Entomopathogenic fungi stand out in the biological control of several agriculturally important insects. Six isolates of Metarhizium anisopliae, Cordyceps javanica, Beauveria sp. and B. bassiana were screened to control Anthonomus grandis, Euschistus heros, Oebalus poecilus, O. ypsilongriseus and Thyanta perditor, important insect pests of soybean, cotton and rice. The bioassays were conducted in a completely randomized design, with four replications (10 insects/replication). Significant differences for virulence were observed between the tested fungal species and isolates. For A. grandis, the most virulent isolate was M. anisopliae BRM 2335, followed by Beauveria BRM 14527 and BRM 67744 [82.5 to 97.5 % of mortality; average lethal time (LT₅₀) of 5.9 to 7.8 days]. M. anisopliae BRM 2335 was also highly virulent to the four stink bug species (75 to 97.5 % of mortality; LT₅₀ of 5.2 to 9.7 days). For the stink bugs, Beauveria sp. BRM 67744 was infectious to O. poecilus (75 % of mortality), but failed to control E. heros (16.9 % of mortality). C. javanica BRM 27666 and BRM 14526 showed average virulence to the stink bugs and A. grandis (17.5 to 57.3 % of mortality; LT₅₀ of 6.0 to 9.7 days). M. anisopliae was consistently more virulent to the stink bugs than the other fungi. Therefore, M. anisopliae BRM 2335 was selected for further studies under screenhouse and field conditions to control A. grandis and other stink bug species, especially E. heros.

Cotton is the most important crop for fiber production worldwide. However, the cotton boll weevil (CBW) is an insect pest that causes significant economic losses in infested areas. Current control methods are costly, inefficient, and environmentally hazardous. Herein, we generated transgenic cotton lines expressing double-stranded RNA (dsRNA) molecules to trigger RNA interference-mediated gene silencing in CBW. Thus, we targeted three essential genes coding for chitin synthase 2, vitellogenin, and ecdysis-triggering hormone receptor. The stability of expressed dsRNAs was improved by designing a structured RNA based on a viroid genome architecture. We transformed cotton embryos by inserting a promoter-driven expression cassette that overexpressed the dsRNA into flower buds. The transgenic cotton plants were characterized, and positive PCR transformed events were detected with an average heritability of 80%. Expression of dsRNAs was confirmed in floral buds by RT-qPCR, and the T₁ cotton plant generation was challenged with fertilized CBW females. After 30 days, data showed high mortality (around 70%) in oviposited yolks. In adult insects fed on transgenic lines, chitin synthase II and vitellogenin showed reduced expression in larvae and adults, respectively. Developmental delays and abnormalities were also observed in these individuals. Our data remark on the potential of transgenic cotton based on a viroid-structured dsRNA to control CBW.

RESUMO Este artigo discute, à luz da Teoria Histórico-Cultural, o papel dos signos artísticos na educação estética. Enfatiza o conceito de signo, percepção estética, expressão, criação artística e desenvolvimento humano. Teórico-metodologicamente, dialoga com Vigotski e com duas pesquisadoras das artes: a primeira realizou entrevistas semiestruturadas com artistas profissionais, e a segunda organizou rodas de conversas, na escola, com crianças em idade alfabetização. A discussão teórico-prática efetivada no presente artigo permite pensar uma educação estética articulada ao conceito de signo artístico e indica possibilidades de organização das artes na educação, como educação estética, de maneira a potencializar o desenvolvimento humano cultural.

Este artigo discute o conceito de corpo e arte-performance enfatizando as experimentações realizadas na escola básica. Dialoga com GLUSBERG (1987), COHEN (2002), PEREIRA (2013) na perspectiva da arte-performance e seus desdobramentos para o campo da educação. Faz uso do método cartográfico de pesquisa-intervenção com ênfase no acompanhamento dos processos a partir da composição de um plano conceitual como destaca DELEUZE e GUATTARI (1997). Os resultados permitem pensar o conceito de corpo como signo e a performance enquanto arte experimental híbrida e anárquica que anuncia heterotopias inventivas e provoca transformações nas práticas pedagógicas de professores da escola básica.

The objective of this work was to evaluate the population dynamics of the burrower bug (Scaptocoris castanea) in an area with cotton (Gossypium hirsutum) cultivated after cover crops. The insects were counted in soil samples collected at 0-40 cm depth. Insect incidence was documented in 18 cover crops, alone or intercropped, in each plant stage. Rainfall distribution was compared with fluctuations in the burrower bug population. Crotalaria species have a suppressive effect on the insect population, whereas some grass species favor its increase. Rainfall distribution directly influences the insect population.