AMF species do matter: Rhizophagus irregularis and Funneliformis mosseae affect healthy and PVY-infected Solanum tuberosum L. in a different way

Abstract

Arbuscular mycorrhizal fungi (AMF) were documented to positively influence plant growth and yield, which is extremely important for the production of many crops including potato. However, the nature of the interaction between arbuscular mycorrhiza and plant virus that share the same host is not well characterized. In this study, we examined the effect of different AMF, Rhizophagus irregularis and Funneliformis mosseae, on healthy and potato virus Y (PVY)-infected Solanum tuberosum L. The analyses conducted included the measurement of potato growth parameters, oxidative stress indicators, and photosynthetic capacity. Additionally, we evaluated both the development of AMF in plant roots and the virus level in mycorrhizal plants. We found that two AMF species colonized plant roots to varying degrees (ca. 38% for R. irregularis vs. 20% for F. mosseae). Rhizophagus irregularis had a more positive effect on potato growth parameters, causing a significant increase in the total fresh and dry weight of tubers, along with virus-challenged plants. Furthermore, this species lowered hydrogen peroxide levels in PVY-infected leaves and positively modulated the levels of nonenzymatic antioxidants, i.e., ascorbate and glutathione in leaves and roots. Finally, both fungal species contributed to reduced lipid peroxidation and alleviation of virus-induced oxidative damage in plant organs. We also confirmed an indirect interaction between AMF and PVY inhabiting the same host. The two AMF species seemed to have different abilities to colonize the roots of virus-infected hosts, as R. irregularis showed a stronger drop in mycorrhizal development in the presence of PVY. At the same time, arbuscular mycorrhiza exerted an effect on virus multiplication, causing increased PVY accumulation in plant leaves and a decreased concentration of virus in roots. In conclusion, the effect of AMF-plant interactions may differ depending on the genotypes of both symbiotic partners. Additionally, indirect AMF-PVY interactions occur in host plants, diminishing the establishment of arbuscular mycorrhiza while changing the distribution of viral particles in plants.

Physiological and Enzymatic Antioxidant Responses of Solanum tuberosum Leaves to Arbuscular Mycorrhizal Fungal Inoculation under Water Stress

“…Increases in WUE have been reported in Cinnamomum migao plants [ 37 ], Terminalia arjuna plants [ 32 ], and some wheat varieties [ 36 ] with the application of AMF and water starvation. On the other hand, in potato plants infected with potato virus Y and inoculated with the AMF Funneliformis mosseae and R. irregularis , improvements in photosynthetic parameters were observed in both healthy and infected plants, although F. mosseae was shown to improve these parameters slightly more [ 38 ].…”

Arbuscular mycorrhizal fungi inhibit necrotrophic, but not biotrophic, aboveground plant pathogens: a meta‐analysis and experimental study

“…Therefore, biotrophic pathogens may be inhibited by the upregulation of SA signaling pathway genes following AMF inoculation. By contrast, AMF inoculation may facilitate biotrophic pathogens in some contexts (Ebrahimi et al ., 2020; Khoshkhatti et al ., 2020; Deja‐Sikora et al ., 2023). This can be explained by AMF inoculation effects on foliar nitrogen; higher foliar nitrogen concentrations promote infections by biotrophic pathogen (Snoeijers et al ., 2000).…”

Symbiosis—A Perspective on the Effects of Host Traits and Environmental Parameters in Arbuscular Mycorrhizal Fungal Richness, Colonization and Ecological Functions

“…AMF, especially R. irregularis, positively increased the potato fresh and dry weights in healthy and virus-infected plants [80] Soybean AMF…”