为了揭示硫酸盐处理下小麦对亚硒酸盐和硒酸盐的吸收与转运规律,通过溶液培养,研究了不同浓度硫硒交互下小麦各部位的硒含量变化.结果表明,与无硫处理相比,0.1 mmol· L-1硫使小麦对硒酸盐的吸收潜力(Vmax值)和亲和力(1/Km值)分别降低了25.7%和90.8%,硫酸盐主要是通过降低小麦根系对硒酸盐的亲和力来缩小其与亚硒酸盐的吸收差异.小麦硒转移系数(TF值)随亚硒酸盐浓度的升高显著下降,降幅最高达35.3%,硫酸盐对其无显著影响;TF值随溶液中硒酸盐浓度的升高显著上升,最高增幅达53.8%,硫酸盐对其有显著促进作用.经亚硒酸盐处理后,无论施硫与否,小麦根部累积的硒均会随培养时间的延长显著向地上部运输;而经硒酸盐处理后,小麦根部累积的硒只在硫酸盐存在下才会随培养时间的延长显著运往地上部.富硒地区施用硫肥既可防止土壤硒的过度消耗,又可促进硒向可食部位的转移.
In order to explore how wheat uptake and translocate selenite and selenate when treated by sulfate (S), we studied selenium (Se) concentration changes at different parts of wheat under the interaction between different concentrations of Se and S based on hydroponic experiment. Results showed that the addition of 0.1 mmol· L-1 S reduced the uptake potential ( Vmax) and the affinity ( 1/Km) of wheat on selenate by 25.7% and 90. 8%, respectively, compared to the zero S treatment. S reduced the uptake difference of Se treated with selenite and selenate mainly by reducing the affinity of seleuate on wheat root. Translocation factor (TF) of Se significantly reduced as the concentration of selenite increased, with maximum decreasing amplitude of 35.3%, while S showed no significant impact. TF of Se significantly increased as the concentration of selenate increased, with the maximum increasing amplitude of 53.8%, and S significantly promoted such increase. After selenite treatment, Se accumulated in wheat root was continuously transported towards shoot regardless of whether treated by S or not. After selenate treatment, Se accumulated in wheat root was continuously transported towards shoot only under S treatment conditions. The application of S fertilizer could prevent excessive consumption of Se in soil, promoting Se translocation towards edible parts.