Comparison of agronomical traits of four rice genotypes (Oryza sativa L.) in cropping systems at Neka region

This research aim was evaluation of rice genotypes in modified systems. An experiment was carried out as split plot in randomized complete blocks design with four replications at Neka region, Mazandaran province, Iran in 2011-2012. Cropping systems were chosen as main plots including conventional, improved and System of Rice Intensification (SRI) and genotypes as sub plots including: Sang Tarom, Hashemi Tarom, Neda and Shiroodi. The result indicated that the most number of fertile tiller per hill, number of spikelet per square meter (374.8 number) and number of filled spikelet percentage per panicle was produced in SRI that has led to the most paddy yield (6412 kg ha-1). The most number of filled spikelet per panicle and filled spikelet percentage per panicle was obtained for cv. Tarom Hashemi. But, number of panicle per square meter (396.8 numbers) was the highest in cv. Neda. The maximum paddy yield equivalent to 7272 and 7315 kg ha-1 was observed for cv. Neda and Shiroodi. The most paddy yield equivalent to 7770 kg ha-1 had produced at interaction of SRI and cv. Neda. Paddy yield in SRI, equal to 5.44 and 12.65 percentage more than improved and conventional system, respectively. Therefore, SRI was the cropping system that with creating optimum management practices has led to increase paddy yield and yield components.