Question

Which of the following combinations is not correct?

• A. Camphor -- Salvia shrubs
• B. Phlorizin -- Phyllanthus emblica
• C. Bialophos -- Microorganism
• D. Dhurrin -- Sorghum

Hint:

Phlorizin is a classical allelochemical unique to pomaceous fruit trees (Apples) where it plays a role in "apple replant disease" by inhibiting the growth of young seedlings.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Allelopathic chemicals and natural secondary metabolites are produced by specific plant species and microorganisms.
These chemicals can serve as natural bioherbicides or growth regulators.

Step 3: Detailed Explanation:
- Camphor -- Salvia shrubs (A): Camphor is a volatile terpene released by Salvia leucophylla that inhibits the growth of surrounding plants (allelo-chemical). This is correct.
- Bialophos -- Microorganism (C): Bialophos is a natural tripeptide herbicide produced by the bacteria Streptomyces hygroscopicus. This is correct.
- Dhurrin -- Sorghum (D): Dhurrin is a cyanogenic glycoside produced by sorghum plants that contributes to insect defense and allelopathy. This is correct.
- Phlorizin -- Phyllanthus emblica (B): Phlorizin is a dihydrochalcone glycoside found specifically in the root bark and leaves of apple trees (Malus species), not in Phyllanthus emblica (Indian gooseberry/Amla). Thus, this combination is incorrect.

Step 4: Final Answer:
The incorrect combination is option (B).