CH12 plant diseases

Question 1

Why are plant diseases dangerous

Answer 1

• people starve
• economies struggle
• jobs are lost

Question 2

Ring rot

Answer 2

• bacterial
• caused by gram-positive bacteria
• damages leaves, tubers and fruit
• once affects a field, cannot be used to grow crops again for at least 2 years

Question 3

Tobacco mosaic virus

Answer 3

• virus
• damages leaves, flowers and fruit
• stunts growth and reduces yields
• can lead to total crop loss
• no cure

Question 4

Potato blight

Answer 4

• fungus-like protoctist oomycete
• hyphae penetrate host cells, destroying leaves, tubers and fruit
• resistant strains, careful management and chemical treatments can reduce infection risk

Question 5

Black sigatoka

Answer 5

• caused by fungus
• attacks leaves
• hyphae penetrate and digest cells, turning them black
• leads to a 50% reduction of yield
• good husbandry and fungicide treatment can control spread of disease if no cure