ISSN:
1365-3059
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
A diseased isolate of Ophiostoma ulmi was found to contain 10 segments of double-stranded RNA (dsRNA) with molecular weights ranging from 2.40 x 106 to 0.23 x 106. In contrast seven other healthy isolates in the same vegetative compatibility group contained either no dsRNA or up to four dsRNA segments. Transmission of the disease to healthy isolates by hyphal anastomosis was accompanied by-transmission of the 10 dsRNA segments. In a genetic cross in which the diseased isolate acted as the female parent single-ascospore progeny were healthy and either contained no dsRNA or only one segment of dsRNA. When elm trees were inoculated with diseased isolates, subsequent reisolations were healthy and retained only two to seven of the dsRNA segments or were diseased and retained all 10 dsRNA segments. Following conidiogenesis a diseased isolate gave rise to single-conidial progeny which were either slow growing and diseased, like their parent, with all 10 dsRNA segments, or faster growing like healthy isolates. Some of the faster growing conidial isolates retained only two to seven of the dsRNA segments and were disease-free. However a majority of the faster growing conidial isolates retained all 10 dsRN A segments and were shown to carry the disease in a latent form. The possibility that the disease of O. ulmi is conferred by specific segments of dsRNA and the potential of d-factors for the control of Dutch elm disease are discussed.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1365-3059.1986.tb02016.x
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