氮锌复合作用对白三叶草根瘤超显微结构的影响*

 采用砂培试验和电子显微技术，研究了不同水平氮锌配施对白三叶草根瘤发育和超显微结构的影响。结果表明，随施氮水平增加，根瘤数量、根瘤固氮酶活性、单瘤重量、根瘤细胞内类菌体数量显著下降，类菌体周膜空间增大。与缺锌条件相比，足量供锌显著增加了根瘤数量、单瘤重量、根瘤固氮酶活性、根瘤细胞内类菌体数量和类菌体体积，减小了类菌体周膜空间，类菌体周膜、细胞壁、细胞膜完整性和均匀性增加。与其它处理相比较，低氮和足量供锌处理显著增加了根瘤数量、单瘤重量、根瘤固氮酶活性、根瘤细胞内类菌体数量，显著减小了类菌体周膜空间。

Compound Effects of Nitrogen and Zinc on Nodule Development and Ultrastructure of White Clover

Sand culture experiment, electron microscopy technique were used to investigate the compound effects of nitrogen and zinc on nodule development and ultrastructure of white clover. The main findings showed that the number, nitrogenase activity, single weight, bacteriod number of nodule significantly decreased, peribacteriod membrane space (PBS) enlarged with the increased application of nitrogen. Compared with zinc deficiency condition, sufficient zinc supply significantly increased the number, nitrogenase activity, single weight, bacteriod number and volume of nodule, remarkably decreased PBS, as well as increased integrity and uniformity of peribacteriod membrane (PBM) , cell membrane and cell wall of nodule. When low rate nitrogen and suficient zinc applied together, there were synergism effect on the increase of the number, single weight, bacteriod number and volume, nitrogenase activity of nodule, the reduction of PBS as well as the conservation of the integrity of PBM and cell membrane.