Biology and Feeding Habits of Orius tristicolor (Hemiptera: Anthocoridae)1

Studies were conducted on the biology of Orius tristicolor White at various temperatures and photoperiods. The lima bush bean, Phase olus limensis , was used as a host plant for the Pacific spider mite, Tetranychus pacificus McGregor which was the host for O. tristicolor in feeding Studies. Orius females usually mated soon after emergence from the 5th instar and began oviposition 2–3 days later. O. tristicolor eggs were usually laid in the bean leaf petiole, and the female laid an average of 129±12 eggs during her life span. Some descriptive information is given on the egg, nymphs, and adults. The life span of Orius adults was markedly shortened where bean leaves were the only food. O. tristicolor nymphal development required about 26, 14, and 8.5 days at 21.1, 25.5, and 33.3°C, respectively. Adult Orius longevity was about 35 days at 25.5°C with 12 hours light and 12 hours dark per day, with mites as food. There was a high degree of cannibalism by Orius adults when they were placed in cages with nymphs, despite the presence of mites as food.