eCite Digital Repository
Symptomatology of crown rot of pyrethrum caused by Sclerotinia spp. in Tasmania, Australia
Citation
Scott, JB and Arvier, R and Pearce, TL and Pilkington, S and Pethybridge, SJ and Hay, FS, Symptomatology of crown rot of pyrethrum caused by Sclerotinia spp. in Tasmania, Australia, 2014 APS-CPS Joint Meeting - Abstracts of Presentations, 9-13 August, Minneapolis, Minnesota, pp. S3.105. (2014) [Conference Extract]
 | PDF (Scott, J. B., Arvier, R., Pearce, T. L., Pilkington, S., Pethybridge, S. J., and Hay, F. S. 2014. Symptomatology of crown rot of pyrethrum caused by Sclerotinia spp. in Tasmania, Australia, Phytopathology 104:S3.105) Pending copyright assessment - Request a copy 2Mb |
Abstract
Sclerotinia crown rot (SCR), caused by S. minor and S. sclerotiorum, is an
important disease affecting the vegetative tissues of pyrethrum (Tanacetum
cinerariifolium) during winter and spring. Symptoms of SCR include
bleaching and wilting of leaves leading to necrosis of vegetative tissues.
Under severe conditions plant death occurs. This study characterised the
progression of SCR symptoms and the relative differences between the two
species and forms of inoculums. The relative ability of sclerotia and
ascospores to initiate SCR infection was tested under greenhouse conditions.
Sclerotia of both species were demonstrated to infect the crown of pyrethrum
when myceliogenically germinating sclerotia were in direct contact with the
host plant. However, inoculation with ascosporic suspensions of either species
failed to initiate SCR symptoms. Under favourable conditions, symptom
expression was apparent at 2 to 3 days post inoculation (DPI) with the
occurrence of water soaked lesions in leaf tissues. From 20 DPI, infected
tissues typically appeared necrotic. Symptoms did not differ between the two
species. However, isolates of S. minor were more aggressive with a mean
proportion of necrotic leaves at 20 DPI of 0.34, relative to 0.16 (P = 0.01) for
S. sclerotiorum. Sclerotial formation by S. minor was also faster, producing
sclerotia within 13 DPI, while S. sclerotiorum required 28 DPI. These results
support field observations where S. minor is dominant.
Item Details
| Item Type: | Conference Extract |
|---|---|
| Keywords: | pyrethrum, Sclerotinia, crown rot |
| Research Division: | Biological Sciences |
| Research Group: | Plant biology |
| Research Field: | Plant pathology |
| Objective Division: | Plant Production and Plant Primary Products |
| Objective Group: | Horticultural crops |
| Objective Field: | Horticultural crops not elsewhere classified |
| UTAS Author: | Scott, JB (Dr Jason Scott) |
| UTAS Author: | Pearce, TL (Dr Tamieka Pearce) |
| UTAS Author: | Pilkington, S (Mrs Stacey Pilkington) |
| UTAS Author: | Pethybridge, SJ (Dr Sarah Pethybridge) |
| UTAS Author: | Hay, FS (Dr Frank Hay) |
| ID Code: | 100316 |
| Year Published: | 2014 |
| Deposited By: | Tasmanian Institute of Agriculture |
| Deposited On: | 2015-05-11 |
| Last Modified: | 2015-05-11 |
| Downloads: | 0 |
Repository Staff Only: item control page