University of California

Studies of two parasites of olive scale, Parlatoria oleae (Colvée): III. The role of an autoparasitic aphelinid, Coccophagoides utilis Doutt, in the control of Parlatoria oleae (Colvée)


C. E. Kennett
C. B. Huffaker
G. L. Finney

Authors Affiliations

C. E. Kennett was Associate Specialist in the Experiment Station, Berkeley; C. B. Huffaker was Professor of Entomology and Entomologist in the Experiment Station, Berkeley; G. L. Finney was Specialist in Biological Control in the Experiment Station, Berkeley.

Publication Information

Hilgardia 37(9):255-282. DOI:10.3733/hilg.v37n09p255. March 1966.

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The olive scale, Parlatoria oleae, was first found in California in 1934 and has since become a major pest. Attempts to control this insect by biological means began with the introduction of the external parasite, Aphytis maculicornis, from Iran in 1952. Inconsistent control by A. maculicornis led to the introduction of two additional parasites from Pakistan in 1957. One of these, Coccophagoides utilis, became established in California.

Coccophagoides utilis is an internal parasite which attacks both scale generations which P. oleae produces each year. Adult female C. utilis which have been mated deposit female eggs only. Unmated females deposit male eggs only. Field results show C. utilis capable of destroying up to 50 per cent of each host generation. The two species of parasites working together have exhibited the ability to give excellent control of olive scale.

Literature Cited

Broodryk S. W., Doutt R. L. The biology of Coccophagoides utilis Doutt (Hymenoptera, Aphelinidae). Hilgardia. 1966. 37(9):233-54. DOI: 10.3733/hilg.v37n09p233 [CrossRef]

DeBach P., Sundby R. A. Competitive displacement between ecological homologues. Hilgardia. 1963. 34(5):105-66. DOI: 10.3733/hilg.v34n05p105 [CrossRef]

Doutt R. L. An evaluation of some natural enemies of olive scale. Jour. Econ. Ent. 1954. 47(1):39-43.

Doutt R. L. A taxonomic analysis of parasitic Hymenoptera reared from Parlatoria oleae (Colvée). Hilgardia. 1966. 37(9):219-31. DOI: 10.3733/hilg.v37n09p219 [CrossRef]

Flanders S. E. Ovipositional instincts and developmental sex differences in the genus Coccophagus. Univ. of Calif. Pub. Ent. 1937. 6(15):401-22.

Huffaker C. B., Kennett C. E., Finney G. L. Biological control of olive scale, Parlatoria oleae (Colvée), in California by imported Aphytis maculicornis (Masi) (Hymenoptera: Aphelinidae). Hilgardia. 1962. 32(13):541-636. DOI: 10.3733/hilg.v32n13p541 [CrossRef]

Smith H. S. Multiple parasitism: Its relation to the biological control of insect pests. Bul. Ent. Res. 1929. 20(2):141-49. DOI: 10.1017/S0007485300021040 [CrossRef]

Turnbull A. L., Chant D. A. The practice and theory of biological control of insects in Canada. Canad. Jour. Zool. 1961. 39(5):697-753. DOI: 10.1139/z61-071 [CrossRef]

Zinna G. Ricerche sugli insetti entomofagi. III. Specializzazione entomoparassitica negli Aphelinidae: Interdipendenze biocenotiche tra due specie associate. Studio morfologico, etologico e fisiologico del Coccophagoides similis (Masi) e Azotus matritensis. Mercet. Bol. Bol. Lab. Ent. Agr. Portici. 1962. 20:73-184.

Kennett C, Huffaker C, Finney G. 1966. Studies of two parasites of olive scale, Parlatoria oleae (Colvée): III. The role of an autoparasitic aphelinid, Coccophagoides utilis Doutt, in the control of Parlatoria oleae (Colvée). Hilgardia 37(9):255-282. DOI:10.3733/hilg.v37n09p255
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