Spermidin phytohormone and induce resistance of two tolerant Termeh and sensitive Capitan cultivar of tomato against Fusarium wilting disease caused by Fusarium oxysporum fsp. Lycopersici

In this research, the effects of spermidin polyamine on induce resistance of tomato to fusarium wilting disease caused by Fusarium oxysporum fsp. Lycopercisi was assayed. For this reason, a designed factorial experimental based on randomized completed block design in greenhouse condition was done. A solution of spermidin at 1 and 0.1 mM concentration was used by the spray on infected and non infected plants at 4 leaf stage. Sampling was performed at two time interval (48 and 72h) after inoculation. The level of several antioxidants enzyme and also expression of some transcription factors as related to pathogenesis (npr1, eds1 and pds genes) were measured by spectophotometery and real time PCR, respectively. The results showed that approximately, the highest enzyme activity was related to infected tomato plants treated with 1mM spermidin after 72h post inoculation with fusarium oxysporum fsp. Lycopercisi. Gene expression analysis showed that all tested genes were affected by spermidin application in infected plants. The highest and lowest expression level was observed for npr1 and pds genes, respectively. Based on these results we suggest that exogenous application of sprmidin with appropriate concentration to plant under stress condition could improve plant growth condition which can be resulted to plant resistance against pathogen attack