Ascomycetes

Question 1

acomycetes

Answer 1

sac fungi; sexual spores produced in specialized stucture called ascus; ascopores are in groups of 8; true, septate mycelium

Question 2

naked asci

Answer 2

no ascus; ascospores produced on mycelium

Question 3

Naked asci order?

Answer 3

Taphrinales

Question 4

Taphrina sp causes?

Answer 4

leaf curls and blisters

Question 5

cleistothecium

Answer 5

completely closed ascus

Question 6

Cleistothecium order?

Answer 6

Erysiphales

Question 7

What is the order of the Powdery Mildews?

Answer 7

Erysiphales

Question 8

What relative humidity is needed for a powdery mildew to infect?

Answer 8

85%

Question 9

What is the common management for powdery mildew?

Answer 9

Resistance, environment changes, spay (even with water - the conidia are hydrophobic)

Question 10

Erisiphe lagerstromiae

Answer 10

Powdery mildew of crepe myrtle

Question 11

causal organism of Peach leaf curl?

Answer 11

Taphrina deformans (no asci)

Question 12

Symptoms of peach leaf curl?

Answer 12

deformation; warts on fruit; purplish, reddish discoloration on affected areas

Question 13

signs of peach leaf curl?

Answer 13

naked asci with ascospores; affected areas appear dusty

Question 14

disease cycle of peach leaf curl?

Answer 14

fungus survives in bark crevices or in buds - buds swell and fungus invades young tissue - syptoms - signs - repeat or ow

Question 15

favorable conditions of peach leaf curl?

Answer 15

50-70 for infection; older leaves cannot be invaded; rain washes ascospores into new tissue

Question 16

management of peach leaf curl?

Answer 16

maintain tree vigor, proper fruit thinning, , reduced moisture stress, appropriate N Fertility, single well timed fungicide application

Question 17

causal organism of powdery mildew of wheat?

Answer 17

Erysiphe graminis f.sp. tritici (cliestothecium)

Question 18

symptoms of powdery mildew of wheat?

Answer 18

initially see chlorotic spots in lower canopy

Question 19

signs of powdery mildew of wheat?

Answer 19

white mycelial growth on any photosynthetic tissue; on wheat in distinct little piles; late season, cleistothecia develop

Question 20

disease cycle of powdery mildew of wheat?

Answer 20

survival in cleistothecia - release ascospores - infect - signs, mycelium and conidia - infect and repeat or return to survival stage in late season

Question 21

favorable conditions of powdery mildew of wheat?

Answer 21

temp fluctuations 55 to 75 to make cliestothecia crack. spring and fall. >85 for reproduction, >95 for infection.

Question 22

losses from powdery mildew of wheat?

Answer 22

weakened plants, fewer tillers and florets, less grain fill

Question 23

management of powdery mildew of wheat?

Answer 23

resistance! increase circulation, fungicide

Question 24

causal organism of melding out of turf?

Answer 24

Bipolaris sorokiniana

Question 25

geographical distribution of melding out of turf?

Answer 25

wherever turf is valued. US UK Japan Australia

Question 26

Symptoms of melding out of turf?

Answer 26

initial water soaked darkened spots, yellow halo around spots. become necrotic, enlarge, can girdle leaf, leaf dies. older leaves more susceptible

Question 27

signs of melding out of turf?

Answer 27

conidia on leaf surface.

Question 28

disease cycle of melding out of turf?

Answer 28

survive on host or in debris - conidia always present, invade spring new growth w/ wet conditions - symptoms and repeat or asexual spore

Question 29

favorable conditions of melding out of turf?

Answer 29

~60 F for most rapid infection, extended moisture, high humidity, stress`

Question 30

management of melding out of turf?

Answer 30

eliminate stress