Genome assembly and transcriptomic analysis to elucidate the ability of Nasonovia ribisnigri to break host plant resistance.

Aphid genomic resources enable the study of complex life history traits and provide information on vector biology, host adaption and speciation. The currant-lettuce aphid (Nasonovia ribisnigri (Hemiptera: Aphididae) (Mosley)) is a cosmopolitan pest of outdoor lettuce (Lactuca sativa (Asterales: Asteraceae) (Linnaeus)). Until recently, the use of resistant cultivars was an effective method for managing N. ribisnigri. A resistant cultivar containing a single gene (Nr-locus), introduced in the 1980s, conferred complete resistance to feeding. Overreliance of this Nr-locus in lettuce resulted in N. ribisnigri's ability to break resistance mechanism, with first reports during 2003. Our work attempts to understand which candidate gene(s) are associated with this resistance-breaking mechanism. We present two de novo draft assembles for N. ribisnigri genomes, corresponding to both avirulent (Nr-locus susceptible) and virulent (Nr-locus resistant) biotypes. Changes in gene expression of the two N. ribisnigri biotypes were investigated using transcriptomic analyses of RNA-sequencing (RNA-seq) data to understand the potential mechanisms of resistance to the Nr-locus in lettuce. The draft genome assemblies were 94.2% and 91.4% complete for the avirulent and virulent biotypes, respectively. Out of the 18,872 differentially expressed genes, a single gene/locus was identified in N. ribisnigri that was shared between two resistant-breaking biotypes. This locus was further explored and validated in Real-Time Quantitative Reverse Transcription PCR (qRT-PCR) experiments and has predicted localisations in both the cytoplasm and nucleus. This is the first study to provide evidence that a single gene/locus is likely responsible for the ability of N. ribisnigri to overcome the Nr-locus resistance in the lettuce host.

Pathogenic parasites in sewage irrigated crops and soil: pattern of occurrence and health implications.

The current study aimed to determine the contamination level by human parasite eggs and cysts of sewage-irrigated soil, food crops and fodder crops. Field trials were conducted on spray-irrigated lettuce and flood-irrigated crops using raw wastewater and fresh water. Findings showed that irrigation by raw wastewater led to crops contamination with parasite eggs and cysts in varying levels. Lettuce samples were positive (27.7%) for one or more helminth eggs including the pathogens Ascaris and Trichuris with an average of 4.7 eggs/kg. Wastewater application caused an increase in lettuce contamination, followed by a decreasing phase. Cessation of irrigation resulted in helminth eggs disappearance within a week. Flood-irrigated crops were contaminated with helminth eggs in levels ranging from 1.5 eggs/kg in alfalfa to 4.75 eggs/kg in coriander. The pathogenic Giardia,Entamoeba histolytica/dispar and commensal amoeba cysts were highly detected reaching 9.97x103 cysts/kg in alfalfa. Parasites highly concentrated in soil, with levels up to 159 eggs/100gdw and 1.3x103 cysts/gdw. Ascaris and Trichuris eggs developed in soil and crops attaining the infective stage. Crops and soil irrigated with fresh water were free from parasite eggs and cysts. The occurrence of pathogens in soil and crops implies health risks for farmers, produce handlers and consumers.

Detection of enteropathogens and research of pesticide residues in Lactuca sativa from traditional and agroecological fairs / Detecção de enteropatógenos e pesquisa de resíduos de agrotóxicos em Lactuca sativa de feiras tradicionais e agroecológicas

Agroecological production represents a new reality in vegetable farming. Thus, the study aimed to search for the presence of pesticides in agroecological samples and microbiological and parasitological contamination in Lactuca sativa L. of agroecological and conventional fairs in Alagoas. Thirty-two samples were collected, a hygienic sanitary checklist was performed, along with coliform, Salmonella spp., Staphylococcus aureus research and Gas Chromatography with Mass Spectrometer (GC-MS) for pesticide research; using two methodologies for parasitological studies. Thirty-two samples were analyzed, with a sanitary adequacy level at 45% and 38% for fairs (agroecological and conventional) respectively, with three samples (9.4%) in total, being adequate to the microbiological pattern according to RDC no. 12/2001. Among the 23 samples which were tested positive for parasites, 69.5% originated from samples extracted at conventional fairs, and 53% of every positive samples presented Entamoeba coli as the main contaminant. All together, no traces of deltamethrin were detected, but in two of the samples a peak retention for diphenoconazole was detected. In conclusion, the fairs represent an adequate environment for human pathogens and indicators. Therefore greater hygiene training of vegetable traders and consumers in the state of Alagoa sis required, especially in conventional fairs, which presented more critical microbiological and parasitological indexes comparing to fairs with agroecological products; however, the presence of difenoconazole in two samples of agricultural fairs suggests accidental contamination or indiscriminate use of this chemical in the production of Lactuca sativa, however, products with agroecological origin represents a better choice for the consumers.

A produção agroecológica representa uma nova realidade no cultivo das hortaliças. Assim, o estudo teve como objetivo verificar a presença de agrotóxicos em amostras agroecológicas e analisar a contaminação microbiológico e parasitológico em Lactuca sativa L. de feiras agroecológicas e convencionais de Alagoas. Foram coletadas 32 amostras, realizando checklist higiênico-sanitário, análises de coliformes, Salmonella spp., Staphylococcus aureus e Cromatografia Gasosa com Espectrômetro de Massas (GC-MS) para pesquisa de agrotóxicos; utilizando-se duas metodologias para estudos parasitológicos. Foram analisadas 32 amostras, com nível de adequação sanitária de 45% e 38% para feiras (agroecológicas e convencionais) respectivamente, sendo três amostras no total (9,4%) adequadas a padrão microbiológico segundo RDC n° 12//2001; Dentre as 23 amostras positivas para parasitos, 69,5% teve origem em amostras de feiras convencionais, e 53% de todas as amostras positivas apresentaram Entamoeba coli como principal contaminante, juntamente, não foi detectado traços de deltametrina, porem foi visualizado em duas amostras, pico de retenção para padrão de difenoconazol. Concluindo-se que as feiras representam um ambiente adequado para patógenos humanos e indicadores, necessitando de uma maior higienização e treinamento dos comerciantes e consumidores de hortaliças do estado de Alagoas, principalmente em feiras convencionais, que apresentaram índices microbiológicos e parasitológicos mais críticos em relação a feiras com produtos agroecológicos; mas, a presença de difenoconazole em duas amostras de feiras agroecológicas sugerem contaminação acidental ou uso indiscriminado deste químico em produção da Lactuca sativa L., todavia os produtos de origem agroecológica representam uma melhor escolha para o consumidor.

Detection of enteroparasites in foliar vegetables commercialized in street- and supermarkets in Aparecida de Goiânia, Goiás, Brazil / Detecção de enteroparasitas em hortaliças comercializadas em feiras e supermercados em Aparecida de Goiânia, Goiás, Brasil

Foliar vegetables contaminated with fecal residues are an important route of transmission of intestinal parasites to humans. The aim of this study was to evaluate the presence of parasitic forms of protozoa and helminths on lettuces (Lactuca sativa) and collard greens (Brassica oleracea) sold in street- and supermarkets in the city of Aparecida de Goiânia, Goiás, Brazil. A total of 30 samples of each vegetable (15 samples from each supermarkets and street markets) was analyzed. All samples were processed by spontaneous sedimentation method and centrifugal flotation. In 45% of the samples, immature forms of intestinal parasites were identified with 66.7% helminths eggs and 33.3% protozoan cysts or oocysts. Significantly more lettuce samples were contaminated with eggs, cysts or oocyst of at least one parasite than collard green samples (U=216; Z=-3.45; P <0.001). The parasitic forms were identified morphologically up to the family level with eggs of Ancylostomatidae, Strongyloididae, Ascarididae and Taeniidae, or oocysts of Eimeriidae, to the genus with Cystoisospora sp. and Toxocara sp., and to the species level with Cystoisospora canis, Dipylidium caninum and Hymenolepis nana. The presence of these infective agents in lettuce and collard green from both street- and supermarkets highlights the high risk of spreading parasites by eating raw vegetables sold in Aparecida de Goiânia.

Hortaliças contaminadas com resíduos fecais são importantes vias de transmissão de parasitas intestinais ao homem. O objetivo deste estudo foi avaliar a presença de formas parasitárias de protozoários e helmintos em alface (Lactuca sativa) e couve (Brassica oleracea) vendidas em feiras e supermercados na cidade de Aparecida de Goiânia, Goiás, Brasil. Um total de 30 amostras de cada vegetal (15 amostras de supermercados e 15 de feiras livres) foi analisado. Todas as amostras foram processadas pelos métodos de sedimentação espontânea e centrífugo-flutuação. Em 45% das amostras foram identificadas formas imaturas de parasitas intestinais sendo 66,7% ovos de helmintos e 33,3% de cistos ou oocistos de protozoários. Significativamente, mais amostras de alface estavam contaminadas com ovos, cistos ou oocistos de pelo menos um parasita do que as amostras de couve (U = 216; Z = -3,45; P <0,001). As formas parasitárias foram identificadas morfologicamente ao nível de família com ovos de Ancylostomatidae, Strongyloididae, Ascarididae e Taeniidae ou oocistos de Eimeriidae, dos gêneros Cystoisospora sp. e Toxocara sp., e ao nível de espécies com Cystoisospora canis, Dipylidium caninum e Hymenolepis nana. A presença desses agentes infecciosos em alface e couve, provenientes tanto de feiras quanto de supermercados, ressalta o alto risco de veiculação de parasitas pela ingestão de hortaliças cruas comercializadas em Aparecida de Goiânia.

Identification and mapping of quantitative trait loci for resistance to Liriomyza trifolii in romaine lettuce cultivar 'Valmaine'.

Liriomyza trifolii (Diptera: Agromyzidae) is a leafminer that causes ruinous damage to many leafy vegetables including lettuce (Lactuca sativa L.) by stippling and tunneling the leaves. In this study, a population of 125 F3 families was developed from the intraspecific cross of 'Valmaine' (resistant) and 'Okeechobee' (susceptible) romaine cultivars for inheritance analysis and molecular mapping of the resistance loci controlling stippling damage. The experiments were conducted in an insectarium (controlled environment). Stippling damage proved to be heritable because the broad-sense heritability (H2) was 0.58. A segregation analysis suggested that a single dominant allele, Sd1 locus, controls resistance against L. trifolii. Furthermore, a quantitative trait loci (QTL) analysis identified one novel QTL, named Stippling on LG5 (qSTP5), flanked by two SNPs that were mapped to a 5.2 cM (8.5 Mb region) interval, explaining over 13% of the total phenotypic variance. Desirable allele for resistance to L. trifolii was derived from resistant cultivar Valmaine. Identification of SNPs closely linked to the QTL responsible for L. trifolii resistance should facilitate plant breeders to develop resistant romaine lettuce cultivars.

Zoonotic parasitic organisms on vegetables: Impact of production system characteristics on presence, prevalence on vegetables in northwestern Iran and washing methods for removal.

Fresh vegetables are essential components of a healthy and nutritious diet, but if consumed raw without proper washing and/or disinfection, can be important agents of transmission of enteric pathogens. This study aimed to determine the prevalence of zoonotic parasites on vegetables freshly harvested and "ready to eat" vegetables from greengrocers and markets in northwestern Iran. In addition, the effect of cropping system and season on contamination levels were assessed as well as the efficacy of washing procedures to remove parasites from the vegetables. A total of 2757 samples composed of field (n = 1, 600) and "ready to eat" (n = 1157) vegetables were analyzed. Vegetables included leek, parsley, basil, coriander, savory, mint, lettuce, cabbage, radish, dill, spinach, mushroom, carrot, tomato, cucumber and pumpkin. Normal physiological saline washings from 200 g samples were processed using standard parasitological techniques and examined microscopically. A total of 53.14% of vegetable samples obtained from different fields and 18.23% of "ready to eat" vegetables purchased from greengrocers and markets were contaminated with different parasitic organisms including; Entamoeba coli cysts, Giardia intestinalis cysts, Cryptosporidium parvum oocysts, Fasciola hepatica eggs, Dicrocoelium dendriticum eggs, Taenia spp. eggs, Hymenolepis nana eggs, Ancylostoma spp. eggs, Toxocara cati eggs, Toxocara canis eggs, Strongyloides stercoralis larvae, and Ascaris lumbricoides eggs. In both field and "ready to eat" vegetables, the highest parasitic contamination was observed in lettuce with a rate of 91.1% and 55.44%, respectively. The most common parasitic organism was Fasciola hepatica. A seasonal difference in contamination with parasitic organisms was found for field and "ready to eat" vegetables (P < 0.05). There was a significant difference in the recovery of parasitic organisms depending on the washing method with water and dishwashing liquid being the least effective. Proper washing of vegetables is imperative for a healthy diet as the results of this study showed the presence of zoonotic parasites from field and ready to eat vegetables in Iran.

Molecular diagnosis of the curly lettuce parasitic contamination from hydroponic cultivation from supermarkets.

The consumption of vegetables has increased in recent years due to the search for a healthier diet that is rich in fiber and has fewer calories. To assess the parasitic contamination of lettuce sold in markets, a survey of parasites was carried out from a supermarket chain in the city of Londrina, Paraná. A total of thirty samples of lettuce were purchased in the ten markets visited, three in each, of which ten were conventionally cultivated, ten were hydroponically cultivated, and ten were organically cultivated. All samples were analyzed using the sedimentation methods of Hoffman, Pons and Janer and the fluctuation method of Faust and colleagues and Willis with adaptations. In addition, the samples were subjected to DNA extraction by a commercial kit and polymerase chain reaction to detect Toxoplasma gondii, Cryptosporidium spp. and Giardia spp., which are protozoa that cause food and waterborne parasitic outbreaks. All samples were negative for sedimentation and flotation techniques. One of the hydroponically cultivated samples was positive for T. gondii. The results demonstrate the risk of curly lettuce contamination from hydroponic cultivation and the need for proper cleaning of these foods before consumption.

Ocorrência de enteroparasitas em alfaces (Lactuca sativa) comercializadas em mercados municipais em Rio Branco, Acre / Occurrence of enteroparasitas in alfaces (Lactuca sativa) commercialized in municipal markets in Rio Branco, Acre / Presencia de enteroparasitos en lechuga (Lactuca sativa) comercializados en mercados municipales de Rio Branco, Acre

As hortaliças folhosas são ricas em vitaminas, sais minerais e fibras alimentares, proporcionando importantes benefícios para a saúde, o que acaba atraindo os consumidores, que costumam ingeri-las na forma crua, ficando expostos à contaminação por enteroparasitas. O objetivo do trabalho foi verificar a possível presença de enteroparasitas em alfaces (Lactuca sativa) comercializadas em três mercados municipais de Rio Branco, Acre. Foram analisadas 26 amostras de alfaces, onde as folhas das alfaces foram lavadas, em uma solução contendo 250 mL de água destilada e cinco gotas de detergente. O líquido foi filtrado em gazes de oito dobras e deixado sedimentar por 24 horas, à temperatura ambiente. Após o tempo decorrido o sobrenadante foi descartado, foram preparadas lâminas, que foram analisadas ao microscópio óptico. Os resultados obtidos neste estudo evidenciaram contaminação em 96,2% do total de amostras de alfaces analisadas. As principais estruturas parasitárias encontradas foram: Ascaridia sp., Eimeria sp., Entamoeba coli, Entamoeba histolytica, Ancylostoma sp., Strongyloides stercoralis, Enterobius vermicularis, Dipylidium caninum, Trichuris trichiura, Diphillobothrium latum e Balantidium sp. O enteroparasita mais abundante foi Ascaridia sp., tendo sido encontrados 164 (430) exemplares nas amostras, representando 38,14% do total de enteroparasitas encontrados. Ascaridia sp. foi também o enteroparasita mais frequente, sendo encontrada em 42,3% do total de amostras analisadas. Nesse contexto, a ingestão de alfaces cruas, provenientes dos mercados municipais estudados, pode representar risco potencial para os consumidores, caso elas não sejam higienizadas corretamente. Isto demonstra a importância de uma boa limpeza e desinfecção das folhas de alface antes do consumo.(AU)

Leafy vegetalizes are reich in vitaminas, mineral and. deitar febres, providing important health benefits, which ends up attracting consumers, who usually eat them in the raw form, being exposed to contamination by enteroparasites. The objective of the study was to verify the possible presence of enteroparasites in lettuce (Lactuca sativa) sold in three municipal markets in Rio Branco, Acre. 26 samples of lettuce were analyzed, where the lettuce leaves were washed, in a solution containing 250 mL of distilled water and. five drops of detergent. The liquid was filtered through eight-fold gauze and. left to settle for 24 hours at room temperature. After the elapsed time, the supernatant was discarded, slides were prepared and. analyzed under an optical microscope. The results obtained in this study showed contamination in 96.2% of the total samples of lettuce analyzed. The main parasitic structures found were: Ascaridia sp., Eimeria sp., Entamoeba coli, Entamoeba histolytica, Ancylostoma sp., Strongyloides stercoralis, Enterobius vermicularis, Dipylidium caninum, Trichuris trichiura, Diphillobothrium latum e Balantidium sp. The most abundant enteroparasite was Ascaridia sp., 164 (430) specimens were found in the samples, representing 38.14% of the total enteroparasites found. Ascaridia sp. was also the most common enteroparasite, was found in 42.3% of the total samples analyzed. In this context, ingestion of raw lettuce from the municipal markets studied may pose a potential risk to consumers if they are not properly sanitized. This demonstrates the importance of good cleaning and disinfection of lettuce leaves before consumption.(AU)

Las verduras de hoja son ricas en vitaminas, minerales y fibras dietéticas, aportando importantes beneficios para la salud, lo que acaba atrayendo a los consumidores, que suelen consumirlas crudas, quedando expuestas a la contaminación por enteroparásitos. El objetivo del estudio fue verificar la posible presencia de enteroparásitos en lechugas (Lactuca sativa) vendidas en tres mercados municipales de Rio Branco, Acre. Se analizaron 26 muestras de lechuga, donde se lavaron las hojas de lechuga, en una solución que contenía 250 mL de agua destilada y cinco gotas de detergente. El líquido se filtró a través de una gasa de ocho veces y se dejó reposar durante 24 horas a temperatura ambiente. Transcurrido el tiempo, se descartó el sobrenadante, se prepararon los portaobjetos y se analizaron al microscopio óptico. Los resultados obtenidos en este estudio mostraron contaminación en el 96,2% del total de muestras de lechuga analizadas. Las principales estructuras parasitarias encontradas fueron: Ascaridia sp., Eimeria sp., Entamoeba coli, Entamoeba histolytica, Ancylostoma sp., Strongyloides stercoralis, Enterobius vermicularis, Dipylidium caninum, Trichuris trichiura, Diphillobothrium latum y Balantidium sp. El enteroparásito más abundante fue Ascaridia sp., Se encontraron 164 (430) ejemplares en las muestras, lo que representa el 38,14% del total de enteroparásitos encontrados. Ascaridia sp. también fue el enteroparásito más frecuente, encontrándose en el 42,3% del total de muestras analizadas. En este contexto, la ingesta de lechuga cruda, de los mercados municipales estudiados, puede representar un riesgo potencial para los consumidores, si no se higienizan adecuadamente. Esto demuestra la importancia de una buena limpieza y desinfección de las hojas de lechuga antes del consumo.(AU)

Host plant nutrient contents influence nutrient contents in Bradysia cellarum and Bradysia impatiens.

The chive maggot Bradysia cellarum and the fungus gnat B. impatiens are two primary root pests of plants, which can coexist on the same host plants and are the devastating pests on liliaceous crops and edible fungi. Their growth and development are affected by the nutrient contents of their host plants. In this study, we assessed the effects of different host plant nutrients on the nutrient contents of these two Bradysia species. The nutrients of the chive (Allium tuberosum Rottl. ex Spreng.), board bean (Vicia faba L.), lettuce (Lactuca sativa L. var. ramosa Hort.), cabbage (Brassica oleracea L.), wild cabbage (Brassica oleracea var. capitata rubra) and pepper (Capsicum annuum L.) roots were determined, and their effect on nutrient content of the two Bradysia species after feeding on the host plant for three continuous generations were evaluated. The results show that chive and B-bean contained higher levels of protein, free amino acid, soluble sugar and starch than others. As a result, the soluble sugar, fat and protein contents were significantly higher in both Bradysia species reared on chive and B-bean than on cabbage, lettuce, W-cabbage and pepper, suggesting nutritional preference of these insects. Based on our results, we concluded that the two Bradysia species displayed nutrient preference toward chive and B-bean, which provides a reference for understanding their host plant range and for control of the insect species via field crop rotations.

Prevalence of contamination by intestinal parasites in vegetables (Lactuca sativa L. and Coriandrum sativum L.) sold in markets in Belém, northern Brazil.

BACKGROUND: Previous studies have recorded a high prevalence of intestinal parasites in lettuce (Lactuca sativa L.) and coriander (Coriandrum sativum L.) destined for human consumption. This study determined the prevalence of contamination by intestinal parasites in these two plants sold in two street markets and two supermarkets in the city of Belém, northern Brazil. RESULTS: A total of 200 plant samples were analyzed (100 of each species). The samples were collected randomly between August and October 2018, examined by the spontaneous sedimentation method with two washes, and stored for 24 h. The analysis found that 89% (89/100) of the lettuce samples and 86% (86/100) of the coriander samples were contaminated. Polyparasitism was more frequent in lettuce, but monoparasitism predominated in the coriander. A total of 226 intestinal parasites were found in the lettuce, with a predominance of non-pathogenic parasites in the supermarket samples and more pathogenic parasites in the samples from street markets. In the coriander samples, 172 intestinal parasites were identified, with a predominance of pathogenic parasites in samples from both types of market. In the case of the protozoans, the most prevalent species was Endolimax nana, followed by Blastocystis hominis, in both vegetables. In the helminths, hookworms predominated in the lettuce, and Trichuris trichiura in the coriander. CONCLUSIONS: These results highlight the need for the monitoring of parasite contamination in vegetables destined for human consumption. Public health initiatives should include educational campaigns on the importance of disinfecting vegetables prior to consumption. © 2020 Society of Chemical Industry.

Análise microbiológica e parasitológica de alfaces in natura obtida de três cidades do interior de Mato Grosso do Sul – MS

Alimentar-se de forma segura e saudável nas últimas décadas pode ser um desafio para toda a população. Isso porque cada vez mais se busca ingerir alimentos de origem vegetal ou in natura. Entretanto, os procedimentos de higienização e controle de contaminantes precisam ser realizados de forma eficientes. Desta forma, o objetivo deste trabalho foi verificar a presença de contaminantes microbiológicos e parasitários em alfaces obtidos do cultivo tradicional e hidropônico de três cidades do interior de Mato Grosso do Sul. A maioria das amostras independente do tipo de cultivo apresentaram quantidades superiores aos limites estabelecidos pela Agência Nacional de Vigilância Sanitária quanto a presença de coliformes termotolerantes, entretanto, apenas uma das amostras obtidas (cultivo hidropônico) apresentou contaminantes parasitário (Strongyloides stercolaris). Os dados obtidos demonstram a importância do emprego de métodos de higienização por parte dos consumidores previamente ao consumo para evitar contaminantes advindos dessa fonte alimentar. Outro ponto interessante é que os procedimentos de controle higiênicosanitário devem ser empregados independentes da forma do cultivo das hortaliças adquiridas para consumo.

Eating safely and healthily in recent decades can be a challenge for the entire population. This is because more and more people are looking to eat foods of plant origin or fresh. However, the procedures for cleaning and controlling contaminants need to be carried out efficiently. Thus, the objective of this work was to verify the presence of microbiological and parasitic contaminants in lettuces obtained from the traditional and hydroponic cultivation of three cities in the interior of Mato Grosso do Sul. by the National Health Surveillance Agency regarding the presence of thermotolerant coliforms, however, only one of the samples obtained (hydroponic cultivation) presented parasitic contaminants (Strongyloides stercolaris). The data obtained demonstrate the importance of using hygiene methods by consumers prior to consumption to avoid contaminants from this food source. Another interesting point is that the hygienic-sanitary control procedures should be used regardless of the form of cultivation of vegetables purchased for consumption.

Prevalence of enteroparasites in vegetables marketed in the municipality of Conceição da Barra, Espírito Santo, Brazil.

OBJECTIVE: To monitor the frequency of enteroparasites in lettuce (Lactuca sativa) and parsley (Petrosolium sativum) samples, marketed in commercial buildings in the municipality of Conceição da Barra, Espírito Santo, Brazil. MATERIALS AND METHODS: Between August 2015 and July 2016, four different popular commercial buildings (fairs, markets and supermarkets) were selected as the largest vegetable suppliers in the municipality of Conceição da Barra, Espírito Santo. A total of 40 samples were analyzed using the modified spontaneous sedimentation method at the Laboratory of Parasitology and Hematology of Centro Universitário Norte do Espirito Santo, Universidade Federal do Espírito Santo. RESULTS: The most frequent organism in the study population were the commensal Entamoeba coli and the parasites E. histolytica/E.dispar, hookworm, Balantidium coli, Ascaris sp., Toxocara sp., Taenia sp. and Dipylidium sp. CONCLUSIONS: The results indicate a high degree of contamination of the vegetables, probably related to the precariousness of production, transportation and handling, making it necessary to adopt measures that guarantee the best quality of food and, consequently, better population health.

Prevalence of enteroparasites in vegetables marketed in the city of Jaguaré, Espírito Santo, Brazil.

OBJECTIVE: To monitor the frequency of enteroparasites in lettuce (Lactuca sativa) and parsley (Petrosolium sativum) samples, marketed in commercial buildings in the municipality of Jaguaré, Espírito Santo, Brazil. MATERIALS AND METHODS: Between August 2016 and July 2017, five different popular commercial buildings (markets, supermarkets and fairs) in the municipality of Jaguaré, considered the main local vegetable suppliers were selected. Throughout the research, 30 vegetable samples were randomly selected for parasitological analysis in 3 replicates for each commercial building under study. The obtained samples were analyzed by the modified spontaneous sedimentation method at the Laboratory of Parasitology and Hematology of Universidade Federal do Espírito Santo. RESULTS: Of the 30 samples analyzed, 83.3% were positive for parasitic contamination and the most common parasites were Hookworm, Balantidium coli, Isospora belli, Ascaris sp. and Entamoeba sp. CONCLUSIONS: The results indicate a high degree of contamination of the vegetables, probably related to the precariousness of production, transportation and handling, making it necessary to adopt measures that ensure the best quality of food and, consequently, better population health.

Evidence of viable Helicobacter pylori and other bacteria of public health interest associated with free-living amoebae in lettuce samples by next generation sequencing and other molecular techniques.

Vegetables are one of the sources from which Helicobacter pylori can be acquired. This bacterium infects >50% of the global population and is a recognized type I human carcinogen. H. pylori enters into the viable but non-culturable state when it is in the environment, and therefore the use of molecular techniques is much convenient for its detection. Free-living amoebae (FLA) are protozoans found in vegetables. They are transmission vehicles for amoeba-resistant bacteria, among which H. pylori is included. The aim of this study is to study the occurrence and viability of H. pylori from lettuce samples, H. pylori internalized into FLA and the microbiome of FLA isolated from these samples. Special focus was pointed to human pathogenic bacteria. H. pylori was not directly detected in any lettuce sample by means of molecular techniques and neither by culture. However, intra-amoebic H. pylori DNA was detected by means of PMA-qPCR in 55% of the samples and viable intra-amoebic H. pylori cells in 25% of the samples by means of DVC-FISH technique. When FLA microbiome was studied, 21 bacterial genera were part of FLA microbiome in all samples. Helicobacter genus was detected as part of the FLA microbiome in two samples. Other bacteria of public health interest such as Aeromonas sp., Arcobacter sp., Legionella sp., Mycobacterium sp., Pseudomonas sp. and Salmonella sp. were detected as part of FLA microbiome along the analysed samples. This study demonstrates for the first time that H. pylori is internalized as well as alive inside FLA isolated from vegetables. Moreover, this study shows that FLA promote H. pylori detection in environmental samples. In addition, as far as we are aware, this is the first study which studies the microbiome of FLA isolated from vegetables. Among the FLA microbiome, bacteria of public health interest were detected, pointing out that FLA are carriers of these pathogens which can reach humans and cause a public health concern.

Parasitological evaluation of lettuce served in school meals at a Federal State School in Rio de Janeiro, Brazil

The Brazilian "National School Lunch Program" (PNAE) must provide healthy food for students in public primary education. Thus, it is necessary to ensure both nutritional and parasitological quality, reducing health risks. Vegetables must be clean, presenting no parasites and larvae, according to Brazilian legislation. Lettuce (Lactuca sativa L.) is one of the favorite vegetables among students, and is eaten raw in salads. This paper aims to evaluate the parasitological quality of lettuce served in school lunches. 72 samples of leaf lettuce, 36 from conventional agriculture (CA) and 36 from family agriculture (FA), were analyzed. Half the samples in each group were sanitized by immersion in a sodium hypochlorite solution, with 2% active stabilized chlorine for 10 minutes (n=18/each) and half were not sanitized (n=18/each). Parasite load evaluation was performed by two methods in each subgroup: spontaneous sedimentation (SS) and sedimentation by centrifugation (SC). The parasite frequencies found were evaluated by the chi-squared test. Medically relevant parasites identified were helminths (Strongyloides stercoralis, Ascaris lumbricoides and Hookworms) as well as protozoa (Balantidium coli and Entamoeba coli). 44.6% of the FA samples presented some form of parasite by SS evaluation and 33.4% by SC evaluation; 66.7% of the CA samples presented parasites by SS evaluation, and 44.5% by SC evaluation. No significant differences were noted between the FA and CA groups in either technique. No parasites were found in any of the sanitized lettuces, regardless of the subgroup or technique applied. These results evidence the importance of adequate training and guidance for vegetable growers, food handlers as well as the general population regarding proper hygiene of lettuce leaves prior to consumption.

Molecular diagnosis of the curly lettuce parasitic contamination from hydroponic cultivation from supermarkets / Diagnóstico molecular da contaminação parasitária de alface crespa de cultivo hidropônico em supermercados

Abstract The consumption of vegetables has increased in recent years due to the search for a healthier diet that is rich in fiber and has fewer calories. To assess the parasitic contamination of lettuce sold in markets, a survey of parasites was carried out from a supermarket chain in the city of Londrina, Paraná. A total of thirty samples of lettuce were purchased in the ten markets visited, three in each, of which ten were conventionally cultivated, ten were hydroponically cultivated, and ten were organically cultivated. All samples were analyzed using the sedimentation methods of Hoffman, Pons and Janer and the fluctuation method of Faust and colleagues and Willis with adaptations. In addition, the samples were subjected to DNA extraction by a commercial kit and polymerase chain reaction to detect Toxoplasma gondii, Cryptosporidium spp. and Giardia spp., which are protozoa that cause food and waterborne parasitic outbreaks. All samples were negative for sedimentation and flotation techniques. One of the hydroponically cultivated samples was positive for T. gondii. The results demonstrate the risk of curly lettuce contamination from hydroponic cultivation and the need for proper cleaning of these foods before consumption.

Resumo O consumo de vegetais aumentou nos últimos anos devido à busca de uma dieta mais saudável, rica em fibras e com menos calorias. Para avaliar a contaminação parasitária de alface vendida nos mercados, foi realizado um levantamento de parasitas em vegetais folhosos de uma cadeia de supermercados da cidade de Londrina, Paraná. Um total de 30 amostras foram compradas nos dez mercados visitados, três em cada, dos quais dez foram convencionalmente cultivados, dez cultivados hidroponicamente e dez foram cultivados organicamente. Todas as amostras foram analisadas, usando-se os métodos de sedimentação de Hoffman, Pons e Janer e o método de flutuação de Faust e colaboradores e Willis com adaptações. Além disso, as amostras foram submetidas à extração de DNA por um kit comercial e reação em cadeia da polimerase (PCR) para detectar Toxoplasma gondii, Cryptosporidium spp. e Giardia spp., que são protozoários causadores de surtos transmitidos pela água e alimentos. Todas as amostras foram negativas para técnicas de sedimentação e flutuação. Uma das amostras cultivadas hidroponicamente foi positiva para T. gondii. Os resultados demonstram o risco de contaminação por alface crespa do cultivo hidropônico e a necessidade de limpeza adequada desses alimentos antes do consumo.

Soilborne Inoculum Density and Environmental Parameters Influence the Development of Pythium Stunt Caused by Pythium tracheiphilum in Head Lettuce Crops.

In Quebec muck soils, Pythium stunt (Pythium tracheiphilum Matta) is responsible for important yield losses in head lettuce crops each year, which can reach up to 50% in certain cases. Despite the significance of the disease, factors influencing its development remain poorly documented, and no disease risk indicators are available, which makes the development of management strategies difficult. Hence, growers systematically use chemical fungicides throughout the growing season to reduce crop losses. However, it is known that soilborne disease incidence or severity may be influenced by soil inoculum density and environmental parameters. Therefore, the objectives of this study were to investigate the influence of inoculum density on lettuce growth under controlled conditions and evaluate the influence of soil inoculum density, air temperature, relative humidity, and rainfall on disease incidence under field conditions. In particular, this study aims to develop accurate predictors for Pythium stunt incidence. Results showed that, under controlled environment, thresholds of inoculum density of 97 and 46 propagules per gram of dry soil were needed to reduce lettuce dry weight by one-half for cultivars Estival and Prestige, respectively. These results were confirmed under field conditions, where a soil inoculum density >132 propagules per gram of dry soil combined with air temperatures <18°C for the first 2 weeks and rain accumulation >64 mm for the first 3 weeks after transplanting accurately predicted disease incidence 79% of the time. These relationships improve understanding of seasonal Pythium stunt development and will provide useful tools to develop sustainable management strategies.

Anaerobic Soil Disinfestation to Manage Soilborne Diseases in Muck Soil Vegetable Production Systems.

Anaerobic soil disinfestation (ASD) was evaluated as a tool for managing the root-knot nematode Meloidogyne hapla in lettuce (Lactuca sativa) and clubroot disease, caused by Plasmodiophora brassicae, in mustard greens (Brassica juncea) produced on Ohio muck soils in Huron and Stark Counties. In two consecutive years of field trials, wheat bran (20.2 Mg ha-1), molasses (10.1 Mg ha-1), and wheat bran (20.2 Mg ha-1) plus molasses (10.1 Mg ha-1) were assessed as ASD carbon sources and compared with nonamended controls. Data were collected from plants grown in the field and from plants grown in field-treated soils in growth chamber-based post-ASD bioassays. Anaerobic conditions developed in ASD-treated soils in both trial years, as indicated by polyvinyl chloride pipes painted with an iron oxide paint. Soil pH did not decrease during ASD at the Huron County site of the mustard greens clubroot trials in either trial year but soil pH decreased significantly during ASD in Stark County soils treated with ASD with either wheat bran or wheat bran plus molasses compared with control soils in both trial years. Impacts of ASD on plant biomass were inconsistent in direct field measurements; however, significantly higher biomasses were observed in lettuce and mustard greens grown in bioassay soils collected from plots treated with ASD with wheat bran-based amendments compared with plants grown in soils from control plots. Based on direct field measurements and bioassays, the use of ASD with any carbon source led to significant reductions in root-knot nematode galling on lettuce compared with controls. Reductions in clubroot severity in mustard greens following ASD were less consistent; however, significant reductions in clubroot severity were observed in the field in one trial year and in both years of bioassays. The results of these studies indicate that ASD is a promising tool for managing soilborne diseases in muck soil vegetable production systems.

An Additional Asset for the FLOTAC Technique: Detection of Gastrointestinal Parasites in Vegetables.

INTRODUCTION: Gastrointestinal parasites are considered amongst the most important threats to veterinary and human health worldwide. The transmission of these parasitic diseases usually involves the accidental ingestion of oocysts, cysts, eggs, and larvae, whose detection is generally achieved by classical coproparasitological methods, based on sedimentation and/or flotation techniques. These procedures might be inefficient or display a low sensitivity when performed on food matrices. This study aimed to assess the value of the FLOTAC technique for the detection of different parasitic stages of gastrointestinal parasites of domestic animals in fresh lettuce. MATERIAL AND METHODS: Samples (n = 100) were purchased from public markets located in the metropolitan region of Recife (Brazil). RESULTS: A total of 79% scored positive for eggs and/or cysts of gastrointestinal parasites. Protozoa and nematodes were detected in 32% (32/100) and 64% (64/100) of samples, respectively, with cysts of the genus Entamoeba (32%) and eggs of nematodes of the order Strongylida (30%) being the most frequently diagnosed. CONCLUSIONS: The findings herein reported demonstrate that the FLOTAC technique can be successfully applied for recovering food-borne parasites of medical and veterinary concern in food matrices.

Avaliação da qualidade sanitária de alfaces americanas utilizadas na elaboração de lanches em franquias de fast-food / Evaluation of the sanitary quality of lettuce used in the elaboration of meals in fast-food franchises

A população brasileira realiza muitas refeições em franquias de fast-food e a alface é o vegetal mais utilizado nas preparações. O objetivo do trabalho foi avaliar a qualidade sanitária das alfaces minimamente processadas utilizadas nas franquias de fast-food instaladas em Goiânia. Foram coletadas três amostras de cinco redes diferentes, identificadas como A, B, C, D, e E, e encaminhadas para pesquisa de matéria estranha e análise microbiológica de Coliformes Termotolerantes (CF), Escherichia coli e Salmonella sp. Apenas as franquias A e B possuíam alfaces próprias para consumo. As amostras obtidas das franquias C, D e E apresentaram contagens de CF > 1100 NMP/g e presença de E. coli, assim como matéria estranha, como insetos e parasitas (Ascaris lumbricoides, Strongyloides stercoralis, Ancilostomídeos e Paramecium sp.).