ARBUSCULAR MYCORRHIZAL FUNGI FROM SAVANNAH SOILS IN TABASCO, MÉXICO

Abstract

Savannah soils are well represented at the state of Tabasco, Mexico. On them the maize is extensively grown and its association with arbuscular mycorrhizal fungi (AMF) could play a significant role on nutrients inflow. Until now in spite de relevance of these micoorganisms for maize nutrition only one arbuscular mycorrhizal species has been recorded from Tabasco maize fields. Under this consideration, the objectives of the study were to quantify the spores of AMF and to identify the species, to estimate the colonization percentage in maize roots, as well as the fertility from five savannah soils; Emiliano Zapata and Humanguillo savannahs are acidic, while Balancán, Tenosique and Tacotalpa are neutral. Low to high fertility was found in all cases. Spore number 100 g-1 dry soil was low (150) to high (750). Mycorrhizal colonization was very high (96-100%). Fifteen AMF species from eight genera were found, so the species for Tabasco reach 20. Glomus ambisporum and Sclerocystis sinuosa were found in all five savannahs, while Funneliformis constrictus the only one AMF species previously reported from maize in Tabasco was not recovered. Savannah similarity was very low, which indicates a peculiar species composition for each.