disease complex threatening avocado and landscapes trees in California
Polyphagous shot hole borer and Fusarium dieback: A generalist pest/disease complex threatening avocado and landscapes trees in California Akif Eskale...
Polyphagous shot hole borer and Fusarium dieback: A generalist pest/disease complex threatening avocado and landscapes trees in California Akif Eskalen, R. Stouthamer, P. Rugman-Jones, G. Douhan, M. Twizeyimana, S. Lynch, D. Wang, J. Mayorquin, A. Gonzalez, F. Na, L. Yeung Department of Plant Pathology and Microbiology & Department of Entomology University of California, Riverside Southern California Forest Pest Council, April 23, 2013
Polyphagous Shot hole borer (Euwallacea sp.)
Male Female 0.1 inch long
0.05 inch long
Beetle and fungi have symbiotic relationship
Fusarium sp.
Mycangium
Graphium sp.
Acremonium sp.
Euwallacea sp.
Beetle gallery and Fungal colony on the gallery wall
Beetle eggs and larvae in the gallery
Vascular discoloration caused by fungi
Situation in Israel, Oct. 2012
Calculating colony forming units of fungal species associated with PSHB
Abdomen
Head
Larvae
# of Colony Forming Unit per beetle 1200 1000
Fusarium sp.
800 600
Graphium sp.
400 200 0 Female Head
Female Abdomen
Male Head
Male Abdomen
Larvae
Lesion lenght (cm)
Pathogenicity test on Hass
14 12 10 8 6 4 2 0
Fusarium sp.
control
Graphium sp. Fusarium sp.
Control
Known
Known&distribu+on&of&Fusarium&&dieback/&Polyphagous& shot& hole& borer&in&southern& California&12/18/2012& distribution of PSHB/FD in Southern California
