Document Type : Research Paper
Authors
1
Master of Science in Irrigation and Drainage, Faculty of Agriculture and Natural Resources, Lorestan University, Khorramabad, Iran,
2
Assistant Professor, Department of Water Engineering, Faculty of Agriculture and Natural Resources, Lorestan University, Khorramabad, Iran
Abstract
Introduction
One of the bottlenecks in today's world is the lack of water for various uses; drinking, industry, agriculture, and environmental needs. The agricultural sector is the largest consumer of water, so it will be the first part which will be damaged by the water crisis. Therefore using methods that increase water productivity or, in other words, increase yield production per unit volume of water is essential. Deficit irrigation is a low cost and simple method for this goal. This research was carried out in order to investigate the effect of deficit irrigation and alternate furrow Irrigation on yield and water productivity of Maize in Khorramabad climate.
Methodology
The treatments consisted of conventional irrigation with 100% water requirement (I100), regulated deficit irrigation with supply of 80% of plant water requirement (DI80), regulated deficit irrigation by applying 60% of plant water requirement (DI60) and using partial root-zone drying (PRD), which was conducted in plots of 18 square meters in a complete randomized block design with three replications at the Research Farm of Faculty of Agriculture and Natural Resources, Lorestan University. The irrigation system of the farm was surface furrow and delivered water to each plot through polyethylene pipes. The volume of water applied to each plot was measured by a volumetric counter.
In this study, the net depth of irrigation was calculated by measuring soil moisture deficiency in the root zone relative to field capacity point. For this purpose, in the days before irrigation, soil samples were taken from the root of the plant in all three replications of control treatment and after weighing, they were placed in the oven and at 105 ° C for 24 hours. After drying, the samples were re-weighed and soil moisture content was determined. At the beginning of the growing season and until June 12, the same irrigation water was applied to all treatments until the plant was fully established and reached a 4 to 6 leaf stage. In fact, until the fifth irrigation, all experimental plots were irrigated equally. After this step and assurance of plant establishment, the research treatments were applied. For the treatment of deficit irrigation using partial root drying (PRD), the calculated water requirement based on 100% water supply was applied to half of the furrows. In the next irrigation event, the remained half was irrigated in the same way.
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