Arbuscular mycorrhizal fungi activity in Haplic Luvisol on the semi-arid region of Pernambuco – Brazil

The use of microorganisms aiming to improve the availability of nutrients for plants is an important and necessary practice for agriculture. Thus, studies on the AMF occurrence in the brazilian northeastern and efficiency tests using native plants in the region have been intensified on recent decades. Aiming to determine the most probable number (MPN) of infective propagules in the area with native vegetation on the semi-arid region of Pernambuco, municipality of Sertânia, quantify the soil protein related to easily extractable glomalin (SPREEG) and to total glomalin (SPRTG), experiments were conducted in a greenhouse. For this study 10 composite soil samples were collected, with points randomly defined. Samples were homogenized and analyzed for physical and chemical characteristics. Being used for immediate examination and preparation trap cultures (one three-month cycle of propagation) to AMF, using as host plants sorghum (Sorghum bicolor L. Moench), and peanut (Arachis hypogaea L.). To determine the MPN of infective propagules of AMF in Haplic Luvisols, soil inoculum samples were diluted in the proportions of 0, 1:10, 1:100 and 1:1000 (soil inoculum: diluent soil, v:v) with 5 repetitions each, using maize (Zea mays L.) as host plant. The direct count (DC) differed significantly from the indirect (IC) of AMF with averages of 961.3 and 517.4 glomerospores per 100g soil, respectively. The NMP of infective propagules of AMF propagules found was 23 cm-3 and SPREEG and SPRTG were approximately 0.46 and 0.26 mg glomalin g-1 aggregate, respectively.