Methods for long-trem storage of Predatory mite Neoseiulus californicus (McGregor) (Acari: Phytoseiidae)

Neoseiulus californicus (McGregor) (Acari: Phytoseiidae) is one of the most effective predators in controlling various pest species in greenhouses. Cold storage is a common method for preserving natural enemies in insectariums long-term. This study used different food materials (wheat bran, pumice, hollow oat, corn pollen sheath, date pollen sheath, sawdust, and rubber) to store N. californicus to examine its survival and predation. In each container, 20 female mated predatory mites (3-4 days old) were placed and kept for 1, 5, 10, and 15 days at four different temperatures (0, 5, 10, and 15°C with 60% relative humidity). The percentage of survival and lifespan were determined and the efficiency of the stored predatory mites (fecundity rate and predatory rate) was also compared with the main colony individuals (as a control treatment). The survival rate in the materials, including corn and date pollen sheaths, was higher than the other materials. The survival rate of individuals 1, 10, 15, and 20 days after storing predatory mites in corn pollen sheaths was 81, 70.62, 54.87, and 37.75%, respectively. Five or 10 °C was the best temperature for storing predatory mites. The efficiency of the predatory mite kept with corn pollen sheaths at 5°C was not significantly different from the control. Therefore, storing and transporting N. californicus to the market with corn and date pollen sheaths for a maximum period of 10 days at 5 °C is recommended.