Evaluating Susceptibility to Commercial Fungicide of Endophytic Fungi Isolated from Roses (Rosa hybrida)

Fungal endophytes have shown their potential as biocontrol agents; however, their application in commercial fields remains limited. Continuously applying fungicides to crops (specifically to roses) may have harmful effects on endophyte growth. Endophytic fungi were isolated from R. hybrida and their susceptibility to fungicides regularly used for controlling important pathogens was analysed. This was performed in vitro, mixing several fungicide concentrations with standard medium for fungal endophytes; growth inhibition was then measured. The susceptibility of Botrytis cinerea (3015 strain), one of the most important pathogens affecting roses in Colombia, was also assessed using the same protocols. Active ingredients, such as boscalid, captan, iprodione and pyrimethanyl, showed susceptibility ranging from not sensitive (³73.75%) to regularly sensitive (³48.75% - <61.25%) for 45.45% of the fungal endophytes assessed. Endophytic fungi were highly susceptible to fungicides such as pyrimethanyl, carboxin plus thiram, fludioxonyl plus ciprodinyl and prochloraz. B. cinerea (3015 strain) presented high susceptibility (