Ectomycorrhizal and non‐mycorrhizal rhizosphere fungi increase root‐derived C input to soil and modify enzyme activities: A ¹⁴C pulse labelling of Picea abies seedlings

Abstract

Consequences of interactions between ectomycorrhizal fungi (EcMF) and nonmycorrhizal rhizosphere fungi (NMRF) for plant carbon (C) allocation belowground and nutrient cycling in soil remain unknown. To address this topic, we performed a mesocosm study with Norway spruce seedlings [Picea abies (L.) H. Karst] inoculated with EcMF, NMRF, or a mixture of both (MIX). 14 CO 2 pulse labelling of spruce was applied to trace and visualize the 14 C incorporation into roots, rhizohyphosphere and hyphosphere. Activities and localization of enzymes involved in the C, nitrogen (N) and phosphorus (P) cycling were visualized using zymography. Spruce seedlings inoculated with EcMF and NMRF allocated more C to soils (EcMF: 10.7%; NMRF: 3.5% of total recovered C) compared to uninoculated control seedlings. The 14 C activity in the hyphosphere was highest for EcMF and lowest for NMRF. In the presence of both, NMRF and EcMF (MIX), the 14 C activity was 64% lower compared with EcMF inoculation alone. This suggests a suppressed C allocation via EcMF likely due to the competition between EcMF and NMRF for N and P. Furthermore, we observed 57% and 49% higher chitinase and leucine-aminopeptidase activities in the rhizohyphosphere of EcMF compared to the uninoculated control, respectively. In contrast, β-glucosidase activity (14.3 nmol cm −2 h −1 ) was highest in NMRF likely because NMRF consumed rhizodeposits efficiently. This was further supported by

Legume-based crop diversification reinforces soil health and carbon storage driven by microbial biomass and aggregates

“…1), microbial functioning and biodiversity (McDaniel et al, 2014;Mooshammer et al, 2022). This could simultaneously enhance microbial activities and production of microbial-derived binding agents (e.g., glomalin), which are imperative for promoting soil aggregation (Bossuyt et al, 2001;Zhou et al, 2020Zhou et al, , 2022a. Further yet, due to the less physical disturbance to soil aggregates during the three crop harvests over two years (Jin et al, 2021), thus soil aggregate stability was larger under diversified cropping versus wheat/maize.…”

The effect of white grub (Maladera Verticalis) larvae feeding on rhizosphere microbial characterization of aerobic rice (Oryza sativa L.) in Puer City, Yunnan Province, China

“…Here, we found that rhizosphere fungal number and Shannon index strongly correlated with soil physicochemical properties and soil enzyme activities. Rhizosphere fungal community structures were primarily shaped by the total N, available N, and available P of soil [ 78 ], which increased the activity of chitinase, leucine-aminopeptidase, acid phosphatase, and β-glucosidase [ 79 ]. However, we did not determine if the high correlation between fungal activity and soil enzyme activity is due to fungal secretion.…”

Mechanisms of Arbuscular Mycorrhizal Fungi Increasing Silicon Uptake by Rice

“…5 As obligate biotrophs, AMF rely on their host plants for carbon (C) supply. 17 Plants allocate lipids from their roots to the fungi, a process vital for sustaining colonization by both mutualistic mycorrhizal and parasitic fungi. 18 Little is known about the interplay between AMF and Si accumulation, although a growing body of evidence suggests the occurrence of a mutualistic relation between the two.…”

“…Mycorrhizal extraradical hyphae extend beyond these P-depleted zones, where they access and utilize available P that would otherwise be inaccessible to plants . As obligate biotrophs, AMF rely on their host plants for carbon (C) supply . Plants allocate lipids from their roots to the fungi, a process vital for sustaining colonization by both mutualistic mycorrhizal and parasitic fungi .…”