不同形态叶面硒肥对水稻吸收和转运硒的影响

通过田间试验，研究了不同形态叶面硒肥对水稻吸收和转运硒的影响。与空白对照相比，亚硒酸钠、硒酸钠、硒代蛋氨酸和化学纳米硒在水稻扬花期一次施用（15 g/hm2）可使水稻籽粒、颍壳和秸秆的硒含量分别提高0.06～0.64 mg/kg、0.36～0.83 mg/kg和0.32～0.75 mg/kg。籽粒硒的回收率先后顺序为：硒代蛋氨酸（34.6%）>亚硒酸钠（15.7%）>硒酸钠（15.0%）>化学纳米硒（6.6%）；硒在水稻各部位中的分配比例的先后顺序为：秸秆＞籽粒＞颍壳。此外，硒用量与水稻籽粒的硒含量呈现极显著线性相关关系。按照黑龙江省富硒大米的地方标准（DB23T 790-2004）一等大米的硒含量指标（0.20～0.30 mg/kg），亚硒酸钠单施的施用量为6.01～10.62 g/hm2，腐植酸+亚硒酸钠复合肥的施用量为4.26～8.63 g/hm2。硒代蛋氨酸的富硒效率高于其他三种硒形态，腐植酸+亚硒酸钠复合肥的富硒效率高于亚硒酸钠单施。

Effects of Different Forms of Foliar Selenium Fertilizers on Se Accumulation and Distribution in Rice (Oryza sativa L.)

Field experiments were carried out to study the effects of different forms of selenium foliar fertilizers on the absorption and transportation of Se by rice. Compared with the control treatment, sodium selenite, sodium selenate, selenomethionine, chemical nano-Se foliar applied once (15 g/hm2) at the flowering stage of rice could increase Se contents of grain, husk and straw by 0.06~0.64 mg/kg, 0.36~0.83 mg/kg and 0.32~0.75 mg/kg respectively. Grain Se recoveries showed the following ranks: SeMet (34.6%)>sodium selenite (15.7%)>sodium selenate (15.0%)>chemical nano-Se (6.6%); while the ranking of Se distribution in the different parts of rice was: straw>grain>husk. Furthermore, grain Se contents increased significantly with the increase of Se application dosages. When applied selenite of 6.01~10.62 g/hm2 or humic acid+selenite of 4.26~8.63 g/hm2, Se contents in rice grains could meet the standard first grade for Se-enriched rice proposed by Heilongjiang Province (0.20~0.30 mg/kg). Biofortification efficiencies of Se applied as SeMet and HA+Se were greater than other three Se forms and selenite respectively.