Effect of Locally Made Riser Type and Operating Pressures of the Fixed Sprinkler Irrigation System on Some Soil Characteristics and Maize Yields

Abstract

A field experiment was conducted during growing season of 2021, to evaluate the effect of the types of locally made riser and the operating pressures of the fixed sprinkler irrigation system on some soil characteristics and the production of maize crop at Al-Raed Research Station located in the Akkarouf area on the Abu Ghraib-Shoala Road, one km north of the highway (Baghdad - Anbar). The soil texture was silty clay loam. Two factors were used in the experiment, namely the type of risers, which included three levels: a normal riser, automatic inner tube, and automatic external tube, and the operating pressures have three levels included: 1, 1.5 and 2 bar. The following characters were studied, which are the amount of water used during the season, moisture uniformity coefficient, soil penetration resistance, and maize yield. Nested design under randomized complete block design (RCBD) was used with three replications, and the least significant difference under probability (0.05) was used to compare the averages of the treatments. The results indicates that the automatic inner and external tube outperformed the normal riser in the amount of water used during the season, which amounted to 90 m3, and also the automatic external tube outperformed in obtaining the highest moisture uniformity coefficient of 82.8% and the lowest soil penetration resistance stood 2.63 kg. cm-2, and the highest grain yield stood 6.38 tons. ha-1. As well as, the superiority of the operational pressure of 1 bar in the amount of water used during the season stood 81 m3. Season-1, and the superiority of the operational pressure of 2 bar with the highest value of the moisture uniformity coefficient amounted of 82.15%, and the lowest soil penetration resistance stood 2.67 kg. cm-2 and the highest crop yield stood 6.46 tons. ha-1. The two-way interaction between the self-propelled reed with inner tube and the operating pressure of 1 bar exceeded the minimum amount of water used during the season, which amounted to 79 m3. The two-way interaction between the automatic inner tube with the operating pressure of 1 bar outperformed with minimum amount of water used during the season, which was 79 m3 season-1. While the two-way interaction between automatic external tube and the operating pressure of 2 bars exceeded the highest value of the moisture uniformity coefficient stood 85.35%, and the lowest value of soil penetration resistance stood 2.54 kg.cm-2, and the highest crop yield stood 6.89 tons. ha-1. The results also indicate the success of using the locally designed and made "self-rising" riser according to the plant's height and used in the fixed sprinkler irrigation system to irrigate the maize crop.