BENEFITS OF JOINT MANAGEMENT OF GREEN MANURE AND MYCORRHIZAL INOCULANTS IN CROP PRODUCTION

Abstract

Background. Nutrient supply is a decisive component of agricultural systems, but in Cuba only 25 % of cultivated areas can be fertilized, influencing their productivity negatively. From the benefits of the use of mycorrhizal inoculants and green manures and the mycorrhizal dependence of Canavalia ensiformis, the hypothesis of integrating both was evaluated. Objective. To establish nutrient supply schemes that guarantee high yields with lower amounts of fertilizers, as well as new routes for mycorrhizal inoculation of crops. Methodology. The canavalia response to the inoculation of three generalist AMF strains was evaluated in eight edaphic conditions, as well as eight integration experiments of the green fertilizers inoculated with the efficient strain in the nutrient supply schemes of cassava, banana, corn, tobacco, mulberry and king-grass. Results. Canavalia responded positively to inoculation, with average increases in biomass and NPK contents of 50 and 70 % respectively, as well as mycorrhizal propagules. The effectiveness of the applied strains depended on the edaphic conditions and presumably the soil pH. The canavalia inoculated with the efficient AMF strain and used as the preceding and/or intercropped green manure was successfully integrated into the nutrient supply systems of the different crops, guaranteeing high yields, effective mycorrhizal function and decreasing between 25 and 75 % the amounts of fertilizers applied to them. Implications. The benefits and feasibility of the joint management of green manures and mycorrhizal inoculants in agricultural production are demonstrated, as well as being a successful way to achieve effective mycorrhization in crops whose direct inoculation is prohibitive due to the high amounts of biofertilizer or laboriousness. Conclusion. The integration of AMF inoculants and green manure increased the benefits of both practices and it is a promising way of managing the arbuscular mycorrhizal symbiosis in sustainable crop production.