Effect of the Distance between Irrigation Tubes in the Subsurface Drip Irrigation System on Rice Crop Production

Abstract

The water scarcity that Iraq has been experiencing for several years has posed a challenge to agricultural production in general and to rice in particular. Therefore, a field experiment was conducted in the College of Agricultural Engineering Sciences / University of Baghdad, Al-Jadriya region in 2020 to study the possibility of successful cultivation of the rice crop by the dry farming method using the subsurface drip irrigation system and to evaluate the effect of the distance between the T-tape irrigation tubes on some soil characteristics and the production of the rice crop Oryza sativa L. yassamen cultivar , The distance between the irrigation tubes was studied at three levels (10, 15, 20) cm. And study its effect on soil bulk density, soil electrical conductivity EC, panicle length, and grain yield. The results showed that the distance exceeded 20 cm by achieving the lowest apparent soil density of 1.20 g.cm^-3 and the lowest value of the electrical conductivity of the soil EC amounted to 1.76 decimens.m^-1, while the distance of 10 cm excelled by achieving the highest length of the panicle reached 22.5 cm and the highest grain yield reached 3.29 tons.ha^-1 .A 22% decrease in grain yield was noted, which requires developing drought-tolerant and highly productive rice varieties and improving water management by applying smart irrigation. The irrigation water saving rate reached 76%, which allows for the continuity of production of this strategic crop during seasons of water scarcity and the expansion of its cultivated areas. Or providing water to other consuming sectors.