Translator Disclaimer
1 July 2011 Mortality of the Cycad Aulacaspis Scale (Hemiptera: Diaspididae) by the Entomopathogenic Fungus Isaria fumosorosea Wize under Laboratory Conditions
Author Affiliations +
Abstract

The entomopathogenic fungus Isaria fumosorosea Wize (PFR97® strain, Certis USA, Columbia, MD) was tested as a mortality agent of the cycad aulacaspis scale, Aulacaspis yasumatsui Takagi, at 2 temperatures in the laboratory. First instars of A. yasumatsui were treated with 1 of 4 concentrations of I. fumosorosea (5.4 × 107, 9.9 × 106, 6.4 × 105, or 1.8 × 105 blastospores/ml of water) or a water only control. Following treatment, insects were held at either 20 or 30°C. The highest concentration treatment resulted in the highest mean infection rate at 8 d postapplication (73 ± 4.2% at 30°C; 84 ± 3.7% at 20°C). However, there was no interaction between blastospore concentration and temperature for infection rate. The lowest mortality rate was obtained with the highest concentration of blastospores under 20°C (13 ± 3%). The LC50 at 20° and 30°C were 6.1 × 106 and 5.3 × 106 blastospores/ml, respectively. The LT50 was lower at 30°C than at 20°C for the 3 highest concentrations. The radial growth of the fungus on potato dextrose agar 20 d after inoculation was 37% greater at 30°C than its radial growth at 20°C. These results indicate that I. fumosorosea may be a new biological control weapon for suppressing infestations of cycads by A. yasumatsui. This is the first report of I. fumosorosea being evaluated to infect an armored scale insect.

José A. Castillo, Pasco B. Avery, Ronald D. Cave, and Cecil O. Montemayor "Mortality of the Cycad Aulacaspis Scale (Hemiptera: Diaspididae) by the Entomopathogenic Fungus Isaria fumosorosea Wize under Laboratory Conditions," Journal of Entomological Science 46(3), 256-264, (1 July 2011). https://doi.org/10.18474/0749-8004-46.3.256
Received: 7 December 2010; Accepted: 1 February 2011; Published: 1 July 2011
JOURNAL ARTICLE
9 PAGES


SHARE
ARTICLE IMPACT
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top