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

Which of the following fungi cause brain tumor?

In our daily routine, fungi have both positive and negative impacts. There are number of beneficial roles of fungi in different aspects of our life such as food, scientific uses, medicines, agriculture, commercial products, etc.

  1. Amanita

  2. Alternaria solani

  3. Albugo candida

  4. Cryptococcus neoformans

  5. Pucvinia graministice
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Cryptococcus neoformans causes different human diseases such as meningitis and brain tumor which is encapsulated yeast, susceptible both within plants’ animals’ body. Sometimes it may found in excrement of pigeon.

Multiple choice

Which of the following causes destruction of domestic objects like wooden furniture and leather bags?

Economic importance of bacteria also includes its harmful activities. Around 90% infections in humans are caused by bacteria. They equally affect green plants including their different parts.

  1. Staphylococcus aureus

  2. Sporophytic bacteria

  3. Spirochaete cytophaga

  4. Mycobacterium leprae

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

It causes destruction of different domestic objects. It is chemoheterotrophic in nature. It causes some other diseases like leptospirosis, Lyme disorder and syphilis.

Multiple choice

Which of the following bacteria causes leaf blight of rice?

Economic importance of bacteria also includes its harmful activities. Around 90% infections in humans are caused by bacteria. They equally affect green plants including their different parts.

  1. Xanthomonas citri

  2. Xanthomonas oryzae

  3. Salmonella

  4. Saprophytic bacterium

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

Xanthomonas oryzae, species of proteobacteria is responsible for causing leaf blight of rice. Rice is its important host.

Multiple choice

Match the following items: Column-I Column-II

  1. Helminthosporium oryzae A. Early blight of potato
  2. Puccinia graminis B. Late blight diseases
  3. Alternaria solani C. Stem rot diseases
  4. Phytiphtoria infestans D. Brown rust
  5. Macrophomina phaseoli E. Black rust

  1. 1 - A, 2 - B, 3 - C, 4 - D, 5 - E

  2. 1 - E, 2 - A, 3 - C, 4 - D, 5 - B

  3. 1 - D, 2 - E, 3 - A, 4 - B, 5 - C

  4. 1 - B, 2 - C, 3 - D, 4 - A, 5 - E

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

Helminthosporium oryzae is a fungus causes brown rust. All species of Puccinia graminis obligate plant pathogen and causes black rust. Alternaria solani is a harmful fungus causes early blight of potato. Phytiphtoria infestans is an oomycete which causes late blight diseases. Macrophomina phaseoli botryosphaeriaceae fungus causes Stem rot diseases

Multiple choice

Plasma membrane of prokaryotes is less rigid because it is devoid of

  1. membrane proteins

  2. sterols like cholesterol

  3. phospholipids

  4. lipids

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

The plasma membrane of a bacterial cell is less rigid as it is devoid of sterols like cholesterol. One exception to this is the prokaryote mycoplasma that contains sterols in the plasma membrane. In the absence of cell wall, sterol containing plasma membrane offers strength and rigidity to this prokaryote.

Multiple choice

Which of the following statements is true for the prokaryotes?

  1. Prokaryotes lack peptidoglycan in their cell wall.

  2. Prokaryotes lack plasma membranes.

  3. Prokaryotes lack histones proteins.

  4. Prokaryotes lack ribosomes.

  5. Prokaryotes lack photosynthesis.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Histone proteins are associated with the DNA of eukaryotes, but not with the DNA of prokaryotes as they lack histone proteins.

Multiple choice

Which of the following food crop diseases are caused by a virus?

  1. Citrus canker and rice stripe necrosis

  2. Cassava mosaic disease and rice stripe necrosis

  3. Potato late blight and citrus canker

  4. Rice stripe necrosis and potato late blight

  5. Potato late blight and cassava mosaic disease
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Cassava mosaic disease is caused by Begomovirus. Rice stripe necrosis rice is caused by stripe necrosis virus rice.