Relación entre el contenido de compuestos fenólicos del grano de sorgo granifero y la resistencia al enmohecimiento

MARTINEZ, M.J.; GIORDA, L.; BALZARINI, M.; ZYGADLO, J.

Pergamino-Buenos Aires

Simposio; III Simposio Nacional de Sorgo. I Conferencia Internacional de Sorgo. Del Presente al Futuro.; 2016

Sorghum is a wide adapted specie that is used for human food, animal feed and industry. It is almost unique among cereals to produce abundant phenolic compounds in pericarp and seed coat of the grain. These polyphenols include condensed tannins, which are also called proanthocyanidins or procyanidins, consisting of polymerized flavan-3-ol units, found in sorghum with a pigmented testa layer; these ones are associated in reducing protein digestibility, although recent researches have found potential health benefits and nutraceutical effects. Tannins sorghums are generally resistant to bird damage, postharvest weathering and molding caused by Fusarium verticillioides. The aim of this study was to determine the effect of grain molding caused by this fungi on the phenolic compounds content in susceptible and resistant cultivars. Resistant and susceptible sorghum cultivars were planted at Manfredi Experimental Station INTA, Córdoba-Argentina, in a split plot design with four replicates. The main plots were the treatments: uninoculated (fungicide protected) and inoculated with F. verticillioides (1x106 conidias/ml). The subplots were 9 cultivars. The inoculations were performed on the panicles since they reached 50 % of anthesis. Results indicate that the content of flavan-3-ols; flavan-4-ols and total polyphenols were significantly greater in resistant than susceptible cultivars and within inoculation treatments. Resistant genotypes without tannins, had significant greater flavan-4-ol contents than the susceptible ones without tannins, as a response to the pathogen presence, suggesting a resistant mechanism.