Introduction. The Asian citrus psyllid, Diaphorina citri Kuwayama, is particularly harmful to
citrus plantations as it is one of the two psyllid vectors of the citrus greening disease or Huanglongbing. This
disease, which limits the longevity of trees, is due to an intracellular bacterium which mainly affects the phloem.
Past experience of biological control of D. citri in Reunion Island. In Reunion Island, this disease,
detected in 1967, was the main obstacle to the development of the cultivation of citrus fruit. Control of the vector
D. citri, by introducing from India and multiplying on site the specific parasitoid Tamarixia radiata
(Waterston), was carried out during 1978 when nearly 4600 adult parasitoids were released. The success of T.
radiata combined with the distribution of healthy plant material was at the origin of the revival of the cultivation of
citrus fruit in Reunion Island. Programme for a biological control of D. citri in Guadeloupe. In Guadeloupe,
D. citri was reported in January 1998. No trace of insect parasitism was found and only one fungus,
Hirsutella citriformis Speare, proved, under certain conditions, capable of regulating the populations of this
psyllid. Taking into account the experience in Reunion Island and that the greening disease has not shown up in
Guadeloupe, the introduction of T. radiata from Reunion Island was made in January 1999. About 1000 T.
radiata were released all over the Guadeloupe islands. At present, just a little more than 1 year after the last
releases, the parasitoid is established and present in almost all the citrus orchards where psyllid populations have
decreased considerably. Quite favorable biological characteristics play a great part in explaining the excellent
effectiveness of T. radiata in biological control programmes against D. citri.