The potential role of durum wheat-chickpea intercropping in promoting plant growth and yield in low soil phosphorus availability under field conditions

Intercropping is an agroecological practice used to enhance crop yield under environmental constraints, including phosphorus (P) deficiency. Hence, the present study aims at investigating whether durum wheat-chickpea intercropping can enhance plant growth and yield under low P availability. Karim durum wheat (Triticum durum L.) variety and two chickpea (Cicer arietinum L.) varieties [Bochra (BO) and Moubarak (MO)] were grown in field over three growing seasons in different strip: monoculture and intercropping patterns with (45 kg P2O5 ha-1) or without P fertilizer inputs. Results indicated that low P availability significantly (p < 0.001) reduced shoot dry weight (SDW) and root dry weight (RDW), total chlorophyll (Chl) and carotenoids (Car) contents, leaf area index (LAI), maximum quantum yield of photosystem II (Fv/Fm), and yield of both species. However, intercropped chickpea varieties, particularly the BO variety, significantly (p < 0.001) increased SDW by 17%, 19%, and 16% and LAI by 22%, 21%, and 26% in low P soil during the 3-year experiment, respectively. Intercropping system wheat-BO increased more grain number (GN) per spike in comparison with wheat-MO. Meanwhile, the GN was decreased in both chickpea varieties. For grain weight (GW), the intercropping system had beneficial effects on wheat GW under stress, particularly when intercropped with the BO variety. In fact, GW was improved by 21%, 16%, and 20% under low P availability during the 3 years of experiment, respectively. Moreover, higher land equivalent ratios (LER > 1) were observed in intercropping system compared with sole cropping. Likewise, intercropped chickpea also improved plant nutrient contents, Chl and Car contents and Fv/Fm ratio in wheat plants. The comparison among the two chickpea varieties revealed that BO was more efficient in improving growth and yield of wheat than MO one. Our findings suggest that intercropping durum wheat-chickpea could be an ecological practice to enhance durum wheat productivity under low P availability. [GRAPHICS] .