硼对大豆结瘤和固氮作用的影响——Ⅱ.对根瘤结构和固氮酶活性的影响

在短期无氮营养液栽培条件下研究了缺硼和正常供硼处理对大豆超结瘤突变体(nts382)及其亲本Bragg根瘤结构和根瘤固氮酶活性的影响。结果表明:1.在缺硼条件下,无论是超结瘤突变体nts382,还是亲本Bragg,其根瘤固氮酶活性都显著下降;2.无论是缺硼还是正常供硼处理,超结瘤突变体nts382单位鲜重根瘤活性都明显低于亲本,但由于nts382每株根瘤数和鲜重显著高于其亲本,使每株固氮酶活性明显高于亲本,植株中氮素积累总量也相应的高于亲本;3.缺硼条件下,根瘤细胞结构发生明显改变,细胞壁凸凹不平,细胞间隙加大,含菌细胞内类菌体含量减少。这可能是硼影响根榴细胞正常固氮功能的主要原因。

EFFECT OF BORON ON GROWTH, NODULATION AND NITROGEN FIXATION OF SOYBEAN NODULATING MUTANTS AND ITS PARENT Ⅱ. Nitrogenase activity and nodule structure

This study was undertaken to determine how boron might affect the nodulation and nitrogen fixation in a short term hydroponically cultured soybean supernodulating mutant nts382 and its parent Bragg cv. in N free solution. The results indicated that nitrogenase activity decreased significantly in both soybean genotypes under boron deficiency. In boron free culture medium, nodule cell walls changed obviously and cell arrangement was irregular, suggesting the importance of boron in the stability and normal functionality of nodule cells.