Increase in growth, productivity, nutritional status of Rice (Oryza sativa L.) and enrichment in soil fertility applied with Azospirillum and nitrogen level

Field experiments were conducted to Influence of different levels of nitrogen and Azospirillum inoculation on direct-seeded rice in a Vertisol, during kharif season of 2015 at Department of Soil Science and Agricultural Chemistry, JNKVV, Jabalpur. The experiment was laid out under randomized block design (RBD) with 3 replications and 8 treatments namely (unfertilized+uninoculated (UFUI), recommended dose of nitrogen 50%+uninoculated (RDN50%+UI), RDN75%+UI, RDN100%+UI, UF+Azospirillum (UF+Azosp.,), RDN50%+Azosp., RDN75%+Azosp and RDN100%+Azosp.,). It was observed that significant improvement was noticed in yield attributes and soil properties. The response from the treatment of RDN100% +Azosp., was found statistically best to increase available nitrogen (N) content in soil at 45 DAS and at harvest of the crop by 29% and 27%, respectively and N content in the plant, grain and straw by 46%, 50% and 55%, respectively over the control of UFUI. Similarly, trend was significantly enhanced total N uptake by crop with 129% over the control of UFUI. While, same treatment combination increasing azospiral population in rhizospheric soil at 45 DAS, 65 DAS and at harvest by 2.28, 2.07 and 2.05 log folds, respectively over the control of UFUI and enhanced yield attributes and yields of grain and straw of rice with 113 and 58%, respectively over the control of UFUI. While the treatment RDN100%+Azosp., exhibited numerically higher values but was statistically at par to RDN75%+Azosp.