Question

Give the chronological order in the development of following herbicides
A. Atrazine
B. 2,4-D
C. Bispyribac Sodium
D. Alachlor
E. Butachlor
Choose the correct answer from the options given below

• A. B, A, C, D, E
• B. B, A, D, E, C
• C. C, B, A, E, D
• D. D, B, E, A, C

Hint:

To solve herbicide timeline questions, remember that 2,4-D is always the oldest (1940s) and ALS-inhibitors like Bispyribac-sodium are relatively modern (late 1990s). This puts B first and C last, which helps identify the correct option.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
The history of chemical weed control is marked by the discovery and development of different herbicide classes over the last century, reflecting advancements in organic chemistry and plant physiology.

Step 2: Detailed Explanation:
Let us arrange the given herbicides in chronological order based on their discovery and commercial introduction:
2,4-D (B): Discovered in the early 1940s (during World War II) and commercially released around 1945. It was the first successful selective organic herbicide, triggering the chemical revolution in agriculture.
Atrazine (A): Developed by Geigy in 1958. It belongs to the triazine family and became widely used for weed control in corn and sugarcane.
Alachlor (D): Introduced by Monsanto in 1969. It belongs to the chloroacetamide class and is used as a pre-emergence herbicide.
Butachlor (E): Developed shortly after alachlor in the early 1970s. It is also a chloroacetamide herbicide used primarily in rice cultivation.
Bispyribac Sodium (C): This is a modern post-emergence ALS-inhibitor herbicide developed and registered in the late 1990s (around 1997).
Arranging these in chronological order gives the sequence: B (1945) \(\rightarrow\) A (1958) \(\rightarrow\) D (1969) \(\rightarrow\) E (1970s) \(\rightarrow\) C (1990s).
This matches the sequence B, A, D, E, C.

Step 3: Final Answer:
The correct option is (B).