Effect of different strains of bradyrhizobium and two types of vesicular arbuscular mycorrhizas (vam) on biomass and nitrogen fixation in Vigna Radiata (L) wilczek var. NM 20-21

Effect of three strains of Bradyrhizobium (VR16, Vr 17 and Vm 1) and two VAM species (Glomus mosseae Nicol. and Gerd., and an unknown species ME) on biomass, acetylene reducing activity (ARA) of modules and nitrogen content of shoots in Vigna radiata (L.) Wilczek var. NM 20-21, using nitrogen free nutrient solution, was studied. Plants inoculated with Vr16 or Vm1 showed greater biomass of shoots as compared to Vr17 or Vr16+Vr17+VM1 inoculated plants. Biomass of Vr17 inoculated plants was increase by mycorrhizal inoculation while other treatments i.e., Vr16, Vm1 or Vr16+Vr17+Vm1 showed negative response to mycorrhizal inoculation. ARA of nodules and nitrogen content per gram dry weight of shoots were different in different treatments of Bradyrhizobium. ARA and nitrogen content of plants inoculated with Vm1 or mixture of Bradyrhizobium strains (Vr16+Vr17+Vm1) was increased on mycorrhizal inoculation. (author)