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

Which of the following pairs is not one of the fungal diseases, caused by pathogens in sugarcane?

  1. Yellow leaf spot - Cercosporidium kopkei

  2. Black stripe - Peronosclerospora sacchari

  3. Stem canker - Cytospora sacchari

  4. Red rot - Cercosporidium falcatum

  5. Brown leaf spot - Cercosporidium longipes
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Black stripe disease in sugarcane is caused by Cercospora atrofiliformis. Peronosclerospora sacchari fungus causes downy mildew disease in sugarcane.

Multiple choice

Match the fungal diseases in Group-I with causative pathogens in Group-II.

 
Group-I
Group-II
P. Leaf spot of cherries and palms 1. Claviceps purpurea
Q. Ergot of barley 2. Taphrina deformans
R. Citrus greasy leaf spot 3. Blueriella sp.
S. Leaf curl of peach and apricot 4. Drechslera teres
5. Mycosphaerella citri

  1. P - 3, Q - 1, R - 5, S - 2

  2. P - 5, Q - 1, R - 4, S - 2

  3. P - 3, Q - 4, R - 5, S - 2

  4. P - 2, Q - 3, R - 4, S - 1

  5. P - 1, Q - 4, R - 5, S - 3
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Leaf spot of cherries and palms is caused by Blueriella sp. The causative agent for ergot disease in barley is Claviceps purpurea. Citrus greasy leaf spot is caused by the fungus Mycosphaerella citri. Banana leaf spot is caused by Mycosphaerella musicosa. Taphrina deformans causes leaf curl of peach and apricot. Hence, the correct sequence of codes is P-3, Q-1, R-5, S-2.

Multiple choice

Match the diseases in List-A with causative fungal pathogens in List-B and select the correct answer using the codes given below.

List-A
List-B
A. Cottony snow mold of wheat 1. Sclerotium rolfsii
B. White leaf spot of crucifer 2. Coprinus psychromorbidus
C. Hull rot of almond 3. Rhizopus sp.
D. Southern blight of cotton 4. Pseudocercosporella capsellae

  1. A - 2, B - 4, C - 3, D - 1

  2. A - 3, B - 1, C - 4, D - 2

  3. A - 2, B - 4, C - 1, D - 3

  4. A - 1, B - 3, C - 2, D - 4

  5. A - 2, B - 1, C - 3, D - 4
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Cottony snow mold of wheat is caused by the fungus, Coprinus psychromorbidus. White leaf spot of crucifer is caused by Pseudocercosporella capsellae. Hull rot disease of almond is mainly caused by Rhizopus sp. Southern blight of cotton is caused by the fungal pathogen, Sclerotium rolfsii. Hence, the sequence of codes A-2, B-4, C-3, D-1 is correct.

Multiple choice

The fungal body is known as _______.

  1. holocarps

  2. eucarps

  3. mycelium

  4. mycorrhiza

  5. fruiting body
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Mycelium (plural mycelia) is the vegetative part of a fungus consisting of a mass of branching, thread-like hyphae.

Multiple choice

Place a moist bread near your window, you will observe small black round structures growing on it. What is that?

  1. The dust gets accumulated in the pores.

  2. Microorganisms

  3. The colour of flour changes due to exposure to atmosphere.

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

 Yes, it is correct. As microorganisms are present everywhere (in water, air, and soil). In fact, micro-organisms can survive under all types of environment. The black round structure seen growing when observed under microscope was found to be microorganisms.

Multiple choice

Which of the following is an example of a hydroxamate produced by fungi?

  1. Enterobactin

  2. Siderophores

  3. Ferrichrome

  4. Octahedral complex

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

It is a cyclic hexapeptide composed of three glycine and three modified ornithine residues that bind Fe (ІІІ) with hydroxamate groups. It has been produced by fungi of the genera Aspergillus, Ustilago, and Penicillium.