Development of release-controlled phosphate containing seedbed by use of biomaterial and visible light-responsive titanium oxide photocatalyst

采用两种生物聚合物(凝胶材料)，即卡拉胶和海藻酸铵，制成了一种含有磷酸盐释放控制的苗床。在苗床中加入作为控释磷酸盐的磷酸氢钙和作为生长因子的海藻糖。以芥菜为试材，在培养箱中培养40d，通过生物聚合物凝胶材料的良好配比来提高生长速度，用可见光响应型二氧化钛光催化剂涂层来减少真菌数量，并通过种子埋藏位置的不同来检验生长速度的差异。通过产量和磷利用率来衡量植株的生长速率。试验结果表明，该育苗床比商品销售的磷肥产量高。这些磷的利用率在20%左右。在全球磷供应紧张的情况下，这些检查是非常重要的，因为使用生物聚合物的苗床能够节省磷，从而减少环境负荷。

A seedbeds containing release-controlled phosphate was made by using two kinds of biopolymer(gel materials), namely, karageenan or alginic acid ammonium. Into the seedbeds, calcium hydrogen phosphate as release-controlled phosphate was added with trehalose as a growth factor. Japanese mustard spinach had been grown up as an examination plant for 40 days in an incubator to the following examinations : to increase the growth rate by good mixed ratios of biopolymer gel materials, to decrease the number of fungi by the coating of visible light-responsive titanium oxide photocatalyst, and to examine the difference of growth rate by the difference of position where seed was buried. The plant growth rates were measured by the yields and phosphorus utilization rates. As the result in the examination, the higher yield was obtained by this seedbed than fused phosphate fertilizer commercially selling. These phosphorus utilization rates were around 20%. When the supply of phosphorus is tight worldwide, these examinations were very significant, because the seedbeds by use of biopolymers have enabled to save phosphorus and therefore to reduce the environmental load.