pathogenesis and seedling diseases

Pathogenesis and Seedling Pathogenesis and Seedling DiseasesDiseases

LEARNING OBJECTIVES:

The Disease TriangleHeterotrophy and Pathogenesis

Saprotrophs, Necrotrophs, and BiotrophsGrowth and Reproduction of Fungi in PlantsSeedling Diseases

Damping-offFusarium root rotTop BlightPhytophthora root rot

PLANT DISEASE TRIANGLE

ENVIRONMENT

PATHOGEN

HOST

FOMITOPSIS PINICOLA

RED BELT CONK

“BROWN CRUMBLY ROT”

SAPROTROPHIC FUNGI

SYCAMORE ANTHRACNOSE

NECROTROPHIC PATHOGENS

POWDERY MILDEW

HYPHAE ASCOCARPS

BIOTROPHIC PATHOGENS

Growth of Fungi in Plants HYPHAE

PATHOGENESISPATHOGENESIS

TOXINSTOXINS

ENZYMESENZYMES

GROWTH REGULATORSGROWTH REGULATORS

RHYTISMA PUNCTATUM

ACER MACROPHYLLUM

Cedar root rotPhytophthora lateralis

Asexual Reproduction of Fungi

Oomycetes- Zoospores

Ascomycetes - Conidiospores

SWISS NEEDLE CAST

PHAEOCRYPTOPUS GAEUMANNII

Sexual Reproduction of Fungi

Ascospores

CROP ROTATION

FUMIGATION

PRECISION SOWING

PLANT DISEASE TRIANGLE

ENVIRONMENT

PATHOGEN

HOST

DAMPING OFF– PYTHIUM – a Watermold

HOSTENVIRONMENT

PATHOGEN

SPORANGIA Release Zoospores

SEXUAL OOSPORES

FUSARIUM ROOT ROT or 4TH OF JULY DISEASE– FUSARIUM OXYSPORUM

HOSTENVIRONMENT

PATHOGEN

TOP BLIGHT– PHOMA, FUSARIUM

HOSTENVIRONMENT

PATHOGEN

WINTER INJURY--ABIOTIC

“STORAGE BLIGHT” -- ABIOTIC

PHYTOPHTHORA ROOT ROT IN DOUGLAS-FIR

SPORANGIA

HOSTENVIRONMENT

PATHOGEN

OOSPORE

DAMPING OFF– PYTHIUM

HOSTENVIRONMENT

PATHOGEN

SPORANGIA

FUSARIUM ROOT ROT or 4TH OF JULY DISEASE– FUSARIUM OXYSPORUM