Search

A colony of the encyrtid wasp Psyllaephagus euphyllurae (Masi) (Hymenoptera, Encyrtidae) has been established in the quarantine laboratory at the University of California, Riverside, California, USA as part of a classical biological control program against its invasive host, the olive psylla, Euphyllura olivina (Costa) (Hemiptera, Psylloidea, Liviidae), an important pest of olives in some parts of the world. The colony originators were reared from the same host found on abandoned, commercial olives in Catalonia, Spain; additional collections were made in Murcia. The parasitoid reproduces primarily by thelytoky; however, a few occasional males have been found in the field in Spain, but not in colonies reared under quarantine or laboratory conditions. Here, the female of P. euphyllurae is redescribed and its male is described and illustrated for the first time; the only previous mention of male P. euphyllurae was from Tunisia, reared from the same psyllid host but without any details on its morphology. A lectotype is designated for Encyrtus euphyllurae Masi. Information is given on the results of genetic matching between the two sexes of the parasitoid and also on the presence of the bacterial Wolbachia symbiont that apparently is affecting reproduction of this species, including its sex ratio in the field. Two species of hyperparasitoids have also emerged from the parasitized olive psylla nymphs from Catalonia: numerous specimens of Apocharips trapezoidea (Hartig) (Hymenoptera, Figitidae) and one specimen of a Pachyneuron sp. (Hymenoptera, Pteromalidae). [ABSTRACT FROM AUTHOR]

We examined the movement of aphelinid parasitoids from overwintering refuges into adjacent crops of cantaloupe and cotton. Eretmocerus eremicus and Encarsia spp. are important parasitoids attacking Bemisia tabaci Biotype B in the desert agricultural region of southeastern California. Movement was studied by marking naturally occurring field populations of parasitoids with rubidium chloride (RbCl). Two experimental study sites, each composed of natural enemy refuge strips and adjacent crops of cantaloupe and cotton, were grown for 2 years. Marking studies using RbCl demonstrated that the refuge strips supported early-season parasitoids which later migrated into adjacent crops. Between 15 - 63% of Eretmocerus eremicus caught in adjacent cotton and cantaloupe originated from the natural enemy refuges. Between 40 - 75% of aphelinids attacking B. tabaci in natural enemy refuges were Encarsia spp. while 98% of the marked, captured parasitoids in adjacent cotton and cantaloupe were Eretmocerus spp. Refuges produced higher numbers of whiteflies, relative to parasitoids, during spring months, showing the importance of refuge plants selective for natural enemies. This is the first known study using the marker RbCl that shows movement of naturally occurring Eretmocerus between an overwintering location and an adjacent crop. [ABSTRACT FROM AUTHOR]