ABSTRACT:The boll weevil colonizes cotton fields as early as cotton squaring, causing significant losses due to feeding and protected development inside fruiting structures throughout crop phenology. Successful control depends on control of adults and their accurate detection when they colonize the crops. The commercial trap and boll weevil attract-and-control tubes (BWACT) are the only available tools to monitor and attract-and-kill boll weevil, despite limitation in efficacy, and insecticide in BWACT is not allowed in organic production. A grandlure-and-glue reusable and insecticide-free tube (GGT) made with polyvinyl chloride tube, smeared with entomological glue, and lured with pheromone was tested to detect boll weevil activity across various seasons. Boll weevil showed activity during growing season and off-season from 2009 to 2012 in the Semiarid and with higher numbers captured in GGT in comparisons to commercial traps. GGT was able to detect early weevils in the field right after planting. Further, the overall averages resulted in 34-, 16.8-, and 7.5-times more weevils captured in GGTs compared to the traps during stalk destruction in the Semiarid 2011 and Cerrado season 2012/13 and during the harvesting period in the Cerrado season 2011/12, respectively. Therefore, boll weevils were captured actively during season and off-season and early captures obtained in GGT compared to traps showed a better correlation between captures and square damage.

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ResumoO uso simultâneo de diferentes métodos de controle é fundamental para o sucesso no manejo de pragas. Esse estudo investigou o efeito de aplicações do caulim nas populações de predadores residentes no dossel do algodoeiro e no parasitismo do bicudo em estruturas coletadas do solo em campo e, em botões florais em laboratório. A abundância de predadores residentes no dossel das plantas incluindo Araneae, Formicidae, Chrysopidae e Coccinellidae foi similar entre as áreas tratadas e não tratadas com o caulim, bem como a emergência dos parasitoides Bracon vulgaris Ashmead (Hymenoptera: Braconidae) e Catolaccus grandis Burks (Hymenoptera: Pteromalidae) oriundos de estruturas coletadas no solo em ambas as áreas. Da mesma forma, o parasitismo do bicudo em botões tratados e não tratados com caulim foi semelhante quando foram oferecidos ao parasitoide B. vulgaris em testes com chance de escolha. Sendo assim, os resultados mostram que aplicações do caulim não afetam o controle biológico natural por parasitoides associados ao bicudo e lagarta rosada e predadores residentes no algodoeiro. Palavras-chave: Controle físico, controle biológico, Anthonomus grandis e Pectinophora gossypiella AbstractSimultaneous use of control methods is essential to reach success in managing arthropod pests. The current study investigated the effect of kaolin application on resident predators in the cotton plant canopy and parasitism of boll weevil on abscised squares in the field, and parasitism of boll weevil in the laboratory. Predators Araneae, Formicidae, Chrysopidae, and Coccinellidae showed similar seasonal densities for kaolin-treated and untreated cotton fields as well as the emergence rate of the parasitoids Bracon vulgaris Ashmead (Hymenoptera: Braconidae) and Catolaccus grandis Burks (Hymenoptera: Pteromalidae) from abscised field-collected structures. Under laboratory conditions, the parasitism of boll weevil larvae infesting squares was similar when treated and untreated squares with kaolin were offered to the parasitoid under free choice test. Therefore, the results show that spraying cotton fields with kaolin does not affect the natural biological control by parasitoids of boll weevil and pink bollworm and resident predators naturally occurring in cotton fields.

ABSTRACT. The cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae), is a key pest of cotton, irrespective of the use of conventional or organic management. In organic systems, however, the use of synthetic insecticides is not allowed, increasing the difficulty of controlling this pest. This work evaluated aphid control and the ability of products to prevent aphid infestation using natural insecticides compared to a standard synthetic insecticide. The control trial was conducted with four products [Beauveria bassiana (Boveril ® ), neem oil (Neemseto ® ), and cotton seed oil compared to thiamethoxam (Actara ® )], and untreated plants served as the control group. The trial testing the efficacy of these products in preventing aphid infestation was conducted using the same products, excluding Boveril ® . The evaluations were conducted 72 and 120h post-treatment for the efficacy and the protection against colonization trials, respectively. The aphid control by cotton seed oil, Neemseto ® , and thiamethoxam was similar, with 100% control being achieved on the thiamethoxam-treated plants. Regarding the plant protection against aphid colonization, the insecticide thiamethoxam exhibited a better performance compared to the other tested products with steady results over the evaluation period. The natural products exhibited variable results with low protection against plant colonization throughout the evaluation period.Keywords: Insecta, organic cotton, cotton aphid, alternative control, population growth rate.Controle e proteção de plantas de algodão com inseticidas naturais contra a colonização de Aphis gossypii Glover (Hemiptera: Aphididae) RESUMO. O pulgão Aphis gossypii Glover (Hemiptera: Aphididae) é uma importante praga do algodoeiro, independente do sistema de cultivo convencional ou orgânico. Entretanto, no cultivo orgânico não é permitido a utilização de inseticidas sintéticos, o que dificulta o controle desta praga. Assim, avaliou-se o controle e a proteção da planta à infestação pelo pulgão com inseticidas permitidos em cultivo orgânico. O experimento de controle empregou três inseticidas naturais [Beauveria bassiana (Boveril ® ), óleo de nim (Neemseto ® ) e óleo de algodão comparado ao inseticida sintético tiametoxam (Actara ® )]. O experimento visando a proteção da planta à infestação foi conduzido com os mesmos inseticidas exceto o Boveril ® . As avaliações foram realizadas após 72 e 120h para os experimentos de controle e de proteção da planta, respectivamente. O controle do pulgão 72h após a aplicação foi similar entre óleo de algodão, Neemseto ® e Actara ® e atingiu 100% de controle com o Actara ® . Em relação à proteção da planta contra a colonização, o Actara ® destacou-se com maior proteção das plantas quando comparado aos demais inseticidas, sendo a eficiência mantida em todos os intervalos de avaliação. Já os demais tratamentos apresentaram variabilidade com relação à proteção ao longo dos intervalos de avaliação.Palavras-chave: Insecta, algodão orgânico, pulgão do algodoeiro, controle alternati...