12/1/2014
PlantPathologyLab
Viruses
Week6Review:Bacteria
Methods of identification for bacteria including:
Observation of Bacterial Signs
Gram Staining
Culture (Koch’s Postulates)
Motility (Hanging Drop Demo)
Biochemical Test
Hypersensitive Response
1
12/1/2014
Week6Review:Bacteria
Agrobacterium tumefaciens
causes crown gall
Agrobacterium radiobacter K84+ produces agrocin which inhibits growth of closely related species (i.e. A. tumefaciens)
ThisWeekinLab:
Viruses
Page 73‐80
Continuing Koch’s Postulates
Page 17‐19
Bacteria‐ HR Results
Page 67
Wheat Stipe Rust Results
Page 123
2
12/1/2014
Virus
Viruses
Typical symptoms include:
Chlorotic mosaics
Clearing of veins
Leaf curl
Stunting of plant growth
3
12/1/2014
Viruses:pg 75‐82
Observe diseased plants and demos
Complete 3 experimental set‐ups
Mechanically inoculate indicator plants
Test for virus in plant tissue with an immunostrip‐ELISA
Viruses:pg 75‐82
Mechanically inoculate indicator plants
1 plant per group; 2 types of tobacco, or aphids
Carborundum powder will create an entry point for the virus
Inoculate with plant extract
Both tobacco plants get TEV and TMV
VIDEO DEMO
https://www.youtube.com/watch?v=c15x
mnYi8cQ&feature=youtu.be
4
12/1/2014
Viruses:pg 75‐82
This week, you’ll be labeling plants. Every time you perform an experiment on a plant, be sure to include:
Name of Group Members
Time
Treatment
Room # (3077)
VirusIdentificationMethods
1.
2.
3.
4.
Pathogenicity (Bioassay using indicator hosts)
Transmissibility (Vector transmission assay)
Architecture of the virus particle (Electron microscopy)
Properties of the viral protein coat (ELISA Test, utilizing antibodies) 5. Characterization of viral nucleic acid (PCR)
5
12/1/2014
Enzyme Linked Immunosorbent Assay
ELISAteststripvideo
http://www.whfreeman.com/catalog/static/whf/kuby/content/anm/kb07an01.htm
6
12/1/2014
Koch’sPostulates:pg 17‐19
1. Consistent association between pathogen and host symptoms
2. Isolate the suspected pathogen from the diseased plant
3. Inoculate the isolated organism onto a healthy plant to see if the symptoms are reproduced
4. Re‐culture the pathogen and determine that it is the same as the original isolate
Koch’sPostulates:pg 17‐19
Work in groups of 2 or 3 : 1 potato
Locate colonies that have sunken into media
Touch one colony with toothpick and then puncture potato
Wrap potato in moist paper towel and then in plastic wrap
Try a control also
Toothpick + water
7
12/1/2014
Bacteria:pg 67
Record HR results on tobacco plants
WheatStripeRust:pg 123
Record reaction of host differentials
8
12/1/2014
Pot color
Blue
Green
Red
Orange
Cultivar
Tyee
Tres
True Faro
Jacmar
VirusVideo
https://media.oregonstate.edu/media/0_bph8up9q
9
12/1/2014
Inlabtoday:
Viruses
Page 73‐80
Continuing Koch’s Postulates
Page 17‐19
Bacteria‐ HR Results
Page 67
Wheat Stipe Rust Results
Page 109
Disease of the week #2 and extra credit due
MARK WHICH D.O.W. IS EXTRA CREDIT!!!!!
10