Biology

Microbes and Plant Diseases

1,118 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

Rapid spreading of bread mould on slices of bread is due to

  1. formation of round shaped sporangia.

  2. absence of spores in air.

  3. presence of large number of thread like branched hyphae.

  4. absence of moisture and nutrients.

  5. presence of moisture and nutrients.
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

This is the correct option.

Multiple choice

In lichens, the mycobiont is made up of

  1. phycomycetes

  2. ascomycetes

  3. ascomycetes, basidiomycetes and deuteromycetes

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

The fungal component (mycobiont) of most lichens belongs to the Ascomycetes, though some lichens involve Basidiomycetes or Deuteromycetes.

Multiple choice

Which of the following fungi is poisonous?

  1. Armillaria

  2. Blastomyces

  3. Microsporum

  4. Amanita
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Amanita is a genus of fungi that includes several highly poisonous species, such as the Death Cap (Amanita phalloides).

Multiple choice

Which organism causes the powdery mildew of cereals?

  1. Erysiphe polygoni

  2. Sclerotinia fruticola

  3. Uncinula necator

  4. Erysiphe graminicola
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Erysiphe graminis (often referred to as Erysiphe graminicola in some older texts) is the fungus responsible for powdery mildew of cereals.

Multiple choice

Pythium debaryanum causes

  1. downy mildew of grapes

  2. downy mildew of peas

  3. damping off of the seedling

  4. wart disease of potato
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Pythium debaryanum is a well-known soil-borne pathogen that causes 'damping off' disease in seedlings.

Multiple choice

Universal veil is observed in

  1. basidiocarp of agaricus

  2. basidiocarp of of amanita

  3. both (1) and (2)

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

A universal veil is a membrane that encloses the entire developing fruit body of certain mushrooms, such as those in the genus Amanita.

Multiple choice

Stipe and pileus are found in

  1. basidiocarp of agaricus

  2. albugo

  3. phytophthora

  4. pythium
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Agaricus (the common mushroom) has a distinct basidiocarp consisting of a pileus (cap) supported by a stipe (stalk).

Multiple choice

Which of the following is mismatched?

  1. Zoospores-Albugo

  2. Conidium-Phytophthora

  3. Chlamydospore-Synchytrium

  4. Aplanospore-Mucor
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Chlamydospores are thick-walled resting spores. Synchytrium typically produces resting sporangia, not chlamydospores, making this the mismatched pair.

Multiple choice

Basidiomycetes showing bioluminescence is

  1. pleurotus

  2. amanita

  3. psilocybe

  4. all of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Pleurotus is a well-known genus of mushrooms that includes species capable of bioluminescence. While other fungi may exhibit this trait, Pleurotus is the primary example among the choices provided.

Multiple choice

In helotism,

  1. there is controlled parasitism

  2. the fungal component present in lichen shows complete parasitism

  3. the phenomenon of commensalism is shown

  4. none of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Helotism refers to the relationship in lichens where the fungus acts as a master and the alga as a slave, which is essentially a form of controlled parasitism. The fungus benefits at the expense of the alga, though it is often described as a mutualistic symbiosis.

Multiple choice

Which of the following matches of crop disease: causative agent is not correct?

  1. Powdery mildew of cucurbits: Blumeria graminis

  2. Black rot of crucifers: Xanthomonas campestris

  3. Downy mildew of rice: Sclerophthora macrospora

  4. Red rot disease of sugarcane: Colletotrichum falcatum

  5. Fire blight of pome fruits: Erwinia amylovora
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Powdery mildew of cucurbits is caused by two fungus: Sphaerotheca fuliginea and Erysiphe cichoracearum. Blumeria graminis causes powdery mildew of wheat.