大豆根毛对大豆根瘤菌的生化吸附及其对结瘤影响的研究

本文研究证明大豆根毛与大豆根瘤菌具有专化性生化吸附作用。吸附主要发生在根毛端部。同一棵根上不是所有的根毛都能发生生化吸附,吸附与根毛的生长令期有关。用13种大豆根瘤菌株系与7个大豆品种根毛生化吸附实验表明,吸附率明显地存在有差异性,但这种差异与结瘤量无相关性。使用本研究发现的生化吸附率高而不能结瘤的1.174大豆根瘤菌株系与吸附率较低而结瘤力强的113—2或61A67大豆根瘤菌株系双接菌,证明能明显降低113—2或地61A76的结瘤量,表现出大豆根毛生化吸附具有竞争性抑制大豆根瘤菌的侵入、结瘤作用,对理论研究和实际应用具有一定重要意义。

STUDIES ON THE ADSORPTION OF Rhizobium japonicum TO SOYBEAN ROOT HAIRS AND THE ADSORPTIVE EFFECTS FOR NODULATION SYMBIOSIS

It is demonstrated in this paper that the adsorption of specificity between soybean root hairs and Rh. iaponicum occurs mainly on the tip area of root hairs. The adsorption occurs on some of the root hairs, not on the all. And it is releted to the growth phase of root hairs. 13 strans of Rh. japonicum and 7 varieties of soybean were used for these tests. These results showed that the adsorptive rates of root hairs presented obvious difference, but these differnces, were not related to nodule quantity. Inoculated onto seedlings were both of Rh. japonicum 1. 174 with its highest adsorptive rate in the test while no nodule formed and Rh. iaponicum 113--2 (or 61A76) with its Iower adsorptive rate and high ability of nodulation. The seedlings were cul- tured in a solution containing mineral nut rients. These results showed that the nodule quantity was decreased. Obviously the adsorption may play a role for inhibiting the ifnection and nodulation of rhizobia.