751-4505-00L  Plant Pathology II

SemesterSpring Semester 2021
LecturersB. McDonald
Periodicityyearly recurring course
Language of instructionEnglish


AbstractPlant Pathology II focuses on disease control in agroecosystems based on biological control, pesticide applications and breeding of resistant crop cultivars. The genetics of pathogen-plant interactions will be explored in detail as a basis for understanding the development of boom-and-bust cycles and methods that may be used to prevent the evolution of pathogen virulence and fungicide resistance.
ObjectiveAn understanding of the how biological control, pesticides and plant breeding can be used to achieve sustainable disease control. An understanding of the genetic basis of pathogen-plant interactions and appropriate methods for using resistance to control diseases in agroecosystems.
ContentPlant Pathology II will focus on disease control in agroecosystems based on biological control, pesticide applications and breeding of resistant crop cultivars. The genetics of pathogen-plant interactions will be explored in detail as a basis for understanding the development of boom-and-bust cycles and methods that may be used to prevent the evolution of pathogen virulence and fungicide resistance.

Lecture Topics and Tentative Schedule

Week 1 Biological control: biofumigation, disease declines, suppressive soils.

Week 2 Biological control: competitive exclusion, hyperparasitism.

Week 3 Chemical control: History of fungicides in Europe, fungicide properties, application methods.

Week 4 Fungicide categories and modes of action, antibiotics, fungicide development, fungicide safety and risk assessment (human health).

Week 5 Resistance to fungicides. Genetics of fungicide resistance, ABC transporters, risk assessment, fitness costs. FRAC risk assessment model vs. population genetic risk assessment model.

Week 6 Genetics of pathogen-plant interaction: genetics of pathogens, genetics of plant resistance, major gene and quantitative resistance, acquired resistance. Flor's GFG hypothesis and the quadratic check, the receptor and elicitor model of GFG, the guard model of GFG.

Week 7 Resistance gene structure and genome distribution, conservation of LRR motifs across eukaryotes. Genetic basis of quantitative resistance. QTLs and QRLs. Connections between MGR and QR. Durability of QR.

Week 8 Genetic resistance: Costs, benefits and risks.

Week 9 Non-host resistance. Types of NHR. NHR in Arabidopsis with powdery mildews. NHR in maize and rice. Avirulence genes and pathogen elicitors. PAMPs, effectors, type-III secretion systems, harpins in bacteria. Fungal avirulence genes.

Week 10 Easter holiday no class.

Week 11 Sechselauten holiday no class.

Week 12 Host-specific toxins. GFG for toxins and connection to apoptosis. Fitness costs of virulence alleles. Diversifying selection in NIP1.

Week 13 Boom and bust cycles for resistance genes and fungicides and coevolutionary processes. Pathogen genetic structure and evolutionary potential. Genetic structure of pathogen populations in agroecosystems, risk assessment for pathogen evolution and breeding strategies for durable resistance.

Week 14 Resistance gene and fungicide deployment strategies for agroecosystems.

Week 15 Genetic engineering approaches to achieve disease resistant crops.
Lecture notesLecture notes will be available for purchase at the cost of reproduction.
LiteratureLecture notes will be available for purchase at the cost of reproduction.
Prerequisites / NoticePlant Pathology I provides a good preparation for Plant Pathology II, but is not a prerequisite for this course.