Distribution characteristics of selenium content in rice and rhizosphere soil in Luzhai,Guangxi

ObjectiveThe present study was conducted to study distribution characteristics of rice and rhizosphere soil in Luzhai,Guangxi,in order to provide a theoretical basis for industrialized,large-scale and scientific production of se-lenium-enriched rice in Guangxi. MethodTwenty-eight sets of representative rice plants and corresponding rhizosphere soil samples were collected from Luzhai,Guangxi,and the selenium content in different parts of rice plants was determined by hydride atomic fluorescence spectrometry,compared with selenium content of corresponding rhizosphere soil,so as to investigate ability of rice to enrich selenium during growth process. ResultResults showed that,enough-selenium rate,se-lenium-enriched rate and selenium poisoning rate of 28 rice rhizosphere soil samples accounted for 3.57%,92.86% and 3.57% of total samples. Twenty-six of twenty-eight seed samples were up to standard of selenium enrichment,selenium-enriched rate was 92.86%,but two of which were lower than standard,accounting for 7.14%. Distributions of selenium con-tents in different parts of rice plant and rhizosphere soil were ranked as follows:rhizosphere soil>root hair>cauline leaf>seed. Selenium content of corresponding rhizosphere soil was extremely significantly positively correlated with selenium content of seeds,cauline leaf and root hair,respectively(P<0.01),however,this correlation was attenuated with the increase of distance between rhizosphere soil and each of root,cauline leaf and seed. ConclusionPaddy soil of Luzhai,Guangxi is rich in selenium,with an average selenium content of 1.002 mg/kg,which is much higher than national average(0.29 mg/kg), 92.9%of total rice reach up to national standard of selenium-enriched rice,therefore,Luzhai of Guangxi has natural condi-tion for production of selenium-enriched rice.