The effect of irrigation disruption in different stages of growth and the consumed nitrogen on seed yield and yield components of Hashemi Tarom rice (Oryza Sativa L.)

In an attempt to investigate the effect of different moisture treatments and nitrogen levels on the seed yield of Hashemi Tarom rice (Oryza sativ L.), a field experiment was carried out in 2009 in Neka, Mazandaran. The study was conducted in strip split slots with 4 replications following CRBD design. The main factor, i.e. the moisture treatments including waterlogging I1(control), irrigation disruption at tillering stages I2 (15 days), flowering stage I3 (15 days), and the seed filling stage I4 (15 days), and the peripheral factor, i.e. the four nitrogen levels (0, 50, 100 and 150 kg of nitrogen per hectare) in the form urea, were applied. The analysis of variance indicated that the irrigation and nitrogen fertilizer had a significant effect on the seed yield, fertile florets, floret sterility, and the number of fertile tillers. The results of the Duncan test (at P<0.05) revealed that the waterlogging treatment along with the consumption of 150 kg of nitrogen resulted in the highest increase in the total yield and yield components; hence, were placed in group a. Furthermore, it was found that the interaction effect of irrigation and nitrogen levels was significantly different in all of the traits of the fertile florets, the sterile florets, the panicle length, and the fertile tillers. The results indicated that despite the high degree of water consumption, the waterlogging method appears to be the most efficient method for rice irrigation.