African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 5227

Full Length Research Paper

Acaricidal activity of Hypocrella raciborskii Zimm. (Hypocreales: Clavicipitaceae) crude extract and some pure compounds on Tetranychus urticae Koch (Acari: Tetranychidae)

Suradet Buttachon1, Angsumarn Chandrapatya1*, Winanda Himaman2 and Anake Kijjoa3
1Departmant of Entomology, Faculty of Agriculture, Kasetsart University, Chatuchak, Bangkok 10900, Thailand. 2Forest and Plant Conservation Research Office, Department of National Parks, Wildlife and Plant Conservation, Bangkok 10900, Thailand. 3ICBAS - Instituto de Ciências Biomédicas de Abel Salazar - CIIMAR, Universidade do Porto, 4099-003, Porto, Portugal
Email: [email protected]

  •  Accepted: 07 February 2013
  •  Published: 12 February 2013

Abstract

The acaricidal activity of secondary metabolites from an entomopathogenic fungus,Hypocrella raciborskii Zimm. in controlling two-spotted spider mite, Tetranychus urticaeKoch (Acari: Tetranychidae) is explored in this study as a new agent for pest control. The crude extract was prepared in ethyl acetate. Secondary metabolites were elucidated using Nuclear Magnetic Resonance and High-Resolution Mass Spectrometry analysis. The major secondary metabolites of the crude extract were ergosterol, dustanin (15α, 22-dihydroxyhopane) and 3β-acetoxy-15α,22-dihydroxyhopane. The crude extract and pure compounds were used to determine their toxicity, repellency and oviposition deterrence against T. urticae, under the laboratory conditions. Crude extract of 3% w/v showed a strong contact toxicity (97% mortality, one day after treatment) and residual toxicity (80%, three days after treatment). Ergosterol induced 75% mite mortality in a residual toxicity bioassay. Females topically sprayed with 3% crude extract had their egg production reduced by 97%. Direct spraying of 3β-acetoxy-15α, 22-dihydroxyhopane and dustanin reduced egg production of T. urticae by 71 and 70%, respectively. Both crude extract and pure compounds had relatively slight repellency effect on T. urticae.

 

Key words: Fungal metabolites, bioassay, two-spotted spider mite