Alleviating Plant Water Stress with Biofertilizers: A Case Study for Dragon’s Head (Lallemantia iberica) and Chickpea (Cicer arietinum L.) in a Rainfed Intercropping System

Legume/non-legume intercropping combined with biofertilizer application is a sustainable strategy for improving nutrient uptake and crop productivity. This study investigated the effects of biofertilizers and cropping patterns on macro- and micronutrients, seed yield (SY), and physiological characteristics of chickpea (Cicer arietinum L.) and Dragon’s head (Lallemantia iberica). The treatments included five cropping patterns: Dragon’s head monocropping (D_m), chickpea monocropping (C_m), intercropping one row Dragon’s head + one row chickpea (1D:1 C), intercropping two rows Dragon’s head + one row chickpea (2D:1 C), and intercropping one row Dragon’s head + two rows chickpea (1D:2 C), and two biofertilizer applications: arbuscular mycorrhizal fungi (AMF) and bacterial biofertilizer (BF). The D_m and C_m treatments with BF produced the maximum SY for chickpea (977.9 kg ha^–1) and Dragon’s head (993.6 kg ha^–1). In contrast, the intercropping ratios of 1D:1 C and 2D:1 C with BF produced the highest macro- and micronutrient concentrations for chickpea and Dragon’s head, respectively. Also, 1D:1 C and 2D:1 C intercropping with BF produced the highest chlorophyll a and b and carotenoid concentrations in both species. Interestingly, D_m and C_m without fertilization produced the maximum proline (1.68 and 6.01 mg g^–1) and carbohydrate (11.07 and 10.65 mg g^–1) concentrations in chickpea and Dragon’s head, respectively. These results indicate that intercropping chickpea and Dragon’s head (especially the 2D:1 C intercropping pattern) combined with BF application may pave the way to more sustainable agronomy for improving physiological activities and nutrient uptake.