Effect of Irrigation Regimes on Crop Water Use Efficiency of saffron (Case study: theBakharz region of Khorasan Razavi, Iran)

An experiment was conducted in a strip-plot layout based on a randomized complete block design with three replications in the 2016-2017 growing season at the Bakhrez county, Khorasan Razavi province, Iran in order to study quantitative performance and water use efficiency of a few saffron criteria in response to different irrigation volumes and intervals. Irrigation intervals was allocated as horizontal factor (factor A) in four levels (a1=15, a2 =30, a3 = 45, and a4 = 90 days) and irrigation water volume performed as vertical factor (factor B) in four volumes (b1 = 250, b2 = 500, b3 = 1000 and b4 = 1250 m3.ha-1). The results showed that the highest saffron flower and corm yields were obtained in the a2b3 treatment (total water volume of 6000 m3.ha-1). The highest reduction in corm yield is shown in the a4b1 treatment (total water volume 750 m3.ha-1) with a decrease of 72.1% compared to a1b2 (total water volume 5500 m3.ha-1). The lowest fresh flower yield was obtained in the a4b1 treatment (total water volume 750 m3.ha-1) with a decrease of 76.5% compared to a1b2 (total water volume 5500 m3.ha-1), and the lowest yield of corm yield was shown in treatment with a4b1 volume (total water volume 750 m3.ha-1) with a decrease of 70.6% compared to the a2b3 volume (The total volume of water was 6000 m3.ha-1). Also, the results showed that the highest decrease in corm water use efficiency was obtained in the a1b4 treatment (total water volume 13750 m3.ha-1) decreased by 85.4 percent compared to a3b1 (total volume of water 1000 m3.ha-1) and the greatest decrease in fresh flower water use efficiency was shown in the a1b4 treatment (total volume of water 13750 m3.ha-1) decreased by 82.4% compared to a2b1 (total volume of water 1500 m3.ha-1). According to the results, the use of 250 to 500 m3.ha-1 irrigation in 30-day intervals (1500 to 3000 m3.ha-1) is recommended for maximum water use efficiency in saffron cultivation.