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.

Enzymatic comparison and mortality of Beauveria bassiana against cabbage caterpillar Pieris brassicae LINN

Abstract Beauveria bassiana, an entomopathogenic fungus, is the alternative biocontrol agent exploited against major economic crop pests. Pieris brassicae L. is an emerging pest of the Brassicaceae family. Therefore, in the present study, fungal isolates of Beauveria bassiana, viz. MTCC 2028, MTCC 4495, MTCC 6291, and NBAII-11, were evaluated for their virulence against third instar larvae of P. brassicae. Among all these fungal isolates, maximum mortality (86.66%) was recorded in B. bassiana MTCC 4495 at higher concentration of spores (109 conidia/ml), and the minimum mortality (30.00%) was recorded in B. bassiana MTCC 6291 at a lower concentration (107 conidia/ml) after ten days of treatment. The extracellular cuticle-degrading enzyme activities of fungal isolates were measured. Variability was observed both in the pattern of enzyme secretion and the level of enzyme activities among various fungal isolates. B. bassiana MTCC 4495 recorded the maximum mean chitinase (0.51 U/ml), protease (1.12 U/ml), and lipase activities (1.36 U/ml). The minimum mean chitinase and protease activities (0.37 and 0.91 U/ml, respectively) were recorded in B. bassiana MTCC 6291. The minimum mean lipase activity (1.04 U/ml) was recorded in B. bassiana NBAII-11. Our studies revealed B. bassiana MTCC 4495 as the most pathogenic isolate against P. brassicae, which also recorded maximum extracellular enzyme activities, suggesting the possible roles of extracellular enzymes in the pathogenicity of B. bassiana against P. brassicae.

Distribuição de ovos de Plutella xylostella (L. ) (Lepidoptera: Plutellidae) e o parasitismo por Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) / Egg distribution of Plutella xylostella (L. ) (Lepidoptera: Plutellidae) and the parasitism by Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae)

Oviposition site preference of Plutella xylostella (L.) and the parasitism by Trichogramma pretiosum Riley on cabbage plants at pre- and post-head formation were investigated in commercial cabbage field. Groups of six plants were randomly caged. In each cage three pairs of 24h-old P. xylostella moths were released, followed by 1,200 T. pretiosum females released 12h later. After 48h from parasitoid release, plants were harvested and fully inspected with the oviposition mapped according to the leaf position and their parts (basal, median and border) and upper and bellow leaf surfaces. Moth oviposition and egg parasitism were equally distributed across the plant leaves at the pre-head formation stage. At this stage, the basal part and the upper leaf surface were the preferred places for oviposition and egg parasitism, respectively. Cabbage plants at the post-head formation stage exhibited greater oviposition and egg parasitism in the inner leaf attached to the head. At this stage, the leaf border and the upper leaf surface were the preferred places for oviposition and egg parasitism, respectively. The infestation of P. xylostella on cabbage can be determined by egg counting at the pre- and post-head formation stages at the basal part of the leaves or at the border of the leaf attached to the head, respectively. And, in both plant stages parasitized eggs by T. pretiosum are more likely to be found at the upper leaf surface.

Biologia de Plutella xylostella L. (Lepidoptera: Plutellidae) em cultivaresde couve-flor / Biology of Plutella xylostella L. (Lepidoptera: Plutellidae) reared on cauliflower genotypes

This work was conducted to evaluate biological parameters of Plutella xylostella L. reared on leaves of several cauliflower genotypes under laboratory conditions. The experiment was set in a randomized block design and arranged in a 6 x 2 factorial (genotypes x generations). Leaf disks of the cultivars Barcelona, Verona, Piracicaba Precoce, Sharon, Silver Streak, and Teresópolis Gigante were placed in Petri dishes with 12 newly-hatched larvae. Leaf disks were initially changed after the fourth day, but daily afterwards until the larvae reached the pupal stage. The same procedure was adopted for the second generation. Twenty adults of each sex were separated from each genotype to evaluate their longevity, and 10 couples from each treatment were used to assess female fecundity. The lowest larval survival was obtained on the 'Silver Streak' (78.9 percent) and highest on 'Verona' (97.1 percent). The 'Silver Streak' and 'Teresópolis Gigante' showed the lowest pupal weights (4.83 mg and 5.11 mg, respectively), as well as the lowest fecundity, 119.4 and 123.0 eggs/female, respectively, while 'Piracicaba Precoce' the highest (167.7 eggs/female). Males obtained from larvae reared on 'Teresópolis Gigante' and 'Silver Streak' lived shorter (5.1 days), while the short-lived females were obtained from larvae reared on 'Barcelona' and 'Verona' (4.9 and 5.0 days). Insect development was prolonged in the second generation in all tested genotypes.

Primeiro registro de Lipaphis pseudobrassicae Davis (Hemiptera: Aphididae) e sua associação com insetos predadores, parasitóides e formigas em couve (Cruciferae) no Brasil / First record of Lipaphis pseudobrassicae Davis (Hemiptera: Aphididae) and its association with predator insects, parasitoids and ants in kale (Cruciferae) in Brazil

Este estudo descreve a fauna de insetos predadores, parasitóides e formigas associada a pulgões em couve (Brassica oleracea L. var. acephala D.C.), cultivada em sistema orgânico. O pulgão foi identificado como Lipaphis pseudobrassicae Davis, sendo este o primeiro registro da espécie atacando couve no Brasil. Parasitismo primário por Diaeretiella sp. e Aphidius sp. e hiperparasitismo por Aphydencyrtus sp., Alloxysta sp., Pachyneuron sp. e Syrphophagus sp. foram observados. Vinte espécies de Coccinellidae foram coletadas, sendo que oito delas foram observadas, tanto na fase adulta como larval, atacando o pulgão: Hyperaspis (Hyperaspis) festiva Mulsant, que foi a mais abundante (72,5 por cento do total de insetos predadores obtidos), Cycloneda sanguinea (L.), Eriopis connexa Germar, Coleomegilla maculata DeGeer, Hippodamia convergens Guérin, Heterodiomus sp., Scymnus (Pullus) sp.1 e Scymnus (Pullus) sp.2. Larvas de Syrphidae afidófagas coletadas nas folhas de couve infestadas por L. pseudobrassicae pertencem às espécies Allograpta exotica (Wiedemann) e Ocyptamus gastrostactus (Wiedemann). Larvas e pupas de Syrphidae foram parasitadas por Pachyneuron sp., Syrphophagus sp. e Diplazon laetatorius Fabricius. Larvas de Chrysopodes sp. foram observadas alimentando-se de L. pseudobrassicae. Espécies de formigas associadas às colônias desse pulgão foram Ectatomma quadridens Fabricius e Pheidole sp.

This study describes the fauna of predator insects, parasitoids and ants associated with aphids on kale (Brassica oleracea L. var. acephala D.C.) in organic system. The aphid was identified as Lipaphis pseudobrassicae Davis, and this is the first record of the species attacking kale in Brazil. Primary parasitism by Diaeretiella sp. and Aphidius sp. and hyperparasitism by Aphydencyrtus sp., Alloxysta sp., Pachyneuron sp. and Syrphophagus sp. were observed. Twenty species of Coccinellidae were collected, and eight of them were observed in adult and larval stages attacking the aphid: Hyperaspis (Hyperaspis) festiva Mulsant, which was the most abundant (72.5 percent of all predator insects obtained), Cycloneda sanguinea (L.), Eriopis connexa Germar, Coleomegilla maculata DeGeer, Hippodamia convergens Guérin, Heterodiomus sp., Scymnus (Pullus) sp.1 and Scymnus (Pullus) sp.2. Aphidophagous Syrphidae larvae collected on leaves of kale infested by L. pseudobrassicae belong to the species Allograpta exotica (Wiedemann) and Ocyptamus gastrostactus (Wiedemann). Larvae and pupae of Syrphidae were parasitized by Pachyneuron sp., Syrphophagus sp. and Diplazon laetatorius Fabricius. Larvae of Chrysopodes sp. were observed feeding on L. pseudobrassicae. Species of ants associated with the colony of this aphid were Ectatomma quadridens Fabricius and Pheidole sp.

Determinación del crecimiento de saccharornyces cerevisiae en agares formulados con extractos de desechos agroindustriales I / Determination of growth of saccharomyces cerevisiae in agars formulated with agroindustrial waste extracts I

Se utilizó saccharomyces cerevisiae para determinar cuantitativamente su crecimiento en agares formulados en base a extractos obtenidos de desechos de lactuca sativa (lechuga) y brassica oleracea (repollo), aserrín de pinus radiata, papel de diario de desecho y melaza como sustratos alternativos para el cultivo de esta levadura, con miras a la producción de proteínas unicelulares (SCP). Se prepararon los siguientes medios de cultivos: agar extracto vegetal (AFV), agar extracto aserrín (AFA), agar extracto papel (AEP) y agar extracto melaza (AEME), solos y suplementados con glucosa y NH4NO3. Estos se sembraron con diluciones de la levadura e incubaron por 48 h a 25ºC, tras lo cual se hizo el recuento de las colonias. Como control se utilizó agar extracto de malta al 2 porciento (AEM). El mayor recuento poblacional se registró en AEV (7.2x 105 ufc/ml). A los 10 días de incubación, se obtuvieron colonias de 5mm de diám. en AEV y solo puntiformes en AEP

Isolation of parasites on fruits and vegetables.

The current FDA method to recover parasites from fruits and vegetables is derived from procedures used to isolate parasitic protozoa from water. A 1kg portion of fruit or vegetable is divided into 200 g subportions. The subportions are sequentially processed in a sonic cleaning bath with 1.5 liters of detergent solution (1% sodium dodecyl sulfate, 0.1% Tween 80) and sonicated for 10 minutes. As each subsample is removed, it is thoroughly drained. After this sonic treatment, the wash water is collected in a polypropylene beaker, transferred to 50 ml polypropylene centrifuge tubes and centrifuged for 15 min at 1500 x g. The sediment is consolidated into one tube along with two rinsings of each tube. The final sediment is fixed in 4% formaldehyde for 10 minutes before examination for parasites. Indirect fluorescent antibody is applied to stain the parasites (Giardia spp. and/or Cryptosporidium spp.) by using commercial kits when available. If a large quantity of extraneous matter is contained in the sediment it may be reduced by layering on Sheather's fluid and centrifuging at 1500 x g for 15 minutes. The supernatant is collected and washed twice in distilled water. This procedure is adequate for protozoa and nonoperculate helminth eggs; operculate helminth eggs may be cleaned by extraction with ethyl acetate. When cabbage and lettuce were seeded at 1 organism/g, the rate of recovery for Cryptosporidium parvum with the FDA method was 1%. When cabbage was seeded at 1 egg/g and 10 eggs/g, the average rate of recovery of decorticated eggs of Ascaris sp. or untreated Trichuris sp. was 10%.(ABSTRACT TRUNCATED AT 250 WORDS)