金线莲施硒的吸收与积累规律

Absorption and accumulation rules of selenium in Anoectochilus roxburghii

为探究金线莲的硒吸收、转化及生长效应,通过种苗繁殖培养基、移栽基质、林下腐殖土添加与叶面喷施等方式进行亚硒酸钠(Se^(4+))施用试验,检测分析金线莲植株形态、主要成分、植株及器官总硒与有机硒、生长量等指标与硒施用量关系。结果表明,施硒能极显著提高金线莲植株含硒量,硒吸收利用率最高为繁殖培养基添加方式,为13.09%,其他依次为叶面喷施、基质添加和林下腐殖土添加方式,分别为6.81%、6.36%和2.79%。植株干品总硒含量随施用浓度提高而增加,有机硒含量为81.8%~92.1%,硒有机转化率不受施用浓度影响。植株各器官硒含量为根>叶>茎,硒有机转化率为叶>根>茎。根部适宜浓度施用硒能促进金线莲植株生长,过高浓度施用抑制生长。叶面喷施硒对金线莲植株生长量无显著影响。施硒对金线莲植株主要成分含量无显著影响。金线莲的硒最佳经济施用量分别为培养基添加4.75 mg/L、叶面喷施0.168 mg/株、基质添加8.00 mg/L、林下腐殖土添加9.50 mg/L。综合各种施用方式效果来看,以种苗繁殖培养基添加硒方式可获得最佳吸收利用率和最佳产量效应。

The objectives of this study were to understand the effects of selenium application on the selenium accumulation and transformation from inorganic to organic form in Anoectochilus roxburghii and the influence of selenium on its growth.Sodium selenite application test was conducted by adding to seedling propagation medium,transplanting substrate,humus soil under the forest and by foliage spraying,and then the relationship between the indexes of the shape and main components of A.roxburghii,total selenium and organic selenium of plant and organs,growth amount of plant and selenium application amount were detected and analyzed.The results showed that selenium application significantly increased the selenium content of the plants and the highest absorption and utilization rate of selenium was 13.09%for adding to seedling propagation medium,followed by foliage spraying,adding to transplanting substrate and humus soil under the forest,which were 6.81%,6.36%and 2.79%,successively.The total selenium content of dry plant increased with the application concentration,the organic selenium content was 81.8%-92.1%,and the selenium organic conversion rate was not affected by the application concentration.The selenium content in each organ of the plant ranked as root>leaf>stem,and the conversion rate of organic selenium in plant organs ranked as leaf>root>stem.The proper concentration of selenium applied to the root could promote the growth of A.roxburghii,while excessive concentration could inhibit its growth.Foliage spray selenium had no significant effect on the growth of the plants.Selenium application had no significant effect on the content of main components in the plants.The best economic application amount of selenium in the plants of A.roxburghii was 4.75 mg/L in seedling propagation medium,0.168 mg/plant in foliage spraying,8.00 mg/L in transplanting substrate and 9.50 mg/L in humus soil under the forest.From the comprehensive application effect,the best absorption and utilization efficiency and the best yield effect could be obtained by adding selenium to the seedling propagation medium.