Abstract:
Objective Effects of rice variety and applied foliar fertilizers on the accumulation of heavy metals in the husk-removed grains were studied.
Method In a field experimentation, 10 major local late-season rice cultivars in Guangxi Province were sprayed with selenium (Se), silicon (Si), or water as CK. Contents of As, Cd, Pb, and Cr in the husk-removed grains were determined to identify the rice varieties with lower potential to retain heavy metals.
Result Significant differences were found in the pollutants accumulation of rice grains. Among the 10 cultivars, Guiyu 12 was the lowest on Cd, Yufengyou 158 the lowest on As, Quanxiangyou 822 the lowest on Cr, and only Huazheyou No.1 detected with Pb. The greatest to the least heavy metal accumulated was in the order of Cd>As>Cr>Pb. On average, the application of Se foliar fertilizer reduced the Cd accumulation in grains by 44.8%, and that of Si by 44.2% with the enrichment coefficients decreased by 47.2% and 47.4%, respectively. Si application lowered the As content by 30.0% with an enrichment coefficient by 19.0% over CK, but less effective on Pb reduction.
Conclusion The accumulation of Cd in the grains of Guiyu 12 could be significantly minimized, and also that of As in Yufengyou 158 rice, for the cultivation in Guangxi. Application of Si fertilizer on the leaves of a rice plant could decrease As accumulation and that of either Se or Si reduce Cd in the grains.