Effect of inoculation methods of Mesorhizobium ciceri and PGPR in chickpea (Cicer areietinum L.) on symbiotic traits, yields, nutrient uptake and soil properties

Inoculation effects of Mesorhizobium ciceri (CH-1233) and PGPR (Pseudomonas sp., LK-884) alone and in combinations with different methods (seed treatment, furrows application by mixing with soil and vermicompost) in chickpea (Cicer arietinum L.) were compared during rabi season of 2008-09 at Pantnagar. Mesorhizobium sp. and PGPR alone inoculation significantly increased nodule number, by 44.3 and 34.4, nodule dry weight, by 46.1 and 33.2 %, and plant dry weight, by 33.6 and 42.4 %, over uninoculated control. Their co-inoculantion gave significant increases in nodule number of 16.5 % over PGPR alone and in nodule dry weight of 36.4 % over Mesorhizobium sp. alone inoculation. This treatment also significantly improved the plant dry weight by 11.5% over Mesorhizobium sp. alone inoculation. Mesorhizobium sp. alone recorded significant increase in grain yield of 11.8 % and PGPR alone in grain and straw yields of 15.3 and 14.9 % over uninoculated control. Their dual inoculation resulted in significant increase only in straw yield of 16.6 % over Mesorhizobium sp. alone. Co- inoculation of Mesorhizobium sp. and PGPR also significantly increased N uptake by straw and available P, dehydrogenase activity (DHA) and microbial biomass carbon (MBC) in soil over Mesorhizobium sp. alone inoculation. Inoculants applied in furrows mixing with soil and vermicompost resulted in better nodulation than seed treatment. These treatments also recorded significantly more N uptake of 17.7 and 14.5 % and P uptake of 12.5 and 16.0 % by straw over seed treatment, respectively. Application of inoculants in furrows by mixing with soil was better than that mixing with vermicompost by recording significantly more available P, DHA and MBC in soil than seed treatment.