Effects of lime,phosphate and silicate on selenium availability in soil and selenium accumulation in rice
The availability of selenium in acidic soils in South China is low.The purpose of this study was to investi-gate the effects of lime,phosphate and silicate on selenium availability in acid paddy soil and selenium uptake by rice.The results showed that on the basis of 0.25 mg/kg selenium application,lime,sodium silicate,disodium hydrogen phosphate and their combined application had little effect on rice yield per plant.The effect of improving the selenium content of rice was better under the combined application of lime and sodium silicate and the combined application of lime,sodium silicate and disodium hydrogen phosphate.The content of various forms of selenium in acidic soil was in the order of organic/sulfide bound selenium,residual selenium,iron-manganese oxide bound selenium,exchangeable selenium and water-soluble selenium.Lime and disodium hydrogen phosphate treatment significantly increased the contents of water-soluble selenium and exchangeable selenium that were easily absorbed by plants,and significantly reduced the content of residual selenium that was difficult to use.The combined application of lime,sodium silicate and disodium hydrogen phosphate significantly reduced the content of organic/sulfide-bound selenium.The application of lime and disodi-um hydrogen phosphate could effectively improve the availability of selenium in soil and promote the absorption of selenium by rice.The application of silicate had little effect on the availability of selenium in soil,but it could promote the accumula-tion of selenium by rice.
NETL
NSTL
万方数据
维普
