Rose Rust

Question 1

Rose Rust

Symptoms - check both side of leaves

Answer 1

Autoecious - does not require alternate host.
Five different spore types - vary with season as do symptoms.
Spring - infections usually only seen on species roses as rupturing the stem and bright orange spores which rupture from within stem.
Early summer - orange speckling of foliage with bright orange spore masses underneath and possible leaf drop.
Late summer - Black pustules develop on underside of leaf and defoliation is inevitable.
Autumn - leaf fall

Question 2

Rose Rust - description of cause.

Answer 2

Fungal spores, spreads by wind. Spores can survive over the winter on soil surface and in leaf debris, also on surfaces such as plant supports.
Biotroph - infects host tissue for a long time without killing them.
Gains nutrition from the living cells.
Phragmidium tuberculatem only affect roses and pass winters as resting spores.

Question 3

1.
Disease cycle of rose rust
Name of fungal cause

Answer 3

Phragmidium

Question 4

2. Rose rust life cycle

…. germinate in spring to produce …..

Answer 4

Teliospores germinate in spring to produce basidia.

Question 5

3.
Rose rust life cycle

…. produce ….. which infect young foliage.

Answer 5

Basidia produce basidiospores which infect young foliage.

Question 6

4.
Rose rust life cycle

….develop and …. form, these bear ….

Answer 6

Orange/yellow leaf spots develop and spermagonia form, these bear male spermatia and female hyphae.

Question 7

5.
Rose rust life cycle

…. transported to receptive … by insects attracted by ……..from ….. . ……takes place.

Answer 7

Spermatia transported to receptive hyphae by insects attracted by sugary exudate from spermatia. Fertilisation takes place.

Question 8

6.
Life cycle of rose rust

… formed on underside of leaf and release ….

Answer 8

Aecia formed on underside of leaf and release aeciospores.

Question 9

7.
Life cycle of rose rust

…. infect new tissue.

Answer 9

Aeciospores infect new tissue.

Question 10

8.
Rose rust life cycle

…. form. …. appear as ……. in summer.

Answer 10

Uredinia form. Uredinia appear as orange pustules in summer.

Question 11

9.
Rose rust life cycle

… spread the fungus in the host

Answer 11

Urediniospores spread the fungus in the host.

Question 12

10.
Rose rust life cycle

….. germinate to produce …. in the following spring.

Answer 12

Teliospores germinate to produce basidum in the following spring.

Question 13

11. Rose rust life cycle

….. are produced from a …. in autumn.

Answer 13

Teliospores are produced from a telium in autumn.