potato water Use efficiency analysis on farms in the north of Khuzestan province

Annual evaluation of water use efficiency index provides the possibility of extracting strategies to improve farm water productivity. The main purpose of this article is to determine the effective factors in improving the water productivity of potatoes in the north of Khuzestan province. In Khuzestan province, potato cultivation has started from the first 10 days of October as winter planting or continuation plan with the aim of supplying the potatoes needed by the market, and will end until the first 10 days of February. The present paper is the result of studying on growing stages, management of surface-furrow irrigation and potato yield in 33 selected farms in different water supply sources including Dez and Gotvand’s irrigation and drainage networks, wells and pumping during one growing season. In this study, it was found that with an average effective rainfall of 201 mm and a volume of water consumption of 2135 cubic meters per hectare, 21100 kg of potato tubers with water use efficiency (effective rainfall + irrigation) 5.41 kg per cubic meter is produced. The average water application efficiency in these farms was 39.3%. Improper irrigation cycle and soil moisture caused most fields with delayed sowing dates, especially in the middle growth stage. Based on the analysis of farmers' managements, practical recommendations were provided to increase the water use efficiency of potatoes by selecting the appropriate planting date, timely irrigation management, observing the harvest time in proportion to the maturity of potato tubers and if possible change in irrigation method.