The Relative Importance of Nitidulade Beetles and Bark Beetles in Transmission of Oak Wilt

2005 | Maya Hayslett and Jennifer Juzwik, University of Minnesota and USDA Forest Service

The oak wilt fungus, Ceratocyctis fagacearum, is transmitted in two ways. It travels through common root systems to infect neighboring trees of the same species and is transmitted long distance (called overland transmission) by insect vectors. Common insect vectors are beetles in the family Nitidulidae and oak bark beetles in the genus Psuedopityophthorus. Studies were performed in 2005 and 2006 to determine the beetle species involved in transmission of the fungus in Missouri and Texas. From this data, we hypothesize that Colopterus truncatus, Co. niger and Co. semitectus are vector species during the spring in Missouri and that the period of greatest risk for transmission is April and May with less risk in June. Co. truncatus was identified as a vector in Texas although other species may be involved. Psuedopityophthorus pruinosis, while present, could not be conclusively determined to be a vector in Texas. Co. truncatus appears to be a vector across the range of the disease while the involvement of other nitidulid beetle species varies with location. The contribution of oak bark beetles to the spread of the disease also varies with location.

Year: 2005

Funding Duration: 1-3 years

Grant Program: John Z Duling

Grant Title: The Relative Importance of Nitidulid Species and Bark Beetles in the Transmission of the Oak Wilt Fungus, Ceratocystis fagacearum, in Texas and Missouri

Researcher: Maya Hayslett

Key words: oak wilt; Nitidulid beetles; insect vectors

Peer Reviewed Publications from Grant:

  • Hayslett, M., Juzwik, J., and Moltzan, B. 2008. Three Colopterus beetle species carry the oak wilt fungus to fresh wounds on red oak in Missouri. Plant Dis. 92:270-275. View the Publication >
  • Hayslett, M., Juzwik, J., Moltzan, B., Appel, D., and Camilli, K. 2009. Insect vectors of the oak wilt fungus in Missouri and Texas. Pp. 103-114. In:  R.F. B Billings, R.F., and D.N. Appel (eds.), Proceedings of the National Oak Wilt Symposium, June 4-7, 2007, Austin, TX.  Texas Forest Service Publication 166. 267 pp. View the Publication >
  • Hayslett, M.C. 2007. The relative importance of Nitidulid beetle species and oak bark beetle species in the transmission of the oak wilt fungus, Ceratocystis fagacearum, in Missouri and Texas. M.Sc. Thesis, University of Minnesota, St. Paul. 86 p.

General Audience/Trade Publications: none

Presentations: none

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