Evaluation of the Effect of Intercropping with Faba Bean on Wheat Performance Under Combined Stress of Water Deficit and P Limitation in the Greenhouse

In recent years, Morocco has grappled with a precipitation shortage, exacerbating the challenge of low assimilable phosphorus (P) availability in many Moroccan soils. This presents a dual stressor for crops, hindering plant growth, particularly for staple foods like legumes and cereals, crucial to the Moroccan diet. Our study aims to assess the physiological and biochemical responses of Triticum turgidum and Vicia faba intercrops to water and P limitation, and their combined effects within a greenhouse environment. Additionally, we seek to enhance wheat growth under these challenging conditions by implementing an intercropping system. For that purpose, a variety of (Vicia faba) (Aguadulce), and (Triticum turgidum durum) (Karim) were grown in a greenhouse under sole cropping and intercropping system. The combined stress of water and P limitation was maintained by irrigating at 40% of field capacity (FC) and using an agriculture soil deficient in assimilable P (11 mg kg^-1), while control conditions were ensured by irrigating at 80% of (FC) and adding 100 mg kg^-1 of P₂O₅ of soil. At the flowering stage. Based on the agro-physiological and biochemical parameters of both species, our findings revealed significant impacts of the combined stress on the biomass of both faba beans and wheat, regardless of the cropping system. With the most notable reduction of 76%, 67 %, and 75% in intercropped faba bean shoot dry weight (SDW), root dry weight (RDW), and nodules dry weight (NDW) respectively. While intercropping showed advantages for wheat with an increase of 94% and 130% for (SDW) and (RDW) respectively under control conditions compared to sole crops, intercropping with faba bean led to reduced levels of K⁺ and Na⁺ and glycine-betaine content in wheat plants, while enhancing nitrate reductase activity under the combined stress. Comparing the two cropping systems, our comprehensive analysis suggests that combined stress adversely affected nearly all parameters studied in both species, with intercropping favoring wheat growth at the expense of faba bean plants.