丛枝菌根真菌与根瘤菌接种对大豆根瘤分布及磷素吸收的影响

在温室条件下,采用石英砂盆栽试验研究了大豆(冀豆6号)接种丛枝菌根真菌（Glomous mosseae）与根瘤菌 （Bradyrhizobium japonicum）对根瘤的形成、分布以及磷素吸收效率的影响。结果表明,大豆生长至开花期（接种后56 d）,与单接种根瘤菌处理相比,双接种AM真菌和根瘤菌显著增加大豆生物量、氮、磷含量、根系上的总根瘤数。单接种根瘤菌条件下,总根瘤数的48.4%分布在主根上,51.6%分布在侧根上;根瘤菌与AM真菌双接种时,总根瘤数的32.5%分布在主根上,67.5%分布在侧根上。双接种处理的侧根根瘤的固氮酶活性显著高于单接种处理的。双接种条件下大豆侧根中AMF侵染增强,尤其是结根瘤侧根上的AM真菌的侵染率高于未结瘤的侧根的菌根侵染率。接种后28 d单接种菌根真菌处理显著高于双接种处理的植株磷的吸收效率;而56 d 时趋势相反。以上结果表明,AM真菌侵染改变根瘤在大豆根系上的分布,根瘤数量、分布与结根瘤侧根上AM真菌的侵染强度存在正相关关系。

Effects of inoculations of Glomus mosseae and/or Bradyrhizobium japonicum on formation and distribution of nodules and phosphorus uptake of soybean

A pot experiment was carried out to investigate the effects of inoculation of Glomus mosseae(GM) and/or Bradyrhizobium japonicum(BJ) on the formation and distribution of nodules and phosphorus uptake efficiency of soybean at the 28th and the 56th day after inoculation.The results showed that at the 56th day after inoculation,compared with the treatment BJ inoculation,the plant biomass,P and N concentrations,the number of lateral roots with nodules,nodules on lateral roots,were increased in the treatment of GM and BJ inoculation.With BJ inoculation,the total nodule number in the taproots and lateral roots were 48.4% and 51.6%,respectively;while with both GM and BJ inoculation,the number in the taproots and lateral roots were 32.5% and 67.5%,respectively.The nitrogenase of the treatment with both GM and BJ inoculation was higher than each of the single inoculation treatment.The AMF inoculation rate of the treatment with both GM and BJ inoculation was increased,especially that in the lateral roots with nodules was higher than that without nodules.On the 28th day after inoculation,the phosphorus absorption efficiency of AM inoculation treatment was higher than that with double inoculation treatment;while on the 56th day after inoculation,the phosphorus absorption efficiency in the treatment of double inoculation was higher than each of the single inoculation treatment.In conclusion,AMF inoculation changed the distribution of nodule in the roots,which was positively related with the AMF inoculation.