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
  1. virus

  2. fungus

  3. bacterium

  4. copper deficiency

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

Dieback disease in citrus trees is a physiological disorder primarily caused by a deficiency of copper in the soil, which affects the tree's growth and health.

Multiple choice
  1. CO2

  2. SO2

  3. NO

  4. H2S

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

SO2 is poisonous and irritates the respiratory system of animals and humans. A continuous exposure to concentration of 0.2 ppm lasting for 3-4 days or even 0.5 ppm for full day has been reported to damage the lungs and increase the rate of mortality. In plants and grasses, SO2 also produces leaf injuries, called necrotic blotching. Sulphur dioxide damages barley, alfalfa, cotton and wheat.

Multiple choice
  1. mycobiont

  2. phycobiont

  3. isidia

  4. soridia

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

 Lichens are an intimate symbiosis, in which two species live together as a type of composite organism. Lichens are an obligate mutualism between a fungus mycobiont and an alga or blue-green bacterium phycobiont.

Multiple choice
  1. Chlorosis

  2. Rust Disease

  3. Blight disease

  4. None of the above

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

Rust disease in wheat is caused by fungi of the genus Puccinia, which appear as orange or brown pustules on the leaves and stems.

Multiple choice
  1. parasites

  2. chemoautotrophs

  3. decomposers

  4. symbionts

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

Lichens are composite organisms consisting of a symbiotic relationship between a fungus and an alga or cyanobacteria. The fungus provides structure and protection, while the alga provides food through photosynthesis.

Multiple choice
  1. bacteria

  2. virus

  3. mushroom

  4. poppy seeds

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

Psilocybin is a naturally occurring psychedelic compound produced by more than 200 species of fungi, commonly known as psilocybin mushrooms.

Multiple choice
  1. Colletotrichum

  2. Curvularia

  3. Epichloë

  4. Fusarium

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

Epichloë resides in only grasses. It colonises the shoot portion of grasses. It provides several benefits to the host, including the production of different herbivore-deterring alkaloids, increased stress resistance and growth promotion.

Multiple choice
  1. Arthrobotrys

  2. Gibberella

  3. Angulimaya

  4. Akanthomyces

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

Species of the hyphomycete genus (Arthrobotrys) produce constricting loops that quickly shut to grab nematodes or non-constricting loops or hyphal networks that entangle nematodes or sticky knobs that adhere to nematodes as they swim by.

Multiple choice
  1. Neutralism

  2. Mutualism

  3. Commensalism

  4. Parasitism

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

The relationship between Laccaria Bicolor and plants can be described as mutualism. Laccaria Bicolor shows an excess of enzymes used in ammonia uptake and a lack of enzymes that would be needed to degrade plant wall material. Thus, the fungus provides nitrogen and does not cause any harm to the trees in return for glucose, which it gets from photosynthetic plants.