Chapter Exam

Chapter 11: Agricultural Microbiology — Online MCQ Test

Q: Which of the following is a free-living nitrogen-fixing bacterium used as a biofertilizer?

Answer: B. Azotobacter — Azotobacter is a genus of free-living diazotrophic bacteria which are used as biofertilizers in agriculture.

Q: The symbiotic association between fungi and roots of higher plants is called:

Answer: A. Mycorrhiza — Mycorrhiza refers to the mutualistic symbiotic association between a fungus and the roots of a vascular plant.

Q: Rhizobium bacteria establish a symbiotic relationship specifically with plants of the family:

Answer: B. Fabaceae — Rhizobium bacteria form symbiotic root nodules in leguminous plants belonging to the family Fabaceae.

Q: A student isolates a bacterium that produces a toxin specific to Lepidopteran larvae. What is the most likely identity and application?

Answer: B. Bacillus thuringiensis; biopesticide — Bacillus thuringiensis produces specific Cry toxins that kill Lepidopteran larvae, making it a highly effective biopesticide.

MICROBIOLOGY · CLASS 11th · Tamil Nadu State Board

Practice Chapter 11: Agricultural Microbiology with a free chapter-wise online MCQ test for Tamil Nadu State Board CLASS 11th MICROBIOLOGY. This chapter covers: This chapter covers plant-microbe interactions plant disease etiology biocontrol agents and biopesticides. Students study Rhizobium Azotobacter biofertilizer applications and plant.... AI-generated questions from basic to board-exam level, with instant results and explanations.

Questions

20m

Time Limit

Attempts Left

10 random questions from this chapter (mixed difficulty)
Questions you've seen before won't repeat until the pool resets
You have 20 minutes — exam auto-submits when time is up
Maximum 3 attempts per chapter
Results and explanations shown immediately after submission

New here? Register free — includes 3 free chapter exams.

Chapter 11: Agricultural Microbiology — Important Questions & Answers (FAQ)

Frequently asked questions from Tamil Nadu State Board CLASS 11th MICROBIOLOGY — Chapter 11: Agricultural Microbiology, with answers and explanations. These are sample questions; the exam has its own separate question set.

Which of the following is a free-living nitrogen-fixing bacterium used as a biofertilizer?

A. Rhizobium
B. Azotobacter ✓
C. Agrobacterium
D. Bacillus subtilis

Answer: B. Azotobacter
Azotobacter is a genus of free-living diazotrophic bacteria which are used as biofertilizers in agriculture.

The symbiotic association between fungi and roots of higher plants is called:

A. Mycorrhiza ✓
B. Rhizosphere
C. Phyllosphere
D. Nodulation

Answer: A. Mycorrhiza
Mycorrhiza refers to the mutualistic symbiotic association between a fungus and the roots of a vascular plant.

Rhizobium bacteria establish a symbiotic relationship specifically with plants of the family:

A. Solanaceae
B. Fabaceae ✓
C. Poaceae
D. Brassicaceae

Answer: B. Fabaceae
Rhizobium bacteria form symbiotic root nodules in leguminous plants belonging to the family Fabaceae.

Why is the inoculation of leguminous crops with Rhizobium considered an environment-friendly practice?

A. It increases the need for chemical nitrogen fertilizers
B. It reduces the dependence on synthetic nitrogen fertilizers ✓
C. It eliminates the need for water entirely
D. It replaces the need for photosynthesis

Answer: B. It reduces the dependence on synthetic nitrogen fertilizers
Biological nitrogen fixation by Rhizobium reduces the need for energy-intensive synthetic fertilizers, lowering nitrogen runoff.

A student isolates a bacterium that produces a toxin specific to Lepidopteran larvae. What is the most likely identity and application?

A. Rhizobium; seed treatment
B. Bacillus thuringiensis; biopesticide ✓
C. Agrobacterium; plant growth promoter
D. Trichoderma; fungicide

Answer: B. Bacillus thuringiensis; biopesticide
Bacillus thuringiensis produces specific Cry toxins that kill Lepidopteran larvae, making it a highly effective biopesticide.

← Previous Chapter

Chapter 10: Soil Microbiology

Next Chapter →

Chapter 12: Medical Microbiology