Current situation of pests targeted by Bt crops in Latin America

Transgenic crops producing Bacillus thuringiensis- (Bt) insecticidal proteins (Bt crops) have provided useful pest management tools to growers for the past 20 years. Planting Bt crops has reduced the use of synthetic insecticides on cotton, maize and soybean fields in 11 countries throughout Latin America. One of the threats that could jeopardize the sustainability of Bt crops is the development of resistance by targeted pests. Governments of many countries require vigilance in measuring changes in Bt-susceptibility in order to proactively implement corrective measures before Bt-resistance is widespread, thus prolonging the usefulness of Bt crops. A pragmatic approach to obtain information on the effectiveness of Bt-crops is directly asking growers, crop consultants and academics about Bt-resistance problems in agricultural fields, first-hand information that not necessarily relies on susceptibility screens performed in laboratories. This type of information is presented in this report. Problematic pests of cotton and soybeans in five Latin American countries currently are effectively controlled by Bt crops. Growers that plant conventional (non-Bt) cotton or soybeans have to spray synthetic insecticides against multiple pests that otherwise are controlled by these Bt crops. A similar situation has been observed in six Latin American countries where Bt maize is planted. No synthetic insecticide applications are used to control corn pests because they are controlled by Bt maize, with the exception of Spodoptera frugiperda. While this insect in some countries is still effectively controlled by Bt maize, in others resistance has evolved and necessitates supplemental insecticide applications and/or the use of Bt maize cultivars that express multiple Bt proteins. Partial control of S. frugiperda in certain countries is due to its natural tolerance to the Bt bacterium. Of the 31 pests targeted and controlled by Bt crops in Latin America, only S. frugiperda has shown tolerance to certain Bt proteins in growers' fields, the most reliable indication of the status of Bt-susceptibility in most of the American continent.Fil: Blanco, C.A.. University of New Mexico; Estados UnidosFil: Chiaravalle, W.. Ento Agro; UruguayFil: Dalla Rizza, M.. INIA; UruguayFil: Farias, J. R.. Instituto Phytus; BrasilFil: García Degano, M. F.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Tecnología Agroindustrial del Noroeste Argentino. Provincia de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial "Obispo Colombres"(p). Instituto de Tecnología Agroindustrial del Noroeste Argentino; ArgentinaFil: Gastaminza, Gerardo Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Tecnología Agroindustrial del Noroeste Argentino. Provincia de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial "Obispo Colombres"(p). Instituto de Tecnología Agroindustrial del Noroeste Argentino; ArgentinaFil: Mota Sánchez, D.. Michigan State University; Estados UnidosFil: Murúa, María Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Tecnología Agroindustrial del Noroeste Argentino. Provincia de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial "Obispo Colombres"(p). Instituto de Tecnología Agroindustrial del Noroeste Argentino; ArgentinaFil: Omoto, C.. Universidade de Sao Paulo; BrasilFil: Pieralisi, B. K.. 260 Longswitch Road; Estados UnidosFil: Rodríguez, J.. Centro Internacional de Agricultura Tropical; ColombiaFil: Rodríguez Maciel, J. C.. Colegio de Postgraduados; MéxicoFil: Terán Santofimio, H.. Pioneer HiBreed; Estados UnidosFil: Terán Vargas, A.P.. Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias; MéxicoFil: Valencia, S. J.. Centro Internacional de Agricultura Tropical; ColombiaFil: Willink, Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Tecnología Agroindustrial del Noroeste Argentino. Provincia de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial "Obispo Colombres"(p). Instituto de Tecnología Agroindustrial del Noroeste Argentino; Argentin

An introduction to software verification with Whiley

This tutorial introduces the basic ideas of software specification and verification, which are important techniques for assuring the quality of software and eliminating common kinds of errors such as buffer overflow. The tutorial takes a practical hands-on approach using the Whiley language and its verifying compiler. This verifying compiler uses an automated proof engine to try to prove that the code will execute without errors and will satisfy its specifications. Each section of the tutorial includes exercises that can be checked using the online Whiley Labs website