Strip Intercropping With Chickpea Supports Production of a Valuable Medicinal Oilseed

Abstract

Intercropping is prevalent in arid and semi-arid regions due to its high and stable productivity and efficient resource utilization. In this study, we evaluated the improving radiation use efficiency (RUE) and economic advantage in chickpea (Cicer arietinum L) and dragon's head (Lallemantia iberica) intercropping under an irrigation regime and sowing date. Field experiments were performed using a factorial split plot based on a randomized complete block design. The experimental treatments included irrigation systems at three levels: supplementary irrigation (irrigation after sowing and pre-flowering stage) (IS); complete irrigation as control (irrigation based on 20% depletion of available soil water) (I20), and deficit irrigation (irrigation based on 40% depletion of soil water) (I40); the second factor was the autumn sowing date (S1) and spring sowing date (S2), and the third factor was monocropping of chickpea (MC), monocropping of L. iberica (Ml), and intercropping of chickpea and L. iberica (In). The In (I20) treatment increased RUE in chickpea and L. iberica by 1.42 and 1.25 g/MJ, respectively, by extending the growth period. Intercropping proved more profitable than monocropping, with reduced irrigation needs and minimized drought stress during autumn and spring sowings. Chickpea exhibited a higher competitive ratio than L. iberica, indicating their dominance in the intercropping system, which was supported by the land equivalent ratio (LER) results. Adapting crop systems to local agroecological conditions is vital for enhancing resource efficiency and achieving sustainable agricultural outcomes. Based on this, intercropping these species shows promise in mitigating the negative impact of water and light limitations on crop yield.