Effects of Organic Fertilizer Complements Application on Grain Yield, Nitrogen Use Efficiency and Milling Properties in two Rice Cultivars (Oryza sativa L.)

In order to evaluate the effects of organic fertilizer complements application (Aminol Forte, Fosnutren and Kadostim) on grain yield, milling properties and nitrogen use efficiency of two rice (Oryza sativa L.) cultivars, a field experiment in factorial layout and a randomized complete block design with 10 treatments and 3 replications was conducted at Rice Research Institute of Iran in 2009. Treatments were fertilizers in 5 levels including: complete chemical fertilizer (for cv. Khazar: nitrogen 90, phosphorus 45, and potassium 75 kg.ha -1; and for cv. Hashemi: nitrogen 60, phosphorus 30, and potassium 50 kg.ha -1, respectively), complete chemical fertilizer + organic fertilizer complements (Aminol Forte, Fosnutren and Kadostim in one Lit.ha-1 as foliar application in tillering, booting and milk stages), 50% of chemical fertilizer + organic fertilizer complements, organic fertilizer complements and control (no fertilizer application), and two rice cultivars (cv. Khazar and Hashemi). After harvest, fissure rate of rice kernels was evaluated after threshing and after paddy drying. Results indicated that fissure rate in Hashemi cultivar was higher than Khazar. The maximum fissure rates were detected in Hashemi cultivar and organic fertilizer complements and control treatments. 50% of chemical fertilizer + organic fertilizer complements had minimum fissure (9.6%). The highest milling recovery obtained in complete chemical fertilizer + organic fertilizer complements treatment (69.2%). The maximum grain yield (5371.1 kg.ha-1) was detected in complete chemical fertilizer + organic fertilizer complements treatment. 50% of chemical fertilizer + organic fertilizer complement treatment showed the highest nitrogen agronomic efficiency (23.3 kg.kg-1) and nitrogen use efficiency (26.4 kg.kg-1). Hashemi cultivar was superior in comparison with Khazar cultivar in all nitrogen efficiency parameters. Results indicated that application of organic fertilizer complements could reduce chemical fertilizers rates and enhanced nitrogen use efficiency parameters.