Storage temperature influences desiccation and ultra violet radiation tolerance of entomopathogenic nematodes

1. The effect of cold (5 °C) and warm (35 °C) storage on desiccation tolerance of cold-adapted Steinernema feltiae, intermediate S. carpocapsae and warm-adapted S. riobrave was evaluated at 5 and 35 °C.2. Desiccation survival of all three species at 5 °C was enhanced by both the cold and warm storage. At 35 °C, desiccation survival of S. feltiae and S. riobrave was enhanced by only warm storage and of S. carpocapsae by only cold storage.3. When desiccated at 5 °C, both warm and cold stored S. carpocapsae and S. feltiae, and the cold stored S. riobrave maintained significantly higher original virulence against Galleria mellonella larvae than cohorts stored at culture temperature. When desiccated at 35 °C, both warm and cold stored S. riobrave, and warm stored S. carpocapsae and S. feltiae maintained significantly higher original virulence than cohorts stored at culture temperature.4. After 3 h exposure to ultra violet (UV) radiation stress at 340 nm, the warm and cold stored S. carpocapsae and S. riobrave maintained significantly higher original virulence than cohorts stored at culture temperature. The virulence of UV stressed S. feltiae was unaffected by storage temperature.5. Trehalose content of both warm and cold stored S. feltiae, cold stored S. carpocapsae and warm stored S. riobrave was positively correlated with their desiccation survival at 5 and 35 °C. Trehalose content was also positively correlated with the virulence of both warm and cold stored S. carpocapsae, and warm stored S. riobrave following exposure to UV stress.