【摘要】 <正> 硅是否作物必需的营养元素,目前尚有争论。国外一些研究工作者指出,在缺硅的土壤上施用硅肥,对甘蔗、水稻等作物都有显著的增产效果。日本、朝鲜、斯里兰卡等国的研究者通过一系列的试验证明,在某些水稻土上施用硅肥也是提高水稻产量的必更多还原

【Abstract】 This article deals with silicon supplying levels and the response of rice plant to Si-fertilizer on the major paddy soils derived from red earth in South China.1. The effect of Si-fertilizer is negatively correlated with the content of available silica in soils. It seems that the critical value of available silica in paddy soils derived from red earth on quaternary red clay in the southern China may be lower than that in Japan and Korea, but higher than that of Taiwan province in China.2. The effect of silicate fertilizer on rice is related to the amount of nitrogen fertilizer applied. For paddy soils containing higher available silica, the application of silicate fertilizer under the condition of an usual amount of nitrogen fertilizer showed no significant effect. But with the increase of nitrogen fertilizer apllied, the silicate fertilizer would often significantly increased the rice yield.3. The content of available silica in paddy soils derived from red earth is varied with their parent materials. The content of available silica in the paddy soil derived from granite and red sandstone is about 5mg/100g soil. In pot cultural experiment, application of amorphous silica to these paddy soils increased the dry weight of rice straw by 11.0 g/pot and 8.6 g/pot respectively.4. Because silicate slags are alkaline materials containing CaO, the application to paddy soils in proportion of 0.5% would increase the pH value of soil 0.4—1.0 unit. Results obtained by plant analysis and labelling P³² have proved that the application of CaCO₃ or silicate slags decreased phosphorus absorbed by rice plant about 17%. Therefore, it must be considered to adopt reasonable method and amount in application of the silicate slags as fertilizer in the soils mentioned above.更多还原