外源硒对茎瘤芥硒形态及硒吸收的影响

Effect of Exogenous Selenium on Selenium Speciation and Uptake in Brassicajuncea var. tumida Tsen et Lee

采用大田实验研究叶面喷施硒(0.0、1.0、2.5 mg/L)对茎瘤芥生长、硒形态、硒吸收和转化的影响。结果表明,叶面喷施1.0 mg/L的硒提高了茎瘤芥的产量,但未达到显著水平(P>0.05)。叶面喷硒降低了茎瘤芥硝酸盐含量,在一定程度上增加了茎瘤芥游离氨基酸、VC、还原糖的含量,分别较对照增加了40.41%、13.36%和46.73%。叶面喷施硒后茎瘤芥中全硒和有机硒含量分别较对照增加了46.1%~193.9%和74.0%~271.5%,并且随外源硒质量浓度的升高而显著增加。随硒质量浓度的增加,茎瘤芥有机硒转化率显著提高,1.0、2.5 mg/L硒处理分别较对照增加了19.33%和23.57%。茎瘤芥吸收的硒主要以有机硒的形式存在,茎瘤芥全硒和有机硒含量与外源硒质量浓度呈极显著正相关(P<0.01)。

Field experiments were carried out to investigate the effects of exogenous selenium (0.0, 1.0 and 2.5 mg/L) on the growth, selenium speciation and selenium uptake of Brassica juncea var. tumida Tsen et Lee. The results showed that foliar spraying of selenium (1.0 mg/L) increased the growth of Brassica tumida Tsen et Lee but its effect was not significant (P > 0.05). Foliar spraying of selenium (Se) reduced the nitrate content of Brassica juncea var. tumida Tsen et Lee, while itincreased free amino acids, VC and reducing sugar by 40.41%, 13.36% and 46.73% compared with the control, respectively.Foliar selenium application increased the concentrations of total and organic Se by 46.1%–193.9% and 74.0%–271.5%compared with the control, respectively, and this effect was concentration dependent. The transformation rate of organicselenium in Brassica juncea var. tumida Tsen et Lee applied with 1.0 and 2.5 mg/L Se significantly increased by 19.33% and23.57% compared with the control, respectively. Organic selenium was the dominant selenium species in Brassica juncea var. tumida Tsen et Lee. The contents of total and organic selenium in Brassica juncea var. tumida Tsen et Lee revealed a positive correlation with the exogenous selenium concentration (P < 0.01).