AGH 483
Quiz 10
8 Nov 2004
Guest Speaker Dr. Laszlo Kovacs—Agrobacterium tumefaciens: Causal Agent of Crown
Gall Disease
Multiple choice. Please read the question carefully then write the letter of the answer that best completes the statement on the line
in front of the question. Each question is worth 1 point.
______1.
What chemical weapon is used by most pathogenic bacteria that cause rot
diseases?
A. Enzymes.
B. Hormones.
C. Polysaccharides.
D. Proteins.
______2.
The most common cause of wounds that serve as entry sites for A.
tumefaciens is
A. Cultivation damage.
B. Grafting.
C. Insect damage.
D. Winter freeze damage.
True/false questions. Please read each question carefully, then on the line next to the question write T if the statement is true or
F if the statement is false. Each question is worth 1 point.
______3.
Agrobacterium tumefaciens can transform a plant cell only if the cell is in
the healing phase after a wound.
______4.
Crown Gall Disease usually occurs in woody plant species but seldom in
annuals.
______5.
Agrobacterium radiobacter Strain K84, which produces the antibiotic
agrocin 84, is effective at curing plants infected with Crown Gall Disease.
Chapter 12. Bacteria and Mollicutes
Multiple choice. Please read the question carefully then write the letter of the answer that best completes the statement on the line
in front of the question. Each question is worth 1 point.
______6.
Fire
A.
B.
C.
D.
blight is caused by the bacterium
Clavibacter michiganense.
Erwinia amylovora.
Pseudomonas syringae.
Xanthomonas campestris.
______7.
Yellows diseases are caused by
A. Bacterial leaf blight pathogens.
B. Fastidious vascular bacteria.
C. Ice nucleating agents.
D. Spiroplasmas or phytoplasmas.
______8.
Water-soaked spots, with or without a yellow halo, are a common
symptom seen on plant leaves or fruit infected by bacteria. These spots
probably look water-soaked (or greasy) because
A. Bacteria destroyed cells and cell contents have leaked out.
B. Saphrophic pathogens are attacking the plant tissue.
C. The plant and pathogen are entering into a symbiotic relationship.
D. The plant is defending itself against the bacteria by depositing oily
substances around sites of infection.
Miscellaneous
Short answer.
9.
What has been your favorite lecture so far this semester? Why?
10. What has been your least favorite lecture so far this semester? Why?
AGH 483
Quiz 11
22 Dec. 2004
______1.
The filamentous body of a fungus is called
A. Apothecium.
B. Conidium.
C. Haustoria.
D. Meiosporium.
E. Mycelium.
F. Sporangium.
______2.
The feeding structure a fungus sends into plant cells is called
A. Apothecium.
B. Conidium.
C. Haustoria.
D. Meiosporium.
E. Mycelium.
F. Sporangium.
______3.
An asexual spore produced by certain types of fungi on the tips of special hyphae is
called
A. Apothecium.
B. Conidium.
C. Haustoria.
D. Meiosporium.
E. Mycelium.
F. Sporangium.
______4.
The overwintering structure of a fungus is called
A. Apothecium.
B. Conidium.
C. Haustorium.
D. Meiosporium.
E. Mycelium.
F. Sclerotium.
______5.
Most fungi reproduce primarily by
A. Asexual reproduction.
B. Formation of sclerotia.
C. Formation of spores.
D. Sexual reproduction.
E. Both a and c.
F. Both c and d.
______6.
We discussed four groups of true fungi last week. Which of the following is NOT
one of those groups?
A. Ascomycota.
B. Basidiomycota. **club and mushroom fungi
C. Chytridiomycota.
D. Protozomycota.
E. Zygomycota.
______7.
The first cases of Asian Soybean Rust in the United States were discovered in midNovember in Louisiana. According to an email I sent you last week, Asian Rust on
Soybean has also been confirmed in
A. Alabama.
B. California.
C. Mississippi.
D. Missouri.
E. Rhode Island.
F. Texas.
______8.
Most pathogenic fungi require the presence of
A. Water.
B. Temperatures above 75°F.
C. Zoospores.
D. Insect vectors.
E. Both a and b.
F. Both c and d.
______9.
While most fungi are spread by passive methods, some forcibly discharge their
spores into the environment. This method is known as
A. Maceration.
B. Oozing.
C. Puffing.
D. Sclerification.
E. Sneezing.
F. Sporotizing.
______10.
Identification of a plant pathogenic fungus is usually based on
A. Characteristics of reproductive structures.
B. Location on or in the host plant.
C. Method of dissemination.
D. Number of flagella.
E. Size and pattern of hyphae.
F. Type of Ti-plasmid it contains.
11.
For 1 bonus point, circle the fungal group in question 6 that is characterized as the club and
mushroom fungi.
I sent you an email containing a new article about research in California to control three diseases in a certain crop.
For 1 bonus point, name that crop. lettuce
AGH 483
Quiz 12
1 December 2004
(2.5 bonus points possible)
Multiple choice questions. Please read each question carefully then write the letter of the answer that best
completes the statement on the line in front of the question. Each question is worth 1 point.
______1.
According to an email I sent you this week, the soil-borne fungal disease that has
reappeared in San Joaquin cotton fields after decades of inactivity is
A. Asian stem rust.
B. Powdery mildew.
C. Verticillium wilt.
D. Xanthomonas rot.
______2.
Asian soybean rust has now been confirmed in four U.S. states. Those states are
Louisiana, Mississippi, Florida and
A. Arkansas.
B. Missouri.
C. Oklahoma.
D. Texas.
Short answer. Points possible vary and are indicated in parenthesis after the question or statement.
3. Guest speaker Dr. Wenping Qiu discussed three important plant viruses, each of which has
distinctive characteristics. The viruses are Tomato Spotted Wilt Virus (TSWV), Grape Leaf Roll
Associated Virus (GLRaV), and Tomato Bushy Stunt Virus (TBSV).
Name the three vectors of the viruses (0.5 points each), then circle the name of the virus that
has a narrow host range (0.5 points).
4. Since viruses are composed of proteins (the protein coat) and nucleic acids, laboratory detection
methods to confirm the cause of a plant viral disease are based on identification of 1) viral
proteins or of 2) nucleic acids isolated from plant specimens.
Circle the correct answer between the choices below these two paragraphs. 1 point each.
The enzyme-linked immunosorbent assay (ELISA) method involves the combination of
antibodies, antigens and a color-changing enzyme in a test container (well). ELISA is based on
detection of
Proteins.
Nucleic acids.
The Polymerase Chain Reaction (PCR) method involves the conversion of RNA into cDNA
(complementary DNA) and then the exponential replication of strands of the DNA. Once a
large amount of the DNA has been produced, is it placed at the top of a column containing a
gel. The DNA moves downward through the column based on its charge or particle size in a
process called electrophoresis. (It enables the separation of DNA molecules with just one
nucleotide difference in length in an electric field.) This results in a visible pattern of material
through the column, as seen in the illustration at left. Lab researchers have information on how
the pattern will look based on which virus the DNA was derived from. PCR is based on
detection of
Proteins.
Nucleic acids.
Replicase
p33
p92
CP
p41
p41
M
p2
P
p1
2
pX
gRNA
(4.8kb)
9
5. Study the above illustration of the genetic strand of RNA from the Tomato Bushy Stunted
Virus. Briefly explain the function of the following segments of the strand. (1 point each)
a. p33 and
p92
50
nm
b. p41
c. MP
6. Name the two plant species commonly used in labs for virus indexing. (Remember, these are
bio-index plants because they are susceptible to many viral strains and thus easily show
symptoms when researchers inoculate them with the virus.) (1 point each)
7. Name up to three systemic symptoms of viral infections. (0.5 points each)
AGH 483
8 December 2004
Quiz 13
Multiple choice Read each question carefully, then print the letter of the correct
answer on the line next to the question.
_______1.
This pathogen is responsible for late blight of potato.
a. Botrytis.
b. Phytophthora infestans
c. Pythium.
d. Vascular wilt.
_______2.
Fungus that is toxic to humans and animals.
a. Ergot.
b. Pythium.
c. Rust
d. Vascular wilt.
_______3.
Fusarium and verticillium are pathogens that cause this disease.
a. Botrytis.
b. Powdery mildew.
c. Pythium.
d. Vascular wilt.
_______4.
Which of the following statements about fungi is incorrect?
a. The filamentous body of a fungus is known as a mycelium.
b. Branches of mycelium are known as hyphae.
c. Growth of fungi occurs by fission.
d. Vegetative growth of fungi occurs at hyphae tips.
_______5.
Fungi usually require a moist environment except for which stage of
their life cycle?
a. Dissemination.
b. Germination.
c. Growth.
d. Reproduction.
e. All of the above.
_______6.
Identification of fungi is based on
a. Leaf spots and blights, fruiting bodies, spores or wilting.
b. Mycelium, leaf spots and blights, fruiting bodies or sporophores.
c. Mycelium, fruiting bodies, sclerotia, sporophores or spores.
d. Soft rots, scabs, leaf spots, overgrowths or cankers.
_______7.
Symptoms of this pathogen include damping off, with seeds or
seedlings dying or failing to thrive.
A. Botrytis.
B. Powdery mildew.
C. Pythium.
D.Vascular wilt.
_______8.
This pathogen is responsible for ergot.
A. Botrytis cineraria.
B. Claviceps purpurea.
C. Venturia inaequalis.
D.Xanthomonas ergotia.
_______9.
This is one of the most common diseases in greenhouses, with the
pathogen thriving in environments of high humidity and cool
temperatures.
A. Botrytis.
B. Powdery mildew.
C. Pythium.
D. Vascular wilt.
10. Name a method of disease prevention mentioned for the diseases in trees discussed last week
by guest lecturer Larry Ryan.
11. What is the name for a chemical produced by a fungus that is toxic to humans?