Field and laboratory studies on the fungus Aspergillus parasiticus, a pathogen of the pink sugar cane mealybug Saccharicoccus sacchari

• Published in: Biological control Vol. 1; no. 4; pp. 288 - 292
• Main Authors: Drummond, Jane, De Barro, Paul J., Pinnock, Dudley E.
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.12.1991
• Subjects: ANAGYRUS; ANAGYRUS SACCHARICOLA; ASPERGILLUS PARASITICUS; biological control; CACOXENUS PERSPICAX; DIPTERA; ENCYRTIDAE; ENEMIGOS NATURALES; ENNEMI NATUREL; METARHIZIUM ANISOPLIAE; NATURAL ENEMIES; PENICILLIUM; pink sugar cane mealybug; PSEUDOCOCCIDAE; QUEENSLAND; Saccharicoccus sacchari; SACCHARUM OFFICINARUM; SEASONAL VARIATION; sugar cane; TEMPERATURA; TEMPERATURE; VARIACION ESTACIONAL; VARIATION SAISONNIERE; pink sugar cane mealybug; Aspergillus parasiticus; Saccharum officinarum; Metarhizium anisopliae; Saccharicoccus sacchari; Cacoxenus perspicax; Anagyrus saccharicola; biological control; sugar cane
• ISSN: 1049-9644; 1090-2112
• DOI: 10.1016/1049-9644(91)90080-J

Infestation of sugar cane nodes by the mealybug Saccharicoccus sacchari (Cockerell) was studied in two commercial fields over a 7-month period in 1987. Natural enemies associated with S. sacchari were fungi Aspergillus parasiticus Speare, Metarhizium anisopliae (Metschnikoff) Sorokin, and Penicillium spp.; the dipteran Cacoxenus perspicax Knab; and the hymenopteran parasitoid Anagyrus saccharicola Timberlake. A. parasiticus was the predominent natural enemy of S. sacchari whereas all other natural enemies showed a low level of activity. The highest prevalence of A. parasiticus was in March when it occurred on 84% of S. sacchari-infested nodes. The prevalence of A. parasiticus declined rapidly during April and May and was absent in the winter months during which nodal infestation of S. sacchari increased. In laboratory bioassays all fungal isolates originating from S. sacchari were more virulent at 28°C than at 24°C. Laboratory studies supported the hypothesis based on field observations that temperature highly influenced the efficacy of A. parasiticus against S. sacchari.