Earthworm (Pheretima guillelmi)-mycorrhizal fungi (Funneliformis mosseae) association mediates rhizosphere responses in white clover.

Earthworms and arbuscular mycorrhizal fungi (AMF) are beneficial organisms in the soil and play an important role in improving soil fertility and plant growth. The objective of this study was to analyze the response of single versus dual inoculation of earthworms (Pheretima guillelmi) and AMF (Funneliformis mosseae) on mycorrhizal growth, root morphology, and rhizosphere properties of white clover (Trifolium repens). Addition of earthworms significantly increased the degree of root AMF colonization, while decreased hyphal length and spore number in the soil. Single or dual inoculation of F. mosseae and P. guillelmi significantly increased root traits (total length, area, volume, and average diameter), soil phosphatase activities (acid, neutral, and alkaline), easily extractable and total glomalin-related soil protein content, the percentage of soil water-stable aggregates at the size of 2–4 mm, 1–2 mm and 0.5–1 mm, aggregate stability, Bray-P, and soil organic carbon (SOC) contents. Among them, the dual inoculation further amplified the effect on glomalin production, phosphatase activity, and aggregate stability, but did not show a superposition effect on root improvement, Bray-P, and SOC. Our study, hence, suggested that AMF and earthworms have synergistic roles in elevating rhizosphere properties vis-à-vis agronomic responses of white clover. • Effects of earthworm-AMF (singly and in combination) on rhizosphere environment and crop response were studied. • Earthworms increased root AMF colonization, but reduced hyphae and spores in soils. • AMF or earthworms singly improved root traits, Bray-P, and soil organic carbon contents, but dual application of AMF and earthworms did not show a major effect than single application. • Single AMF or earthworms increased aggregation, phosphatase, GRSP, and dual addition amplified these responses. [ABSTRACT FROM AUTHOR]