Host range of Boreioglycaspis melaleucae Moore (Hemiptera: Psyllidae), a potential biocontrol agent of Melaleuca quinquenervia (Cav.) S.T. Blake (Myrtaceae), under quarantine

Research on the natural enemies of the Australian tree Melaleuca quinquenervia, a dominant, adventive weed of wetland habitats in south Florida, USA began in the late 1970s. Since then host-range tests have been conducted in Australia and Florida on three insect species: a weevil, a sawfly, and a psyllid. Herein we discuss the host-range studies of the psyllid, Boreioglycaspis melaleucae conducted in quarantine in Florida. Tests showed that the host range is very narrow, limited to one Melaleuca species, M. quinquenervia. One time, a few psyllids developed on a different species, Callistemon (=Melaleuca) citrinus, broad-leaf form, but repeated efforts to rear it again failed. In its Australian homeland, B. melaleucae has been collected on 5 closely related broad-leaved Melaleuca species including M. quinquenervia; it developed on 2 of 4 species tested, M. viridiflora (28%) and M. quinquenervia (37%). There was also 2% development on a 6th narrow-leaved Melaleuca species, M. nodosa. In the New World, there are no native Melaleuca species; in the United States, there is one introduced group, Callistemon (=Melaleuca), which is of commercial value and just one naturalized species, M. quinquenervia, which has no commercial value. Because of the near absence of Melaleuca species and B. melaleucae’s narrow host range and ability to severely damage or kill M. quinquenervia, we concluded that field release of B. melaleucae in south Florida would be safe. The first releases were made in February 2002.