不同价态硒对小白菜生长及土壤硒形态的影响

Effects of Selenium with Different Valences on Growth of Brassica chinensis and Selenium Species in Soil

采用田间小区试验,研究不同价态硒对小白菜生长、硒吸收和土壤硒形态的影响.结果表明,适当含量(<2.5mg/株)的两种价态硒对小白菜生物量增加有促进效果,而高含量(>5 mg/株)则有明显的抑制作用.两种价态硒处理显著增加了小白菜硒含量,在7.5 mg/株处理达最大值,分别为0.401 mg/kg和2.207 mg/kg,较对照增加了2.0倍和15.5倍.相同浓度条件下,六价态硒处理的小白菜硒积累量和硒的有效利用率均显著大于四价硒处理.两种价态硒处理可有效提高土壤各形态硒含量,且四价态硒效果好于六价态硒.小白菜硒含量受土壤中交换态硒含量的影响最大,其次为水溶态硒含量.

In order to study the effects of Se（IV） and Se（VI） on the growth of plant and the soil selenium forms,we used Brassica chinensis as the experimental object by field plot experiment.The results showed that the biomass of Brassica chinensis increased with appropriate concentration（2.5 mg/strains）of Se（IV） and Se（VI）,while significantly decreased with high concentration（5 mg/strains）.The selenium content in plant enhanced and reached 0.401 mg/kg and 2.207 mg/kg,which was 2.0 times and 15.5 times of the control with the treatments of Se（IV） and Se（VI）,respectively.The selenium accumulation and utilization of Brassica chinensis with the applying Se（VI） were significantly better than those of Se（IV） under the same concentrations.The selenium species with the treatment of Se（IV） increased remarkably more than those of Se（VI）.It was found that the selenium content of Brassica chinensis had the best correlation with exchangeable selenium,and then the water soluble selenium.