Lecture 1 Flashcards
(21 cards)
Define Bacterium:
Unicellular microorganism that lacks defined organelles
Bacteria may have another copy of their single chromosome, the second copy is called a _______.
Plasmid
A singe-celled bacterium with rippled cell wall is called _________.
Xylella fastidiosa
What is Xylella fastidiosa?
A single-celled bacterium with rippled cell walls.
How do bacteria reproduce?
They reproduce by binary fission….cells divide into 2 exact copies.
What are some typical symptoms of bacterial pathogens?
- Infect through natural opening or would
- Angular borders
- Chlorotic halo
- Water soaked rot
- Tissue blight
- Rotten smell
What are some Bacterial Disease Management practices?
* Use disease free stock plants
- Choose disease resistant cultivars
- Create environmental conditions that do not favor disease
- Eradicate affected plant material
- Rotate Crops
- Copper containing fungicides
(EXCLUDE & ERADICATE!)
Management and Control practices for Bacterial Blight:
- Culture indexing
- Sterilize Propagating areas
- Use sterile planting materials
- Use disease-free stock plants
- Quarantine plants by source
- Eradicate affected plant material
(EXCLUSION AND ERADICATION!!!)
Branch Dieback is also called ______.
“sheperds crook”
Management and Control of Fire Blight:
- Spray copper fungicides
- Use resistant varieties
- Remove affected plant material
What is Phytoplasma?
A simpler form of bacteria that doesn’t have cell walls. They are vectored by leaf hoppers.
The diseases they cause are generally called “yellows”
Define Virus:
Ultramiucroscopic entity that contains genetic material within a protein coat that can only reproduce using the metabolic processes of a suitable host cell.
How does a virus reproduce?
Uses a host cell to make copies of itself.
Cannot reproduce without a host.
What are typical symptoms of viral pathogens?
What was one of the first viruses that we started to study?
Tobacco Mosaic Virus
What are the typical symptoms of viral pathogens:
- abnormal growth
- abnormal color
- look for the vector (what spreads the virus from plant to plant)
- Symptoms can take a while to show up or dont show up at all
What are the Vectors of a Virus?
- Primary vectors are insects with piercing, sucking mouthparts
- nematodes
- fungi
- mechanical
- infected plant parts
What are the Tospovirus Vectors?
- Western Flower Thrips
- Onion Thrips
Tospovirus Management…..
- Use disease free stock plants
- Eradicate thrips
- Eradicate affected plant material
- Eradicate weeeds and alternate hosts
- Quarantine plant material by source
Thrips Management…
- Monitor populations with sticky cards
- Use petunia as a trap crop
- Eradicate weeds and alternate hosts
- Exclude thrips from outside house
- Quarantine plant material by source
- Make application of labeled insecticide
What are the 3 types of parasitic plants?
- Epiphyte - Orchid, Spanish Moss
- Hemi parasite - Mistletoe
- True parasite - Dodder, Witchweed, Dwarf mistletoe
