NURSERY DISEASE NOTES USDA FOREST SERVICE NORTHERN REGION FOREST HEALTH PROTECTION No. 164 May 2005 PATHOGENIC COMPARISONS OF FUSARIUM ISOLATES FROM DISEASED HAWAIIAN ACACIA KOA
نویسنده
چکیده
Thirty-two isolates of Fusarium from Hawaiian Acacia koa exhibiting wilt/dieback disease symptoms were compared for their pathogenic potential on young Douglas-fir germinants in controlled laboratory tests. Only three isolates (one each of F. oxysporum, F. solani, and F. subglutinans) exhibited low virulence. All others, including isolates of F. semitectum and F. equiseti, were non-pathogenic. All isolates were capable of colonizing succulent germinant tissues. Varying levels of root decay and post-emergence damping-off were caused by some test isolates. Many infected germinants survived without disease symptoms throughout the 14-day test. Fusarium isolates from Acacia koa, although capable of colonizing non-host plant tissues, may be specifically adapted to their koa hosts.
منابع مشابه
Nursery Disease Notes Usda Forest Service Northern Region Forest Health Protection
Nine different Fusarium species were isolated from Acacia koa seeds, seedpods, seedling stem and root tissues, rhizosphere soil and soil surrounding roots of diseased trees. Fusarium oxysporum, the cause of koa dieback and wilt, was not isolated from seeds or seedpods but was found most commonly on roots and soil near diseased koa seedlings. Fusarium subglutinans was the most common species iso...
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Fusarium isolates obtained from diseased koa plants, rhizosphere soil and seeds/seedcoats may or may not be pathogenic on young seedlings under greenhouse conditions. This includes isolates of F. oxysporum, the putative cause of koa wilt/dieback disease in Hawaii. We tested ten Fusarium isolates, comprising four different species, for their pathogenic potential on Acacia koa seedlings under gre...
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