Plant Diseases

Q.

Give examples of diseases that spread through air.

Q.

What are phytoalexins?

Q.

What are fungal diseases? Name any two fungal diseases.

Q.

What is the main wall composition in mycobacterium?

Q.

What kind of protozoan causes malaria?

Q. Yellowing of leaves due to lack of sunlight is called_____

Q.

Which of the following is a viral disease seen in plants?

1. Quick wilt

2. Blight disease

3. Bud Rot

4. Mosaic disease

Q.

Name of the disease that causes yellowing of leaves

1. necrosis

2. delayed flowering

3. chlorosis

4. die back of shoot

Q.

Name the disease caused by Plasmodium.

Q.

Identify the disease and the causative organism.

1. Quickwilt, Bacteria
   

2. Bunchy banana top, Virus

3. Quickwilt, Fungi
   

4. Bunchy banana top, Bacteria

Q.

What are carriers?

Q. Name any four plant diseases / human diseases caused by bacteria?

Q.

What are the long-chain fatty acids present in the wall of Mycobacterium called?

Q. Name any two plant diseases and the microbes that cause them.

Q. Which one of the following is a disease caused by zinc deficiency?

1. Khaira disease of rice
2. Black heart of potato
3. Die back of rice
4. Brown spot of rice

Q. Pusa Swarnim a variety of Brassica is resistant to

1. White rust
2. Curl and black rot
3. Bacterial blight
4. Mosaic virus.

Q.

How fatal are gram-negative bacteria?

Q. Which of the following is an example of viral disease?

1. Leaf curl of Papaya
2. Black rust of Wheat
3. Red rot of Sugarcane
4. Late blight of Potato

Q.

Differentiate between mold spores and pollen grains.

Q. On the basis of symptoms of chlorosis in leaves a student inferred that this was due to deficiency of nitrogen. This inference could be correct only if we assume that yellowing of leaves appeared first in.

1. Young leaves
2. Mature leaves followed by young leaves
3. Young leaves followed by mature leaves
4. Old leaves

Q.

If the older leaves of a plant shows yellowing and the yield is reduced, then it may be due to the deficiency of:

1. Potassium

2. Magnesium

3. Nitrogen

4. Phosphorus

Q. Consider the statements with respect to fungi :
(a) They show a great diversity in morphology and habitat.
(b) White spots seen on Mustard leaves are due to a saprophytic fungus.
(c) They prefer to grow in cold and humid places.
(d) The cell walls of fungi are composed of chitin and polysaccharides.
Of the above statements :

1. a and d are correct.
2. a and b are correct.
3. d and b are correct.
4. b and c are correct.
5. a and c are correct.

Q. Ustilago caused plant diseases are called smuts because

1. They parasitise cereals.
2. Mycelium is black.
3. They develop sooty masses of spores.
4. Affected parts become completely black.

Q. Ergot of rye causing organism

1. Has a coenocytic and aseptate mycelium
2. Is a sac fungus
3. It has cellulasic cell wall
4. Reproduce by motile asexual spores

Q.

Malaria is caused by ___ and spreads by ____.

Q. Extract of Tobacco with Mosaic disease was called contagium vivum fluidum by

1. Mayer
2. Ivanowski
3. Beijerink
4. Pasteur

Q. The toxic substance produced by the pathogen causing Brown leaf spot of rice, harming seedlings reducing respiration of the host is?

1. Piricularian
2. Cochliobolin
3. Ferulic acid
4. A-Picolinic acid

Q. Khaira is a plant disease caused due to the deficiency of

1. Zinc
2. Carbon
3. Iron
4. None of these

Q. Which of the following is a soil borne disease?

1. Red rot of sugar cane
2. Rust of wheat
3. Leaf spot of rice
4. Smut of bajra

Q. Irish Famine of 1845 was caused by

1. Alternaria solanii
2. Scelospora graminicola
3. Phytophthora infestans
4. Fusarium oxysporum