Abstract Mycorrhizae are symbiotic associations between fungi and plants and are primarily responsible for nutrient transfer and survival of both partners. The present study was conducted to explore the diversity of mycorrhizal fungi in the rhizospheric soil of perennial grass species (Saccharum spontaneum, Saccharum bengalense, Setaria verticillata, Cymbopogon jwarancusa, and Typha angustata) around the district Layyah. In the subsequent experiment, the rhizospheric soils were used as inoculants, and their impact on mycorrhizal colonization in the plant and soil, and growth and physiological attributes, of Cenchrus ciliaris were investigated. The maximum hyphal, vesicles, arbuscules, dark septate endophytic and ectomycorrhizal colonization, and spore percentage were observed in the case of R-S5, i.e., rhizospheric soil, collected from Saccharum bengalense. However, the maximum (0.9310) Simpson’s index of diversity was observed in the case of R-S4, i.e., rhizospheric soil collected from Setaria verticillata. Different mycorrhizal fungal morphotypes scattered over three genera, i.e., Acaulospora, Glomus, and Scutellospora, were recorded both from rhizosphere and trap cultures. The application of spores from rhizospheric soil collected from S. bengalense (R-S5) caused the maximum increase in plant height (19.5%), number of leaves plant−1 (17.6%), leaf area (108.0%), and chlorophyll contents (29.4%) of Cenchrus ciliaris, compared to other treatments. In conclusion, the inoculation of mycorrhizal fungi significantly improves the mycorrhizal characteristics of Cenchrus ciliaris and its rhizospheric soil and ultimately enhances the growth and physiological parameters of Cenchrus ciliaris.