Abstract:
Objective This paper was to clarify the current situation of zinc (Zn) and selenium (Se) contents in Highland barley grain and its cultivated soil in Shigatse, Tibet of China, and to investigate the correlation of Zn and Se contents between grain and soil.
Method A total of 86 samples of highland barley (seven varieties) and 86 of corresponding cultivated soil samples (corresponding to highland barley grain collection place) were collected from 12 counties of the district of Shigatse city. Then, the total element contents in grain and soil and the soil available element contents were determined.
Result The Zn contents in grain of Highland barley ranged from 15.61 mg kg−1 to 19.96 mg kg−1, and the Se contents in grain ranged from 60.88 μg kg−1 to 186.19 μg kg−1. Among them, the variety “Ximala 19” showed strong Se enrichment ability, with 186.19 μg kg−1in grain, which is significantly higher than other varieties. The Zn contents in grain showed no significant difference among different varieties. The contents of soil total Zn and Se were 55.77-82.21 mg kg−1 and 113.43-354.29 μg kg−1, respectively. The soil available Zn and Se contents in soil were 0.50-1.02 mg kg−1 and 14.66-32.25 μg kg−1, respectively. The contents of Zn and Se in most of the tested soils were at a low level, which 40.70% of soil Zn was at a low level, 59.80% of soil Se was lower than the local average level. There was a significant positive correlation among Se content of Highland barley grain with soil total Se and available Se contents. There was a significant positive correlation between the Zn content of Highland barley grain with soil available Zn content.
Conclusion The Zn contents in grain of highland barley samples and the Se contents of more than 80% did not meet the standard of zinc-rich and selenium-rich grains, which needs to be further strengthened. The overall contents of Zn and Se in highland barley cultivation soil are at a medium and low level, so additional Zn and Se fertilizer need to be applied.