CHARACTERIZATION AND IDENTIFICATION OF ARBUSCULAR MYCORRHIZAL FUNGAL SPORES IN SIX CROPS FROM THREE LOCALITIES IN THE TEPEACA VALLEY, MEXICO

Abstract

The objective of this study was to characterize and identify arbuscular mycorrhizal fungal (AMF) spores associated with economically important vegetable crops in the Acatzingo, El Cristo, and Santa María Actipan localities within the horticultural zone of the Tepeaca Valley, Puebla, Mexico. Arbuscular mycorrhizae are mutualistic symbioses established between fungi of the phylum Glomeromycota and the cortical cells of plant roots. This association contributes to plant adaptation to terrestrial environments by providing the fungus with carbohydrates, while the fungus facilitates the uptake and transport of phosphorus, nitrogen, and water from the soil. Two sampling events were conducted in April and August 2023, during which a total of 90 soil samples and 54 plant samples were collected from six vegetable crops. Spores were extracted from soil, and roots were stained using the Phillips-Hayman technique to detect mycorrhizal structures. Nine AMF genera and 14 morphotypes were identified, with Funneliformis mosseae, Claroideoglomus claroideum, and Glomus sp. being the most frequently observed taxa. Mycorrhizal structures, particularly vesicles and spores, were detected in four of the six crops, whereas no AMF structures were observed in pumpkin roots. Soil physicochemical characterization showed soil moisture contents of 9.4–13 %, water retention capacity of 41.3–50.9 %, pH values of 5.87–6.87, and electrical conductivity of 0.1–0.93 mS cm-1. Soil texture ranged from sand to sandy loam, with sandy particles predominating. These results provide a baseline for the diversity of AMF associated with vegetable crops in the Tepeaca Valley and show the potential influence of soil physicochemical properties on AMF occurrence and diversity.