Efficacy of Sclerotinia minor for dandelion control: effect of dandelion accession, age and grass competition

• Published in: Weed research Vol. 47; no. 1; pp. 63 - 72
• Main Authors: ABU-DIEYEH, M.H, WATSON, A.K
• Format: Journal Article
• Language: English
• Published: Oxford, UK Oxford, UK : Blackwell Publishing Ltd 01.02.2007; Blackwell Publishing Ltd; Blackwell Science
• Subjects: accessions; age; biocontrol; bioherbicide; Biological and medical sciences; biological control; Biological control and other methods; Chemical control; competition; Fundamental and applied biological sciences. Psychology; Parasitic plants. Weeds; Phytopathology. Animal pests. Plant and forest protection; Sclerotinia; Sclerotinia minor; synergy; Taraxacum officinale; turf grasses; turfgrass; Weeds; Competition; turfgrass; Monocotyledones; synergy; Plant pathogen; Biological control; Ornamental crop; Compositae; Synergism; Medicinal plant; Fungi; Gramineae; Dicotyledones; Weed science; Bioherbicide; Angiospermae; Taraxacum officinale; Sclerotinia minor; Ascomycetes; Biopesticide; biocontrol; Thallophyta; Weed; Pest and disease control; Pesticides; Herbicide; Turf; accessions; Spermatophyta; Lawn grasses; age
• ISSN: 0043-1737; 1365-3180
• DOI: 10.1111/j.1365-3180.2007.00542.x

Control of Taraxacum officinale (common dandelion) and other broad-leaved weeds in temperate turfgrass has been readily achieved with phenoxy herbicides. The herbicide option has been revoked through municipal and provincial legislation in many regions of Canada, necessitating alternative approaches. We examined the effects of dandelion accessions, age and grass competition on the performance of Sclerotinia minor (IMI 344141) as a biological control for dandelion in turfgrass. Disease symptoms were identical on all 14 different accessions of dandelion and the above- and below-ground biomass were reduced by 94% and 96%, respectively, with no difference among accessions. Foliar damage and dandelion mortality caused by S. minor was affected by plant age and the presence of grass competition. Dandelions of all ages were more severely affected by S. minor in the presence of grass competition. Grass competition had greater impact on foliar biomass, whereas the fungus had a greater impact on root biomass of newly established dandelions. In addition to competition for resources, we were hypothesised that the grass sward provides a microenvironment favouring the success of S. minor as a biological control agent of dandelion. Thus, proper management of the turfgrass environment may be complementary to the efficacy of S. minor as a biocontrol for dandelion.