Zeitschrift für Bioverarbeitung und Biotechnik

Role of Fusaric Acid Mycotoxin in Pathogensis Process of Tomato Wilt Disease Caused by Fusarium oxysporum

Abstract

Mohamed E Selim* and Nehad A El-Gammal

Different Fusarium oxysporum isolates were tested under greenhouse conditions to determine their virulence potential toward tomato plants. Severity and development of Fusarium wilt disease was recorded 4, 6 and 8 weeks after pathogen inoculation. Chromatogram assay was conducted using HPLC to evaluate the capability of the tested isolates to produce Fusaric acid and to investigate the possible correlation between FA accumulation and Fusarium wilt disease development on tomato plants. The results showed that all tested isolates were pathogenic and varied significantly with regard to their virulence potential on tomato under the test conditions. The results showed also that all tested isolates were able to produce FA. Moreover, remarkable variation in FA accumulation was observed among the tested isolates at 4, 6 and 8 weeks post inoculation with the individual isolates. Four weeks post inoculation; the recorded data indicated that no clear correlation could be detected between FA accumulation and virulence of the tested isolates. In contrary, FA accumulation was in positive proportional relationship with virulence of the tested Fusarium isolates at 6 weeks post inoculation. Furthermore, differences in production of total secondary metabolites were observed within Fusarium isolates under in vitro conditions. These results revealed that FA could be play an important role in the development of Fusarium wilt disease at middle and last stages of tomato growth, while, it seems that no distinctive role of FA in the first stages of pathogenesis process of the tested Fusarium oxysporum isolates.