PLANT DISEASES

Question 1

• the most common parasites causing plant disease
• usually produce spores which, when carried to a plant, can begin an
  infection
• common during wet, humid seasons

Answer 1

fungi/fungus disease

Question 2

• single-celled microscopic organisms
• can be carried from plant to plant by wind, rain splash, insects
  and machinery

Answer 2

bacteria

Question 3

(other names: anthracnose, scab, leaf blotch, shot hole) are usually rather
definite spots of varying sizes, shapes and colors. There is nearly always a distinctive
margin. Sometimes the spot, which may be caused by bacteria or fungi, is surrounded by
a yellow halo

Answer 3

leaf spots

Question 4

generally larger diseased areas than leaf spots and more irregularly
shaped

Answer 4

leaf blights

Question 5

often produce spots similar to leaf spots, but the spots are called “pustules.”

Answer 5

rusts

Question 6

a superficial, white to light grayish, powdery to mealy growth on
leaves, but may also occur on stems and flowers.

Answer 6

powdery mildew

Question 7

symptoms are pale yellow green to yellow areas on the upper leaf
surface; light gray to purplish moldy growth on the under surface of the leaf. Blue mold of
tobacco is a downy mildew disease

Answer 7

downy mildew