REDUCCIÓN DE LA FERTILIZACIÓN INORGÁNICA MEDIANTE MICORRIZA ARBUSCULAR EN SORGO

Abstract

The role of arbuscular mycorrhizal fungi (AMF) has been emphasized in the fields of conservation and soil fertility. The objective of this study was to explore the response of sorghum DKS60 in 2011 and 83G19 in 2016—with respect to plant physiology and productivity—to AMF (Rhizophagus intraradices) alone or combined with half of inorganic fertilizer (IF50 %), compared with conventional fertilization (120N-40P-00K; IF100 %). Profitability was estimated through grain yield with a benefit-cost (b/c) indicator. All treatments exceeded significantly the control with respect to chlorophyll index (SPAD), plant height, stem diameter, panicle length and grain yield, although overall the highest values were recorded with IF100 % and IF50 % + AMF. However, the benefit-cost relationship demonstrated that IF50 % + HMA and AMF alone obtained 1.45 and 1.5 b/c, respectively, higher than the profitability obtained with IF-100 % (1.3). This, although AMF alone recorded 852 kg/ha less than the average of IF100 % and IF50 % + AMF. Reduction or replacement of inorganic fertilization through AMF may represent a viable practice promoting greater profitability, as well as the conservation of agro-ecological production systems.