Response of susceptible carnation cultivars during thiamine application as inducer of resistance to vascular wilting caused by Fusarium oxysporum f. sp. dianthi

Abstract

Colombia is one of the main producers of carnations worldwide. However, its production has been affected by vascular wilting caused by the pathogen Fusarium oxysporum f. sp. dianthi (Fod). In previous studies, thiamine has been proposed as a potential resistance inducer for this disease, under greenhouse growth conditions. However, the specific conditions for its application must be studied when applying it under commercial conditions. In this sense, this study aimed to evaluate the effect of the thiamine foliar spray in different concentrations among some susceptible carnation cultivars in response to Fod-inoculation. For this, two in-vivo trials were carried out, using foliar spraying of thiamine as a treatment before inoculation with the pathogen Fod, then measurements of incidence, severity, and the content of phenolic and flavonoid compounds were made. It was found that thiamine application, in the concentrations evaluated, shows a statistically similar decrease in the disease incidence and severity. These results were verified using multivariate statistical analysis. In addition, it was found that the application of thiamine 1 mmol L-1 presents a positive response in reducing the effects of the disease in three susceptible cultivars. The results suggest that thiamine has the potential to be applied as a technique in the integrated management of disease in the productive sector.