Question

Match the LIST-I with LIST-II \[ \begin{array}{|l|l|} \hline \textbf{LIST I (Herbicide)} & \textbf{LIST II (Mode of action)} \\ \hline A. \ \text{Imazethapyr} & I. \ \text{Photosystem II inhibitor} \\ B. \ \text{Glyphosate} & II. \ \text{ALS inhibitors} \\ C. \ \text{Clodinafop-propargyl} & III. \ \text{EPSP synthase inhibitor} \\ D. \ \text{Atrazine} & IV. \ \text{Acetyl Coenzyme A carboxylase inhibitor} \\ \hline \end{array} \]

• A. A - II, B - IV, C - III, D - I
• B. A - II, B - III, C - IV, D - I
• C. A - I, B - II, C - IV, D - III
• D. A - III, B - IV, C - I, D - II

Hint:

Always remember: Atrazine = Photosystem II inhibitor, Glyphosate = EPSP inhibitor, Imazethapyr = ALS inhibitor, Clodinafop = ACCase inhibitor.

Answer 1

The Correct Option is B

Step 1: Imazethapyr.
Imazethapyr is an ALS (Acetolactate Synthase) inhibitor herbicide, disrupting branched-chain amino acid synthesis. Hence A → II.
Step 2: Glyphosate.
Glyphosate inhibits EPSP synthase (5-enolpyruvylshikimate-3-phosphate synthase), blocking aromatic amino acid synthesis. Hence B → III.
Step 3: Clodinafop-propargyl.
This herbicide inhibits Acetyl-CoA carboxylase (ACCase), preventing lipid biosynthesis. Hence C → IV.
Step 4: Atrazine.
Atrazine is a photosystem II inhibitor, interfering with electron transport in photosynthesis. Hence D → I.
Step 5: Conclusion.
The correct matching is A - II, B - III, C - IV, D - I.