Xie, G.L., Pan, W.Y., Tang, Z.Y., Ding, D.C., & Lian, J.H. 1997 [Evaluation on the effective and stable control of Hemiberlesia pitysophila Takagi with Coccobius azumai Tachikawa.]. Acta Entomologica Sinica 40: 135-144.

Notes: The aphelinid Coccobius azumai, introduced from Okinawa, Japan, was first released and successfully established in Huidong County, Guangdong Province, China, in 1989. Systematic observations and investigations made since the initial release showed that a year later the parasitism rate of C. azumai on Hemiberlesia pitysophila reached 55.8-64.2% within 50 m of the release site, and the density of female H. pitysophila was reduced from 3.41 to 0.64 per needle. Two years later, the effective control radius had increased to about 300 m. The parasitism rate ranged from 20.8 to 32.9%. The density of female H. pitysophila was further reduced to 0.6 per needle. Both C. azumai and H. pitysophila stabilized at a low density, whereas in areas where no C. azumai were released, the density of female H. pitysophila increased from 3.4 to 4.22 per needle, which was 6-10 times higher than that observed in the release area. It was concluded that hyperparasitism of C. azumai by Marietta carnesi was only 3.1-5.3%, and had little influence on the control efficacy of C. azumai.