Measuring Quantitative Virulence in the Wheat Pathogen Zymoseptoria tritici Using High-Throughput Automated Image Analysis
Open Access
- 1 September 2014
- journal article
- research article
- Published by Scientific Societies in Phytopathology®
- Vol. 104 (9), 985-992
- https://doi.org/10.1094/phyto-11-13-0328-r
Abstract
Zymoseptoria tritici, causal agent of Septoria tritici blotch on wheat, produces pycnidia in chlorotic and necrotic lesions on infected leaves. A high-throughput phenotyping method was developed based on automated digital image analysis that accurately measures the percentage of leaf area covered by lesions (PLACL) as well as pycnidia size and number. A seedling inoculation assay was conducted using 361 Z. tritici isolates originating from a controlled cross and two different winter wheat cultivars. Pycnidia size and density were found to be quantitative traits that showed a continuous distribution in the progeny. There was a weak correlation between pycnidia density and size (r = −0.27) and between pycnidia density and PLACL (r = 0.37). There were significant differences in PLACL and pycnidia density on resistant and susceptible cultivars. In all, >20% of the offspring exhibited significantly different pycnidia density on the two cultivars, consistent with host specialization. Automated image analysis provided greater accuracy and precision compared with traditional visual estimates of virulence. These results show that digital image analysis provides a powerful tool for measuring differences in quantitative virulence among strains of Z. tritici.Keywords
This publication has 38 references indexed in Scilit:
- Application of Image Analysis in Studies of Quantitative Disease Resistance, Exemplified Using Common Bacterial Blight–Common Bean PathosystemPhytopathology®, 2012
- Characterization and Mapping of Oat Crown Rust Resistance Genes Using Three Assessment MethodsPhytopathology®, 2007
- Sexual reproduction facilitates the adaptation of parasites to antagonistic host environments: Evidence from empirical study in the wheat-Mycosphaerella graminicola systemInternational Journal for Parasitology, 2007
- SELECTION FOR RECOMBINATION IN SMALL POPULATIONSEvolution, 2001
- Inheritance of partial resistance to Septoria tritici in wheat (Triticum aestivum): limitation of pycnidia and spore productionAgronomy for Sustainable Development, 1997
- Recombination load associated with selection for increased recombinationGenetics Research, 1996
- A Field Disease Evaluation Method for Selecting Wheats Resistant to Mycosphaerella graminicolaPlant Breeding, 1992
- The assessment of infectious disease for brown rust (Puccinia hordei) of barleyPlant Pathology, 1991
- Resistance in Soft Red Winter Wheat toMycosphaerella graminicolaPhytopathology®, 1982
- Estimation of resistance of three wheat cultivars to Septoria tritici using a chemical method for determination of fungal myceliumTransactions of the British Mycological Society, 1977