Saman M. Karim - Department of Natural Resources, College of Agricultural Engineering Sciences, Sulaimani University, Iraq
Tariq. H. Karim - Department of Soil and Water, College of Agricultural Engineering Sciences, Salahaddin University, Iraq

To increase food and nutritional demands of the growing population, a significant part of agricultural research should focus on improving water use efficiency. Few studies have involved the simultaneous use of mulch and deficit irrigation in the semiarid environment to conserve water without yield penalties. Accordingly, a field experiment was conducted over a silty clay soil at the outskirt of Sulaimani, Iraqi Kurdistan region during the summer season of ۲۰۲۱ to evaluate the impact of deficit irrigation levels [(۱۰۰%, ۸۰%, ۶۰ and ۴۰% of full irrigation (FI)] and straw mulch (with and without) on seed yield, quality traits of sesame, Sesamum indicum L. besides its water use efficiency. The results indicated that there was a steady decrease in sesame with a decrease in the amount of applied water with and without mulch. The water use efficiency increased by water deficit level from ۱۰۰ to ۶۰% of FI and declined at ۴۰% of FI with and without mulch. Mulch offered a better performance compared to no mulch in terms of crop yield, water use efficiency and oil content. The crop response factor (ky) values were ۰.۸۴۹ and ۰.۷۸۵ with no- and with- mulch respectively. Based on these findings, it is recommended to apply deficit irrigation in combination with mulching practice   as an approach of water savaging for agriculture in regions with limited water resources.

Sesame, Deficit irrigation, Water Use Efficiency, Crop response factor, Mulching