when applied in asymptomatic plant material, where the pathogen population level is find below the detectable limit by conventional PCR. Because of this factor and the resilience of Xanthomonas albilineans at latent stage, our study aimed to enhance protocols, both extraction pro­cedures of sugarcane juice and DNA extraction protocols from sugarcane juice for the detection of Xanthomonas albilineans even when the residual bacterial sample is minimal. We tested four techniques for sugarcane juice extraction: compressor, pressing, macerated and bacterial flow in water and four DNA extraction protocols, two of them considered quick or simple, a CTAB procedure and one commercial Kit. The results indicated that conven­tional PCR was not able to detect the pathogen in asymptomatic stalks. However, working on Nested-PCR, we could detect X. albilineans in latently infected plants in 100% of samples when the vascular fluid was extracted by bacterial water flow following a centrifugation, adding TAE and boiling as DNA extraction method.

Corynespora cassiicola, agente causal da mancha alvo, causa prejuízos econômicos em diversas culturas. Como a disponibilidade de protocolos padronizados para a produção de inóculo facilitam a condução de testes de patogenicidade, os objetivos deste trabalho foram analisar o crescimento micelial em diferentes temperaturas; avaliar o crescimento micelial e a esporulação de isolados obtidos de diferentes hospedeiros em diferentes regimes de luz; avaliar o efeito da duração de umidade contínua para a máxima germinação dos esporos in vitro e a patogenicidade de sete isolados de C. cassiicola em diversos hospedeiros. As temperaturas para o maior crescimento micelial variaram de 23,3 a 29,5ºC; o crescimento de oito isolados foi indiferente aos regimes de luz, enquanto os outros seis foram mais influenciados pelo escuro contínuo; a maioria dos isolados esporulou mais sob luz contínua; cinco a vinte horas de umidade contínua foi a variação de tempo para que 85% dos esporos germinassem; quanto à patogenicidade, foi observado que o algodoeiro, o meloeiro e o pepineiro foram os hospedeiros mais suscetíveis, e menos suscetíveis, o tomateiro, aceroleira e o cafeeiro. Para produção massal de inóculo de C. cassiicola recomenda-se utilizar a temperatura de 25ºC sob luz contínua. Corynespora cassiicola is the causal agent of target spot on several crops of economic importance. Since the availability of standardized protocols for inoculum production makes the conduction of patogenicity tests easier, the objectives of this work were to evaluate the mycelial growth under different temperatures, to evaluate the mycelial growth and spore production under different photoperiods for isolates obtained from different hosts, to evaluate the effect of continuous humidity on spore germination, and the pathogenicity of seven isolates of C. cassiicola on several hosts. Temperatures between 23,3 and 29,5ºC allowed the best growth of the isolates. The growth of eight isolates did not respond to the photoperiods used whereas six isolates were sensitive to the dark. The best sporulation for the majority of isolates was under continuous light. Five to twenty hours of continuous humidity were enough for 85% of the spores to germinate. As for pathogenicity, cotton, melon and cucumber were the most susceptible hosts, while tomato, coffee and Antilles cherry were the least susceptible. For massal production of C. cassiicola inoculum, a temperature of 25ºC under continual light is recommended.

Soybean (Glycine max L. Merrill) is infected by a large number of fungal pathogens, among them white mold agent [Sclerotinia sclerotiorum (Lib) de Bary]. The objective of this study was to verify the effect of the seed-processing stages on the physical and physiological qualities and on the incidence of S. sclerotiorum in soybean seeds. In this study, seeds from eight cultivars coming from production fields naturally infested in the counties of the State of Goiás, Brazil, from two harvests (2009/2010 and 2010/2011), were used. Samples were collected in the processing stages: hopper, pre-cleaning, discard one (from pre-cleaning), cleaning, sieve classifiers, spiral, gravity table, and discard two (after cleaning until processing ending). The following parameters were evaluated: seed- moisture content, physical purity, germination and tetrazolium. Additional tests and the detection of S. sclerotiorum in paper roll and the neon method were performed. The processing of soybean seeds improves the physical and physiological quality of the seed lots, in addition to eliminating sclerotia. The stages of pre-cleaning and cleaning significantly reduce sclerotia in seed lot. The amount of sclerotia in the sample is not necessarily correlated with the incidence of S. sclerotiorum in mycelial form.

Soybean is an important crop in the economical agriculture of Brazil and it has productive potential compromised by a variety of diseases affecting the crop such as soybean rust (Phakopsora pachyrhizi). The aim of this study was to evaluate the efficiency of incorporating fluquinconazole into the soybean seed treatment in the management of the disease, associated with spray of different fungicides on leaves. The work consisted of two trials side by side on the field. The first trial consisted of several fungicides used to control soybean rust (azoxistrobin, cyproconazole, trifloxystrobin, tebuconazole and prothioconazole) and seed treatment with carbendazim + thiram, and fluquinconazole. The second trail was identical to the first, but without the use of fluquinconazole. The experiment was carried out into two localities – Goiânia (GO) and Senador Canedo (GO). In both experiments, fungicides applied on leaves were effective controlling soybean rust, however the incorporation of fluquinconazole on the soybean seed treatment did not increase the control of the disease since neither it delayed the onset of the disease nor significantly increased the productivity of the crop. A soja é uma das principais culturas de exploração econômica no Brasil, mas tem seu potencial produtivo comprometido por uma série de doenças que afetam a cultura. O objetivo do presente trabalho foi avaliar a eficiência da incorporação de fluquinconazol ao tratamento de semente de soja, no manejo da ferrugem asiática (Phakopsora pachyrhizi), associado a diferentes fungicidas na parte aérea. O trabalho constou de dois ensaios dispostos lado a lado no campo. O primeiro ensaio constou de vários fungicidas empregados no controle de ferrugem asiática da soja (azoxistrobina, ciproconazol, trifloxistrobina, tebuconazol e protioconazol) e de tratamento das sementes com carbendazim + thiram e fluquinconazol. O segundo ensaio foi idêntico ao primeiro, mas sem a utilização de fluquinconazol. Esse experimento foi realizado em dois locais – Goiânia (GO) e Senador Canedo (GO). Em ambos os locais, os fungicidas aplicados via foliar foram eficientes no manejo da ferrugem da soja, mas a incorporação de fluquinconazol não aumentou significativamente o controle do fungo P. pachyrhizi, uma vez que não retardou o aparecimento da doença nem acarretou ganhos significativos de produtividade.

White mold, caused by the fungus Sclerotinia sclerotiorum , is considered the second most destructive disease affecting soybean crops. The pathogen is controlled by integrating different methods, including genetic resistance. However, genotype selection techniques often lack the desired efficiency. As such, the aim of this study was to use sensitivity to oxalic acid as a selection method for white mold-resistant soybean genotypes and compare the results against soybean S. sclerotiorum infection in two agroecosystems, namely Barreiras (Bahia state – BA) and Jatai (Goias state – GO). Eleven genotypes were planted and evaluated in the Barreiras region and 10 in Jatai, three of which were common to both areas. Assessments in the field involved analyzing white mold incidence, growth cycle and yield. For the oxalic acid-based selection method, the soybean genotypes were exposed to a 20 mM oxalic acid solution and wilting was assessed. In oxalic acid sensitivity testing, both the resistant and susceptible genotypes mirrored the resistance expressed under field conditions. Thus, oxalic acid sensitivity testing was considered suitable for use in breeding programs aimed at selecting white mold-resistant genotypes.

No presente trabalho foi estudado o comportamento da população de Compsocerus violaceus (White, 1853) (Coleoptera, Cerambycidae) em relação à fauna de cerambicídeos coletados em pomar de citros misto conservado e abandonado, formado pelas tangerinas cravo e rio, laranjas baianinha e natal, tangor sabará e limão cravo. As coletas foram quinzenais e realizadas através de armadilhas plásticas iscadas com melaço de cana a 20%. Quinzenalmente também se procedia à troca da isca. O período de coleta foi de agosto de 1983 a julho de 1985. Foram estudados os parâmetros ecológicos de abundância relativa, constância, freqüência e dominância. Verificou-se também a influência de alguns fatores climáticos sobre a população da espécie. Foram coletados 405 adultos sendo, 180 machos e 225 fêmeas no pomar abandonado e no conservado 253 adultos, sendo 96 machos e 163 fêmeas. Desse total, 39% ocorreram no pomar conservado e 61%, no abandonado. O período de maior ocorrência da espécie foi verificado nos meses de novembro e dezembro, nos dois pomares. Não houve correlação entre os fatores meteorológicos estudados com a flutuação da espécie. Entre os parâmetros ecológicos estudados, C. violaceus foi classificado como ";comum e muito abundante”, “acidental e constante”, apresentou uma freqüência de 10,31% entre as espécies coletadas, e foi considerado “dominante” nos dois pomares, obtendo a mesma classificação das espécies Dorcacerus barbatus, Macropophora accentifer, Acathoderes jaspidea, Chlorida festiva e Trachyderes spp., coleobrocas reconhecidas como pragas de grande importância econômica para as plantas frutíferas no Brasil. PALAVRAS-CHAVE: Inseto; praga; Compsocerus; citros. The present work analyses the population behavior of Compsocerus violaceus (White, 1853) (Coleoptera, Cerambycidae), related to the fauna of cerambicideos, collected in conserved and rio tangerine, baianinha and natal orange, tangor sabará and cravo lemon. The collections were carried out fortnightly, using a plastic bait trap with 20% molasses. The baits were replaced every two weeks. The collection period ranged from August/1983 to JuIy/1985. The ecological parameters studied included the relative abundance, constancy, frequency and dominance. The influence of some meteorological factors over the species population was also investigated. In the abandoned yard 405 adults were collected, comprising 180 males and 225 females, and in the conserved yard, 253 adults were collected, comprising 96 males and 163 females. From the total insects collected, 39% were from the conserved yard, while 61% came from the abandoned yard. The period showing the highest occurrence was the one comprising the months of November and December, in both yards. No correlation between meteorological factors and species fluctuation could be detected. Among the ecological parameters analyzed, C. violaceus was classified as “common and very abundant”, “accidental and constant”. C. violaceus showed a frequency of 10,31% among the collected species, and was considered “dominant” in both yards, obtaining the classification of Dorcacerus barbatus, Macropophora accentifer, Acathoderes jaspidea, Chlorida festiva and Trachyderes spp., all recognized as dangerous species with a remarkable economic importance for the Brazilian fruit-bearing plants. KEY-WORDS: Insecta; pest; Citrus.

The present work analyses the population behavior of Compsocerus violaceus (White, 1853) (Coleoptera, Cerambycidae), related to the fauna of cerambicideos, collected in conserved and rio tangerine, baianinha and natal orange, tangor sabará and cravo lemon. The collections were carried out fortnightly, using a plastic bait trap with 20% molasses. The baits were replaced every two weeks. The collection period ranged from August/1983 to JuIy/1985. The ecological parameters studied included the relative abundance, constancy, frequency and dominance. The influence of some meteorological factors over the species population was also investigated. In the abandoned yard 405 adults were collected, comprising 180 males and 225 females, and in the conserved yard, 253 adults were collected, comprising 96 males and 163 females. From the total insects collected, 39% were from the conserved yard, while 61% came from the abandoned yard. The period showing the highest occurrence was the one comprising the months of November and December, in both yards. No correlation between meteorological factors and species fluctuation could be detected. Among the ecological parameters analyzed, C. violaceus was classified as “common and very abundant”, “accidental and constant”. C. violaceus showed a frequency of 10,31% among the collected species, and was considered “dominant” in both yards, obtaining the classification of Dorcacerus barbatus, Macropophora accentifer, Acathoderes jaspidea, Chlorida festiva and Trachyderes spp., all recognized as dangerous species with a remarkable economic importance for the Brazilian fruit-bearing plants. KEY-WORDS: Insecta; pest; Citrus. No presente trabalho foi estudado o comportamento da população de Compsocerus violaceus (White, 1853) (Coleoptera, Cerambycidae) em relação à fauna de cerambicídeos coletados em pomar de citros misto conservado e abandonado, formado pelas tangerinas cravo e rio, laranjas baianinha e natal, tangor sabará e limão cravo. As coletas foram quinzenais e realizadas através de armadilhas plásticas iscadas com melaço de cana a 20%. Quinzenalmente também se procedia à troca da isca. O período de coleta foi de agosto de 1983 a julho de 1985. Foram estudados os parâmetros ecológicos de abundância relativa, constância, freqüência e dominância. Verificou-se também a influência de alguns fatores climáticos sobre a população da espécie. Foram coletados 405 adultos sendo, 180 machos e 225 fêmeas no pomar abandonado e no conservado 253 adultos, sendo 96 machos e 163 fêmeas. Desse total, 39% ocorreram no pomar conservado e 61%, no abandonado. O período de maior ocorrência da espécie foi verificado nos meses de novembro e dezembro, nos dois pomares. Não houve correlação entre os fatores meteorológicos estudados com a flutuação da espécie. Entre os parâmetros ecológicos estudados, C. violaceus foi classificado como ";comum e muito abundante”, “acidental e constante”, apresentou uma freqüência de 10,31% entre as espécies coletadas, e foi considerado “dominante” nos dois pomares, obtendo a mesma classificação das espécies Dorcacerus barbatus, Macropophora accentifer, Acathoderes jaspidea, Chlorida festiva e Trachyderes spp., coleobrocas reconhecidas como pragas de grande importância econômica para as plantas frutíferas no Brasil. PALAVRAS-CHAVE: Inseto; praga; Compsocerus; citros.

A preferência para oviposição e/ou alimentação de Macropophora accentifer foi observada em pomar misto abandonado, formado por tangerinas-cravo e rio, laranjas baianinha e natal, tangor-sabará e limão-cravo em plantas de 5 a 20 anos de idade e plantado no espaçamento de 10m. As fêmeas da espécie foram marcadas com tintas na região do pronoto. As coletas foram manuais, as marcações, liberações e recapturas foram realizadas de setembro a novembro e de março a maio. As fêmeas, num total de 231, coletadas em cada uma das seis variedades, foram marcadas e imediatamente liberadas em todas as outras variedades, inclusive na mesma variedade onde foi coletada. As recapturas foram realizadas dez dias após cada liberação. Foram realizadas 30 liberações e 50 recapturas. A preferência foi determinada levando-se em consideração o número de fêmeas que permaneceram, retornaram ou migraram para cada variedade de citros. Observou-se que 2,16% retornaram para a variedade onde foram coletadas, 59,31% permaneceram na variedade onde foram liberadas, 30,74% migraram para outras variedades e 7,79% não foram recapturadas. Concluiu-se que a tangerina-cravo apresentou 46,75% de preferência, seguida da tangor-sabará com 16,88%, baianinha com 10,82%, natal com 9,95% e tangerina-rio com 7,8%. O limão-cravo não apresentou nenhuma preferência. The preference for oviposition and/or alimentation was observed in Macropophora accentifer females in a mixed yard, composed by cravo and rio tangerines, baianinha and natal oranges, tangor sabará and cravo lemon. The plants were 5 to 20 years old, and the yard was abandoned and cultivated with a distance of 10m between plants. The females were labeled with dye ink in the pronotum region. Manual collection, labeling, release and recapture were carried out in September/October/November, and in March/April/May. A total of 231 females insects were collected in each variety, labeled and immediately released in different varieties, including those who collected firstly. The recaptures were carried out twelve days after each release; 30 releases and 50 recaptures were performed. The preference was determined considering the number of female insects that remained, returned or migrated to each one of the citrus varieties. It was observed that 2.16% of the females returned to the varieties where they were previously collected, 59.31% remained in the variety where they were released, 30.74% migrated to different varieties, and 7.79% were not recaptured. The cravo tangerine presented 46.75% of preference, followed by tangor sabará with 16.88%, baianinha orange with 10.82%, natal orange with 9.95% and rio tangerine with 7.8%. Cravo lemon did not present any preference by the insect females.

RESUMOMurchas vasculares em tomateiro constituem importante grupo de doenças incitadas por patógenos habitantes de solos, com destaque para Fusarium oxysporumf. sp. lycopersici, que ocasiona perdas significativas de produção. A introgressão de genes que expressam resistência é a principal medida de controle, mas, devido à rápida emergência de raças que suplantam a resistência, vem aumentando a importância do biocontrole, em integração com o controle genético. Objetivou-se avaliar a capacidade de isolados de rizobactérias, especialmente do gênero Bacillus, como agentes de biocontrole da murcha de fusário em tomateiro. O ensaio de laboratório consistiu na verificação da habilidade de os isolados atuarem como inibidores de crescimento micelial, além da detecção de genes envolvidos na expressão de polipeptídios de ação antimicrobiana. Em casa-de-vegetação, o ensaio foi composto por sementes microbiolizadas e adição, ao solo, de suspensão de propágulos de cada rizobactéria, no momento do transplantio das mudas de tomateiro. Todos os isolados de rizobactérias apresentaram controle variável do patógeno in vitro. Os isolados UFG-07 e UFG-10, com alta similaridade a Bacillus subtilis e Bacillus circulans, destacaram-se na supressão da doença. Resultados da PCR detectaram genes-alvo para expressão de polipeptídios, o que reforça a hipótese da ação de substâncias antimicrobianas no biocontrole. ABSTRACTVascular wilting in tomato plants constitutes an important group of diseases incited by soil inhabiting pathogens, especially Fusarium oxysporum f. sp. lycopersici, that causes significant production losses. The introgression of genes that express specific resistance is considered the main control method, however, due to the rapid emergence of races that suppress resistance, biocontrol has been presented as an option to be integrated with genetic control methods. This study aimed at evaluating the ability of rhizobacteria isolates, especially from the Bacillus genus, as biological control agents of Fusarium wilt in tomato plants. The laboratory assay was carried out to verify the ability of the isolates in acting as inhibitors of mycelial growth, besides detecting the genes involved in the expression of polypeptides with antimicrobial action. In the greenhouse, the assay comprised of microbiolized seeds and addition of a suspension of propagules of each rhizobacteria to the soil at the moment of transplanting the tomato seedlings. All the rhizobateria isolates showed variable control levels of the pathogen in vitro. The UFG-07 and UFG-10 isolates, with high similarity with Bacillus subtilis and Bacillus circulans, excelled in the disease suppression. PCR results detected target genes for expression of polypeptides, what reinforces the hypothesis of action of antimicrobial substances in biocontrol.

O experimento foi desenvolvido no município de Silvânia (GO), em pomar comercial de uva `Patrícia' (IAC 871 - 41) durante o período de fevereiro a outubro de 2003. O objetivo deste trabalho foi avaliar o comportamento fenológico e as características dos cachos e das bagas da cv. Patrícia em diferentes épocas de poda (13/3, 28/3, 12/4 e 27/4). A duração do ciclo (poda - colheita) foi de 152, 172, 185 e 178 dias para as podas realizadas em 13/3, 28/3, 12/4 e 27/4 respectivamente. As épocas de podas não afetaram significativamente o tamanho e a forma dos cachos, entretanto, grandes e medianamente compactos com comprimento médio de 20,52 cm. O maior diâmetro de baga foi encontrado na poda realizada em 27/4 com 19,14 mm, padrões considerados adequados para a cultivar. As diferentes épocas de poda não exerceram influência sobre os teores de sólidos solúveis totais, com média de 18,4 ºBrix. Todavia, houve variação significativa para a acidez total titulável, evidenciada nas podas de 13/3 e 27/4, respectivamente, com 1,44 e 0,87g de ácido tartárico/100 mL de mosto de uva. As diferentes épocas de poda afetaram significativamente a relação SST/ATT, sendo a menor relação encontrada na poda realizada em 13/3 com apenas 13,0 e a maior na poda de 27/4 com 21,9.The experiment was developed in the council of Silvânia, State of Goiás, in commercial orchard of grape `Patrícia' (IAC 871 - 41) during the period of February to October of 2003. The objectives of this work were to evaluate the phenologycal behavior and the characteristics of the bunches and berries of Patrícia cultivar in different pruning times (March 13, March 28, April 12 and April 27). Durations of the stage (pruning - harvest) were of 152, 172, 185 and 178 days for the prunings accomplished on March 13, March 28, April 12, and April 27, respectively. The pruning times did not affect the size and the form of the bunches significantly, however, these became large with length of about 20.52 cm. The largest berry diameter was found in the pruning accomplished on April 27 with 19.14 mm, patterns considered appropriate for cultivation. The different pruning dates did not show influence on total soluble solids, with an average of 18.4 ºBrix, however there was no variation for the total acidity titratable, evidenced in the prunings of March 13, and April 27, respectively, with 1.44 and 0.87g of tartaric acid /100 mL of grape juice. The different pruning dates affected significantly the SST/ATT relationship, being the smallest relationship found in the pruning date of March 13 with 13.0 and the largest in the pruning date on April 27 with 21.9.

The cultivated area devoted to rice crops (Oryza sativa) in Brazil has expanded in recent years, along with improvements in yield. This has prompted the continuous exchange of material from active germplasm banks between government breeding programs. When placed in a greenhouse for multiplication purposes, rice accessions resulting from exchanges between USDA-ARS (United States Department of Agriculture - Agricultural Research Service) showed little or no germination. The accessions were sent to the tissue culture laboratory of BAG-CNPAF (Embrapa National Rice and Bean Research Center) to recover embryos by aseptically removing the seed coat of 10 seeds from each accession. Bacterial colony growth concomitant to germination inhibition was observed in some accessions, from which four bacterial isolates were obtained. Made available in DSpace on 2017-12-26T23:23:54Z (GMT). No. of bitstreams: 1 CNPAF2018pdv102n1.pdf: 213919 bytes, checksum: c3d290b54a0663e654d67513d579c97c (MD5) Previous issue date: 2017-12-18 Disease notes.

O fungo Corynespora cassiicola, agente causal da mancha-alvo em soja, tem ocorrido com frequência na região Centro-Oeste do Brasil e pode, sob condições de alta temperatura e alta umidade, causar sérios danos à cultura. O uso de cultivares resistentes ao patógeno é recomendado, porém são poucas as disponíveis no mercado. Este trabalho foi realizado visando avaliar a reação de doze cultivares comerciais de soja inoculados com C. cassiicola, em casa de vegetação e no campo. A severidade foi avaliada utilizando escala diagramática de severidade da mancha-alvo. As cultivares menos suscetíveis ao patógeno na casa de vegetação foram BRSGO 7960 e BRS Sambaíba e as mais suscetíveis foram BMX Potência RR e M-SOY 7908 RR. No campo, as cultivares menos suscetíveis foram M-SOY 8866, M-SOY 7908 RR e BMX Potência RR e as mais suscetíveis foram BRSGO 8360 e BRS Tracajá. The fungus Corynespora cassiicola, the causal agent of soybean target spot, frequently occurs in the Brazilian midwestern region. Under favorable climate conditions it can cause serious damage to this crop. The use of resistant cultivars is recommended although there are only a few available in the market. This investigation was carried out to evaluate the reaction of twelve soybean commercial cultivars to C. cassiicola. Severity was evaluated using a diagrammatic scale of target spot. The less susceptible cultivars in greenhouse were BRSGO 7960 and BRS Sambaíba and the most susceptible were BMX Potencia RR and M-SOY 7908 RR. In the field, the less susceptible cultivars were M-SOY 8866, M-SOY 7908 RR and BMX Potência RR and the most susceptible were BRSGO 8360 and BRS Tracajá.

Soybean is an important crop in the economical agriculture of Brazil and it has productive potential compromised by a variety of diseases affecting the crop ...

Devido à ausência de escala diagramática para a mancha alvo do pepineiro, causada por Corynespora cassiicola, verificou-se a necessidade de um sistema de quantificação da doença, que proporcionasse maior rapidez e precisão na obtenção dos resultados. Para tanto, uma escala diagramática foi elaborada, considerando-se o limite máximo e mínimo de severidade da doença observados no campo. Os valores intermediários da escala seguiram incrementos logarítmicos para os sintomas da mancha alvo (0,3%; 0,8%; 2%; 5%; 11,5%; 25%; e 46%). Para a validação da escala, oito avaliadores quantificaram a severidade da doença, em cinquenta folhas com diferentes níveis de doença. Inicialmente, a estimativa da severidade foi feita sem auxílio da escala. A seguir, os mesmos avaliadores, utilizando a escala diagramática proposta, estimaram a severidade nas mesmas folhas avaliadas anteriormente. As avaliações com a escala diagramática foram mais precisas e acuradas, nas estimativas da maioria dos avaliadores. A escala diagramática proposta foi considerada adequada para estimar a severidade da mancha alvo, em folhas de pepineiro, e poderá ser utilizada em estudos epidemiológicos e de avaliação de estratégias de controle desta doença. The lack of a diagrammatic scale to evaluate the cucumber target spot, caused by Corynespora cassiicola, led to the development of an assessment system for a faster and more reliable way to quantify this disease. So, a diagrammatic scale was elaborated considering the maximum and minimum severity limits of the disease observed in the field. The intermediate values followed logarithmic increments for the target spot symptoms (0.3%, 0.8%, 2%, 5%, 11.5%, 25%, and 46%). For validating the scale, eight raters quantified the disease severity on fifty leaves infected with different levels of the disease. Initially, the severity estimation was carried out without the aid of the scale. Then, the same raters used it to estimate the severity on the same leaves previously assessed. Assessments with the aid of the diagrammatic scale were more precise and accurate, according to most of the raters. The proposed diagrammatic scale was considered adequate to estimate the target spot severity in cucumber leaves, and it can be used in epidemiologic studies and in evaluation strategies for controlling this disease.

The fungus Corynespora cassiicola is the causal agent of target spot in cucumber. Under favorable climatic conditions it can cause serious damage in this horticultural crop. In Brazil, there exists not enough knowledge to determine efficient control measures to the disease. This investigation was carried out to evaluate: a) the reactions of nine cucumber hybrids to C. cassiicola; b) the sensibility of six isolates of C. cassiicola to fungicides in vitro (captan, chlorothalonil, mancozeb, azoxystrobin, difenoconazole, carbendazin, tebuconazole and thiophanate-methyl), used in concentrations of 0, 1, 10, 100 and 1,000 µg mL-1 of active ingredient and c) protective and curative chemical treatments with the same fungicides used in vitro in cucumber plants inoculated with C. cassiicola. The cucumber hybrids were evaluated using the scale of notes and diagrammatic of target spot severity. The more resistant hybrids to the pathogen were Taisho, Nikkey, Yoshinari and Safira. The difenoconazole fungicide caused the most mycelial growth inhibition (MGI) and showed the lowest ED50. Thiophanate-methyl was the worst fungicide, it did not inhibit the mycelial growth of the fungus. Azoxystrobin was the most efficient in controlling the disease, although it has to be registered in Ministry of Agriculture, Livestock and Food Supply in Brazil before its recommendation. O fungo Corynespora cassiicola, agente causal da mancha alvo em pepino, pode, sob condições de alta temperatura e alta umidade, causar sérios danos à cultura. No Brasil, não se tem conhecimento suficiente sobre um manejo adequado dessa doença. Este trabalho foi realizado visando avaliar: a) a reação de nove híbridos de pepino desafiados por C. cassiicola; b) a sensibilidade in vitro de seis isolados de C. cassiicola a fungicidas (captan, clorotalonil, mancozeb, azoxystrobin, difenoconazole, carbendazin, tebuconazole e tiofanato-metílico), utilizados nas concentrações de 0, 1, 10, 100 e 1.000 µg mL-1 de ingrediente ativo e c) o tratamento químico preventivo e curativo com os mesmos fungicidas testados in vitro, em plantas de pepino, inoculadas com C. cassiicola. A severidade foi avaliada utilizando escalas de notas e diagramática de severidade da mancha alvo. Os híbridos mais resistentes ao patógeno foram Taisho, Nikkey, Yoshinari e Safira. O fungicida difenoconazole proporcionou as maiores inibições de crescimento micelial (ICM) do patógeno in vitro e a menor dose efetiva capaz de inibir o crescimento micelial em 50% (DE50); já tiofanato-metílico foi o pior, sendo incapaz de inibir o crescimento micelial do fungo. Quanto à aplicação dos fungicidas de forma preventiva e curativa, em plantas de pepino, azoxystrobin foi o mais eficiente no controle da doença, porém para sua utilização há necessidade de seu registro junto ao Ministério da Agricultura, Pecuária e Abastecimento.