Tip Top Bio-Control Technical Bulletin
Western flower thrips (Frankliniella occidentalis). Onion thrips (Thrips tabaci) also Cyclamen, Two Spotted, Broad and Rust mites.
Cucumeris is a species of predatory mite that feeds on immature stages of thrips. It also feeds on pollen, two spotted mites and other species of mites. Cucumeris adults are pear-shaped, tan colored mites, less than 0.5mm (1/50 inch) long.
About 60% are female. Well-fed females will lay up to 3 eggs per day for 35 days. Their eggs are round, transparent and 0.14mm (0.01 inch) in diameter and usually deposited on hairs on the underside of leaves. Cucumeris adults and immatures are shipped with a bran carrier. They are available in two types of packaging: Bulk cartons, containing 10,000 – 50,000 predators. The contents are gently shaken onto leaves or placed on rock wool blocks or growing media in contact with the plant stem. Upon receipt active predators should be visible at the top of the containers. Slow release bags, containing approximately 30mL. (1/8 cup) of carrier with predators and a food source. The bags act as miniature breeding units and are hung on plants throughout the area. Over four weeks, each bag can produce over 1000 predators under good conditions.
Relatively high introduction rates are required because thrips can reproduce nearly twice as fast as Cucumeris and Cucumeris only feed on immature thrips, not adults. Rates will vary depending on crop and level of pest infestation. Typical rate is 5 predators per square foot.
Using bulk container 10-100 Cucumeris per plant weekly as needed. As a starter culture for young plants, place 25 Cucumeris per plant at the base of the stem as soon as they are planted out (Shifted).
Using slow release bags Greenhouse – 1 bag per 5 plants every 1-2 weeks, until there is 1 bag per plant in infested areas. Interior plantscapes – 1 bag per large plant, every 6-8 weeks. Hang bags within 10 inches of the growing point on greenhouse crops, ensuring good contact with the stem and leaves. Bags should not be exposed to direct sunlight or overhead watering.
A complete life cycle takes 10-12 days at 68° F. Newly hatched larvae do not feed until they molt at 2 days old. They feed for another 7 days before becoming adults. Adults live for up to 30 days.
Use Cucumeris along with other thrips predators such as Orius spp. and Hypoaspis. Pesticides and even wetting agents and spreader-stickers may adversely affect Cucumeris survival. Broad spectrum and systemic insecticides are toxic to Cucumeris.