磷、硒配施对冬小麦硒吸收及土壤硒形态转化的影响

为研究磷硒配施对冬小麦根土界面硒有效性及形态分级的影响，并探究磷硒配施提高土壤硒有效性的可能机制，以冬小麦为试验材料进行根箱培养试验，设置0(P0)、80(P80)、160 mg·kg^-1(P160)3个磷水平和0(Se0)、1 mg·kg^-1(Se1)2个硒水平，分析冬小麦植株磷硒含量、累积量、迁移系数及根际和非根际土5种硒形态含量。结果表明，无论施硒与否，随着磷含量的增加，冬小麦生物量、地上部和根系磷含量均增大。施硒1 mg·kg^-1显著降低了P80和P160水平下冬小麦生物量、P160水平下根系磷含量及各部位磷累积量。在Se1条件下，施磷增加了各部位硒累积量，但显著降低了地上部硒含量和硒从根系向地上部的迁移系数。在Se0条件下，P160处理增加了根际土壤和非根际土壤中的可交换态硒含量。在Se1条件下，P160处理根际土壤中可交换态硒含量显著高于非根际土壤，但铁锰氧化物结合态硒和残渣态硒含量低于非根际土壤。综上所述，适宜的磷硒配施可影响土壤中各种硒形态的转化过程，可能是由于磷的施入和根系活动共同作用促进了土壤中铁锰氧...

Effect of Phosphorus Combined Selenium Application on Selenium Absorption of Winter Wheat and Transformation of Selenium Chemical Forms of in Soil

This paper investigated effect of combined application of phosphorus （P） with selenium （Se） on the availability and chemical fractions of Se in root-soil interface of winter wheat， which helped to investigate a possible mechanism for increase of Se uptake by winter wheat through combined application of P with Se， and to provide a theoretical basis through reasonable P and Se application in agricultural production. A rhizobox culture experiment with three P （NaH₂PO₄·2H₂O） application rates 0 （P0）， 80 （P80）， 160 mg·kg^-1 （P160） and two Se （Na₂SeO₃·5H₂O） application rates 0 （Se0）， 1 mg·kg^-1 （Se1） was conducted to analyze the P and Se concentrations， accumulation， transport coefficient and Se chemical fractions in rhizosphere and non-rhizosphere soil of winter wheat. Results showed that， regardless of Se application， biomass and P concentration in shoots and roots of winter wheat were increased with the increasing P application. Se application （Se1） significantly decreased dry matter weight， P concentration in roots and P accumulation in each tissue. At Se1， P application （P80 and P160） significantly increased Se accumulation in each tissue， but significantly reduced Se concentration in shoots and Se migration coefficient form roots to shoots. At Se0， P160 treatment increased the concentration of exchangeable Se in rhizosphere and non-rhizosphere soil. At Se1， the concentration of exchangeable Se in the rhizosphere soil was higher than in non-rhizosphere soil， but the concentration of iron-manganese and residual Se were lower than that in non-rhizosphere soil. Appropriate combined application of P with Se promoted transformation of chemical forms of Se in soil， enhanced Se absorption and accumulation of winter wheat， which may be due to the combined effect of P application and root activity promoting transformation of Se from iron-manganese and organic sulfide bound Se to exchangeable Se to improve the bio-availability of Se in soil.