Most of agricultural production in Latin America consists of smallholder farmers who need the development of sustainable technologies, with costs according to their economic condition. Biofertilizers composed of free-living bacteria promote plant’s growth, improve productivity through the strengthening of its roots, and reduce the amount of synthetic fertilizer applied to the crops. The aims of this chapter are to highlight the microorganisms commonly used in agriculture as biofertilizers and the main researches carried out in several countries of Latin America, and to describe the development of an experimental biofertilizer for maize, based on strains of Azospirillum spp. and Pseudomonas fluorescens, in the highlands (Sierra Region) of Ecuador. Seven phylum and 95 genera o microorganism used as biofertilizers or Plant Growth-Promoting Rhizobacteria (PGPR) are summarized, along with the benefits, challenges and future prospect of their use. The effectiveness of the experimental biofertilizer developed in Ecuador was demonstrated through several experiments at the green house and field, in which it was evident the increase of root’s size, the amount of crocket, the percentage of dry matter, and the crops´ yield. The evaluations, accomplished on farmers’ fields showed 30% of increase in yield and 21% of decrease in the cost of production per kilogram; as a consequence of the use of biofertilizer plus 50% of the recommended chemical fertilization, in comparison with standard farming techniques. Farmers can reduce the application of synthetic fertilizers and sustainably increase crop yield through the use of this technology.
Part of the book: Technology in Agriculture