Results
We hope you enjoyed the quiz and learned something!
See how your score matches up…
1-3: You need to do a few more of these quizzes to become a field diagnostics expert.
3-5: You have made a start in your field diagnostics but there is some way to go…
5-7: You are getting more right than wrong so keep on learning!
7-9: Impressive you are getting pretty experienced in your field diagnostics!
10: Well done! But make sure you do the quiz again next month.
We hope you enjoyed the quiz and learned something!
See how your score matches up…
1-3: You need to do a few more of these quizzes to become a field diagnostics expert.
3-5: You have made a start in your field diagnostics but there is some way to go…
5-7: You are getting more right than wrong so keep on learning!
7-9: Impressive you are getting pretty experienced in your field diagnostics!
10: Well done! But make sure you do the quiz again next month.
#1. What is causing these pale spots on this bean leaf?
The correct answer is:
Rust fungus
The brown rusty coloured pustules are clearly visible in the more advanced stages. The small pale dots are also infection sites but the pathogen has not yet broken through the leaf epidermis (the tough layer of cells that creates the leaf surface).
The incorrect answers were:
Sucking insect probing
Many sucking pests, aphids, mealybugs, scale etc., do not create any damage at the site of penetration. Some pests do leave marks, but often they are necrotic and not pale like this.
Viral infection; a local lesion host
A local lesion host is a concept familiar to many who have worked with viruses but it is not often seen in the field. The rust pustules give away the real cause.
Herbicide spray damage
Symptoms can appear spattered across the leaf like this, but normally those that create an extremely localised response (e.g., paraquat) produce necrotic spots, not pale ones such as these.
