Factors influencing survival of phialospores of Chalara elegans in organic soil

The influence of soil moisture, temperature, crop plant, flooding, and addition of plant residues and CaCO 3 on survival of phialospores of Chalara elegans in organic soil was studied. The extent of survival of phialospores (number of propagules recovered from artificially infested soil) was monitored over a 19-wk duration using a semiselective medium (TB-2RBA). Survival was significantly greater (P≤0.01) in soil maintained at a constant soil moisture level (matric potential of about -50 J/kg) than when moisture level gradually declined to about -900 J/kg; propagules could be recovered from both soil moisture treatments for up to 19 wk