Biology

Microbes and Plant Diseases

1,145 Questions

Microbes and plant diseases examine the role of fungi, bacteria, and viruses in causing infections in plants and humans. Topics cover symbiotic associations like mycorrhiza, fungal structures, and specific agricultural pathogens. Practice these biology questions to master microbiology concepts for upcoming competitive examinations.

Fungal associationsPlant pathogensMicrobial structuresBacterial infections

Microbes and Plant Diseases Questions

Multiple choice

Wildfire of tobacco is caused by

  1. Agrobacterium rhizogenes

  2. Erwinia carotovora

  3. Pseudomonas syringae

  4. Ralstonia solanacearum

  5. Rhodococcus fascians
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Wildfire of tobacco is caused by Pseudomonas syringae, a rod-shaped, Gram-negative bacterium with polar flagella. Symptoms of wildfire of tobacco include yellowish green spots on leaves. It causes losses in seedlings and field plants and occurs worldwide.

Multiple choice

Which of the following diseases is related to banana?

  1. Rust

  2. Tikka

  3. Wilt

  4. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Panama disease (Fusarium wilt) is a serious fungal disease affecting banana plants, caused by the soil-borne fungus Fusarium oxysporum. It attacks the vascular system, blocking water transport and causing wilting and plant death. Rust affects wheat and other cereals, tikka is a groundnut disease, and neither are specific to bananas.

Multiple choice

Berkeley bodies are found in

  1. Candida utilis

  2. Kluyveromyces lactis

  3. Aspergillus niger

  4. Saccharomyces cerevisiae

  5. Penicillium chrysogenum
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This option is correct because Saccharomyces cerevisiae is currently the only yeast cell that is known to have Berkeley bodies present.

Multiple choice

Ringworm disease is caused by

  1. tapeworm

  2. earthworm

  3. fungi

  4. bacteria
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Ringworm (tinea) is a fungal infection caused by dermatophytes, which are a type of fungi that grow on skin, hair, and nails. Despite its name suggesting a worm, it has no relation to actual worms like tapeworms or earthworms. Bacteria cause different types of infections altogether.

Multiple choice

Consider the following diseases of plants:

  1. Root knot of sugar-cane.
  2. Root rot of wheat.
  3. Wilt of cotton.
  4. Angular leaf spot of cotton. Which of these diseases is/are caused by fungi?

  1. 1 and 4 only

  2. 2 only

  3. 2 and 3

  4. 1,3 and 4

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Root knot of sugar-cane (Meloidogyne) and wilt of cotton (Verticillium/Fusarium) are caused by nematodes, not fungi. Angular leaf spot of cotton (Xanthomonas) is bacterial. Only root rot of wheat is fungal (Gaeumannomyces/other fungi). Therefore, 1, 3, and 4 are not caused by fungi.

Multiple choice

Which microbe helps in the baking industry?

  1. Virus

  2. Yeast

  3. Protozoan

  4. Helminth worm

  5. Streptococcus
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Saccharomyces cerevisiae or yeast is extensively used in the baking industry to make the dough rise by fermentation.