Our research work aimed to evaluate cover crop effects of winter rye on soil characteristics, soil conservation, and yield productivities on potato fields with 15% slope during a fallowed period. There were two controls of bared field without any cultivation and conventional potato cultivation without winter rye. Potato cultivation increased soil pH, organic matter, available phosphate, and exchangeable cation regardless of cover crop cultivation. Sub-soil, particularly, all components of soil chemical properties showed higher value in winter rye cultivation than conventional cultivation. Higher soil density was observed on cover crop cultivation than conventional cultivation resulting from root residues of the cover crop both topsoil and subsoil. Cover crop residues positively affected plant growth and reduced the amount of soil erosion by holding the soil. Although severe soil erosion was seen in conventional cultivation, winter rye cultivation declined soil erosion by 47% during the fallow period on potato slope fields. Distinct soil bacterial communities were detected among treatments and some OTU(Operational Taxonomic Unit)s showed significantly higher abundance in winter rye treatment. Total yield and commercial rate demonstrated no significant differences while higher tuber phosphate, K+, and Mg2+ contents were observed in winter rye cultivation.

In this study, microorganism community characteristics of organic managed soil which applied rye (Secale cereal L.) as green manure for 25 years, were determined. The chemical properties of organic soil showed high level of organic matter and available P2O5, while the level of exchangeable cation was low. The analysis of dehydrogenase activity and carbon source utilization indicated that the values in on organic soil were significantly higher than those of the control. It suggested that the microorganism community of organic soil had high microorganism activity, compared to the control. In addition, when the 16S rRNA genetargeted NGS (Next generation sequencing) analysis was conducted to estimate the class of bacterial community, the class level of bacterial taxon composition on organic soil showed higher portion of Sphingobacteriia, Acidobacteriia, Gammaproteobacteria, Solibacteres and Planctomycetia. By base on the results of various reports in which organic managed soil had high portion of Acidobacteriia and Planctomycetia, the characteristic of taxon composition in organic soil, which showed the high percentages of Ktedonobacteria, Sphingobacteriia, Acidobacteriia and Gammaproteobacteria, was resulted from the application of rye as a green manure for the long term. However, further researches were needed because the crop effect was not considered in this study.