The tendency of conventional agriculture to achieve high yields has imposed a need for specialization of production and intensive application of mechanization, irrigation, pesticides, mineral fertilizers and new plant varieties. In this way, on the one hand, the profit of farmers is...

This paper approaches an extremely current topic, namely the substitution of synthetic nitrogen, very expensive and polluting, with nitrogen of biological synthesis, through the peas and Rhizobium system, cheap and nonpolluting. The entire economy is going through a period of crises, generated...