Predatory Mite (Amblyseius swirskii)
Amblyseius swirskii adults have 8 legs and the body is singular rather than segmented with under 20 back hairs. A. swirskii cannot be distinguished from a number of other predatory mites such as A. cucumeris, A. californicus, or A. andersoni with the naked eye. The differences in appearance are subtle and can only be seen under microscope. The color of A. swirskii is dependent on what the mites have been eating. This can vary from dark red to purple, to light yellow. With thrips and whitefly as prey, the color tends to be a kind of light orange. The mites feed by piercing small arthropod prey or grains of pollen with their mouthparts, and draining the contents.
Amblyseius swirskii is a predatory mite native to the coastal regions of the Middle East and North Africa on fruit trees. It is an ideal product to be used in crops that are grown under protection in warm conditions, such as Cannabis, peppers, cucumbers, gerbera and eggplant. It can be used on other crops during the summer, provided that average daytime temperatures exceed 68F. It breeds extremely quickly under warm and humid environmental conditions. It predates on thrips, whiteflies and other pests. In the absence of prey it can also survive on the plant by feeding on pollen and mold. It prefers a warm and humid climate, but can survive cooler nights during the winter months in semi-protected crops by moving lower down the plants where it benefits from the warmer micro-climate closer to the ground. The mite will emerge onto the crop looking for prey.
Broad Mites, Two-Spotted Spider Mites, Thrips, Whiteflies
These mites can tolerate temperatures up to 95°F., but do best in temperatures between 60° -85° F. They do well in humidities ranging from 50%-90%. To raise the humidity level you can lightly mist the plants or surrounding walkways. The temperature is an important aspect, if the temperature falls below 60 °F the predatory mite will be virtually inactive. Their optimum temperature is between 77-83 °F.
Traditional release rates are approximately 500 predators for every 10-15 ft. of crop row. Or 5-15 per plant, depending on infestation.
Adult female mites lay single eggs onto leaf hairs. The mites go through three immature stages: larva, protonymph, and deutonymph, before becoming adults. At 77F, the entire cycle from egg to adult can take less than 7 days. All mobile stages are predatory.
Introduce Amblyseius swirskii early in the crop/pest cycle to protect against the pest build up, but only when average temperatures are above 68F.