Anderson Dionei Grützmacher

Monitoramento de agrotóxicos em dois mananciais hídricos no sul do Brasil

The objective of this study was to evaluate and to monitor the presence of pesticides in the waters of the Sao Goncalo channel and the Piratini river located in the southern region of the State of Rio Grande do Sul. During the rice growing season, water samples were collected five times, three samples from the river Piratini and four from the Sao Goncalo canal. The methodology used for the analysis of residues of quinclorac, carbofuran and clomazone was the High Performance Liquid Chromatography with Diode Array Detection (HPLC-DAD) and for residues of the pesticides fipronil and betacyfluthrin, the Gas Chromatography with Electron Capture Detection (GC-ECD) was used. Results show that from sowing to harvesting the quantity of pesticide residues in water decreased. It was also observed that, at the lowest point (Laranjal), a greater number of analyses contaminated with residues was detected (11 samples with some type of pesticide). Insecticide carbofuran and herbicide quinclorac were pesticides that presented residues more frequently (16 and 15 times, respectively). Clomazone and fipronil were present in each of the 7 samples with residues and betacyfluthrin was not detected at any site.

Seletividade de agrotóxicos usados na produção integrada de maçã para adultos de Trichogramma pretiosum

The objective of this work was to evaluate the side effects of 12 pesticides used in the integrated production of apple, in laboratory (25±1oC temperature, 70±10% relative humidity and 14 hours photophase), exposing adults of Trichogramma pretiosum to fresh dry pesticide film, in the maximum dosage recommended for field use, with subsequent assessement of the number of eggs parasitized per female. The reduction in the parasitism, compared with the control (water), was used to classify the pesticides as harmless ( 99%). The acaricides Envidor (spirodiclofen), Kendo 50 SC (fenpyroximate) and Ortus 50 SC (fenpyroximate), the fungicides Antracol 700 PM (propineb), Midas BR (famoxadone + mancozeb), Palisade (fluquinconazole), Persist SC (mancozeb) and Systhane PM (myclobutanil) and the insecticide Mimic 240 SC (tebufenozide) were harmless; the herbicide Polaris (glyphosate) was slightly harmful; the herbicides Finale (gluphosinate-ammonium) and Roundup Original (glyphosate) were moderately harmful to T. pretiosum.

Seletividade de formulações de glyphosate a Trichogramma pretiosum (Hymenoptera: Trichogrammatidae)

A study was carried out in the laboratory to investigate the side-effects reported in Brazil of eight glyphosate formulations (Roundup®, Roundup® WG, Roundup® Transorb, Polaris®, Gliz® 480 CS, Glifosato Nortox®, Glifosato 480 Agripec® and Zapp® Qi) on the egg parasitoid Trichogramma pretiosum (Hym., Trichogrammatidae). The experiments were carried out by exposing the adult parasitoids to fresh pesticide residues applied on glass plates at a concentration of 14.4 mg L-1 of acid equivalent of glyphosate. The control group was treated with distilled water. Eggs of the alternative host Anagasta kuehniella (Lep., Pyralidae) were offered to parasitism. The capacity of parasitism per T. pretiosum adult female and the reduction in capacity of parasitism compared with the control group were used to estimate toxicity of the product. The formulations were classified into four categories, according to parasitism reduction: 1, harmless ( 99%). The results showed that the side-effects of the glyphosate formulations were dependent on type of salt and that formulations with potassic salt (Zapp® Qi) and ammonium salt (Roundup® WG) were slightly harmful to T. pretiosum adults. The remaining formulations isopropylamine salt (Roundup®, Roundup Transorb®, Polaris®, Gliz® 480 SC, Glifosato Nortox®, Glifosato 480 Agripec®) were moderately harmful to T. pretiosum adults.

Seletividade de herbicidas registrados para a cultura do milho a adultos de Trichogramma pretiosum (Hymenoptera: Trichogrammatidae)

- Chemical control has been one of the most widely used methods for weed mana gement in corn. However, the use of herbicides can cause adverse effects on beneficial insects, such as egg parasitoids. Thus, this work aimed to evaluate the selectivity of 12 herbicides regis tered for corn at the immature stages of Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae) under laboratory conditions (temperature 25±1 o C, relative humidity 70±10%; photoperiod 14 hours). The herbicides were diluted in a proportion of 200 L of water per hectare and sprayed on lepidopteran eggs containing immature forms of the parasitoids, at the egg-larva, prepupae and pupae stages. The emergence percentage of parasitoids was evaluated, and, when compared with the control, the herbicides were classified as harmless (class 1, 99%). The herbicides Agrisato 480 SL, Finale, Glifos, Glifosato Nortox, Gliz 480 SL, Polaris, Roundup Original, Roundup Transorb, Roundup WG, Trop and Zapp Qi were classified as harmless (class 1) at different immature stages of T. pretiosum, and considered selective to the parasitoid. Although harmless at the egg larva and prepupae stages, Gramoxone 200 was classified as slightly harmful (class 2) at the pupae stage. Accordingly, to better reconcile the che mical management of weeds with the biological control of insects, the use of herbicides allowing greater survival of T. pretiosum is suggested, whenever possible.

Consumo e Utilização de Alimento por Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) Originária de Diferentes Regiões do Rio Grande do Sul, das Culturas do Milho e do Arroz Irrigado

The goal of this work was to determine by means of consumption and utilization of natural food, the existence of strains of Spodoptera frugiperda (J.E. Smith)in different areas of corn and irrigated rice in Rio Grande do Sul. Four populations were collected: one in Santa Rosa, traditional area of corn cropping; one in Uruguaiana, traditional area of rice; and two in Pelotas, where corn and rice are planted side by side. In the laboratory, 20 larvae were individualized (second generation) and kept in petri dishes, in BOD, at 25oC temperature, 70 ± 10% RH and 14h photophase. The larvae were fed on leaves of their respective hosts, hybrid of corn BRS 8330 and the cultivar of irrigated rice Embrapa 6-Chui. The leaves of both hosts were submitted to bromatological analysis. The dry weight of the larva at maximum development, food consumed and feces eliminated were determined and the nutritional ratios were calculated: relative consumption ratio (RCR), relative metabolic ratio (RMR), relative growth ratio (RGR), approximate digestibilidade (AD), efficiency of conversion of ingested food (ECI), efficiency of conversion of digested food (ECD) and the metabolic cost (100 - ECD). Rice was more suitable as food for S. frugiperda; it was ingested in smaller amount, presented smaller 100 - ECD and larger ECI and ECD. A strong possibility of existence of two strains of S. frugiperda is evidenced in the State of Rio Grande do Sul, the corn and rice strains, which are morphologically similar but physiologically different.

Isca tóxica e disrupção sexual no controle da mosca-da-fruta sul-americana e da mariposa-oriental em pessegueiro

The objective of this work was to evaluate the simultaneous use of toxic bait and mating disruption technique using sexual pheromone for Anastrepha fraterculus and Grapholita molesta control, in commercial peach orchards. Three 0.5-ha orchards were used, with the following treatments: orchad 1, toxic bait (Biofruit 3% + Malathion 500 CE, 200 mL in 100 L) and mating disruption using sexual pheromone (Splat Grafo) in 1,000 points ha-1; orchad 2, conventional management, using contact insecticides 2 to 3 times a year; orchad 3, no pest control. Adult populations of both species, and sprout and fruit damages were monitored during the 2007/2008 and 2008/2009 crop seasons. Simultaneous use of toxic bait and mating disruption technique decreased the captures of A. fraterculus and G. molesta in more than 90%. In the two crop seasons, the damages on sprouts decreased 62-85%, and 98-99% on fruit, compared to the untreated orchard.

Ação de produtos naturais sobre a sobrevivência de Argyrotaenia sphaleropa (Meyrick) (Lepidoptera: Tortricidae) e seletividade de inseticidas utilizados na produção orgânica de videira sobre Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae)

This work was conducted to study the effect of commercial formulations of insecticides with emphasis on that allowed in the organic production (neem, natural piretro and pirolenhoso extract) to control Argyrotaenia sphaleropa (Meyrick) (Lepidoptera: Tortricidae) and their performance on the egg parasitoid Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) adults. The insecticides Natuneem® (1500ppm of azadirachtin L-1) and the pirolenhoso extract (Biopirol 7 M®) (250 and 500mL 100L-1) were not efficient in the control of A. sphaleropa when applied over grapevine leaves (Vitis sp.) cultivate Chardonnay. Natural piretro (250 and 500mL 100L-1) resulted in a mortality of 77.65 and 85.88% of insects, respectively 120 hours after application. The secondary effect of insecticides allowed was evaluated on adults of the egg parasitoid T. pretiosum following International Organization for Biological and Integrated Control (IOBC) methodology. It was observed that Natuneem® (500mL 100L-1), Biopirol 7 M® (500mL 100L-1) and Dipel DF® (100g 100L-1) had been innocuous (<30% parasitism reduction) while natural piretro (250mL 100L-1) was classified as moderately harmful (80-99% of parasitism reduction). Natural piretro in the higher dose (500mL 100L-1) showed a parasitism reduction in more than 99% in the same way that the pattern Lebaycid 500® (100mL 100 L-1).

Manejo de pragas e doenças na produção integrada e convencional de pêssegos

A Producao Integrada de Pessego (PIP) esta sendo desenvolvida na regiao de Pelotas-RS, desde o ano de 1999, com o objetivo de avaliar, agronomicamente, o sistema de Producao Integrada (PI) comparado com o sistema de Producao Convencional (PC), em pomar de pessegueiro cv. Diamante. Foram analisados os dados de cinco safras (1999-2003), onde as avaliacoes compreenderam danos causados por pragas: grafolita, mosca-das-frutas, gorgulho e cochonilha; ocorrencia de doencas: podridao-parda, bacteriose, sarna e outras doencas; e numero de aplicacoes de agrotoxicos. Os danos por grafolita foram de 1,11% e de 1,69%, para os sistemas PI e PC, respectivamente. Os danos decorrentes do ataque pelo gorgulho do milho foram de 2,12% na PI e 0,86% na PC. No sistema PI, o percentual de frutas com podridao-parda foi de 26,27% e na PC foi de 30,55%, sendo a maior causa das perdas nos pomares. A ocorrencia de sarna foi muito elevada na area com PC, no ano de 2003, atingindo 33,82% dos frutos analisados. O numero de tratamentos fitossanitarios foi maior na PC, em 1999 e 2000 e, posteriormente, houve similaridade nos tratamentos efetuados nos dois sistemas PI e PC. A avaliacao conjunta dos resultados demonstra uma superacao do sistema PI, quando comparado com o sistema PC, nos parâmetros analisados, indicando que e possivel conduzir os pomares de pessegueiro de acordo com as Normas de Producao Integrada de Pessego.

Biologia e exigências térmicas de Spodoptera cosmioides (Walk.) (Lepidoptera: Noctuidae)

O objetivo do trabalho foi estudar a biologia de Spodoptera cosmioides (Walk.) em diferentes temperaturas e determinar suas exigencias termicas, visando fornecer subsidios para a criacao do inseto em laboratorio. Para isso, os periodos embrionario e pos-embrionario foram avaliados em sete temperaturas (14, 18, 22, 25, 28, 30 e 32oC), em câmaras climatizadas, com fotofase de 14h. As lagartas foram criadas em dieta artificial, tendo como fontes proteicas feijao branco, farelo de soja, levedura de cerveja, germe de trigo e leite em po. A duracao do periodo embrionario decresceu com o aumento da temperatura na faixa de 14°C a 25°C, mantendo-se constante entre 28°C e 32°C. Para os demais estagios (lagarta, pre-pupa e pupa), foi observada uma relacao inversa entre a temperatura e a duracao na faixa de 14°C a 30°C, estendendo-se a 32°C para pupas. A duracao da fase de pupa dos machos foi maior do que das femeas, o que promoveu assincronia na emergencia de adultos. As temperaturas bases do periodo embrionario, fase de larva, pre-pupa, pupa e ciclo total foram 9,34°C; 11,65°C; 9,65°C; 11,08°C e 11,23oC, com constantes termicas de 62,73 graus-dia (GD); 254,61 GD; 33,42 GD; 177,55 GD e 525,11 GD, respectivamente. Avaliando-se, separadamente, a fase de pupa, as temperaturas bases foram 11,25°C para machos e 10,81oC para femeas, com constantes termicas de 188,26 GD para machos e 165,47 GD para femeas. Para o ciclo total, a temperatura base e a constante termica para machos foram 11,28°C e 535,85 GD. Para as femeas, estas mesmas variaveis foram 11,15°C e 513,17 GD. Concluiu-se que a faixa de temperatura mais adequada para o desenvolvimento de S. cosmioides situa-se entre 25oC e 28oC, na qual pode-se obter de 9,6 a 11,7 geracoes anuais do inseto, em condicoes de laboratorio.

Susceptibilidade de adultos de Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) a fungicidas utilizados no controle de doenças da macieira

This study evaluated the susceptibility under laboratory conditions of Trichogramma pretiosum Riley adults to fungicides recommended by the Integrated Production of Apple (IPA). The bioassays were carried out using the International Organization for Biological Control (IOBC), West Palearctic Regional Section (WPRS) standard protocols. Twelve selected fungicides were studied in the doses (g or ml active ingredient/100 L) captan 1 (0.115), captan 2 (0.120), kresoxim-methyl (0.010), sulphur 1 (AG) (0.480), sulphur 2 (0.480), folpet (0.105), mancozeb (0.160), pyraclostrobin (0.010), tebuconazole (0.010), tetraconazole (0.005), thiophanate-methyl (0.050) and triforine (0.024). Distilled water was used as the blank treatment and the insecticide triclorfon (0.150) as a positive control. The parasitoids were exposed to dry residues applied on glass plates. The reduction in the capacity of parasitism was used to measure the effect of the chemical in comparison to the blank treatment. Each treatment was replicated four times. The results allowed us to classify the fungicides tested in four categories: 1, harmless ( 99%). 75% of the tested substances were classified as selective (classes 1 and 2) to the parasitoid. The fungicides captan 1, captan 2, kresoxim-methyl, folpet, pyraclostrobin, tebuconazole, thiophanate-methyl and triforine were harmless; mancozeb was slightly harmful; sulphur 1 (AG) and tetraconazole were moderately harmful and sulphur 2 was harmful. These findings should be taken into account when selecting fungicides to spray apple orchards against fungi diseases to preserve the egg parasitoid T. pretiosum.