Question

Which of the following Scientist are associated with the development of humus?
(A). Kononova
(B). Waksman
(C). Stevenson
(D). Beijerinck
Choose the correct answer from the options given below:

• A. (A), (B) and (C) only.
• B. (A), (B) and (D) only.
• C. (A), (C) and (D) only.
• D. (B), (C) and (D) only.

Hint:

Waksman (who co-discovered streptomycin) wrote the definitive early book on "Humus" in 1936.
Stevenson's "Humus Chemistry" is the standard modern textbook on the subject.
Identify these two to easily select the correct option.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
The study of soil organic matter, humic substances, and humus development is a major field in soil biochemistry.
Several pioneering scientists established the modern theories of humification and organic matter structures.

Step 2: Detailed Explanation:
Let us analyze the scientific contributions of the listed scientists:
- (A). M. M. Kononova: A highly prominent Soviet soil biochemist who wrote the classical, authoritative treatise "Soil Organic Matter: Its Nature, Its Role in Soil Fertility and in the Methods of Its Study" (1961).
Her research laid the groundwork for understanding humification pathways, making her directly associated with humus development studies.
- (B). Selman A. Waksman: An American microbiologist and Nobel laureate who studied soil microbes extensively and published the classical book "Humus: Origin, Chemical Composition, and Importance in Nature" (1936).
He proposed the lignin-protein theory of humus formation.
- (C). F. J. Stevenson: A famous American soil biochemist who wrote the classical textbook "Humus Chemistry: Genesis, Composition, Reactions" (1982, 1994).
He is universally recognized for his contributions to the chemical characterization of humic and fulvic acids.
- (D). M. W. Beijerinck: A famous Dutch microbiologist who discovered biological nitrogen fixation (isolating Rhizobium and Azotobacter) and pioneered virology.
While he was a giant in microbiology, he is not directly associated with the biochemical theories of humus development.
Therefore, Kononova, Waksman, and Stevenson are the scientists associated with humus development.

Step 3: Final Answer:
The scientists associated with humus development are (A), (B) and (C) only.