D. M. F. Capalbo

Toxicological evaluation of genetically modified cotton (Bollgard®) and Dipel® WP on the non-target soil mite Scheloribates praeincisus (Acari: Oribatida)

Insecticides derived from the bacterium Bacillus thuringiensis (Bt) and plants genetically modified (GM) to express B.thuringiensis toxins are important alternatives for insect pest control worldwide. Risk assessment of B.thuringiensis toxins to non-target organisms has been extensively studied but few toxicological tests have considered soil invertebrates. Oribatid mites are one of the most diverse and abundant arthropod groups in the upper layers of soil and litter in natural and agricultural systems. These mites are exposed to the toxic compounds of GM crops or pesticides mainly when they feed on vegetal products incorporated in the soil. Although some effects of B. thuringiensis products on Acari have been reported, effects on oribatid mites are still unknown. This study investigated the effects of the ingestion of Bt cotton Bollgard® and of the B. thuringiensis commercial product Dipel® WP on the pantropical species Scheloribates praeincisus (Scheloribatidae). Ingestion of Bollgard and Dipel did not affect adult and immature survivorship and food consumption (estimated by number of fecal pellets produced daily) or developmental time of immature stages of S. praeincisus. These results indicate the safety of Bollgard and Dipel to S. praeincisus under field conditions where exposition is lower and other food sources besides leaves of Bt plants are available. The method for toxicological tests described here can be adapted to other species of Oribatida, consisting on a new option to risk assessment studies.

Solid-state fermentation of Bacillus thuringiensis tolworthi to control fall armyworm in maize

The well-known entomopathogenic bacterium Bacillus thuringiensis (Bt) produces a spore-crystal complex which is responsible for its biocide characteristic, and the bacterium can be obtained by fermentation, either in liquid or semi-solid substrates. This paper presents a successful way to achieve solid-state fermentation of active Bt var. tolworthi (Btt) against Spodoptera frugiperda (fall armyworm) in corn. More than 10 9

Bacillus thuringiensis: fermentation process and risk assessment: a short review

Several factors make the local production of Bacillus thuringiensis (Bt) highly appropriate for pest control in developing nations. Bt can be cheaply produced on a wide variety of low cost, organic substrates. Local production results in considerable savings in hard currency which otherwise would be spent on importation of chemical and biological insecticides. The use of Bt in Brazil has been limited in comparison with chemical insecticides. Although Bt is imported, some Brazilian researchers have been working on its development and production. Fermentation processes (submerged and semi-solid) were applied, using by-products from agro-industries. As the semi-solid fermentation process demonstrated to be interesting for Bt endotoxins production, it could be adopted for small scale local production. Although promising results had been achieved, national products have not been registered due to the absence of a specific legislation for biological products. Effective actions are being developed in order to solve this gap. Regardless of the biocontrol agents being considered atoxic and harmless to the environment, information related to direct and indirect effects of microbials are still insufficient in many cases. The risk analysis of the use of microbial control agents is of upmost importance nowadays, and is also discussed.

By Products from Food Industries: Utilization for Bioinsecticide Production

Agricultural residues and wastewaters from food, beverages and paper industries, are feasible substrates to produce microbial insecticides through Bacillus thuringiensis fermentations. These substrates are sources of carbon and nitrogen that are essential components to culture media composition. Since 1970 our research group are studying both the submerged (1) and semisolid fermentations (2) and two patents (3, 4) of the processes were developed. Corn steep liquor and sugar cane molasses were determined as the principal components of the culture media. This paper deals with the process, advantages and problems and the use of low cost raw material availlable in Brazil. The group intends to develop local technology to produce Bacillus thuringiensis, just to use against agricultural pests that are responsible to 40% losses in field, harvested and stored products. These losses cause price increments in the final product and contribute to the maximize hungry and poverty problems, in Brazil.

A Study of Stakeholder Views to Shape a Communication Strategy for GMO in Brazil.

This paper analyzes the view of stakeholders on genetically modified organisms (GMOs) and the implications of these views on communication strategies for agricultural biotechnology in Brazil. It identifies and describes common groups of attitudes toward GMOs using multivariate statistical analyses. The study then looks for patterns of association between the common attitude groups and the following variables: socioeconomic characteristics trust in institutions as information sources and familiarity with the Brazilian biosafety authority. The article contributes to the understanding of public awareness by highlighting how information sources, trust in institutions, and socioeconomic characteristics, such as age and occupational qualification, play important roles in defining patterns of attitudes toward GMOs. The paper also discusses the implications of this knowledge for the development of a communication strategy plan that would promote public awareness and stimulate a well-informed Brazilian public debate on biosafety.

The Importance of Bacillus thuringiensis in the Context of Genetically Modified Plants in Brazil

Sustainable agriculture requires alternative interventions for pest control and management. In this context the use of microorganisms pathogenic to pests has become even more studied and widespread, especially in the successful case of bioinsecticides based on Bacillus thuringiensis. With advances in recombinant DNA biotechnology, B. thuringiensis has continued to show its potential with the insertion of its insecticide-encoding genes into plants, which thus become resistant to a varied range of pest insects. These Bt plants, often containing multiple Bt genes, are commercially available. And today, after assessing biosafety in several countries around the world, they are adequate to control pests without significant harm to humans or to the environment. If the required safety conditions are maintained, a greater use of these plants is anticipated, guaranteeing an effective tool for an environmentally friendly agriculture.

Development of a Bioreactor for Semi-Solid Fermentation Purposes: Bacterial Insecticide Fermentation

The development of Bacillus thuringiensis to obtain bacterial insecticide was well studied in Brazil. In the submerged process it was studied in a 250-liter fermentor, that is semi-pilot size production, and offers the opportunity scale up to a commercial scale.

OBTENÇÃO DE BIOINSETICIDA À BASE DE Bacillus thuringiensis EM NOVOS MEIOS DE CULTURA

Quatro residuos da agroindustria, foram testados em seis combinacoes diferentes, como meios de cultura liquidos, na obtencao de esporos de Bacillus thuringiensis. Os resultados obtidos indicaram a viabilidade de utilizacao dos residuos testados, sendo concluido que a combinacao equilibrada de fontes de nitrogenio e sais minerais, associada a presenca de pequenas quantidades de carboidratos e essencial na obtencao de elevados rendimentos em esporos bacterianos. O acompanhamento da fermentacao atraves de analises de pH e absorbância do meio, mostrou correlacao com o desenvolvimento bacteriano, indicando esse parâmetros como eficientes na deteccao das etapas fermentativas.