Plant Disease Basics 2

Question 1

What are the three general symptoms of disease?

Answer 1

-Weekened or killed tissue.
- Abnormal in cell growth
- Whole plant apperance: Blight, stunted, dwarfing, wilts.

Question 2

Do all disease symptoms spread?

Answer 2

No. They can either be localized (stick to one area) or systemic (spread throughout the plant).

Question 3

What are primary and secondary symptoms?

Answer 3

Primary symptoms are at the infectious site and result in a direct response to the pathogen.
Secondary symptoms are a result of primary symptoms ex—wilting, chlorosis, etc.

Question 4

What is Blight?

Answer 4

It is a rapid decline of different parts of the plant. Parts of the plants start dying off.

Question 5

What kind of pathogen causes blight?

Answer 5

Bacteria

Question 6

What kind of pathogen causes leaf spots and fruit spots?

Answer 6

Bacteria

Question 7

What are the signs of leaf spots and fruit spots?

Answer 7

legions in the leaves or fruit that have the yellow halo around them.

Question 8

What kind of pathogen causes canker?

Answer 8

Fungi

Question 9

Where in the plant does canker occur?

Answer 9

Trunk, branches, and stems.

Question 10

What are some signs of canker?

Answer 10

Cracked lesions on twigs, kills the weedy part of the tree.

Question 11

What kinds of pathogens cause mosaic?

Answer 11

Viruses

Question 12

What is the sign of mosaic?

Answer 12

Leaves look like a mosaic of green, light green and yellow.

Question 13

What is the sign of corks?

Answer 13

Corky texture on plant roots.

Question 14

Briefly describe the disease damping off.

Answer 14

This disease leads to the death of seedlings caused by the decomposition of roots and stems.

Question 15

What kind of a pathogen caused damping off?

Answer 15

Fungi

Question 16

What kind of a pathogen causes galls?

Answer 16

Bacteria, fungus, nematode or other organisms.

Question 17

What are the signs of Galls?

Answer 17

Abnormal swelling or localized outgrowth.

Question 18

What kind of pathogens cause soft rots?

Answer 18

fungi and bacteria

Question 19

What is soft rots?

Answer 19

It is rotting of plant tissue as a result of fungal or bacterial infection. It affects the entire plant.

Question 20

What are angular leaf spots?

Answer 20

They are similar to lesions on a leaf but the spots are angular.

Question 21

What causes dieback?

Answer 21

Several abiotic factors like nutrition, water, weather and stem diseases, root diseases etc.

Question 22

What is a sign of dieback?

Answer 22

The plant dies back from newest growth to oldest growth.

Question 23

What disease is water soaking?

Answer 23

It is similar to angular leaf spots but instead of dead tissue, it looks like little water marks on the leaves.

Question 24

What is a sign of scab disease?

Answer 24

Crstaceous lesions on all parts of the plant.

Question 25

what is wilts?

Answer 25

Wilts is when the plant starts wilting due to lack of transport of water to the leaves. This can be caused by bacteria and fungi.

Question 26

What is the sign of Witches brooming?

Answer 26

All nodes get pushed to the top of the plant and it starts to look like a broom.

Question 27

What are the signs of leaf distortion?

Answer 27

Leaves being twisted, cupped rolled or deformed.

Question 28

What kind of pathogen usually causes cupping of leaves?

Answer 28

Bacteria.

Question 29

What is gummosis?

Answer 29

Gummosis is the disease where trees release gum like fluid that solidifies (Ambers)

Question 30

What is necrosis?

Answer 30

Dead tissue

Question 31

What is stunting?

Answer 31

Lack of growth

Question 32

What is leaf scorch?

Answer 32

It is the degradation of leaves from the outside in.

Question 33

What is Downy mildew?

Answer 33

It is a fungal disease in which fungus grows mostly along leaf veins. This is caused by oomycetes.

Question 34

What is Powdery mildew?

Answer 34

It is a fungal disease in which white powder grows on the plant and resembles powder. This is mostly composed of mycelium.

Question 35

What is mycelium?

Answer 35

Thread like growth on fungi.

Question 36

What do bacterial strands look like?

Answer 36

They look like white strands/cotton.

Question 37

What is ring rot?

Answer 37

Rotting that happens within a plant in the form of a ring.

Question 38

When did the potato famine in Ireland take place?

Answer 38

1845-1850

Question 39

What is the estimated cost of Fusarium Head Blight in Canada?

Answer 39

75 million dollars.