Cold tolerance and preconditioning of infective juveniles of Steinernema kushidai (Nematoda: Steinernematidae)

Abstract

Steinernema kushidai infective juveniles (IJs), that had been placed onto soil and stored at 5°C after recovery from artificial culture, did not survive well, with over 90% dying within 10 days. When the IJs were preconditioned at 10°C for over 8 days, a survival rate of over 50% was seen 100 days after storage at 5°C. This preconditioning at 10°C could also be carried out on IJs suspended in distilled water. Trehalose concentration in the IJs increased from almost undetectable levels to 1.4% of the dry weight when S. kushidai IJs in distilled water were preconditioned at 10°C for 20 days.