The predatory bug, Orius laevigatus, belongs to the family Anthocoridae, which are minute pirate bugs. It is a small insect equipped with piercing-sucking mouthparts, and two pairs of wings, the front pair being partially rigid. Predatory bugs of the genus Orius are omnivorous, i.e. feed on pollen and plant sap as well as on live prey. Orius bugs show a preference for certain types of prey: they feed on various thrips species, aphids, whiteflies, mites and moth eggs. Different species of Orius are known as effective predators of western flower thrips and are found in areas of temperate climate. The species Orius laevigatus is found throughout the Mediterranean basin, from the Atlantic region of western Europe to the eastern Mediterranean, including Israel.

Since 1991, several species of Orius are commercially used throughout the world for thrips control, especially the western flower thrips. The adults generally dwell in flowers, while the larval stages can be also found on the foliage. Orius is observed on trees, shrubs, and in dozens of agricultural crops such as strawberries, sweet peppers, melons, beans, basil, cotton, alfalfa and corn.

Biology 
Orius has 7 developmental stages: egg, five larval (=nymphal) stages, and adult (the predatory bugs belong to the Hemi-metabola insects which do not develop through a pupal stage). The female lays its eggs in the plant tissue of the stem, fruit, petiole, and major veins on the underside of the leaves. The egg is almost completely embedded within the plant's tissue with only the cap-like upper part visible, which makes spotting it difficult. Upon being laid, the egg is colorless but later on it becomes milky-white. It measures about 0.4 mm x 0.13 mm. A hatched egg is characterized by the open lid through which the young larva has come out. During its lifetime, the female is capable of laying 120-150 eggs. The eggs are laid separately and after about 4 days at a temperature of 25°C, the first instar larva hatches, shiny and colorless. After a few hours, the larva takes on a yellowish hue that turns orange in the second and third larval stages. The fourth and fifth instars turn dark brown; their body shape resembles the adult.
 
The color of the adult is brown-black with gray spots. Male and female can be distinguished by the tip of their abdomen, which is pointed on the female. The female's ovipositor may be visible using a magnifying glass. Different species of the genus Orius can be distinguished from each other by comparing the male genitalia. Adults mate shortly after emergence, and 3-5 days following mating (depending on temperature), the female begins laying her first eggs.
The development time of the Orius depends a great deal upon temperature, food supply of suitable quality and quantity and to a lesser extent upon the type of crop or daylength. Supplement of pollen improves oviposition and development. The development time of Orius from egg to adult is about 16-18 days at 25°C. The adult lives for 3-4 weeks, the male having a shorter lifespan than the female. In all its developmental stages, Orius is able to hunt and kill its prey by sucking its body fluids. At a temperature of 20°C, O. laevigatus can kill about 2 western flower thrips a day, and when the pest population is high, the Orius will kill more thrips than required for its nutritional needs. Adult Orius has good flying capabilities and quick movement, which help considerably in finding new prey and in dispersing within the habitat.

APPLICATION
O. laevigatus is packed in a 100 cc bottle containing 500 predatory bugs out of which at least 50% are adults and the rest are 4th and 5th instar nymphs. The bugs are mixed in a vermiculite carrier. The material can be either dispersed from the bottle directly over the plants or applied by especially designed distribution boxes that are hung on the plants.
Prior to opening the bottle it should be turned gently, while in horizontal position, to allow proper mixing of the bugs in the vermiculite carrier.

Application of THRIPOR® should be carried out upon receipt either early in the morning or late in the afternoon, under relatively mild temperatures.It is not recommended to delay the application of THRIPOR®. However, if necessary the material can be stored for 24 hours at room temperature (13-25°C). In any case the bottle should never be left under direct sunlight.

About 20-30 days following its release (depending upon temperature) young nymphs of the first generation of O. laevigatus are expected to occur in the flowers. Together with adults of the original introduction, they will continue preying upon the thrips of all stages. Establishment of the predatory bug in the flowers ensures long term biological control of thrips with no need for subsequent introductions of the predator nor application of chemical corrective measures.

Since O. laevigatus is able to maintain itself on pollen, it is recommended to apply THRIPOR® preventively (prior to the occurrence of the pest) on crops with ample amount of pollen in the flowers (e.g. sweet pepper). Curative introductions of the predator should be exercised immediately upon spotting the first thrips. The number of predatory bugs to be introduced and the frequency of introductions should be determined according to the nature of the target crop and the level of infestation by thrips.

The predatory bug is susceptible (to a certain degree) to the common pesticides that are used to fight other pests in the crop. Therefore, before applying any pesticide, the user should consult Bio-Bee's field advisors and ask for updated information concerning side effects of pesticides on Orius.

Declaration:
Bio-Bee Sde Eliyahu Ltd. produces and markets biological products. Production is carried out using innovative techniques under controlled quality assurance standards such as ISO 9001:2000, as well as IOBC's international standards for mass-production of insects.
All products are tested to meet specification requirements before leaving the factory.
Bio-Bee is not responsible for the outcome of implementation in the field, as it has no control over the method of application, local conditions, treatment/storage of product not according to instructions, etc.