Aplicações da biodiversidade bacteriana do solo para a sustentabilidade da agricultura

Abstract

Brazilian agribusiness is of great competitivity mostly due to the lack of government subsidies and the historical efforts made in research and development by the public institutes and Universities. Nevertheless the Brazilian agriculture is fundamented in the use of fertilizers and agrochemicals that needs to be imported in huge amounts to supply the Brazilian farmers. In this sense, the safety and sustainability of the Brazilian agribusiness is subjected to the supply of these inputs and to the prices prevailing on the international market. In addition, a new concern is emerging in the global society, which has increased demands for food, feed, and energy that must be provided by the agriculture, although new sustainable farming practices urge to be implemented. Natural relationships between plants and soil microbes are on the heart of the matter, with growing scientific data supporting the use of the former-potential plant-bacteria associations in large scale to increase the crop productivity and hence the production of food and energy. The total substitution of nitrogen fertilizers in soybean crops by the biological nitrogen fixation held by rhizobia corroborates the efficiency of such associations, and point out for the need to expand this and other natural mechanisms directed to provide nutrients to cereals and other nonleguminous crops. To achieve this, much effort is also needed to reach a better understanding of the mechanisms controlling plant-bacteria associations, and to develop biofertilizer formulations presenting a high efficiency under a myriad of field conditions, as those found in Brazil. Biotechnological approaches aimed to reach this goal are reviewed and discussed throughout this manuscript. Keywords:Biofertilizer, plant growth-promoting bacteria, plant nutrition, plant inoculation. __________________________Universidade Estadual de Londrina, Departamento de Bioquímica e Biotecnologia, Rodovia Celso Garcia Cid (PR 445), km 380, Campus Universitário, Cx. Postal 6001, Londrina, Paraná, Brasil. *Autor para correspondência: Telefone: (43) 33715473, Fax: (43) 33714440, email: almoliva@uel.br RESUMO O agronegócio brasileiro possui grande competitividade internacional, principalmente pelos esforços historicamente dispendidos por institutos públicos de pesquisa e Universidades. No entanto, muito dos avanços obtidos pelo agronegócio brasileiro é decorrente do uso em larga escala de fertilizantes e agroquímicos, que devem necessariamente ser importados em grandes quantidades para suprir a demanda dos agricultores brasileiros. Neste sentido, a segurança e a sustentabilidade do agronegócio brasileiro estão ameaçadas pela disponibilidade e susceptibilidade destes insumos aos preços praticados pelo mercado internacional. Além disso, a sociedade global apresenta uma nova apreensão quanto à necessidade de alcançar produtividades mais elevadas e de uma maneira mais sustentável, para prover a população crescente com alimentos e energia. As relações naturais existentes entre as plantas e a microbio...

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