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Flashcards in Basidiomycetes Deck (70)
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1
Q

Basidiomycetes, aka…

A

“club” fungi

2
Q

Basidium

A

Where basidiospores are produced

3
Q

Orders of Importance

A

Ustilaginales

Uredinales

4
Q

Ustilaginales

A
  • Smuts
  • Disease looks like soot
  • Two spore types:
    basidiospores (N)
    teliospores (N+N)
5
Q

Uredinales

A
  • Rusts

- Five spore types

6
Q

Smut Genera

A
  • Ustilago
  • Tilletia
  • Splacelotheca
7
Q

Characteristics of Smuts

A
  • worldwide
  • Conspicuous…
    Fungus replaces seed
    Produces black spores
    (Some attack stems / leaves)
  • Fastidious = fussy! hard to grow in culture
8
Q

Smut in seedlings

A

Attacks young tissue, entire seedling is colonized. As plant matures, fungus replaces embryo (flower) with spores… OW as teliospores in plant debris. Mgt - resistance, seed trt, systemic fungicides

ex. covered smut, bunt, head smut of corn

9
Q

Localized Smut

A

Attacks anywhere on plant

ex. common smut of corn

10
Q

Embryo Infection of Smut

A

Directly attacks embryo / flower… replaces embryo, then seed -> spores are produced. Seed infestation.

ex. louse smut

11
Q

Corn Smut causal organism

A

Common - Ustilago zeae

Head - Splacelotheca reilana

12
Q

Corn Smut host range

A

Corn and closest relatives

13
Q

Corn Smut geo

A

Wherever corn is grown

14
Q

Corn Smut symptoms

A

None!

15
Q

Corn Smut signs

A

Common - whitish / greyish galls or swelling anywhere on plant. Swellings darken, rupture… release black teliospores.

Head - kernels replaced with swellings. Swellings darken, rupture… release black teliospores.

Difference = where disease occurs initially

16
Q

Corn Smut disease cycle

A

Monocyclic

OW - teliospores (N+N) in debris (common), harvested seed (head)

Germinate -> basidiospores (N), wind-borne (common), infected seedling (head)

Infection - anywhere (common), grows with plant (head)

Signs … OW

17
Q

Corn Smut management

A

Not much to do.

Common - erratic, cannot predict.

Head - resistance, seed trt, actually a delicacy in some countries (truffle)

18
Q

Characteristics of Rusts

A
  • Among most destructive plant diseases… attack mostly leaves / stems.
  • Some need two unrelated hosts to complete life cycle (heteroecious), some need only one (autoecious)
  • Five spore forms in MACROCYCLIC life cycle:
    • teliospores
    • basidiospores
    • spermatia
    • aeciospores
    • urediniospores

MICROCYCLIC - missing one or more spore forms

19
Q

Rust signs

A

Yellowish, reddish spores

Black spores

20
Q

Rust symptoms

A

Orangish, yellowish spots usually on leaves

Galls

21
Q

Rust teliospores

A

(N+N), overwintering

22
Q

Rust basidiospores

A

(N), dispersed, produced in layers and exposed to air before shooting off

23
Q

Rust spermatia

A

Male gametes, only purpose is to fertilize

24
Q

Rust aeciospores

A

(N+N), result of sexual process (union of spermatia with receptive hyphae)

25
Q

Rust urediniospores

A

Repeating spores, dispersed

26
Q

Wheat stem rust

A

Puccinia graminis f. sp. tritici

Wheat and barberry (heteroecious)

  • urediniospore on wheat
  • teliospores
  • macrocyclic rust
27
Q

Cedar apple rust

A

Gymnosporangium juniperi-virginianae

Cedar and apple (heteroecious)

  • no urediniospores
  • microcyclic
28
Q

Coffee rust

A

Hemileia vastatrix

autoecious, polycyclic, microcyclic

  • urediniospores on coffee
  • basidiospores germinate
29
Q

White pine blister rust

A

Cronartium ribicola

Ribes (gooseberry, currants) as alt host
- urediniospores on ribes

30
Q

Fusiform gall rust on Southern pine

A

Cronartium quercuum f. sp. fusiforme

Oak is alt host

31
Q

Daylily rust

A

Puccinia hemerocallidis

32
Q

Asparagus rust

A

Puccinia asparagi

33
Q

Carnation rust

A

Uromyces dianthi

34
Q

Coffee Rust losses

A

Decreased vigor, longevity, photosynthetic capacity

This year’s disease affects next year’s losses

Severe infection -> twig / branch death

35
Q

Coffee Rust favorable conditions

A

59-82°F

wet conditions for spore germination, driven by rain more than wind

occurs continually due to year-round growth

36
Q

Coffee Rust management

A

Resistance

Quarantine (past)
- Sri Lanka, 1867… ~100 years until in Americas

Cultural practices

  • increase air flow
  • avoid excess water / nitrogen

Fungicides

37
Q

Soybean Rust

A

Asian - Phakospora pachyrhizi
- no resistance, watching for arrival in US

American - Phakospora meibromiae
- not as destructive

Must blow into soybean crop to infect (takes weeks or months) -> hits around maturity

38
Q

Exobasidiales

A

No basidiocarp, basidiospores produced on surface of parasitized tissue

Exobasidium causes leaf galls of azalea / camelia

39
Q

Ceratobasidiales

A

Weblike basidiocarp, inconspicuous, “sterile” fungi (no spores)

40
Q

Thanatephorus

A

Rhizoctonia spp. - root rots

41
Q

Rhizoctonia root rot / Large Patch of Turf causal organism

A

Rhizoctonia solani and other species

42
Q

Rhizoctonia root rot / Large Patch of Turf host

A

most plants of interest to man, esp herbaceous annuals (cotton, soybean, lettuce, tomato)

all warm season turfgrasses

43
Q

Rhizoctonia root rot / Large Patch of Turf geo

A

worldwide

44
Q

Rhizoctonia root rot / Large Patch of Turf symptoms

A

Turf - circular patches of affected plants develop during spring / fall when grasses enter /exit dormancy period. Recently affected foliage may appear orange. Water-soaked or reddish brown lesions found on leaf sheaths (foliage dies back from this point)

Other plants - reddish-brown, sunken lesions

45
Q

Rhizoctonia root rot / Large Patch of Turf signs

A

in wet weather, white cobwebby fungal growth, likely found on lower parts of plant

Distinguishable by right-angle branching

46
Q

Rhizoctonia root rot / Large Patch of Turf favorable conditions

A

48 hours continuous moisture

Thatch temps between 50 - 70° F

47
Q

Rhizoctonia root rot / Large Patch of Turf management

A

Control moisture -> soil drainage, air circulation, reduce excess shade

Mowing height (turf) -> with zoyziagrass, 1.5 inches decreases disease compared to 0.5 inch

48
Q

Thyphula

A

Snow molds of turfgrasses

49
Q

Agaricomycotina

A

characterized for having spores on lining of surfaces of small tubes or pores

50
Q

Southern Stem Blight / white mold causal organism

A

Aethalium (Sclerotium) rolfsii

51
Q

Sclerotium (-tia)

A

survival structure of Aethalium (Sclerotium) rolfsii [Southern Stem Blight / white mold]

golden to dark brown / black as they develop

52
Q

Southern Stem Blight / white mold host range

A

more than 500 plant species

  • tomato
  • peanut
  • apple
  • many woody ornamentals and herbaceous annuals
53
Q

Southern Stem Blight / white mold geo

A

Worldwide, but predominant in warmer climates

54
Q

Southern Stem Blight / white mold symptoms

A

Begins as water-soaked lesion near soil line

Lesions expand to girdle stem

Plants wilt and die rapidly

55
Q

Southern Stem Blight / white mold signs

A

White mat of mycelium develops at lesion… spreads across soil surface.

Round mycelial bodies begin to form

Seed-size structures are sclerotia -> darken to near black

56
Q

Southern Stem Blight / white mold favorable conditions

A

Monocyclic

wide temp range (46 - 104° F), optimal = 81 - 95° F, high humidity favors hyphal growth

fluctuating moisture promotes sclerotial germination and rapid plant death, more sclerotia produced in 5 - 7 days

DOES NOT HAVE SPORES - mammals spread this disease. Will spread through soil but not far

57
Q

Southern Stem Blight / white mold management

A

Keep fungus out of production area

Crop rotation to non-host (ie. grass)

Prompt removal of infected plants

Soil solarization - clear plastic, direct sun, 4 - 8 weeks

Fungicide (must be at base of plant)

58
Q

Heterobasidion annosus (Fomes annosum)

A

Root and butt rot of conifers

59
Q

Rotting fungi

A

Characterized by spores borne radiating gills, lots of mycorrhizal fungi

60
Q

Armillaria mellea

A

Root rot of forest and fruit trees, esp oak.

Has edible fruiting body

61
Q

Pleurotus spp

A

white rots of hardwoods

62
Q

Pholiota spp

A

brown rots of hardwoods

63
Q

Agaricus bisporus

A

Common edible mushroom in grocery store

64
Q

Conks

A

“mushroom-like” structure on trees and woody structures. Monocyclic

basidiospores INSIDE conks… fall from structures, picked up by wind. Enters through wounds on trees / host.

Kills trees due to inner rotting

65
Q

Mushrooms

A

Basidiospores on gills

Create fairy rings - usually presence of tree stump / wood in soil or old, buried roots

66
Q

Dry rots

A

break down cellulose

67
Q

Wet rots

A

Whitish fungal growth

fungi draw water to them

68
Q

Stain fungi

A

Discolors wood - pink, blue, green, orange

69
Q

Mycorrhizae

A

Root infectors, beneficial - helps plants absorb minerals (increase root surface area)

70
Q

Three types of mycorrhizae

A

Ectomycorrhizae - external to root

Endomycorrhizae - internal to root

Ericoid mycorrhizae - intermediate