The arbuscular mycorrhizal symbiosis attenuates symptom severity and reduces virus concentration in tomato infected by Tomato yellow leaf curl Sardinia virus (TYLCSV)

Abstract

The arbuscular mycorrhizal (AM) symbiosis is considered a natural instrument to improve plant health and productivity since mycorrhizal plants often show higher tolerance to abiotic and biotic stresses. However, the impact of the AM symbiosis on infection by viral pathogens is still largely uncertain and little explored. In the present study, tomato plants were grown under controlled conditions and inoculated with the AM fungus Funneliformis mosseae. Once the mycorrhizal colonization had developed, plants were inoculated with the Tomato yellow leaf curl Sardinia virus (TYLCSV), a geminivirus causing one of the most serious viral diseases of tomatoes in Mediterranean areas. Biological conditions consisted of control plants (C), TYLCSV-infected plants (V), mycorrhizal plants (M), and TYLCSV-infected mycorrhizal plants (MV). At the time of analysis, the level of mycorrhiza development and the expression profiles of mycorrhiza-responsive selected genes were not significantly modified by virus infection, thus indicating that the AM symbiosis was unaffected by the presence and spread of the virus. Viral symptoms were milder, and both shoot and root concentrations of viral DNA were lower in MV plants than in V plants. Overall F. mosseae colonization appears to exert a beneficial effect on tomato plants in attenuating the disease caused by TYLCSV.

Arbuscular Mycorrhiza Changes the Impact of Potato Virus Y on Growth and Stress Tolerance of Solanum tuberosum L. in vitro

“…This discrepancy may be related to the various characteristics of potato cultivars used in both experiments (tolerant vs. sensitive), since virus behavior may differ depending on the host genotype (Valkonen, 2015;Davie et al, 2017). Nevertheless, the investigation by Maffei et al (2014), examining different experimental biosystem consisting of tomato, Tomato yellow leaf curl Sardinia virus (TYLCSV) and Funneliformis mosseae, indicated attenuation of viral disease symptoms upon symbiosis. More recently, Wang et al (2018) showed that mycorrhization of tomato affected by Cladosporium fulvum (pathogenic mold) caused significant increase in activities of both superoxide dismutase and peroxidase, which correlated with decrease in H 2 O 2 level.…”

Enhanced tomato disease resistance primed by arbuscular mycorrhizal fungus

“…Mycorrhizal associations benefit not only plant nutrient absorption ( Smith and Read, 2008 ), but also plant resistance to diverse abiotic stresses ( Ruiz-Lozano et al, 1996 ) and soil-borne fungal pathogens ( Harrier and Watson, 2004 ; Bi et al, 2007 ). More interestingly, AM symbiosis also enhances plant resistance against foliar pathogens such as fungal pathogens [e.g., Botrytis cinerea ( Pozo et al, 2010 ; Fiorilli et al, 2011 ) and A. solani ( Fritz et al, 2006 )], bacteria [e.g., Xamantomonas campestris ( Liu et al, 2007 ) and viruses (e.g., Tomato yellow leaf curl Sardinia virus ( Maffei et al, 2014 )].…”

Mycorrhiza-induced alleviation of plant disease caused by Clavibacter michiganensis subsp. michiganensis and role of ethylene in mycorrhiza-induced resistance in tomato

“…(MUCL 43204), Claroideoglomus claroideum (BEG 23) and Funelliformis mosseae (BEG 12) had an intermediate level of colonization, confirming that tomato is intermediate in mycorrhizal dependency [28]. It is known that AM symbiosis could enhance plant resistance against a wide range of viral, bacterial and fungal pathogens [10,12,21,23,38], but our report is the only one regarding the bacterial disease caused by Cmm. The present study showed that Ri induced the most effective systemic resistance against Cmm among seven AMF isolates tested.…”