关键词: 氮素效率, 氮肥, 管理模式, 光能利用率

Abstract: Using test tube-slide method to culture plants, the aerial nodules are successfully bred onshoots of C.cunninghamiana seedlings.The pricked and non-pricked sites on stem are inoculated with Frankia strain Cool which was isolated from root nodules of same plantspecies.and the aerial nodules are appeared 40 days after,which arise from the pericycleof stem.The lobes of aerial nodule are similar to those of root nodules in size and shape,and each lobe has a nodule root at its top.Transverse section of aerial nodule shows thatthe endophyte hyphae have diaphragm and some hyphae pass through two plant cells.Histological characteristics of aerial and root nodules do not show significant differences.The aerial nodules have a mean ARA value (n mol C₂H₄·min^-1·g^-1 fresh weight ofnodules) of 28.79, compared to 81.96 of their root counterparts.The nitrogenase activities of both aerial and root nodules can be reduced by low concentration of NH₄⁺(0.47g·L^-1 NH₄)₂SO₄) and inhibited by 2.0g·L^-1(NH₄)₂SO₄.

Key words: Aerial nodules, Nitrogen fixation, Casuarina cunninghamiana, nitrogen efficiency, nitrogen fertilizer, management mode, light use efficiency