LAUSR

This study was carried out in two growing spring seasons 2017 and 2018 at Kanipanka Agricultural Research Station (Lat. 35°13'12'', Long. 45°25'48'', 550 MASL) in Shahrazoor valley 35 km east of Sulaimani – Iraqi Kurdistan Region to investigate the effect of two irrigation intervals (5 and 10 days) and thirteen different biotic and abiotic treatments on potatoes yield water use efficiency under the field condition. The results showed that the cumulative depth of irrigation in 2017 and 2018 for 5 and 10 days were 369, 228 and 363, 287 mm, respectively, while for both depth of irrigation and precipitation were 535, 394 and 513,437 mm, respectively. The effect of irrigation intervals on the WUE, IWUE and total yield (tons hectare) was significant at 2017 and 2018 season and the average of both seasons, with exception of WUE in the first season. The 5 days irrigation intervals gave the highest values for the second season and the average of both seasons for the character WUE, while 10 days irrigation intervals gave the highest values in both seasons and their average. Regarding the first season and the average of both seasons, the mycorrhizal inoculation treatments gave the highest values of WUE, IWUE and total yield but at the second season, the KCl with Glycyrrhiza glabra (6 g L) extract treatments gave the highest values for WUE, IWUE and total yield.