investigation of different irrigation systems and water management on yield and water use efficiency of black cumin

ِdfferent drip (surface and subsurface) and furrow irrigation methods effects on grain, oil and water use efficiency based on grain black cumin(nigella sativa l.) as medicinal plants was investigated. for this purpose, experiment over the past two years (2009 and 2010) in a randomized complete block was designed in three replications. treatments in this research were consisting of 50, 75 and 100% of black cumin annual water requirement with different drip irrigation methods consist of (surface and subsurface) and also the furrow irrigation treatments. the results of this research showed significant effects of different levels of water stress on different plant parameters such as: grain, oil and water use efficiency in both years of study. the highest and lowest oil percentage was belonging to different treatments 100% of subsurface drip tape irrigation and 50% of surface drip tape irrigation systems with 30.6 and 29.2% respectively. the highest and lowest average water use efficiency based on seed yield were obtained as 1.67 and 0.96 kg/ha/mm for 50% of subsurface and furrow irrigation treatments, respectively. the results of this investigation also showed that by using of subsurface drip irrigation method and by applying of 50% of black cumin annual water requirement, the highest grain water use efficiency could be obtained.