水稻对外源硒的吸收利用研究

硒是人体必需的微量营养元素,食物是人体硒的主要来源,外源硒调控是生产富硒农产品的重要手段之一。通过盆栽试验,研究外源硒添加条件下水稻对硒的吸收利用问题。结果表明,土壤添加外源硒为0.2~0.6 mg Se·kg~(-1)土的条件下,对水稻的生长性状没有显著影响,但能显著增加水稻各部位的全硒含量。硒在水稻体内各部位的含量大小关系为:稻根茎叶糙米精米谷壳;但在各主要部位的总累积大小为:茎叶糙米精米稻根谷壳。在自然土壤上硒相对更多地富集于水稻根系,而外源添加四价硒处理,水稻吸收的硒相对更容易转移至地上部位,甚至更容易在糙米和精米中富集。水稻植株对外源硒的吸收利用率为2.87%~3.75%,地上部和籽粒累积外源硒的量占添加外源硒总量分别为2.60%~3.45%和0.94%~1.32%。

Effects of Exogenous Selenium on Paddy Rice Growth,Selenium Uptake and Accumulation

Selenium(Se) is an essential micronutrient for humans which mainly comes from food, Se amendment to soil is one of important ways to produce selenium-enriched foods. In this paper, pot experiment had been taken at four exogenous selenite levels(0, 0.2, 0.4 mg Se· kg-1 soil and 0.6 mg Se·kg-1 soil) to investigate the effects of Se amendment to soil on paddy rice growth, Se uptake and accumulation. With Se adding levels to soil ranged from 0.2 to 0.6 mg Se·kg-1 soil, there were no significant effect on rice growth, but the total Se concentrations in paddy rice fractions increased significantly. The total Se concentrations in paddy rice fractions were in the following order:root>straw>unpolished rice>polished rice>husk, but the total Se accumulations in paddy rice fractions were in the following order:straw>unpolished rice>polished rice>root>husk. When paddy rice grew on the natural soil, Se relatively more enriched in roots, while the treatment amended with selenite, rice absorption of Se transported to the aboveground parts more efficiently, even more easily accumulated in unpolished and polished rice. The utilization of paddy rice, aboveground biomass and grain accumulated added-selenium were 2.87％～3.75％, 2.60％～3.45％ and 0.94％～1.32％ respectively.