Plant viruses Flashcards
(8 cards)
1
Q
structure of plant viruses
A
- infectious agents
- RNA/DNA genomes enclosed in a protective coat
- DNA codes for proteins necessary for replication
- host cell may (not) be destroyed in process of replication and release
2
Q
viroids
A
- smallest known pathogens
- 30+ viroids characterised
- single-stranded RNA pathogens - no proteins
- highly stable (unlike RNA) due to complex structure
3
Q
leaf level symptoms
A
- chlorosis
- mosaic
- necrosis
4
Q
chlorosis
A
- yellowing of leaves
- also caused by nutrient deficiency
5
Q
mosaic
A
- light and dark patches on leaves
6
Q
necrosis
A
- veins die
- leads to yellowing, the die
7
Q
whole plant level fungus symptoms
A
- dwarfing and stunting
- leaf curl chlorosis
- marbling
8
Q
three-way mutualistic symbiosis
A
- infected by both virus & bacteria
- has made plant more
1) temperature tolerant
2) drought tolerant
