A field experiment was carried out at Pantnagar during 2005-06 to examine the interaction between 10 rhizospheric bacteria isolates with Mesorhizobium ciceri on nodulation, growth, yields and nutrient uptake by chickpea (Cicer arietinum L.). The experimental soil was sandy loam of pH 7.2 having 5.2 mg/kg Organic C, 140.2 kg/ha available N, 16.1 kg/ha available P and 282.5 kg/ha available K. The test crop variety was Pant G-186. Inoculated Mesorhizobium sp. alone, irrespective of rhizobacteria, increased the number and dry weight of root nodules numerically, by 23.2 and 23.1 % and plant dry weight significantly, by 3.2 % over uninoculated control at 60 DAS. It also gave numerical increases of 11.2 % and 13.0 % in grain and straw yields, 26.1 and 29.8 % in N uptake and 21.2 and 30.3 % in P uptake by grain and straw, respectively. Different rhizobacteria, irrespective of Mesorhizobium sp., gave increases of 77.2 to 58.7 % in nodule number and 13.3 to 65. % in nodule dry weight at 60 DAS, 20.0 to 57.7 % in grain yield, 12.9 to 44.1 % in straw yield, 17.8 to 85.4 % in N uptake by grain, 15.0 to 46.6 % in N uptake by straw, 5.5 to 63.8 % in P uptake by grain and 14.8 to 61.9 % in P uptake by straw over no rhizobacteria inoculation. All rhizospheric bacteria, except LK-754, LK-786, PUK-791 and KB-133 improved the grain and straw yields significantly. All rhizospheric bacteria, except LK-754, also recorded significantly more microbial biomass C, dehydrogenases activity and acid phospahatase activity in soil over no rhizobacteria inoculation. Interaction between the Mesorhizobium sp. and rhizobacteria with was not significant. PUK-171 was found to be the best for most plant growth and yield and soil health parameters.

Keyswords: Mesorhizobium; Rhizobacteria; Microbial biomass carbon.