GILBERTO CASADEI BAPTISTA2 RESUMO A bioatividade de dezoito produtos quími-cos utilizados no controle de pragas e doenças do tomateiro, sobre duas linhagens de Trichogramma pretiosum Riley, 1879 (L 9 =Alegre, ES e L 10 = Venda Nova do Imigrante, ES), nas gerações F 1 e F 2 , foi investigada em laboratório. Ovos de Anagasta kuehniella (Zeller) contendo o parasitóide em diferentes estágios de desenvolvimento (ovo-larva, pré-pupa e pupa) foram tratados por meio de imersão nas respectivas caldas químicas. Os inseticidas triflumuron, clorfluazuron, deltametrina, Bacillus thuringiensis, lambdacialotrina, teflubenzuron, acefato, pirimicarb e ciromazina, e os fungicidas benomil, iprodiona, clorotalonil e dimetomorf, independente da linhagem, não reduziram a longevidade das fêmeas de T. pretiosum da geração F 1. Os inseticidas abamectin, cartap, metamidofós e lambdacialotrina afetaram a razão sexual de indivíduos da geração F 1, e não reduziram a taxa de emergência de parasitóides da F 2 , independente do estágio de desenvolvimento e da origem da população de T. pretiosum. Parasitóides de Venda Nova do Imigrante, ES (L 10 ) mostraram-se mais susceptíveis que os de Alegre, ES (L 9 ) aos efeitos dos compostos avaliados. De modo geral, a fase de pupa de T. pretiosum, independente da população, apresentou maior tolerância aos produtos testados. Recomenda-se a realização de novos testes para outras populações desse parasitóide que serão utilizadas no controle de pragas, pois podem responder de forma diversa aos produtos fitossanitários avaliados. TERMOS PARA INDEXAÇÃO:Trichogramma, pesticidas, seletividade, tomate. BIOACTIVITY OF PESTICIDES USED IN TOMATO (Lycopersicon esculentum MILL.) CROP TO Trichogramma pretiosum Riley, 1879 (HYMENOPTERA: TRICHOGRAMMATIDAE) IN F 1 AND F 2 GENERATIONS ABSTRACTThe bioactivity of eighteen pesticides commonly used to pests and diseases control on tomato, in two strains of Trichogramma pretiosum Riley, 1879 (L 9 =Alegre, ES and L 10 = Venda Nova do Imigrante, ES, Brazil) in F 1 and F 2 generations, was evaluated under laboratory conditions. The bioassays were conducted in a climatic chamber at 25 2 o C, 60 10% RH and 14 hours of photophase. Eggs of Anagasta kuehniella (Zeller) containing the parasitoid in different phases of development (egg-larva, pre-pupa and pupa) were treated by immersion in aqueous dilutions of the products. The insecticides triflumuron, chlorfluazuron, deltamethrin, Bacillus thuringiensis, lambdacyalothrin, abamectin, cartap and methamidophos, did not decrease the longevity of females T. pretiosum in F 1 generation independently of the parasitoid strain. Abamectin, cartap, methamidophos and lambdacyalothrin affected the sexual ratio in F 1, and did not decrease the emergence of parasitoids in F 2 generation, independently of stage of development and origin. The L 10 strain was more susceptible to all pesticides as compared to L 9 . The pupal stage of T. pretiosum was more tolerant to the products, independently of its origin. It is recommended new tests with other strain...

Resíduos de Pirimifós-Metil em Milho, Milho Pipoca, em Alguns de seus Produtos Derivados e Ação noControle de Sitophilus zeamais Mots. (Coleoptera: Curculionidae)RESUMO -Foi avaliada a degradação/persistência dos resíduos do inseticida organofosforado pirimifós-metil em grãos e produtos derivados de milho (farelo, canjica e farinha de milho) e de milho pipoca (pipoca), bem como a ação residual do inseticida no controle do gorgulho do milho, Sitophilus zeamais Mots. Os grãos foram tratados com a concentração de 12 mg.kg -1 (ppm) de ingrediente ativo para controle do gorgulho. As amostras foram tomadas logo após o tratamento e também aos 15, 30, 60, 120 e 240 dias após o tratamento. A determinação quantitativa foi feita por cromatografia em fase gasosa, usando-se um detector fotométrico de chama. Para os estudos sobre a ação residual de pirimifós-metil, amostras de ambos os tipos de grãos foram tomadas aos 15 e 30 dias após o tratamento e subseqüentemente a intervalos mensais pelo período de um ano. Grãos tratados e não-tratados (testemunha) foram infestados com adultos do gorgulho. A mortalidade foi avaliada 15 dias após a exposição. Os resíduos de pirimifós-metil não foram persistentes em ambos os tipos de grãos nem nos seus produtos derivados. Os resíduos decresceram 5-8 vezes no farelo de milho e na pipoca. Na canjica e na farinha de milho eles foram estáveis, porém os níveis foram baixos. Resíduos maiores no farelo do que nos grãos estão relacionados com o maior teor de óleo no produto processado. O inseticida manteve-se eficiente contra a praga por todo período de observação (1 ano) para os dois tipos de grãos. PALAVRAS-CHAVE: Resíduo de agrotóxicos, degradação/persistência, gorgulho-do-milho, grãos armazenados ABSTRACT -The degradation/persistence of residues of the organophosphorus insecticide pirimiphosmethyl was determined in corn and popcorn grains and in some of their processed products such as grain, bran, hominy and corn flour from corn and prepared popcorn and grain from popcorn. The action of the insecticide on the control of the corn weevil, Sitophilus zeamais Mots., was also evaluated. The grains were treated with the concentration of 12 mg.kg -1 (ppm) a.i. pirimiphos-methyl for the control of the weevils. Samples were taken at zero, 15, 30, 60, 120 and 240 days after treatment. Quantitative measurements were made by gas chromatography, by using a flame photometric detector. For pirimiphos-methyl residual action studies, samples of both types of grain were taken at 15, 30 days after treatment and subsequently at monthly intervals up to one year. Treated and non-treated (control) grains were infested with weevil adults. Mortality was checked 15 days after exposure. Pirimiphos-methyl residues were not persistent in either types of grains or their processed products. Residues dropped 5-8-fold in corn bran and popcorn. They were stable in hominy and corn flour, but the concentration levels were low. Higher residues in corn bran than in grain are related to the higher oil content in that processed pro...

-Insect-pest mobility can infl uence insect susceptibility to the insecticides used to control them. The objective of this work was to evaluate the fl ight activity of Sitophilus oryzae (L) and Sitophilus zeamais Motsch populations reared on corn and wheat grains, and its relationship with insecticide susceptibility. Unsexed adult insects with ages between 10 and 20 days were placed on a plastic tray. A 40-watt incandescent light bulb was positioned at a 50 cm height relative to the tray. Flight activity was evaluated during 30 min. In the LC 50 estimation bioassays, the insects were exposed to dry residues of the organophosphorus insecticide fenitrothion and of the pyrethroid insecticide esfenvalerate on the internal surface of glass vials. Mortality was evaluated 24h after installation of the experiments. Sitophilus zeamais showed greater fl ight activity when compared with S. oryzae; likewise, insects reared on corn had greater fl ight activity than those reared on wheat. Sitophilus oryzae was less susceptible to the insecticides studied than S. zeamais. Adults reared on wheat were more susceptible to the insecticides than those reared on corn. This study demonstrates that the lower fl ight activity of S. oryzae is related to its greater tolerance to insecticides.

Among the pests that attack stored maize and wheat grain, Sitophilus oryzae (L.) and S. zeamais Motsch (Coleoptera: Curculionidae) are the most destructive. This paper is aimed at the study of the insecticidal effect and the residual action of organophosphate fenitrothion, pyrethroid esfenvalerate, and the mixture of both on S. oryzae and S. zeamais in stored maize and wheat. Grains were treated in order to obtain theoretical concentrations of 10 and/or 0.5 mg·kg −1 fenitrothion and esfenvalerate, respectively. The effectiveness experiments were installed as of 15, and 30 days, and subsequently at monthly intervals as of 12 months after grain treatment, or until mortality ceased in the plots. After mortality evaluation happened all individuals were eliminated, either dead or alive, and grains were kept for 60 days to assess the number of emerged progeny. The comparison of mortality curves of the pest species within each combination of grain type and insecticide showed significant differences. In general, the mortality of S. oryzae decreased faster than that of S. zeamais considering the grain type-insecticide combination. Esfenvalerate was ineffective in all combinations. Higher mortality of both species was observed on wheat grains treated with fenitrothion and fenitrothion + esfenvalerate mixture. Best results as to progeny control were obtained with fenitrothion and fenitrothion + esfenvalerate mixture. The factors that influenced the pest control are discussed in the present work.

O objetivo do presente estudo foi avaliar a degradação/persistência do inseticida piretróide deltametrina em grãos de trigo e em seus produtos processados, a saber: farelo, farinha branca, farinha integral e pão. Os grãos foram tratados de modo a alcançar a concentração teórica de 0,35 mg kg-1 do piretróide. As amostras foram tomadas a zero, 15, 30, 60 e 90 dias após a aplicação. Houve tendência de concentração do piretróide no farelo de trigo e um menor acúmulo nas farinhas, sendo que após o processo de cozimento do pão observou-se perda do inseticida.

Increasing horticultural production under protected cultivation requires more detailed studies about the occurence of pesticide residues, due to the special and peculiar environment under controlled conditions, in which some pests, that are of little concern in the field, become important. The insecticide acephate and its methamidophos metabolite residues were evaluated in greenhouse-grown tomatoes and compared to an open-field tomato crop. The treatments: (a) check; (b) one application of 75 g a.i. acephate.100 L-1 water; (c) one application of 150 g a.i.100 L-1 water; (d) four applications of 75 g a.i.100 L-1 water were evaluated. Fruit, leaf and soil samples were taken at (-1), zero, 1, 3, 7, 14, 21 days after the last or only application. The quantitative determinations were done by gas chromatography, using flame-photometric detector. The acephate and methamidophos residues in fruits harvested in the greenhouse and in the field were always below their respective maximum residue levels (MRL) during the whole sampling period. The metabolism of acephate into methamidophos was very low in fruits, especially important in leaves, but not well characterized in soil. Acephate residues were higher in the greenhouse than in the field, especially in leaves and soil, showing stability and persistence up to the 7-day-sampling after application.

The objectives of this study were to evaluate the residues of the insecticide carbosulfan and its carbofuran metabolites and 3-hydroxy-carbofuran in orange compartments (whole fruit, bagasse and juice) and comparison between the residual levels found in fruits with the maximum residue level and the safety interval established by the Brazilian legislation. Two field experiments were carried out, both with the following treatments: a-check; b-one application of 10 g of carbosulfan . 100 L-1 of water; c-one application with twice the rate applied in treatment b; d-four applications with the same rate applied in treatment b. Samples were taken at (-1), zero, 1, 3, 7, 14, 21 and 28 days after the last or unique application. The quantitative determinations were done by gas chromatography technique, using a nitrogen-phosphorus detector. The carbosulfan metabolism to its carbofuran metabolite was rapid (3 days), being both analytes concentrated in the bagasse (peel + flavedo + albedo). However, the metabolism of carbofuran to 3-hydroxy-carbofuran was of low intensity or this metabolite was quickly dissipated. Carbosulfan residues and its metabolites did not penetrate into the fruit, thus not contaminating the juice. The use of the pesticide was adequate, with respect to fruit consumption, in relation to the Brazilian legislation.

O conhecimento do comportamento de herbicidas é fundamental na avaliação de sua eficácia na agricultura e na compreensão do impacto ambiental causado por estes produtos químicos. A drenagem do solo pode influir no comportamento do herbicida pois pode atuar como fator modificador de sua mobilidade, transporte, arraste superficial e infiltração no solo e consequentemente, da contaminação de águas subterrâneas. A presente pesquisa teve por objetivo verificar o efeito de um sistema de drenagem subterrâneo sobre o arraste lateral, lixiviação e contaminação do lençol freático pelo herbicida trifluralina aplicado em pré-emergência na cultura do milho. Os resultados obtidos das avaliações efetuadas na superfície do solo, na profundidade de 0 - 15 cm e na água de drenagem permitiram concluir, principalmente, que a drenagem subterrânea funciona como redutor da lixiviação superficial do herbicida, diminuindo assim os riscos de contaminação ambiental.
The determination of the influence of environmental conditions on the fate of soil spray herbicides plays an important role in their efficiency in agriculture and for the understanding of the environmental impact caused by these chemical products. Soil drainage may influence the mobility, transport, surface movement and infiltration of pesticides through the soil profile and consequently their presence in groundwater. Therefore, the purpose of this work was to ascertain the effect of a soil drainage system on the surface and lateral movements, leaching and groundwater contamination by the herbicide trifluralin sprayed in pre-emergence conditions, for a corn crop. The results from residuals on soil surface, in the depth of 0-15 cm and in groundwater allowed the major conclusion that subsurface drainage reduces movement and leaching of the herbicide, decreasing risks of environmental contamination