Chapter 16 Flashcards
Management of plant disease depends on whether the disease is biotic or abiotic.
True
The life cycle of a fungus can involve only one type of spore.
False
Mycelium is a symptom of fungal disease.
True
Scab is more likely to be a problem in dry, cool areas.
False
Smut can overwinter in soil, plant debris, and seed.
True
Most fungal agents that cause postharvest diseases are introduced to the affected seed after harvest.
False
Bacterial wilt of alfalfa is less an issue today because resistant varieties.
True
Plant pathogenic viruses are generally composed of DNA enclosed in a protein case.
False
Viruses can enter the plant through the stomata.
False
Fungi can transmit viruses to a plant.
True
A method to control viral diseases is the use of pesticides.
False
Insects that damage plants all have mouthparts that pierce.
False
Many bactericides are copper-based.
True
Contact insecticides, once absorbed by the insect, attack the nervous and respiratory system.
True
UG99 stem rust has the potential to threaten 20% of the world’s food supply.
True
The visual response by the plant to the pathogen is”
A. a symptom
B. a disease
C. an injury
D. an infection
A. a symptom
Which of the following is NOT an abiotic disease factor?
A. parasitic plant
B. water deprivation
C. soil acidity
D. herbicide
A. parasitic plant
Which of the following organisms reproduces by spores?
A. bacterium
B. virus
C. fungus
D. nematode
C. fungus
Rust diseases are caused by which group of fungi?
A. sclertinomycetes
B. basidiomycetes
C. fusariomycetes
D. pythiomycetes
B. basidiomycetes
Stem rust can have up to how many different spore stages?
A. two
B. three
C. five
D. seven
C. five
Damping off affects which growth stage?
A. seedling
B. flowering
C. fruiting
D. senescence
A. seedling
The disease associated with the Salem witch trials is
A. scab
B. rust
C. blast
D. ergot
D. ergot
Leaf spots due to bacteria tend to be:
A. round
B. angular
C. mosaic
D. linear
B. angular
Bacterial wilts occur when the bacteria invade the:
A. flowers
B. leaves
C. fruit
D. vascular system
D. vascular system
Common and halo blight affect which crop species?
A. corn
B. small grains
C. sugar beets
D. beans
D. beans
Vein clearing is a symptom common in:
A. viral diseases
B. bacterial diseases
C. plant parasitic diseases
D. fungal diseases
A. viral diseases
Which plant family does tobacco mosaic virus primarily infect?
A. rose family
B. potato family
C. grass family
D. legume family
B. potato family
Aster yellows is caused by which group of organisms?
A. fungi
B. bacteria
C. viruses
D. mycoplasma-like organisms
D. mycoplasma-like organisms
Nematodes are a type of:
A. insect
B. roundworm
C. fungi
D. bacteria
B. roundworm
The best strategy for nematode control would be:
A. removal of plant debris
B. seed treatments
C. fungicides
D. crop rotation
D. crop rotation
The soybean cyst nematode causes damage by:
A. necrosis
B. clogging phloem
C. feeding on roots
D. defoliating leaves
C. feeding on roots
The corn earworm feeds on what part of the corn?
A. roots
B. blades
C. stems
D. kernels
D. kernels
A potential biocontrol being evaluated for use on soybean aphid is which of the following?
A. Bacillus thuringiensis
B. Binodoxys communis
C. Pyrausta nubilalis
D. Leptinotarsa decimilneata
B. Binodoxys communis
