Acetaldehyde suppresses growth, changes conidia morphology and reduces the production of adenosine 3',5'-cyclic monophosphate in a dose dependent manner in Alternaria alternata.

One-day-old cultures of the plant pathogenic fungus Alternaria alternata were exposed to 0%, 5% and 10% acetaldehyde mixed with distilled water. Fungal growth data showed that, overall, the 5% and the 10% acetaldehyde treatments significantly inhibited the growth of A. alternata, and that acetyldehyde also facilitated maturity and multicellularity of fungal conidia. The increase of the acetyldehyde dose also caused correlated decrease of adenosine 3',5'-cyclic monophosphate produced by A. alternata.