Influence of soil-borne inoculum of plasmodiophora brassicae measured by qpcr on disease severity of clubroot-resistant cultivars of winter oilseed rape (Brassica napus l.)
2021 (English)In: Pathogens, E-ISSN 2076-0817, Vol. 10, no 4, article id 433Article in journal (Refereed) Published
Abstract [en]
Use of resistant cultivars is considered the most effective tool in managing clubroot. Three clubroot-resistant commercial winter oilseed rape (OSR) cultivars and a susceptible ‘Cultivar mix’ were evaluated for disease severity index (DSI) and yield performance in field soils, selected for varying abundance of natural inoculum of Plasmodiophora brassicae. Seven field trials were carried out during 2017–2019 in winter OSR crops, and comparative bioassays were performed in a growth chamber. Substantial variation in clubroot infection between years was observed in the field trials. For Cultivar mix, a negative correlation (y = −252.3ln(x) + 58,897.6) was found between inoculum density and seed yield in five trials, whereas no correlation was found for the resistant cultivars. In bioassays, Cultivar mix exhibited a significantly high correlation between DSIb and number of gene copies g−1 soil (R2 = 0.72). For resistant cvs., Mentor and Alister, correlation was R2 = 0.45 and 0.58, respectively, indicating that resistance was under pressure. In field trials, DSIf of the resistant cultivars was lower (<27). The recommendation is thus to use clubroot-resistant cultivars of OSR as part of Integrated Pest Management in situations where abundance of P. brassicae DNA exceeds 1300 gene copies g−1 soil. © 2021 by the authors.
Place, publisher, year, edition, pages
MDPI AG , 2021. Vol. 10, no 4, article id 433
Keywords [en]
Bioassays, Brassica napus, Clubroot, Disease severity index (DSI), Field trials, Real-time qPCR, Resistant cultivars, Soil-borne inoculum, Yield
National Category
Agricultural Science
Identifiers
URN: urn:nbn:se:ri:diva-53020DOI: 10.3390/pathogens10040433Scopus ID: 2-s2.0-85104261463OAI: oai:DiVA.org:ri-53020DiVA, id: diva2:1557466
Note
Funding details: Agricultural Research Foundation, ARF; Funding details: Stiftelsen Lantbruksforskning, SLF, O-16-20-765; Funding text 1: This research was funded by the Swedish Farmers? Foundation for Agricultural Research (grant number O-16-20-765), the Foundation for Swedish Oil Plant research and Carl Robert Prytz Donation fund.; Funding text 2: Funding: This research was funded by the Swedish Farmers’ Foundation for Agricultural Research (grant number O-16-20-765), the Foundation for Swedish Oil Plant research and Carl Robert Prytz Donation fund.
2021-05-262021-05-262021-05-26Bibliographically approved