Medicinal plants play an important role in human health in the world. Many people in the developing and developed countries tend to take these drugs. Sustainable production of medicinal plants is very important, and intercropping is one of the components of sustainable production of these plants. Intercropping is broadly defined as the agronomic practice in which two or more crops are grown simultaneously in the same area of land [1]. Using intercropping systems increases yield, resource use efficiency, land equivalent ratio (LER), biodiversity and sustainability. Agricultural productivity was also increased by providing the resources that limit crop yield through irrigation and fertilization, and applying standardized chemical management strategies to protect crops from weeds, pests and diseases [2]. Thus, we assessed yield advantage and land use efficiency in flaxseed/soybean intercrops in the Hamedan region (Iran). Experiment was carried out in a randomized complete block design with three replications and four treatments. The treatments were included sole cropping of flaxseed and soybean, additive intercropping of 20% soybean with flaxseed and replacement intercropping of 3 rows of sesame: 4 rows of soybean (60% flaxseed:40%soybean). Results indicated that the grain yields of flaxseed and soybean were significantly affected by the planting patterns. Maximum grain yield of flaxseed was obtained at the treatment of additive intercropping of 20% soybean with flaxseed. LER index was >1 in intercropping treatments. The highest value for LER (1.89) was revealed at 20:100 (soybean/flaxseed intercrop). This concerns the optimum use of nutrients by crops from different depths of the soil due to the different root structure and the N2 fixing by soybeans in the soil that is gradually released to the flaxseed.
