Effect of different methods of inoculations with a native plant growth promoting bacteria on some vegetative characteristics and yield of rice (cv.  Tarom Hashemi') under different levels of potassium fertilizer

This study aimed to investigate the effect of a native plant growth promoting bacteria (Enterobacter sp.) on some vegetative characteristics and grain yield of rice (cv. ‘Tarom Hashemi’) in Babol city in 2016. These experiment was arranged in a split plot based on a randomized complete block design with three replications. Six levels of potassium sulfate fertilizer (PSF: zero, 25, 50, 75, 100 and 125 kg ha-1) were used as the main plot and four levels of inoculations (non-inoculation as control, seed inoculation in the seedbed condition, seedling root inoculation before transplanting time, combined both previously methods) served as the sub-plots. The results indicate that various methods of inoculation increased plant height (PH), tillers number per hill (TNH), total leaves number per hill (TNL), leaf area index (LAI) and grain yield (GY) of rice by 1.25-2.54, 11.7-16.5, 12.5-14.2, 7.16-17.9 and 14.6-19.8%, respectively, compared to the control condition. Rice plants treated with Enterobacter sp. also reached to the anthesis stage about one day sooner than the control. In this study, the studied traits significantly influenced by PSF and various methods of inoculation, although their interaction were not significant. Among inoculation methods, the combined method was better than others. In addition, values of all studied traits such as PH, TNH, TNL, LAI and GY (18.2% more than the control) increased as PSF increased from zero to 125 kg ha-1. Consequently, the application of Enterobactersp. and PSF through improved the vegetative characteristics, resulted in an increase in light absorption and improved GYof rice.