外源氨基酸硒肥对黄瓜幼苗生长及抗氧化物指标的影响.

[Objective] The present paper aimed to explore the effects of exogenous amino acid selenium fertilizer on the growth and antioxidant indexes of cucumber seedlings, so as to provide reference for efficient raising and cultivation of high-quality cucumber seedlings.[Method] Using amino acid selenium leaf fertilizer as selenium source and cucumber Guiqing No. 1 as material, different concentrations of amino acid selenium(selenium concentrations were 0,2,4,6,8,10,12 and 14 mg/L respectively)were sprayed on the leaf surface of cucumber seedlings at the stage of one leaf and one heart. To study effects of different concentrations of amino acid selenium on agronomic properties, contents of osmotic regulators and antioxidants, antioxidant enzyme activities and selenium enrichment of cucumber seedlings.[Result] The application of different concentrations of amino acid selenium leaf fertilizer significantly influenced the agronomic properties, contents of osmotic regulators and antioxidants, antioxidant enzyme activity and selenium enrichment of cucumber seedlings(P<0.05, the same as below).With the increase of selenium concentration, the growth indexes of cucumber seedlings increased at that start and then decreased. The plant height, plant width, leaf length, leaf width and root length of cucumber seedlings reached the highest value at selenium concentration of 2 mg/L, and the lower stem length and total chlorophyll content reached the highest value at selenium concentration of 10 and 6 mg/L respectively; The contents of soluble protein, ascorbic acid(AsA)and proline(Pro)in roots, stems and leaves of cucumber seedlings increased at that start and then decreased; The content of malondialdehyde(MDA)in roots, stems and leaves of cucumber seedlings decreased at the start and then increased; When the concentration of selenium was 4 mg/L, the activity of superoxide dismutase(SOD)was significantly increased, while the activities of peroxidase(POD)and catalase(CAT)were the highest at 10-14 mg/L; The total selenium content in roots, stems and leaves of cucumber seedlings increased at the start and then decreased with the increase of exogenous selenium concentration. The order of total selenium content in each organ was: root > stem > leaf.[Conclusion] The maximum selenium concentration that cucumber seedlings can stand is 10 mg/L. In the process of production, low concentration amino acid selenium fertilizer(selenium concentration 6-8 mg/L)can be sprayed to cultivate strong cucumber seedlings. [ABSTRACT FROM AUTHOR]