Plant infecting bacteria and fungi Flashcards
(21 cards)
1
Q
- prokaryotes
- single-celled
- 1-2um in size
- all plant surfaces have bacteria
outside = epiphytes
inside = endophytes
A
plant infecting bacteria
2
Q
structure of plant infection bacteria
A
- plasmid DNA
- ribosomes
- cell membranes
- capsule
- cell wall
- nucleoid
- flagellum
3
Q
symptoms of plant infections
A
- necrotic spots
- rots
- wilting
- galls
4
Q
wilting
A
- caused by high conc of bacteria in vascular tissue
- no water transport
5
Q
galls
A
- found on stem base
- alters hormonal regulation
6
Q
spread of plant infecting bacteria
A
- damage to plant enables entry
- vectors
- water
- wind and splash transmission
- seeds
7
Q
control measures for plant infecting bacteria
A
- prevent spread
- chemical control
- good crop hygiene
- competitionp
8
Q
- phloem limited bacteria
- 200-800nm in size
- lack cell walls
- obligate pathogens
- very small genome
A
phytoplasmas
9
Q
- eukaryotes
- heterotrophs from other organisms
- cause 70% of plant disease
A
fungi
10
Q
structure of fungi
A
- mycelium = the mat if branching tubular cells
- hyphae grow through and across tissues, absorbing nutrients
- fungal cell wall compromised of chitin and gluten
- hyphae can be separated by septa or can be aseptate
11
Q
fungi lifestyles
A
- biotrophic
- necrotrophic
12
Q
- don’t kill the plant, just feed on them
- access plant tissue using specialised structures = haustoria
- haustoria grows inside host tissue and enables the fungi to extract nutrients
- specialised within a narrow host range
A
biotrophic fungi
13
Q
- kill plant tissue w/ toxins/enzymes
- specialised or generalist w/ wide host range
A
necrotrophic fungi
14
Q
- one of most important disease causing groups
- includes phytophthora
- cell wall made of glucans not chitin
A
oomecytes
15
Q
fungi reproduction
A
- fungi can reproduce sexually or asexually
- range of diff spore types can be produced depending on life cycle
- can facilitate long and short distance spread
- can be resting structures enabling long term survival
16
Q
symptoms of fungal infection
A
- root rot
- vascular wilts
17
Q
monocyclic
A
- complete one lifecycle per year
18
Q
polycyclic
A
- completes several infection cycles per year
19
Q
integrates pest management
A
- uses multiple methods together
- fungicides
- biocontrol agents
- crop hygiene
- resistance breeding
20
Q
fungicides
A
- resistance is becoming a problem
- fewer new products being released and cost of discovering increasing
21
Q
biocontrol agents
A
- outcompete the pathogen
- kill pathogen
