MICROBIAL COMMUNITY PROFILES IN RESPONSE TO DIFFERENT SOIL MANAGEMENTS IN SANDY SOIL

The growing human population has higher and higher food demand, which requires an increase in efficiency of agricultural production. Healthy and fertile soils are essential to satisfy this demand. The microbial community structure is an excellent indicator of the soil fertility and the diversity of bacteria and fungi. In our work we compared the effect of organic and conventional cultivation methods on the microbial community profiles of sandy soils in the Nyírség region, Hungary. These fields have topographical heterogeneity therefore the sampling sites were divided into top of hill and bottom of hill. Sampling was done in autumn 2013, from the 0-30 cm and the 30-60 cm soil depths. The phospholipid fatty acids (PLFA) were used for the monitoring of microbial community. PLFAs break down when the cell dies therefore these molecules show the community structure in a real time. In the 0-30 cm soil layer of organically managed field the PLFA structure was significantly different between top and bottom of hill, but the difference were low. In conventionally managed field, high differences were found between the PLFA groups measured in the top and bottom of hill. The PLFA values were higher in the top of hill in organic field, while in case of bottom of hills sites higher PLFA values were measured in conventional farming system. In the deeper soil layers the tendencies were found similar to the upper soil layer, but the measured values were lower.