Midterm 1 Flashcards
Blackleg pathogen
leptospheria maculans - fungi
Blackleg hosts
- canola
2. cabbage, turnip, cauliflower
How common is seed infection from blackleg?
not very, but still a concern for international markets
resistance and susceptibility to disease (polish & argentine) to blackleg
polish - susceptible
Argentine - moderatley susceptible to resistant
asexual or sexual - blackleg
both
Disease cycle - blackleg
- sexual spores are produced on canola trash inside pseudothecia
- spores are released throughout growing season - airborne (long distance)
- asexual spores from pycnidia
- requires splashing in rain
- short distance
Control of blackleg
- 3-4 year rotation
- tillage
- pathogen free seed
- fungicides - elimination
- Genetic resistance
Signs of white rust
white, powdery pustules
symptoms of white rust
stagheads
obligate parasitic fungus
must have live host
pathogen of verticillium
verticillium longisporum
Symptoms of verticillium
black vertical stripes on stems
signs of verticillium
microsclerotia inside the stem later in season
is sclerotinia sexual or asexual?
sexual
non hosts of sclerotinia
corn, cereals
signs of sclerotinia
apothecia on ground
sclerotia in stem
symptoms sclerotinia
- stem rot
- lesions on leaves and stems
- bleached stems
sclerotinia pathogen
sclerotinia sclerotiorum - fungi
control of sclerotinia
- rotation
- resistance
- weed control
- certified seed
Biotic agents
living
- fungi, bacteria, viruses, phytoplasma, nematodes, insects
Abiotic agents
- unfavorable weather
- nutrient deficiencies
- toxic chemicals and pollutants
- genetic abnormalities
Biotic diseases
- bacteria
- fungi
- viruses
- nematodes
- phytoplasma