外源草酸影响下植酸酶对土壤磷素的活化效果

Effects of phytase on phosphorus release under the influence of exogenous oxalic acid

通过室内培养,采用Hedley修正体系磷素分级的方法,阐述了外源草酸影响下,植酸酶对土壤中磷素的活化效果。结果表明:同时施入草酸与植酸酶处理可提高土壤有效磷含量,显著高于空白、单施草酸或植酸酶的处理。从磷素各组分看,同时施入草酸与植酸酶处理能够显著提高土壤中水溶态磷(H2O-P)、活性无机磷(NaHCO3-Pi)、中等活性无机磷(NaOH-Pi)和中等活性有机磷(NaOH-Po)含量,均随着培养时间的延长而不断上升,在第40 d上升至最大值,与空白对照比较,分别高37.76%,21.14%,15.52%,24.44%;草酸+植酸酶处理的土壤,除NaHCO3-Pi外,其他活性高的磷含量均高于植酸酶处理;施入植酸酶各处理的土壤磷石灰型磷以及残留态磷含量均低于空白对照及草酸处理,且随着培养时间的延长其含量下降,到第40 d开始逐渐趋于平稳,此时,草酸+植酸酶处理磷石灰型磷以及残留态磷含量分别比培养前降低了28.71%与32.56%。得出结论,在外源草酸影响下,植酸酶可使土壤磷由活性低的组分转化为活性较高的组分,从而提高磷素的利用率。

Effects of phytase on phosphorus release under the influence of exogenous oxalic acid were studied using lab-syn- thesis method and the Hedley sequential phosphorus fractionation scheme. The results showed that the treatment of applied in oxalic acid and phytase together could improve the soil effective phosphorus content, significantly higher than the contrast processing treatment of blank, oxalic acid and phytase. From the various components of phosphorus, the treatment of ap- plied in oxalic acid and phytase together could increase the amounts of H2 O-P, NaHCO3-Pi, NaOH-Pi and NaOH-Po and they reached the highest in the 40th day, with the extension of incubation time rising, which higher than blank control 37.76%, 21.14%, 15.52%, 24. 44% ; Labile phosphorus amounts except NaHCO3-Pi of the treatment of applied in ox- alic acid and phytase together were higher than the treatment of phytase ; The amounts of HCI-P and Residual-P of the treat- ment contain phytase were lower than those of blank and oxalic acid treatment, and with the extension of incubation time its amount decline, which stabilized in the 40th day. At this time, the amounts of the treatment of applied in oxalic acid and phytase together was lower 28. 71% and 32. 56% than before. Conclusion, under the influence of exogenous oxalic acid, phytase could make the labile phosphorus component into stable components, so as to improve the utilization ratio of phos- phorus.