Testing effects of natural resin and synthetic terpenes on conidial germination and growth of entomopathogenic fungi

Abstract: The effects of natural resin and synthetic terpenes on conidial germination and growth of selected entomopathogenic fungi was tested under laboratory conditions.Liquid resin, solidified “scrape” resin and colophony inhibited conidia germination and fungal growth of B. bassiana. All three substances inhibited conidia germination of M. anisopliae and liquid resin inhibited fungal growth of M. anisopliae, but only colophony inhibited conidia germination of I. fumosorosea, no inhibition of fungal growth were found with the latter species.All synthetic substances (-)-α Pinene, (-)-β Pinene, Myrcene and R-Limonene inhibited germination of conidia up to 48 hours at least within the area of 10 mm next to the test substance. However, no inhibition of fungal growth was found with (-)-α Pinene and (-)-β Pinene, Myrcene caused a very small inhibition zone (1-2 mm) in B. bassiana and M. anisopliae, but only for a period of one week, R-Limonene caused a very small inhibition zone (1-2 mm) only in B. bassiana for one week; after that time no inhibition was found in fungal growth with any of the terpenes.