Characterization of growth and conidia production of Exserohilum monoceras on different substrates.
Of the agar media tested, max. conidia production by E. monoceras occurred on V-8 juice agar (VA) or centrifuged V-8 juice agar, whereas the opt. radial mycelial growth occurred on Czapek Dox agar. The opt. temp. for radial mycelial growth and conidia production were 28 and 27°C, respectively. Light prohibited E. monoceras conidia production. The best sporulation occurred under continuous dark conditions. Echinochloa leaf decoction significantly increased conidia production on PDA and VA, and significantly increased germ tube length on PDA, lima bean agar and VA, but did not affect conidia germination. No conidia were produced in liquid media. Of 22 agricultural-based products evaluated as solid substrates, the most abundant sporulation (1.81×106 conidia/g DW) occurred on maize leaves. Conidial production by E. monoceras on maize leaves was affected by incubation period, moisture content and substrate quantity. There were no differences in germination rate, germ tube length and virulence of conidia produced on agar media or maize leaves.