Amblyseius cucumeris is a beige predatory mite of less than 1 mm. As an arachnid it has eight legs. In spite of its modest appearance, it is still quite conspicuous because of its mobility on the underside of a leaf or in the flower.

The female mite mates several times. She deposits a few eggs daily on leafhairs close to the veins on the underside of the leaf. The young larvae that emerge have only six legs and do not eat. During the two subsequent nymphal stages and as an adult, they have eight legs. A nymph looks like a smaller adult, so there is no metamorphosis. The development from egg to adult takes 8-11 days (at resp. 25°C (77°F) and 20°C (68°F). An adult Amblyseius cucumeris lives for about 3 weeks.

Adult Amblyseius cucumeris pierce their prey and suck them empty. Besides thrips larvae, they might sometimes eat spider mites or eggs or larvae of the spider mite predator Phytoseiulus persimilis. As adult thrips can defend themselves well by striking out their abdomen, Amblyseius prefers first instar thrips. Moreover, they eat pollen, which is an interesting characteristic for preventative introduction of Amblyseius cucumeris in pollen bearing crops such as sweet pepper.

Amblyseius cucumeris has been used for years in several greenhouse vegetables crops such as sweet pepper, cucumber and eggplant. Also in ornamentals such as gerbera, chrysanthemum, rose and all sorts of pot plants, the interest for this predatory mite has increased during the last years. Although Amblyseius controls thrips well in a wide range of greenhouse crops, the leaf structure or composition of some plants (tomato, geranium) hampers the use of this predatory mite. Do therefore consult your technical advisor for possible applications.

A low air humidity (below 65%) impedes the population build-up of Amblyseius cucumeris as the eggs do not hatch anymore and breeder packs (see below) dry out. Therefore, Amblyseius cucumeris is assisted in the summer by other natural enemies of thrips (Orius, Amblyseius degenerans). In cucumber e.g., it has been shown that low humidity does not affect the mite too much due to a favourable micro-climate on the cucumber leaf.

Biobest offers Amblyseius cucumeris in the following formulations:

	Amblyseius-System: The predatory mites are packed per 10.000, 25.000 or 50.000 adults in a practical 1 litre sprinkler tube on a bran carrier. Through a dosage lid the mites are spread on the leaves. Amblyseius-System can also be obtained in 5 litre buckets containing 100.000 mites per bucket.
	Amblyseius-Breeding-System (ABS): This consists of breeder sachets that are simply hung in the crop without having to open them. A breeder sachet contains bran on which a fungus grows that serves as food for bran mites. These bran mites are on their turn eaten by Amblyseius. One breeder box contains about 1.000 predatory mites and can still produce thousands more for several weeks. The mites leave the breeder sachet gradually and spread throughout the crop. With this system Amblyseius can now also be introduced preventively in crops without pollen production such as cucumbers.
	ABS-material: This consists of the same material as ABS-System but is delivered as loose pupae in a 5 litre bucket. The material is introduced in heaps on the rock wool pot.
	Amblyseius-Vermiculite-System: This formulation is especially developed to blow Amblyseius cucumeris in the crop with a sprayer. This system is delivered per 10.000 and 25.000 mites per litre. This application method is particularly useful for ornamentals.
	Amblyseius-Slow-Release (ASR): This systems is identical to ABS-System, but the difference is that the predatory mites hatch from these breeder sachets over a longer period. Especially in periods with few thrips development (in winter time) this system offers a longer protection against thrips than the traditional ABS-System. Amblyseius cucumeris can be shortly stored at 15°C, if necessary.

Amblyseius-System: Introduce the predatory mites preventatively (before the presence of thrips). Consult the Biobest introduction scheme concerning the number to be introduced. Introduce the predatory mites as soon as possible after delivery. The material may be stored for a short period. Store the tubes in a dark place at 10-15°C and at a relative humidity of at least 85%. Allow the mites in the tube to adjust to ambient temperature before use. Turn and shake the tube slightly in order to distribute the predatory mites equally in the bran. The predatory mites should be sprinkled equally throughout the plants. Sprinkle the material (predatory mites + bran) on the leaves or in small piles on the rockwool cube (at the opposite site from the sprinkler). On the rockwool cube the predatory mites continue to develop for a few weeks (humid environment). The predatory mites develop well when relative humidity is at least 65%.

Amblyseius-Breeding-System: The Amblyseius-Breeding-System should be used preventatively (before the presence of thrips). Consult Biobest's introduction scheme concerning the number to be introduced. The predatory mites should be introduced as soon as possible after delivery. They may be stored for a short period at ca. 20°C and at a relative humidity of at least 85%. Distribute the boxes equally. Attach them to the stalks of the plants by using the hangers on top of the boxes. The predatory mites leave the cardboard boxes through the openings. Do not open the boxes, otherwise they will dry out too soon. In order to ensure a good development of the predatory mites, the relative humidity should be at least 65%.

Note: Several pesticides have a negative effect on Amblyseius cucumeris. Please be careful when controlling diseases and other pests. Consult Biobest's list of side-effects of pesticides on beneficial organisms.

The products Amblyseius-Breeding-System (ABS) and Amblyseius-Slow-Release-System (ASR), which contain the predatory mite Amblyseius cucumeris is delivered in breeding sachets, also contain Mold mites (Tyrophagus putrescentiae) and bran. Under certain circumstances such as a moist greenhouse climate or when using large quantities of breeding sachets, Mold mite population can increase to the point of causing damages in some crops (e.g. cucumbers). When planning to use these products in crops where they have never been used before, we recommend to first perform a small-scale trial or to discuss this with your Biobest advisor or supplier.

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