Diversidad de hongos micorrícicos arbusculares en maíz con cultivo de cobertura y biofertilizantes en Chiapas, México/Diversity of arbuscular mycorrhizal fungi in maize with cover crops and biofertilizers in Chiapas, Mexico

The present work was conducted with the objective of know the density, abundance and diversity of arbuscular mycorrhizal fungi (AMF) associated with maize (Zea mays L.) in plots that have been managed with low incomes of external inputs green manure/cover crop (AVCC) and biofertilizers. The work was conducted in seven farmer plots with maize crop, of which three have been managed with nescafe bean (Mucuna deeringiana Merr.) as AVCC and four without such antecedent of managing. In each plot were established four treatments of biofertilization: 1) inoculation with AMF, 2) foliar application of organic fertilizer, 3) mycorrhizal inoculation with foliar organic fertilizer, and 4) control, which were ordered under a randomized complete block design with seven replications. In total we identified 23 morphospecies, 14 of which were carried at level of species, being Glomus and Acaulospora the dominant genera. The number of species in plots with AVCC was 50% higher than without AVCC. In the plots with AVCC was found 91.3% of morphospecies of AMF, while in plots without AVCC the 60.9%. The percentage of mycorrhizal colonization was not significantly different (p=0.7630) between plots with and without AVCC, but the colonization level was higher with mycorrhizal inoculation (86.6%) that in the control (71%). We conclude that AVCC and inoculation with mycorrhizae had a positive effect on species diversity of AMF and root colonization, respectively. [PUBLICATION ABSTRACT]