Soil microorganisms as indicators of agricultural correction efficiency

Abstract

The liming technique is used to modify and balance the hydrogenic potential (pH) of soils, which can influence their microbiota. Microorganisms act as a biological indicator, important for their ability to respond quickly to changes in the soil and for their participation in several processes necessary for the good development of crops. Thus, the objective was to evaluate soil microorganisms as indicators of the efficiency of agricultural correctives over time. For this, the superficial layer of a sandy soil was collected, and through chemical analysis obtained the need for liming, being established the following treatments: T1 – Control (soil without correction); T2 - Conventional Calcitic Limestone (42% CaO and 2% MgO); T3 - Product A - 48% calcium oxide + 34.3% calcium + 1% magnesium oxide + 0.6% magnesium; T4 - Product B - 48% calcium oxide + 34.3% calcium + 1% magnesium oxide + 0.6% magnesium + Lactobacillus bacteria + Saccharomyces yeasts. Samples for microbiological analysis were collected before the application of treatments and at 30, 60 and 90 days after application. 10 g of soil were weighed every 5 cm of depth and these were serially diluted to 10-4, from which an aliquot of 0.1 mL was taken and placed on potato dextrose agar medium. The application of soil amendments did not provide significant variation in pH values ​​during the evaluated period. And there were changes in the population of bacteria and fungi present in soil samples at all depths and treatments evaluated, but not significantly. Thus, it is suggested the development of future researches that evaluate the microbial groups affected by the correctives, because quantitatively significant differences were not observed.