Black cumin plants were studied to see how different irrigation methods affect their growth and oil production. The researchers tested drip tape and furrow irrigation with varying water levels. They found that using drip tape at 50% of the plant's water needs resulted in the highest water use efficiency. This means that the plants used water more effectively to produce seeds. The study also showed that the number of seeds and oil content of the plants were significantly affected by the irrigation methods used. Overall, using drip tape at 50% of the plant's water needs is a good way to grow black cumin in areas with limited water.