Abstract

Black cumin (Nigella sativa) is a medicinal plant with economic influences, especially in medicine production. The present study investigates the effects of different drip tape and furrow irrigation treatments with normal and deficit irrigations on water use efficiency, various plant parameters and oil content of N. sativa. For this purpose, an experiment with three replications was conducted on a completely randomized block designed. The irrigation treatments consist of three modes of surface drip tape (SDT) irrigation with 50, 75 and 100% evapotranspiration (Et) as well as one mode of surface furrow (SF) irrigation with 100% (Et) requirement of the plant. The highest water use efficiency (1.39 kg/ha/mm) was obtained for drip tape 50% (Et) treatment while the lowest water use efficiency (0.492 kg/ha/mm) was obtained for furrow irrigation treatment 100%(Et). The results showed that seed yield and harvest index was significantly affected by different irrigation treatments (P < 0.01). Additionally, the number of follicles per plant and total yield were also affected by different water treatments (P < 0.05). The results showed, there were no significant effects on plant height, the number of seed per follicle, 1000 seed weight, the number of plants per m² and oil content, based on obtained results, this paper suggests that in different area with prevailing deficit water resources drip tape irrigation 50% (Et) has proven suitable to produce black cumin with high water use efficiency and significant oil content. The results showed that black cumin tolerates water deficiency.

Key words: Nigella sativa, drip tape irrigation, deficit irrigation, water use efficiency.