Arbuscular mycorrhiza spore abundance and species richness in main agroecosystems in five regions in southeast Mexico

Abstract

Abstract Geographical setting and agroecosystem management have been found to influence spore abundance and species composition of Arbuscular Mycorrhizal Fungi (AMF) communities. In this study we determine how abundance and composition vary between five regions in Southeast México and between the main agroecosystems within them. Two-way analysis of variance and post-hoc Tukey-tests of spore abundance data of home gardens, mixed maize crops and pasturelands showed higher abundances in Los Altos and Canón Usumacinta than in Los Ríos, a significant region–agroecosystem interaction and no effect of agroecosystem. Analysis by region showed significant differences between agroecosystems in the Chontalpa and the Cañón Usumacinta (Kruskal-Wallis and Mann-Whitney tests), but not in Los Altos, Los Ríos and Southern Quintana Roo. We observed a total of 34 morphospecies from a total of 90 sampling sites and calculated an estimated total richness of 42.7 morphospecies. Estimated richness was higher in Los Rios (31.2.) and Chontalpa (19.1) than in southern Quintana Roo (9.6) and was intermediate in Los Altos (10.4) and Cañón Usumacinta (13.5). Species composition did not vary strongly between regions, as most species occurred in several regions. High spore abundance was associated with the moderate use of agrochemicals and of mechanized cropping practices.