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ARS Home » Midwest Area » Peoria, Illinois » National Center for Agricultural Utilization Research » Crop Bioprotection Research » Research » Publications at this Location » Publication #332345

Title: Screening of bacteria for antagonistic activity against phytopathogens of avocados

item Dunlap, Christopher
item Lueschow, Shiloh
item CARILLO, DANIEL - University Of Florida
item Rooney, Alejandro - Alex

Submitted to: Plant Gene
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/28/2016
Publication Date: 9/1/2017
Publication URL:
Citation: Dunlap, C.A., Lueschow, S.R., Carillo, D., Rooney, A.P. 2017. Screening of bacteria for antagonistic activity against phytopathogens of avocados. Plant Gene. 11:17-22.

Interpretive Summary: ARS researchers from Peoria, IL collaborated with a scientist from The University of Florida to identify bacteria that may be useful to control emerging diseases in avocados. The study screened for beneficial bacteria to control the fungal pathogens that cause Laurel wilt and Fusarium dieback in avocados. The study of four bacteria capable of antagonizing the pathogens in lab based assays. Two of the bacterial species identified were not known previously to be useful in controlling plant pathogens. This research benefits U.S. farmers and consumers that are impacted by these diseases of avocados.

Technical Abstract: Bacteria and fungi were isolated from the bark of the avocado tree (Persea americana) located in southern Florida. The bacterial strains were subsequently assayed for antagonism activity against Raffaelea lauricola, the causal agent of laurel wilt in avocados. The screen identified no isolates that could antagonize the phytopathogen. A collection Bacillales species were then screened for antagonism activity against R. lauricola. The assay identified 50 out of 180 strains as strong antagonists. Fifteen of the most active strains were evaluated for antagonism of Fusarium euwallaceae, the causal agent of Fusarium dieback in avocados. Four strains representing three Paenibacillus species and one Bacillus species were found to be active against both phytopathogens. This study is the first to report antifungal or antagonist activity of Paenibacillus thiaminolyticus or Paenibacillus apiaries against a phytopathogen. These results are the first steps in identifying possible bacteria that can be utilized as biocontrol agents against these important diseases of avocados.