Effects of arbuscular mycorrhizal colonization on ammonium-N uptake activity of the host plant.

摘要

The effect of arbuscular mycorrhizal colonization (AMC) on ammonium-N uptake in the symbiotic system of marigold (Tagetes patula) and Glomus etunicatum was investigated. T. patula was cultivated in pots with five treatments at different P and N application rates, with or without AMC. After growing the plants for 29 days, 15N-ammonium was applied to each treatment, and after a further 24 h plants were sampled for analysis. To evaluate the ammonium-N uptake of plant roots, the specific absorption rate of ammonium-N (SAR-AN: g N/kg root dry weight per day) was determined. At low P and N application rates, AMC increased plant P content and reduced plant N content. The SAR-AN of T. patula decreased with an increase in plant P content due to AMC. The SAR-AN also decreased with an increase in plant dry weight, but increased with an increase in plant N content. 15N translocation from roots to shoots was depressed by AMC.