Characteristics of Selenium Content in Different Soil Types in Guanzhong and Its Influence on Selenium Content of Corn Grain

This paper selects fluvo-aquic soil, aeolian sandy soil, cinnamon soil, black loessial soil, red soil, alluvial soil in Guanzhong of Shaanxi Province and corn growing on them as the research objects. 74 corn samples and 74 root soil samples were collected, and soil Se content, Se speciation and its influencing factors, the effect of soil Se content variation on corn grain Se content were analyzed. The results showed that contents of total Se and various Se fractions of both cinnamon soil and alluvial soil were significantly higher than those of other four soil types, and cinnamon soil and alluvial soil were Se rich soils. The bio-available Se content of cinnamon soil and alluvial soil was significantly higher than that of other four soil types. The Se content of corn grain in cinnamon soil and alluvial soil met the standard of selenium enrichment, and was significantly higher than that of corn grain in the other four soil types. Furthermore, the Se content in corn grains increased when soil Se content increased to a certain level. These results suggested that cinnamon soil and alluvial soil with higher selenium content were suitable for selenium-rich corn. This study is of help to understand the physical and chemical properties of soil in Guanzhong area and the relationship with Se availability. It provides theoretical basis for the adjustment of soil selenium level, the improvement in plant selenium nutrition status, the development and utilization of selenium-rich resources and the adjustment of planting structure.