硒和丛枝菌根真菌处理对苋菜生长及硒积累的影响

Effects of Selenium and Arbuscular Mycorrhizal Fungi Applications on Growth,Photosynthesis,and Selenium Accumulation of Amaranthus tricolor L.

【目的】探明丛枝菌根真菌(Arbuscular mycorrhizal fungi,AMF)在苋菜富硒栽培中的生物效应,综合评价AMF对不同硒形态处理下苋菜生长和硒积累的影响。【方法】采用盆栽试验,分析了土施外源硒和接种AMF对苋菜光合作用、生长状况、苋菜红素以及硒积累的影响。【结果】硒酸钠、亚硒酸钠和L-硒代半胱氨酸处理均降低了苋菜红素含量,但对菌根侵染率和菌根依赖性均无显著影响,同时显著提高了苋菜叶片叶绿素a、b含量、蒸腾速率(T_(r))、气孔导度(G_(s))、净光合速率(P_n)和胞间CO_(2)浓度(C_(i)),其中L-硒代半胱氨酸处理效果最佳,说明外源硒处理对苋菜的生长有一定的正效应。另外,接种AMF对不同硒处理下苋菜的生长也有促进作用,且提高了叶片苋菜红素含量,同时增强了光合能力和根茎叶硒含量的积累。【结论】接种AMF和外源硒处理均能提高苋菜的光合能力和硒积累能力,从而促进苋菜生长和提高苋菜营养品质,两者交互处理可作为提高蔬菜富硒栽培的有效措施。

【Objective】Amaranth cultivation enriched by applications of selenium and arbuscular mycorrhizal fungi(AMF)was investigated.【Methods】In a pot experiment,selenium and AMF were added to the soil in cultivating Amaranthus tricolor L.seedlings.Effects on the photosynthesis,growth,and selenium accumulation of the plants were monitored.【Results】The selenium treatment significantly increased the contents of chlorophyll a and b,transpiration rate(T_r),stomatal conductance(G_s),net photosynthetic rate(P_n),and intercellular CO_(2) concentration(C_i) but reduced the amaranthine and not significantly affected the infection rate of or dependence on the mycorrhizae of the seedlings.On the other hand,AMF along with the application of various selenium compounds promoted the amaranth growth and increased the leaf amaranthine content,photosynthetic capacity,and selenium accumulation in the roots,stems and leaves.【Conclusion】Combined AMF and selenium applications benefited the photosynthesis and nutritional quality of A.tricolor.