外源硒对大豆产量、植株氮磷含量及土壤酶活性的影响

利用盆栽试验，研究了不同浓度、不同价态外源se对大豆产量、N、P含量及与N、P代谢密切联系的土壤脲酶和磷酸酶活性的影响．结果表明，施用浓度为0．25和0．5μg·g^-1土的Se^4+和Se^6+后，大豆产量、含N量及土壤脲酶活性增加，大豆含P量和土壤磷酸酶活性降低．当Se^6+浓度为0．5μg·g^-1土时，大豆植株含N量与土壤脲酶活性呈极显著的抛物线相关关系；Se^6+浓度为0．25μg·g^-1土时，大豆植株含P量与土壤磷酸酶活性呈极显著的抛物线相关关系。Se^4+处理的大豆N、P含量和土壤脲酶和磷酸酶活性均无显著相关关系。

Effect of exogenous selenium on soybean yield and its total N and P contents and on soil enzyme activities

Based on pot experiment with black soil, the effects of various concentrations and various valence of exogenous selenium on soybean yield and its N and P contents and on soil enzyme activities were studied. The results showed that applying 0.25 microgram.g-1 soil and 0.5 microgram.g-1 soil of both Se4+ and Se6+ could increase soybean yield and its N content and promote soil urease activity, but decrease the P content of soybean and soil phosphatase activity. When the concentration of Se6+ was 0.5 microgram.g-1 soil, there was a significantly parabola relationship between the N content of soybean and soil urease activity; and when the concentration of Se6+ was 0.25 microgram.g-1 soil, there was a significantly parabola relationship between the P content of soybean and soil phosphatase activity. There were no significant relationships between the N and P contents of soybean and the activities of test soil enzymes when Se4+ was applied.