diseases of Canola

Question 1

Sign and symptom

• blackleg
• verticillium stripe.

Answer 1

black leg
sign- black pycnidia
symptom- blackening of stem

vertililicim stripe
sign- microsclerotia (black dots)
symptom- stunting/ prematurance of plant

Question 2

write one symptom and one sign of

• white rust
• scleroinia stem rot

Answer 2

white rust
sign- powdery white pustules on underside of leaf
symptom- swollen, twisted and disoriented inflorescence

sclerotinia stem rot
sign- sclerotia bodies
symptom- ripen prematurely, becoming bleached, lesions on leaves

Question 3

give a name of a pathogen that isn’t able to culture into vitro and why?

Answer 3

white rust

obligate parasite, needs a live host to survive

Question 4

list 3 crops which are non hosts to sclerotia sclerotium

Answer 4

corn, wheat, oats

Question 5

what is the importance of disease forecasting?

how is petal testing important in sclerotinia stem rot disease forecasting?

Answer 5

disease forecasting- knowing the knowing the weather, field cropping and history of the field is important as well always scout the fields

Question 6

Scientific pathogen name for black leg

Answer 6

Leptosphaeria maculans

Question 7

scientific name for verticillium stripe in canola

Answer 7

Verticillium longisporum

Question 8

Disease management black leg of canola

Answer 8

scout the field 
grow resistant varieties
crop roatation
weed control 
use certified seed

Question 9

Disease management for Verticillium stripe in canola

Answer 9

crop rotation (3 yrs) 
weed control
develop on farm biosecurity 
no host resistance
very limited fungicide control

Question 10

Disease management for white rust in canola

Answer 10

crop roation 3 years
weed control
use resistant cultivars
use certified seed

Question 11

Sclerotinia Stem rot of canola Scientific pathogen name

Answer 11

Sclerotinia sclerotiorum

Question 12

Host for sclerotinia stem rot of canola

non host

Answer 12

sunflower, lentils, peas, beans, flax, alfalfa, potato

Non host- cereals and corn

Question 13

Sclerotinia stem rot of canola sign and symptoms

Answer 13

lesions on leaves and stem 
light brown lesions discoloured and watery 
bleached stem shatters and sheds
sclerotia in stem 
apothecia on ground

Question 14

Disease management for canola sclerotinia stem rot

Answer 14

avoid crowding to allow aeration
weed control
crop rotation
biological control