高等植物硅素营养研究进展

The Advance in Research of Silicon Nutrition of Higher Plants

硅在地壳中含量为27.6%,大部分以二氧化硅(SiO2)的形态存在,能被植物吸收的有效硅只有50～250mg/kg,植物吸收硅后土壤溶液中硅的浓度仍能保持在一恒定水平.硅在植物内主要以二氧化硅胶(SiO2*nH2O)的形态存在于表皮细胞和细胞壁上,含量随物种不同而差异很大,同时还受植株部位、栽培方式及环境条件等因素影响.植物吸收硅主要以单硅酸形式,不同植物吸收硅的能力不同,水稻具有主动吸收硅的能力,大多数植物被动吸收硅.硅素对植物的形态结构和体内其它元素产生影响,能调节植物的光合作用和蒸腾作用,能增强植物抗倒性和抗旱性,高浓度的硅对真菌孢子的萌发和菌丝的生长有抑制作用,硅素能够提高植物对病虫害的抗性,降低病虫害的发生.

The earth＇s crust contains about 27. 6% of silicon, but main form of silicon is silica dioxide （SiO2）. There are only 50-250 mg/kg of available silicon in soil that can be absorbed by plants. The soil can keep the concentration of silicon in soil solution to a constant level even after plants took it up. Silicon mainly deposits in the cuticular cells and cell wall of plants in the form of SiO2·nH2O. Silicon content in plants varies greatly with plant species and plant parts orgasm of the same plant, cultivation methods and environmental factors affect silicon contents. Plants absorb silicon mainly in the form of mono-silicic acid. The ability of silicon absorption varies obviously with plant species. Rice can uptake silicon actively and most of other plants uptake silicon passively. Silicon can affect plant＇s morphology and uptakes of other elements,and improve photosynthesis and respiration ,which contributes to lodging and draught-resistance. Higher silicon contents in plant can control bourgeoning of epiphyte spore and hyphal growth. The application of silicon fertilizer can improve the plants resistance to disease and pest and thus decrease the occurrence of them.