Metabolic and antioxidant effects of inoculation with arbuscular mycorrhizal fungi in crops of flesh‐coloured Solanum tuberosum treated with fungicides

Abstract

BACKGROUND: Solanum tuberosum tubers have higher content of phenolic compounds such as hydroxycinnamic acid derivatives (HCAD) and anthocyanins in coloured genotypes. The use of fungicides for crops is common, but there are few studies regarding the interaction of fungicides and arbuscular mycorrhizal fungi (AMF). Here, the AMF-plant interactions and the metabolic responses of three potato genotypes with different tuber colorations (VR808, CB2011-509 and CB2011-104) inoculated with Claroideoglomus claroideum (CC), Claroideoglomus lamellosum (HMC26) or Funneliformis mosseae (HMC7) were studied together with the use of the fungicides MONCUT (M) and ReflectXtra (R). Mycorrhizal traits, phenolic compound profiles and antioxidant activity (AA) were evaluated.RESULTS: Despite only two HCADs being identified, with 5-caffeolquinic acid the most abundant, four anthocyanins were detected only in purple potato genotypes. The anthocyanin and HCAD profiles, as well as AA, showed that the CB2011-104 genotype had better characteristics than the other genotypes, while VR808 and CB509 showed similar responses. The responses were dependent on the specific combinations of genotype, fungicide and the AMF strain, and generally showed better responses when colonized by AMFs.CONCLUSION: The three potato genotypes had differential responses depending on the inoculated AMFs and the fungicide applied before sowing, where the optimal combinations for antioxidant response, mycorrhization degree and performance were HMC26/R for VR808, HMC7/M for CB2011-509 and HMC26/M for CB2011-104. Our results suggest the existence of functional compatibility that can be registered as beneficial effects even at the genotypic level of the host regarding a specific AMF strain.

Effect of Inoculation with Arbuscular Mycorrhizal Fungi and Fungicide Application on the Secondary Metabolism of Solanum tuberosum Leaves

“…Arbuscular mycorrhizal symbiosis activates the defense mechanism in host plants, increasing the antioxidant activity of phenolic compounds and improving plant growth [ 23 , 24 ]. Fungicide application may influence AM symbiosis, although the results are quite varied depending on the active ingredient, dose, timing of application, mode of application, and environmental conditions [ 19 , 20 ]. Additionally, it is well documented that plant genotype can influence AM symbiosis [ 19 , 21 ], similar to the use of commercial fungicides as MONCUT or ReflectXtra [ 22 ].…”

“…Fungicide application may influence AM symbiosis, although the results are quite varied depending on the active ingredient, dose, timing of application, mode of application, and environmental conditions [ 19 , 20 ]. Additionally, it is well documented that plant genotype can influence AM symbiosis [ 19 , 21 ], similar to the use of commercial fungicides as MONCUT or ReflectXtra [ 22 ]. According to Hage-Ahmed et al, (2019) [ 21 ], some AMF species are more resistant to certain fungicides, whereas others appear to have a neutral effect on AM colonization, and others seem to influence AM symbiosis in a positive manner.…”

“…The fungicide ReflectXtra showed a positive effect on the leaves of Solanum tuberosum plants inoculated with AMF in most of the treatments. However, it would be interesting to evaluate other fungicides with similar characteristics on this plant and to analyze other mechanisms that could benefit from inoculation with AMF under the effect of fungicides in plants and also in tubers [ 19 ].…”

“…In contrast, Rhizoctonia spp. are another major fungal pathogen of potatoes, causing economic losses due to stem cankers and black scurf disease [ 19 ], MONCUT 40 SC is a systemic fungicide with preventive and curative action that efficiently controls Rhizoctonia spp., preventing their growth and penetration into the root and tuber structures, which causes collapse of the hyphae and stops their growth. Multiple fungicides can be used for this condition.…”

Physiological and Metabolic Effects of the Inoculation of Arbuscular Mycorrhizal Fungi in Solanum tuberosum Crops under Water Stress

“…In previous studies, the presence of quercetin derivatives and chlorogenic acids has been reported in leaves [ 24 ]. In the roots, their presence is primarily due to exudates of oxalic acid, while in tubers, the contents of these compounds depend on the plant variety, highlighting the presence of chlorogenic acids, such as 5-caffeoylquinic acid, and anthocyanins, such as those derived from petunidins, [ 25 ]. Under drought stress, the total phenol content in Solanum lycopersicum plants increases between 50% and 83% compared to the control [ 26 ].…”