Diversidade e caracterização morfológica de bactérias em sistemas de produção integrados e exclusivos no norte do estado de Mato Grosso

Abstract

The implementation of integrated production systems has long been considered an alternative to intensify land use in a sustainable manner, however, the different arrangements between agricultural components as well as changes in the climatic conditions can affect the bacterial community present in these environments. In view of this the objective of this study was to verify the diversity of bacterial colonies, seasonal effects of land use and the presence of isolates capable of solubilizing phosphate in vitro. The experiment was composed by 5 treatments with different arrangements (1- Eucalyptus, 2- tillage soya in the summer and corn in 2o season, 3- pasture, 4- integrating agriculture florest, 5- integration pasture florest). Randomized block design with four replications, were also analyzed an area of native forest and fallow. The samplings were conducted in March and September, respectively rainy and dry period. From each sample dilutions, followed by inoculation were performed in Petri dishes containing the culture medium DYG'S, these plates were maintained at 28 °C and after 48 hours the count of colonies forming units was performed subsequently isolates purified were characterized according to their characteristics morphological and tested for ability to solubilize phosphate. The number of colonies forming units ranged between 106 and 107of CFU.g-1, and the larger amount was found the rainy season in all treatments. The difference in the morphological characteristics of the isolates allowed to find 77 different phenotypic groups. Isolates at 80% similarity, during the rainy season were grouped into 13 groups whereas during the dry period formed 14 groups. Isolates were found capable of solubilizing phosphate in vitro in all areas, and during the rainy season the greatest quantity was found.