اثر مصرف سیلیس و تنش نیتروژن بر شاخص‌های خوابیدگی برنج رقم طارم محلی

In order to investigate effect of nitrogen stress and silicon application on morphological and agronomical traits and grain yield of rice var. Tarom Mahalli, an experiment was carried out at split plot in randomized complete blocks design with three replications at Sari, Mazandaran, Iran in 2012. Main plots was silicon rates including 0, 250, 500 and 1000 kg/ha calcium silicate of and sub plots was nitrogen stress in four growth stages including {start of transplanting (based), start of tillering stage, initial panicle stage and heading stage}. Results showed that the highest fourth inter-node bending moment equivalent to 1742 and 1777 g/cm was observed with application of 500 and 750 kg silicon ha, but the least fourth inter-node bending moment 1577 and 1317 g/cm was obtained with control and 250 kg/ha silicon application. With increase silicon application compare to control stem hemi cellulose content was increase. The most grain yield 657.3 g/m2 was produced with 1000 kg/ha silicon application. The most fourth inter-node bending moment was observed with nitrogen stress at heading stage. The highest stem cellulose and lignin content was obtained for nitrogen stress at heading stage. The maximum grain yield 587.3 g/m2 was produced in nitrogen stress at based stage. Therefore, 750 kg/ha silicon application was the best silicon treatment, and start of tillering and initial heading because of decrease grain yield was the sensitive rice growth stage.