PERICARP PHENYLPROPANOIDS: RESISTANCE FACTORSTO MAIZE EAR ROT CAUSED BY Fusarium verticillioides

SAMPIETRO, D.A.; FAUGUEL, C.; BELIZAN, M.M.E.; VATTUONE, M.A.; PRESELLO, D.A.; CATALAN, C.A.N.

SAN MIGUEL DE TUCUMAN

Congreso; XXIX ANNUAL SCIENTIFIC MEETING OF TUCUMAN BIOLOGY ASSOCIATION; 2012

TUCUMAN BIOLOGY ASSOCIATION

Fusarium verticillioides, the ethiological agent of maize ear rot, contaminates grains with fumonisins that are potentially toxic for humans and animals. The development of more resistant hybrids is the less expensive and more sustainable strategy to minimize fumonisin contamination. The aims of this work were: 1) to determine content of pericarp phenylpropanoids in 11 maize genotypes from INTA germplasm; 2) to evaluate if pericarp phenylpropanoids play a role in resistance against F. verticillioides. Eleven maize genotypes were grown in Pergamino for two years and inoculated with microconidial suspensions of P364 (a high fumonisin producer strain). Disease severity, fumonisin contamination and content of phenylpropanoids were evaluated in the grains during harvest .The pericarp of the maize genotypes contained trans-ferulic, cis-ferulic and p-coumaric (pCA) acids and fi ve diferulates (DFAs). The most abundant DFAs were 8,5´-DFA benzofuram, followed by 8,5´-DFA and 8,8´-DFA. Field resistant genotypes exhibited the highest contents of phenylpropanoids, which were associated with the lowest fumonisin accumulation (-0.61 > r >-0.90). High levels of pericarp phenylpropanoids proved to be a maize trait associated with lower disease severity and fumonisin accumulation.