Apply Now Student Hub Feedback
Science and Technology question from UPSC CSE-Prelims, 2013

Consider the following organisms:

1. Agaricus
2. Nostoc
3. Spirogyra 

Which of the above is/are used as biofertilizer/biofertilizers? 

Last updated Oct 10, 2026
Correct Answer: Option B — 2 only
• Correct Answer: (b) 2 only
• Explanation: Nostoc is a cyanobacterium capable of fixing atmospheric nitrogen. Agaricus is a mushroom (fungus), and Spirogyra is a green algae; neither is used as a biofertilizer.
Answer verified by Quintessence Classes faculty — Karan Nagar, Srinagar.
Try another question from UPSC CSE 2013 Prelims Try another question from Science and Technology

About this question

UPSC CSE 2013 Prelims

Details

Exam UPSC CSE
Stage Prelims
Year 2013
Subject Science and Technology
View all questions from this paper

More Science and Technology questions

From across UPSC, JKPSC, and JKSSB papers — same subject, different years.

Launched on 25th December, 2021, James Webb Space Telescope has been much news since then. What are its unique features which make it sup... UPSC CSE 2023 Mains · Science and Technology What is an FRP composite material? How are they manufactured? Discuss their application in the aviation and automobile industries. UPSC CSE 2013 Mains · Science and Technology What is allelopathy? Discuss its role in major cropping systems of irrigated agriculture. UPSC CSE 2016 Mains · Science and Technology Which of the following statements is/are correct?1. Viruses lack enzymes necessary for the generation of energy. 2. Viruses can be cultur... UPSC CSE 2013 Prelims · Science and Technology What are the research and developmental achievements in applied biotechnology? How will these achievements help to uplift the poorer sect... UPSC CSE 2021 Mains · Science and Technology

Practice 2,683+ more PYQs interactively

Filter by subject, year, and exam in real time. Get instant feedback, detailed explanations, and track your progress.

Open practice portal