Medicinal plants play pivotal role in human health. Intercropping system is one of the most important strategies for achieving sustainable agriculture goals. The purpose of this research was evaluation of quantitative and qualitative traits of Nigella sativa L. and Trigonella foenum-greacum L. as medicinal plants, in additive series of intercropping. Field experiment was conducted in research farm of Kurdistan University during spring 2016. Treatments consisted of 100% black cumin + 12/5% fenugreek, 100% black cumin + 25% fenugreek, 100% black cumin + 37/5% fenugreek, 100% black cumin + 50% fenugreek and their monocultures. Experimental design was randomized complete block design with three replications. In this study, different traits consisted of plant height, capsules number per plant, biological yield, grain yield and essential oil content of black cumin and plant height, pod number per plant, biological yield and grain yield of fenugreek and LER were evaluated. The results showed that intercropping treatments had significant effect on traits of both plants. The highest plant height, capsules number per plant, biological yield and grain yield of black cumin were belong to 100% black cumin+ 12/5% fenugreek and the lowest values of mentioned characteristics were belong to monoculture of black cumin. The highest essential oil content was obtained from 100% black cumin+ 50% fenugreek and the highest values of fenugreek traits were belong to it ´s monoculture. Such findings were retrieved by other investigators on different medicinal plants in intercropping system [1,2]. The highest land equivalent ratio was obtained of 100% black cumin+ 12/5% fenugreek. Therefore, it can be concluded that additive series design of 100% black cumin+ 12/5% fenugreek was the best treatment in comparison whit the other treatments.
