Extratos vegetais e ácido salicílico induzem resistência à podridão mole em pós-colheita de morango

Abstract

Strawberry is a widely accepted infructescence. However, the fruits are susceptible to post-harvest losses, together with the aggressiveness of fungi of the genus Rhizopus increasing the number of agrochemical applications, disappointing the current consumer market. Aqueous extracts may represent a form of alternative control, by acting as elicitor molecule, inducing defense mechanisms. Therefore, this study aimed to evaluate the effect of ginger and oregano aqueous extracts, in different 4concentrations, and salicylic acid in vitro and in vivo, through the mycelial growth and inhibition of Rhizopus stolonifer. In addition, induced resistance responses throught of quantification of total and reducing sugars, protein, disease incidence, weight reduction and evaluation of enzymatic activity (FAL, POD, SOD, chitinase and β-1,3-glucanase). The tratments 10 and 20% ginger aqueous extract were efficient in inhibiting the mycelial growth of R. stolonifer. The 20% ginger aqueous extract presented lower loss weight and higher total sugar concentration. Salicylic acid was the treatment which there was greater expression of the enzymes chitinase, SOD and FAL. These results indicate the contribution of the use of extracts and salicylic acid in the induction of resistance, but also demonstrate that further studies are needed to elucidate their effects on post-harvest fruits.