Investigating the effects of cultivation dates and irrigation systems on some agronomic properties of rice in Gonbad Kavous

In order to evaluate the performance of sub-irrigation system using porous clay capsules, the experiment was conducted as factorial plot in base of randomized complete block design with three replications and two irrigation treatments on two different time, 21-MAY-2016 and 21-JUNE-2016 for rice culture. In this study some morphological traits including grain yield, number of empty seeds, number of filled seeds, number of whole seeds, weight of main panicle, main panicle length, 1000-grain weight, plant height, water consumption and water use efficiency were assessed. The results showed that flooding irrigation had no significant effect on the yield increasing compared to sub-irrigation at two sowing dates. Also, the water consumption decreased 30% and 39.5% using sub-irrigation in two sowing date (21-MAY-2016, and 21-JUNE-2016) respectively, comparision to flooding irrigation. Based on the result grain yield at two sowing date had significant effect. The grain yield decreased 28 percent in the second date of culture (4463 kg.ha-1) compared the first date of culture (3212 kg.ha-1) at two irrigation methods. Generally, using porous clay capsules technique, rice culture could be provided without yield loss at arid and semiarid reigons.