The influence of flavonoids in maize pericarp on fusarium ear rot symptoms and fumonisin accumulation under field conditions

Abstract

Breeding efforts have been undertaken to increase resistance of maize to fusarium ear rot (FER) and to fumonisin accumulation. Flavonoids in the pericarp of the kernels are considered particularly able to reduce the fumonisin accumulation. The aim of this 2-year field study was to assess the effect of flavonoids on FER symptoms and fumonisin contamination in maize kernels using two isogenic hybrids, one providing pigmentation in the pericarp (P1-rr) and the other without it (P1-wr). FER incidence (FERi), FER severity (FERs), the incidence of infections caused by Fusarium spp. in symptomless kernels (FF) and fumonisin contamination (FUM) were assessed in both hybrids. Significant differences between the two hybrids were detected mainly in 2012 trials where P1-rr showed lower FERi (P < 0Á01), FF (P < 0Á05) and FUM (P < 0Á1) than P1-wr. Site, characterized by local temperature and precipitation, played a relevant role in modelling all the measured variables, as its effect was highly significant in both years, whether they were considered individually or altogether. The interaction of hybrid with location was a significant (P < 0Á001) source of variation only for FF. FF, together with FERi, was also significantly (P < 0Á001) influenced by the interaction of hybrid with year. In general, FUM was more influenced by year and location parameters, such as temperatures during late ripening, than by flavonoid presence in kernel pericarp. The results indicate that flavonoid pigments alone may not be an important component in the resistance of maize to fumonisin accumulation.

Metabolomics to Decipher the Chemical Defense of Cereals against Fusarium graminearum and Deoxynivalenol Accumulation

“…In addition, flavonoids are thought to participate to the reinforcement of plant structures and act as a physical barrier against fungal infection [ 52 ]. This role was recently supported by the findings of Venturini et al [ 53 ] that strongly suggest the involvement of flavonoids in resistance to F. verticillioides through their contribution to kernels’ hardening. Flavonoids can also protect plant cell wall integrity upon fungal infection by inhibiting the activity of several plant cell wall degrading enzymes secreted by fungal pathogens to penetrate plant tissues [ 54 ].…”

Genome‐Wide Association Study of Resistance to Ear Rot byFusarium verticillioidesin a Tropical Field Maize and Popcorn Core Collection

“…This is a class of enzymes that catalyze, among other things, the conversion of flavonol to flavonol 3-O-glucosyltransferase (Martin et al, 2001) and is thus important in the production of flavonoids. Flavonoids are reported to reduce Fusarium infection in numerous investigations (Treutter, 2005(Treutter, , 2006Mierziak et al, 2014;Venturini et al, 2015) and have the ability to inhibit spore development and restrain mycelium hyphae elongation of plant fungal pathogens (Treutter, 2006;Mierziak et al, 2014). This is done by hardening maize kernel pericarp, and thus flavonoids are thought to create a physical barrier against fungal infection and reduce mycelial progress from the infected to the intact flanking kernels.…”

Transcriptomic Analysis of a Susceptible African Maize Line to Fusarium verticillioides Infection

“…[ 1 , 7 ]. Fusarium verticillioides is a common fungal species isolated from maize crops [ 1 , 8 ], and can result in Fusarium ear rot (FER) disease, which reduces grain yield and grain quality [ 9 , 10 , 11 ]. More importantly, F. verticillioides infection can also lead to the production of toxic fumonisins, which are associated with cancers and birth defects in humans [ 2 , 12 ].…”