-We report the occurrence of natural enemies of Plutella xylostela (L.) in organically farmed kale in Pernambuco, Brazil. Seven natural enemies were observed parasitizing or preying on larvae and pupae of P. xylostella -three parasitoids: Cotesia plutellae Kurdjumov (Hym.: Braconidae), Conura pseudofulvovariegata (Becker) (Hym.: Chalcididae) and Tetrastichus howardi (Olliff) (Hym.: Eulophidae), and four predators: Cheiracanthium inclusum (Hentz) (Araneae: Miturgidae), Pheidole sp.Westwood (Hym.: Formicidae), nymphs and adults of Podisus nigrispinus (Dallas) (Hem.: Pentatomidae), and one unidentified species of solitary wasp. Beyond recording these natural enemies, data on predation of P. xylostella larvae in the field and laboratory by C. inclusum are presented.KEY WORDS: Natural biological control, Cotesia, Conura, Tetrastichus, Cheiracanthium, Podisus, PheidoleThe diamondback moth (DBM), Plutella xylostella (L.), is the most destructive pest of crucifers worldwide. The estimated average control cost for DBM is greater than one billion dollars per year (Talekar 1992, Haseeb et al 2004. Intensive insecticide use continues to be the primary method of control against P. xylostella (Barros et al 1993, França & Medeiros 1998, Cheng et al 2008. As a result of biological and behavioral traits of DBM (e.g., great ability to disperse, high fecundity and short life cycle) and conditions offered by the environmental sites (e.g., availability of various crucifers in neighbor fields and throughout the year), P. xylostella has been considered as difficult to control. Thus, use of biological control methods is important for the management of this pest, and augmentation of biological control agents already present is prominent because it has minimum or no cost to growers.In this work we report natural enemies of P. xylostella on an organic farm of kale crop (~90 days old) located in Chã Grande, Pernambuco State, Brazil (08 o 15'14.4''S and 35 o 30'0.3''W with an altitude of 505 m). To sample the natural enemies we exposed sentinel 3 rd -instar DBM larvae at the rate of 30 larvae per kale plant in the field. The exposure system consisted of 15 plants distributed along two transects marked in the study area. Selected plants were eight meters apart and distributed throughout the kale field. Eight out of 15 plants monitored were confined using cylindrical cages (50 cm diameter x 80 cm high) made with 4 mm mesh nylon fastened with wood sticks. Three days after infestation, all remaining DBM larvae were collected, and held for rearing until either an adult DBM or a parasitoid emerged. Predators observed directly preying on larvae or pupae in the field were noted.Because there were significantly fewer P. xylostella larvae recovered in the uncaged plants, and the caged plants excluded spiders and predatory wasps, a study was conducted in the field and in the laboratory to measure the predation rates of the spider species on DBM larvae. The spider species found preying upon DBM larvae in the field was identified as Cheiracanth...

-The objectives of this work were to study the insecticides espinosad, lambdacyhalothrin and monocrotophos on the control of Alabama argillacea (Hübner), the compatibility of these insecticides with the predatory stinkbug Podisus nigrispinus (Dallas), and the effects of the insecticides and acaricides methiocarb, pymetrozine, thiamethoxam, abamectin, diafenthiuron, dicofol and propargite on the predatory stinkbug behavior preying upon A. argillacea under field conditions. More than 90% of cotton leafworm control was obtained at the day 0 of application with all insecticides. Control of A. argillacea by lambdacyhalothrin (20 g a.i./ha) and monocrotophos (240 and 320 g a.i./ha) was observed up to day 3 after application; while spinosad (30 and 60 g a.i./ha) prolonged control up to day 5. Monocrotophos and lambdacyhalothrin were significantly more toxic to P. nigrispinus compared to spinosad. Toxicity of monocrotophos and lambdacyhalothrin to P. nigrispinus was evident up to day 3 after application. Survival of P. nigrispinus was affected by methiocarb, thiamethoxam, diafenthiuron, abamectin and sulfur one day after application and only under thiamethoxam treatment after three days. Pymetrozine, dicofol and propargite did not affect P. nigrispinus survival compared to untreated plants. Podisus nigrispinus at the day of application did not prey on A. argillacea under methiocarb treatment, and the predation rate was affected under thiamethoxam, abamectin, diafenthiuron and sulfur treatments at the day of application and after three days. The insecticides pymetrozine and spinosad, and the acaricides dicofol and propargite were compatible to P. nigrispinus and should be considered within a cotton pest management program.KEY WORDS: Integrated pest management, pymetrozine, spinosad, methiocarb, thiamethoxam.RESUMO -Os objetivos deste trabalho foram estudar a ação dos inseticidas espinosade, lambdacialotrina e monocrotofós no controle do curuquerê-do-algodoeiro Alabama argillacea (Hübner), sua compatibilidade com o percevejo predador Podisus nigrispinus (Dallas), e os efeitos dos inseticidas e acaricidas metiocarbe, pimetrozine, tiametoxam, abamectim, diafentiurom, dicofol e propargite na predação de A. argillacea por P. nigrispinus no campo. Inseticidas e concentrações utilizadas proporcionaram controle de A. argillacea acima de 90% no dia da aplicação. O controle de A. argillacea por lambdacialotrina (20 g i.a./ha) e monocrotofós (240 e 320 g i.a./ha) foi observado até três dias após aplicação, enquanto espinosade (30 e 60 g i.a./ha) prolongou o controle acima de 90% até cinco dias. Monocrotofós e lambdacialotrina foram significativamente mais tóxicos para P. nigrispinus comparado a espinosade. O efeito residual de monocrotofós e lambdacialotrina para P. nigrispinus foi evidente até três dias após a aplicação. A sobrevivência de P. nigrispinus foi afetada por metiocarbe, tiametoxam, diafentiurom, abamectim e enxofre após um dia, e apenas por tiametoxam após três dias da aplicação. Pimetrozine, dicofol e proparg...

The predaceous stinkbug Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae) feeds on plants as well as on arthropod prey. The question arises whether feeding on plants might expose the predator to systemic insecticide via ingestion of the active ingredient or its metabolites through plant sap of treated plants. This interaction was investigated with nectaried and nectariless cotton plants cropped in pots and treated with the systemic insecticide thiamethoxam at 0.5, 1.0 and 2.0 mg per plant as a root drench. Development of P. nigrispinus fed on prey and on treated nectaried and nectariless cotton plants and confined at 15, 30 and 45 days after insecticide application, and adult reproduction from nymphs caged 30 days after treatment were determined. Podisus nigrispinus life history traits were unaffected by the type of cotton plant, nectaried or nectariless, but were significantly affected by insecticide dose and time after application. Developmental time was extended and fresh adult body weight was reduced by feeding on prey and treated plants. Nymphs caged on treated plants with the highest thiamethoxam concentration at 15 days after application produced only 13.2% of adults. Females emerged from nymphs caged on both plants and at all thiamethoxam concentrations at day 30 after application presented similar reproductive characteristics, except for age of first oviposition, which was delayed on plants treated with the highest thiamethoxam concentration. Thiamethoxam at 0.5 mg per plant restrained tobacco whitefly, Bemisia tabaci Gennadius (Homoptera: Aleyrodidae) colonization only during the first 15 days after application to either cotton plant, and similar immature densities were sampled at day 35 after application on treated and untreated plants. However, plants treated with 1.0 and 2.0 mg per plant as a drench and cropped in pots were protected from tobacco whitefly for up to 45 days after exposure to a whitefly colony.

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