Effects of different irrigation regimes, biological and nitrogen fertilizers on grain yield and some physiological traits of two rice (Oryza sativa L. cv. “Hashemi and Gilaneh”)

In order to evaluate the effects of irrigation regims and nitrogen biological and chemical fertilizers on grain yield (paddy) and some physiological traits, an experiment was conducted in the form of split split plots in a randomized complete block design with three replications in two years ( 2017 and 2018). It was carried out in a research farm of the National Rice Research Institute of I. R. Iran in Rasht. Experimental factors include irrigation regime at three levels without stress (permanent flooding) and irrigation intervals of 10 days and 15 days as the main factor, fertilizer at three levels including inoculation of seedlings with biofertilizer, inoculation of seedlings with biofertilizer + 50% fertilizer Chemical nitrogen required by the plant and 100% chemical nitrogen fertilizer required by the plant) as a secondary agent and rice cultivar at two levels including Hashemi and Gilaneh as a secondary agent. The highest grain yield in the first year (4.14 t/ha) and the second (3.99 t/ha) was recorded in the treatment of 100% of the chemical fertilizer supplying the plant with nitrogen requirements, flooding conditions and Gilaneh cultivar, which was treated with inoculation Transplant roots with biofertilizer + 50% of chemical fertilizer supplying nitrogen required by the plant (combined treatment) in the first year (3.93 t/ha) and the second (3.85 t/ha) were in a statistical group. Consumption of biofertilizer along with chemical nitrogen fertilizers, in addition to producing sufficient yield and improving the efficiency of nitrogen uptake, was able to reduce the use of nitrogen chemical fertilizers by 50%.