ICAR AICE-JRF/SRF Forest Pathology & Wood Decay: practice questions

1 · Nursery diseases: damping-off, leaf spots, blights · medium

Cylindrocladium (Calonectria) blight causes heavy losses especially in:

1. Mature sal forests during the dry season
2. Stored timber in depots
3. Alpine conifer forests in winter
4. Eucalyptus nurseries and mist chambers

2 · Nursery diseases: damping-off, leaf spots, blights · hard

Seedlings become resistant to damping-off mainly when:

1. Their stems become woody
2. They are given high nitrogen fertiliser daily
3. They are kept continuously wet and shaded
4. They are sown at very high density

3 · Root and butt rots · hard

Why are mixed-species stands less affected by some root rots?

1. Mixed stands contain no fungi of any kind in their soils
2. Root rots infect only mixed stands
3. Host-specific pathogens spread poorly between non-host trees
4. Mixed stands have no root contacts

4 · Wilts and cankers · medium

Chestnut blight, which nearly eliminated the American chestnut, is caused by:

1. Ophiostoma novo-ulmi
2. Hymenoscyphus fraxineus
3. Cryphonectria parasitica
4. Melampsora larici-populina

5 · Phytoplasma diseases (e.g. sandal spike) · easy

Phytoplasmas are insensitive to penicillin because they:

1. Live only in soil
2. Are fungi
3. Have very thick cell walls
4. Lack a cell wall

6 · Phytoplasma diseases (e.g. sandal spike) · hard

Phyllody, a phytoplasma symptom, means:

1. Premature fall of all the leaves in the hot summer months
2. Transformation of flower parts into leafy structures
3. Rotting of the phloem by fungi
4. Formation of root galls by nematodes

7 · Wood decay: white rot, brown rot, soft rot; discolouration and sapstain · medium

White rot fungi differ from brown rot fungi in that they:

1. Degrade only starch and sugars
2. Degrade lignin as well as cellulose
3. Attack only living leaves
4. Leave lignin and remove only bark

8 · Abiotic damage: frost, drought, pollution, wind · hard

Damage that appears uniformly across several unrelated species after a single event suggests:

1. A host-specific rust fungus
2. A phytoplasma spread by one vector species
3. An abiotic cause
4. A root rot spreading from a single stump

9 · Integrated disease management and forest health monitoring · hard

Therapy is rarely practical in forest disease management because:

1. Treating individual infected trees over large areas is too costly
2. Trees cannot be infected by pathogens once they pass sapling size
3. Therapy is forbidden by law in forests
4. All tree diseases cure themselves

10 · Invasive forest pathogens and plant health regulation · medium

Phytophthora ramorum is known for causing:

1. Teak leaf rust in Indian nurseries and young plantations
2. Sandal spike in Karnataka
3. Chestnut blight in Europe
4. Sudden oak death in California and larch mortality in Britain