Yield, yield components, and essential oil content of dragon's head (Lallemantia iberica) intercropped with chickpea (Cicer arietinum l.)

Intercropping improves the efficiency of using resources such as water, nutrients, and solar radiation, which consequently increases yield per unit area. Moreover, it enhances soil fertility and plant nutrient supply. This study was conducted to evaluate the grain yield and production of dragon head essential oil under intercropping with chickpeas. The experiment was arranged in a randomized complete block design with three replications. Intercropping patterns included the pure stand of dragon's head, monoculture of two chickpea varieties (Azad, Arman), additive intercropping of the optimal density of Azad and Arman chickpea + 40%, 60%, and 80% of the optimum density of dragon's head. The highest and lowest biomass and grain yield of the dragon's head were obtained in sole cropping and 80% dragon's head + 100% Azad chickpea, respectively. Moreover, the highest essential oil content and yield of the dragon's head were obtained from the cropping pattern of 60% dragon's head + 100% Azad chickpea. Also, the land equivalent ratio (LER) was greater than one for all intercropping patterns, except for the intercropping of 80% dragon's head along with 100% Arman and Azad chickpeas, and the highest partial LER of dragon's head was obtained from intercropping of 40% dragon's head with100% Arman chickpea. In general, intercropping 40% dragon's head with100% density of both cultivars of the chickpea seems a suitable model for intercropping these two crops.