摘要
恒定磁场处理慢生大豆根瘤菌“005”和接种后的大豆植株,发现磁场可以提高根瘤的固氮活性。在一定的磁场强度(70—100mT)下,固氮活性平均可以提高4—5倍,植株的结瘤数和根瘤重量平均提高2—3倍。从这样的根瘤中所分离出的根瘤菌,由慢生型转变成快生型,在100植株中有17株的根瘤分离出快生菌。生长世代时间和培养溶液中的pH值与慢生型不同,而与快生型相同。
Treatment of slow growing Bradyrhizobium japonicurn “005” and inoculated plants with consistant magnetic field revealed that the efficiency of nitrogen fixation could be increased by 4—5 times under an appropriate magnetic intensity.The average number and weight of root nodules per experimental group were also increased by 2—3 times respectively.The change in growth phenotype of rhizobia isolated from the nodules of treated plants showed that the fast growing type of Rhizobium appeared with the frequency of about 17% among I00 plants. The generation time and pH value of the fast growing isolates obtained were similar to those of Rhizobium USDA 191 but different from Rhizobium“005”.The magnetic field effect on ni trogenase activity and the change of growing rate of Rhizobium are also discussed.
关键词
磁场
大豆
根瘤菌
固氮
Magnetic field
Soybean
Rhizobium
Nitrogen fixation
