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Foliar nematodes (Aphelenchoides spp.) are known to be parasites of tobacco in restricted areas, but symptoms caused by A. besseyi in tobacco are not well characterized, despite the great importance of this nematode worldwide. This study aimed to evaluate the host reaction of four Nicotiana tabacum cultivars (Comum, Xanthi, Samsun, and TNN) and N. benthamiana cultivar Comum to A. besseyi and to characterize the symptoms and the parasitism of this nematode. Two experiments were conducted under greenhouse conditions with controlled humidity and temperature, in which the plants were inoculated with 600 A. besseyi. At 30 days after inoculation (DAI), nematodes present in the soil, roots, and shoot parts were extracted, and roots and shoot tissues were stained with acid fuchsin. A high number of A. besseyi was obtained per gram of shoot tissues (125 to 2,169 nematodes), and severe symptoms were observed in leaves and inflorescences of all cultivars. The symptoms included foliar distortion and deformation, necrotic spots delimited by the veins, flower abortion, and poor development of plants. In addition, A. besseyi was observed to penetrate tobacco roots at 30 DAI, and nematodes were also observed in the foliar mesophyll, inflorescences, and stems, a parasitism that has not been previously reported in tobacco plants. The disease caused by A. besseyi in tobacco could be a concern for growers in southern and northeastern Brazil because this nematode can cause severe damage to the marketable leaves of tobacco, reducing its commercial value.

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Several species of nematodes are known to cause losses to cowpea (Vigna unguiculata) throughout the world. In Brazil, Aphelenchoides besseyi was described as causing damage on soybean, cotton, and common bean, but no report was found about the parasitism of this nematode in cowpea. This study aimed to verify the host reaction of cowpea cultivars to A. besseyi. The experiment was conducted under greenhouse conditions, using two A. besseyi populations as inocula, obtained from symptomatic soybean and cotton plants collected in naturally infested fields. Cultivars Imponente, Aracê, Guariba, Tumucumaque, Nova Era, and Tracuateua were inoculated with 500 A. besseyi of each population, separately, into soil, and after 30 days from the inoculation nematodes were extracted from shoot systems. Both populations were able to parasitize all the cowpea cultivars. Independently of the cultivar, cowpea plants exhibited symptoms of leaf deformation similar to those described for soybean, cotton, and common bean and, in addition, severe brooming was observed, with the interior of the stems being porous and necrotic. To our knowledge, this is the first report of parasitism by A. besseyi of cowpea in Brazil, under greenhouse conditions, increasing the list of hosts of this nematode.

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The green stem Aphelenchoides besseyi and gall Meloidogyne incognita phytonematodes cause soybean yield losses. Thus, the objective of this study was to evaluate the effects of different populations of A. besseyi and M. incognita on soybeans. The experiment had 10 treatment groups [T1: control, T2: A. besseyi (500), T3: M. incognita (2,000), T4: A. besseyi (250) + M. incognita (2,000), T5: A. besseyi (500) + M. incognita (2,000), T6: A. besseyi (250) + M. incognita (4000), T7: A. besseyi (500) + M. incognita (4,000) individuals, T8: A. besseyi (250) + M. incognita (8,000), T9: A. besseyi (500) + M. incognita (5,000), and T10: A. besseyi (1,000) + M. incognita (8,000) individuals] with six replicates. Inoculations were done on day 10 after soybean germination, and evaluations were conducted after 60 d. Plant height, shoot fresh weight, root fresh weight, number of pods (NP), pod fresh weight, number of grains (NG), grain yield (GY), amount of A. besseyi in the shoot, and M. incognita in the roots were analyzed. The 500 A. besseyi + 8,000 M. incognita treatment reduced all variables and led to considerable damage to soybean development. In addition, GY, NG, and NP were reduced in the different nematode population density groups, influencing soybean agronomic characteristics.(AU)

Entre as espécies de fitonematoides que provocam perdas de produção à cultura da soja estão os nematoides da haste verde (Aphelenchoides besseyi) e o das galhas (Meloidogyne incognita). Diante disso, o objetivo deste trabalho foi estudar os efeitos de diferentes níveis populacionais de A. besseyi e M. incognita na soja. O experimento foi realizado com nove combinações de diferentes níveis populacionais dos nematoides (T1 ­ Controle não inoculado, T2 - A. besseyi 500 indivíduos, T3 - M. incognita 2000 indivíduos, T4 - A. besseyi + M. incognita 250 + 2000 indivíduos, T5 - A. besseyi + M. incognita 500 + 2000 indivíduos, T6 - A. besseyi + M. incognita 250 + 4000 indivíduos, T7 - A. besseyi + M. incognita 500 + 4000 indivíduos, T8 - A. besseyi + M. incognita 250 + 8000 indivíduos, T9 - A. besseyi + M. incognita 500 + 8000 indivíduos e T10 - A. besseyi + M. incognita 1000 + 8000 indivíduos) e seis repetições. As variáveis analisadas foram: altura de planta, massa fresca da parte aérea (MPA), massa fresca de raízes (MR), número de vagens (V), massa fresca de vagens (MV), número de grãos (G), massa fresca de grãos (MG), quantidade de A. besseyi na parte aérea e de M. incognita nas raízes. O mapa de calor indicou que populações iniciais inoculadas de 500 A. besseyi + 8000 M. incognita apresentou maiores danos ao desenvolvimento da soja, reduzindo todas as variáveis analisadas. As variáveis MG, G e V reduziram na presença de diferentes densidades populacionais das espécies de fitonematoides nematoides, influenciando negativamente o desenvolvimento da soja.(AU)

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Metabolomics is an omics technology that is extremely valuable to analyze all small-molecule metabolites in organisms. Recent advances in analytical instrumentation, such as mass spectrometry combined with data processing tools, chemometrics, and spectral data libraries, allow plant metabolomics studies to play a fundamental role in the agriculture field and food security. Few studies are found in the literature using the metabolomics approach in soybean plants on biotic stress. In this review, we provide a new perspective highlighting the potential of metabolomics-based mass spectrometry for soybean in response to biotic stress. Furthermore, we highlight the response and adaptation mechanisms of soybean on biotic stress about primary and secondary metabolism. Consequently, we provide subsidies for further studies of the resistance and improvement of the crop.

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Phakopsora pachyrhizi is a biotrophic fungus, causer of the disease Asian Soybean Rust, a severe crop disease of soybean and one that demands greater investment from producers. Thus, research efforts to control this disease are still needed. We investigated the expression of metabolites in soybean plants presenting a resistant genotype inoculated with P. pachyrhizi through the untargeted metabolomics approach. The analysis was performed in control and inoculated plants with P. pachyrhizi using UHPLC-MS/MS. Principal component analysis (PCA) and the partial least squares discriminant analysis (PLS-DA), was applied to the data analysis. PCA and PLS-DA resulted in a clear separation and classification of groups between control and inoculated plants. The metabolites were putative classified and identified using the Global Natural Products Social Molecular Networking platform in flavonoids, isoflavonoids, lipids, fatty acyls, terpenes, and carboxylic acids. Flavonoids and isoflavonoids were up-regulation, while terpenes were down-regulated in response to the soybean-P. pachyrhizi interaction. Our data provide insights into the potential role of some metabolites as flavonoids and isoflavonoids in the plant resistance to ASR. This information could result in the development of resistant genotypes of soybean to P. pachyrhizi, and effective and specific products against the pathogen.

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Aphelenchoides besseyi is the causal agent of soybean green stem and foliar retention syndrome known as "Soja Louca II." This nematode has recently been reported parasitizing cotton in Brazil. In Costa Rica, it causes the symptoms known as "amachamiento" and false angular spots in common bean (Phaseolus vulgaris). Due to the great importance of beans to Brazilian agriculture, the objective of this research was to study the pathogenicity of A. besseyi in common bean under greenhouse conditions, including its endoparasitic relationships by staining root and shoot system tissues with fuchsin acid. In addition, A. besseyi was collected and quantified from shoot systems 30 days after inoculation by washing the tissue in water and blender centrifugal flotation. We observed the symptoms of amachamiento, leaf and vein deformation in the expanded trifoliate leaves, and also leaves with necrotic, brown to reddish and angular lesions, characteristics from false angular spot, and deformed stems characterized by enlargement of nodes, retortions, and necrotic lesions. High numbers of nematodes were found inside common bean plants. This is the first report of the pathogenicity and symptoms caused by A. besseyi in common bean in Brazil. These findings are important for development of management strategies to avoid losses on bean cropped in infested areas.

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A model to estimate the damage caused by white mold to soybean yield from experimental field data gathered during the summer season of 2009-10 was generated. Six soybean cultivars were grown on six sites of the Savana (Cerrados) region, resulting in a total of nine separate experiments. The gradient of disease intensity (plant stem incidence) and yield was generated through the application of different fungicides and rates three times over the course of the season. The disease incidence in plant stems was evaluated at the R1, R5.2 and R5.5 growing stages. Manual harvest at the physiological ripening stage was followed by grain drying, threshing, and cleaning. Finally, grain yield was estimated in kg/ha, and regression analysis was performed. Nine linear equations representing the damage function were generated. The mean damage function was y = - 6.7 x + 1,000, where y represents grain yield normalized to 1,000 kg/haand x represents WM incidence in plants. To appraise the damage caused by various disease intensities, these models should first be validated. Damage coefficients may be used to determine the level of economic damage.

Desenvolveu-se um modelo para estimar os danos causados pelo mofo-branco (MB) (Sclerotinia sclerotiorum) na cultura da soja, com dados gerados em experimentos de campo conduzidos na safra de soja de 2009/10. Seis cultivares de soja foram cultivados em seis locais perfazendo um total de nove experimentos em distintas regiões edafoclimáticas na região do Cerrado. O gradiente da intensidade da doença, avaliada em função de incidência de sintomas/sinais em hastes, foi gerado pela aplicação de diferentes fungicidas em momentos e doses distintas. A intensidade da doença foi avaliada, nos estádios fenológicos de R1, R5.2 e R5.5. A colheita foi realizada na maturação fisiológica e o rendimento de grãos expresso em kg/ha. As análises de regressão entre o rendimento de grãos e a incidência da doença foram realizadas para todas as combinações obtidas e geraram nove equações lineares da função de dano. Função de dano média de nove experimentos foi R = 1.000 - 6,7 I (onde R = rendimento de grãos normalizado para 1.000 kg/ha e I incidênciaa do MB em plantas). Para estimar o dano causado por intensidades diferentes da doença, esses modelos devem ser previamente validado. Os coeficientes de dano podem ser usados para determinar o limiar de dano econômico

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Asian Soybean Rust (ASR), caused by the biotrophic fungus Phakopsora pachyrhizi, is a devastating disease with an estimated crop yield loss of up to 90%. Yet, there is a nerf of information on the metabolic response of soybean plants to the pathogen Untargeted metabolomics and Global Natural Products Social Molecular Networking platform approach was used to explore soybean metabolome modulation to P. pachyrhizi infection. Soybean plants susceptible to ASR was inoculated with P. pachyrhizi spore suspension and non-inoculated plants were used as controls. Leaves from both groups were collected 14 days post-inoculation and extracted using different extractor solvent mixtures. The extracts were analyzed on an ultra-high performance liquid chromatography system coupled to high-definition electrospray ionization-mass spectrometry. There was a significant production of defense secondary metabolites (phenylpropanoids, terpenoids and flavonoids) when P. pachyrhizi infected soybean plants, such as putatively identified liquiritigenin, coumestrol, formononetin, pisatin, medicarpin, biochanin A, glyoceollidin I, glyoceollidin II, glyoceollin I, glyoceolidin II, glyoceolidin III, glyoceolidin IV, glyoceolidin VI. Primary metabolites (amino acids, peptides and lipids) also were putatively identified. This is the first report using untargeted metabolomics and GNPS-Molecular Networking approach to explore ASR in soybean plants. Our data provide insights into the potential role of some metabolites in the plant resistance to ASR, which could result in the development of resistant genotypes of soybean to P. pachyrhizi, and effective and specific products against the pathogen.

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RATIONALE: The nematode Aphelenchoides besseyi is the causal agent of green stem and foliar retention, a soybean disease recently described in Brazil. This condition can reduce soybean yield by up to 100%. However, little is known about chemical interactions between the plant and pathogen. Therefore, this work aimed to investigate metabolites from healthy soybean roots and from soybean roots that were inoculated with A. besseyi. METHODS: A. besseyi were multiplied in vitro with Fusarium sp. colonies in Petri dishes for 25 days, and were axenically inoculated into hydroponics healthy soybean plants. The metabolites were extracted from the roots of healthy and A. besseyi-infected plants 16 days post-inoculation. These extracts were analyzed using an untargeted metabolomic method with an ultra-high-performance liquid chromatography/electrospray ionization /tandem mass spectrometry (UHPLC/ESI-MS/MS) and molecular networking approach. RESULTS: Roots from infected plants showed morphological alterations such as shrinkage, darkening, and arching. Similarly, they also showed an increased presence of flavonoids, compared with healthy roots. Compounds such as neobavaisoflavone, glycitin, genistin, and genistein were putatively identified and had greater intensity in inoculated roots. These compounds are linked to the defensive mechanisms in plants against nematodes. Moreover, coumaric acid, also exclusively putatively identified in inoculated roots, shows activity related to inhibition of root growth. CONCLUSIONS: Liquid chromatography, mass spectrometry, and molecular networking approaches proved to be a powerful tool for the metabolomic study of GSFR. This study showed metabolomics differences of protective substances in the roots, evidencing a quick response of the plant to the attack of A. besseyi.

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White mold, caused by Sclerotinia sclerotiorum, is a yield-limiting disease of soybean in Brazil. Uniform fungicide trials have been conducted annually since 2009. Data from 74 cooperative field trials conducted over a 10-year period were assembled. We selected five fungicides applied two times around flowering: dimoxystrobin plus boscalid (DIMO+BOSC), carbendazim plus procymidone (CARB+PROC), fluazinam (FLUZ), fluopyram (FLUO), and procymidone (PROC). For comparison, thiophanate-methyl (TMET) applied four times was also included as a low-cost treatment. Network models were fitted to the log of white mold incidence (percentages) and log of sclerotia mass data (grams/hectare) and to the nontransformed yield data (kilograms/hectare) for each treatment, including the untreated check. Back-transformation of the meta-analytic estimates indicated that the lowest and highest mean (95% confidence interval [CI]) percent reductions in incidence and sclerotia mass were 54.2 (49.3 to 58.7) and 51.6% (43.7 to 58.3) for TMET and 83.8 (79.1 to 87.5) and 87% (81.9 to 91.6) for CARB+PROC, respectively. The overall mean (95% CI) yield responses ranged from 323 kg/ha (247.4 to 400.3) for TMET to 626 kg/ha (521.7 to 731.7) for DIMO+BOSC, but the variance was significantly reduced by a binary variable (30% threshold) describing disease incidence in the untreated check. On average, an increment of 352 kg/ha was estimated for trials where the incidence was >30% compared with the low-disease scenario. Hence, the probability of breaking even on fungicide costs for the high-disease scenario was >65% for the more effective, but more expensive fungicide (FLUZ) than TMET. For the low-disease scenario, profitability was less likely and depended more on variations in fungicide cost and soybean price.

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An apparent decline of fungicide performance for the control of soybean rust in Brazil has been reported but the rate at which it has occurred has not been formally quantified. Control efficacy and yield response to three fungicides applied as single active ingredients (a.i.)-azoxystrobin (AZOX), cyproconazole (CYPR), and tebuconazole (TEBU)-and four applied as mixtures-AZOX+CYPR, picoxystrobin + CYPR, pyraclostrobin + epoxiconazole, and trifloxystrobin + prothioconazole (TRIF+PROT)-were summarized using network meta-analytic models fitted to mean severity and yield data from 250 trials (10-year period). The effect of year was tested on both variables in a meta-regression model. Overall control efficacy ranged from 56 to 84%; the three single-a.i. fungicides performed the poorest (56 to 62%). Yield increase for single-a.i. fungicides was as low as 30% but ranged from 47 to 65% for the premixes. Significant declines in both variables were detected for all fungicides except TRIF+PROT. For TEBU, control efficacy (yield response) declined the most: 78% (18%) to 54% (8%) from 2004-05 to 2013-14. The recent surge of resistant populations of Phakopsora pachyrhizi to both demethylation inhibitor and quinone outside inhibitor fungicides is likely the driving force behind a significant decline after 4 years of fungicide use.

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Como parte de amplo estudo epidemiológico sobre condiçöes de saúde na infancia, uma amostra probabilística de menores de cinco anos residentes no Município de Säo Paulo (n = 305) foi estudada com relaçäo à adequaçäo nutricional de suas dietas. Através do inquérito recordatório do consumo alimentar nas últimas 24 horas evidenciou-se que: a) a partir de um ano de idade, as dietas tornan-se insuficientes para cobrir as necessidades energéticas de grande parte da populaçäo; b) em todas as idades, mas particularmente nos primeiros dois anos de vida, o aporte dietético de ferro está muito abaixo das quantidades recomendadas para o consumo do nutriente; c) em todas as idades, o aporte de proteína e de vitamina A alcança valores satifatórios. Tais achados mostraram-se compatíveis com a avaliaçäo clínico-laboratorial do estado nutricional realizada simultaneamente ao inquérito alimentar. A estratificaçäo social da amostra revelou que o nível sócio-econômico familiar influencia fortemente o consumo energético e, de forma menos intensa, o consumo de ferro. Na discussäo dos prováveis fatores responsáveis pelos déficits dietéticos encontrados, hipóteses distintas säo aventadas para o déficit energético e para o déficit de ferro. No caso do déficit energético, a origem básica do problema pareceria residir no baixo poder aquisitivo da populaçäo que condiciona insuficiente disponibilidade de alimentos e ingestäo quantitativamente deficiente. No caso do déficit de ferro, a mesma hipótese valeria inteiramente apenas a partir da idade de dois anos. Antes desta idade, fatores relacionados ao desmame precoce e ao atraso na introduçäo de alimentos ricos em ferro aparentemente seriam mais importantes.

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Por ocasiäo de um estudo de vários parâmetros clínico-laboratoriais em gestantes normais, os autores observaram uma correlaçäo entre a glicemia de jejum e a concentraçäo da frutosamina. Em 65 gestantes näo se constatou nenhum caso de diabete gestacional nos dois testes usados. Concluíram que a determinaçäo da frutosamina pode ser útil, juntamente com outros testes para triagem do diabete gestacional

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Como parte de investigaçäo epidemiológica sobre condiçöes de saúde na infância, foram estudadas a cobertura e a qualidade da assistência materno-infantil prestada à populaçäo do Município de Säo Paulo. Todas as estimativas do estudo baseiam-se em dados obtidos através de inquérito recordatório aplicado a uma amostra representativa de crianças menores de cinco anos residentes no Município (n = 1.016). A cobertura da assistência pré-natal foi estimada em 92,9

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Através de estudo domiciliar de amostra probabilística de crianças menores de cinco anos (n = 1.016) foram analisadas características dos programas infantis de suplementaçäo alimentar desenvolvidos no Município de S. Paulo, SP (Brasil). A cobertura da suplementaçäo no conjunto da amostra foi de 11,4

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