Effects of Organic and Chemical Fertilizers on Yield and Yield Components of Rice in Different Moisture Stress Conditions

Organic fertilizers contribute to the optimal growth and yield of crops, consumers' health, and more resistance to water deficit by providing the plants with proper concentrations of nutrients. So, two separate trials were conducted in flood and stressful conditions as split plots based on a randomized complete block design with three replications. The experimental factors included N fertilizer at three levels of 50, 100, and 150 kg ha(-1), pelletized chicken manure at three levels of 1250, 2500, and 3750 kg ha(-1), and cattle manure and urban waste compost, each at three levels of 3750, 7500, and 11,250 kg ha(-1) as the main plot and cultivar at two levels of "Gilaneh" and "Hashemi" as the sub-plot. Results showed that cv. "Gilaneh" treated with 3750 kg ha(-1) pelletized chicken manure produced the highest paddy yield in both flood and drought conditions (7399 and 7191 kg ha(-1), respectively). The unfertilized "Hashemi" produced the lowest paddy yields of 4035 and 3009 kg ha(-1) in flood and drought conditions, respectively. It seems that the application of organic fertilizers instead of chemical fertilizers is more effective in increasing grain quality. The fertilization management to accomplish the highest grain quality differs between flood and drought conditions.