ISSN:
1573-8469
Keywords:
Cucumis melo
;
Citrullus lanatus
;
dsRNA
;
muskmelon
;
mycovirus
;
watermelon
Source:
Springer Online Journal Archives 1860-2000
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Abstract Monosporascus root rot/vine decline (MRR/VD) causes root necrosis and severe stunting of muskmelon and watermelon plants in several countries around the world. MRR/VD is caused by the soilborne ascomycete fungus, Monosporascus cannonballus. Currently, there are few options available for control of MRR/VD. This research describes experiments to test the possibility of using naturally occurring M. cannonballus isolates containing double-stranded RNA (dsRNA) for the biological control of MRR/VD. These isolates often develop a degenerate phenotype characterized by slow growth and reduced ascospore production. In addition, these degenerate isolates are hypovirulent on muskmelon. Plants co-inoculated with a hypovirulent, dsRNA+ isolate (Tx93-449+) and a virulent, dsRNA- isolate (Az90-33-) at an inoculum ratio of 10 : 1 (hypovirulent : virulent) were indistinguishable from the uninoculated plants in greenhouse pathogenicity trials. In vitro infection assays using fluorescence microscopy on aniline-stained muskmelon roots suggested that although the hypovirulent dsRNA+ isolate Tx93-449+ penetrated and partially colonized roots of the seedlings, it was not as efficient in colonizing the roots as the virulent, dsRNA- isolate Az90-33-. While more extensive experiments are needed, these data suggest that hypovirulent dsRNA+ isolates of M. cannonballus have potential for development as biological control agents to reduce disease pressure associated with MRR/VD.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1008703410411
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