Morphological and molecular identification of indigenous arbuscular mycorrhizal fungi in the rhizosphere of chickpea (Cicer arietinum) and their role in nutrient uptake

Abstract

: This study aimed to evaluate the effect of arbuscular mycorrhizal fungi (AMF) on the growth, nutrient uptake, and productivity of chickpea (Cicer arietinum). We investigated the diversity of indigenous AMF in their natural habitat and their effect on the plant and elemental characteristics of chickpea by analysing soil physicochemical properties, root colonisation, AMF spore diversity, and elemental composition of chickpea rhizosphere in two locations (Bhakkar and Khushab, Pakistan). Nitrogen levels of 5.47 g/kg and 4.51 g/kg were found in the rhizosphere soils of Bhakkar and Khushab, respectively. Root colonisation was higher (48.5%) in Khushab (Bhakkar, 35.5%), influencing phosphorus absorption in both regions. Molecular analysis identified 21 AMF taxa, with Glomus and Acaulospora being the most dominant genera. Variations in spore sizes were found, with Glomus measuring 10–191 μm, Acaulospora 125–152 μm, Sclerocystis 110–174 μm, and Gigaspora 65–184 μm. Plant analysis revealed that plant materials from Bhakkar had 1.72% ash, 1.16% fat, 3.78% fibre, and 13.05% protein; samples from Khushab had 1.90% ash, 1.25% fat, 3.24% fibre, and 11.5% protein. Elemental concentrations of chickpea plants from Bhakkar were N = 2.68%, P = 32.98 mg/kg, and K = 33.32 mg/kg, whereas those from Khushab were N = 1.94%, P = 1.17 mg/kg, and K = 43.06 mg/kg. Molecular analysis revealed AMF species with a range of 250–1100 bp. Root colonisation was inversely related to soil phosphorus levels but had a positive effect on plant moisture, fats, and carbohydrates. Morphological and molecular identification showed a relatively high AMF taxa in the rhizosphere of chickpea in both regions. Despite their benefits, the potential of AMF as biofertilisers has not been fully utilised due to prevailing agronomic practices.