Question

Given below are two statements: Statement (I): Mulberry silk worm is a monophagous insect that feeds only on Morus spp. Statement (II): Eri silk worm is another insect that feeds only on Ricinus communis. In light of the above statements, choose the most appropriate answer from the options given below.

• A. Both Statement (I) and Statement (II) are correct.
• B. Both Statement (I) and Statement (II) are incorrect.
• C. Statement (I) is correct but Statement (II) is incorrect.
• D. Statement (I) is incorrect but Statement (II) is correct.

Hint:

Remember that Eri silk is also called "peace silk" or "non-violent silk" because the moths are allowed to emerge naturally from their cocoons before processing. Its polyphagous nature makes rearing more flexible than the monophagous mulberry silkworm.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Host specificity is a key biological trait of insects.
Monophagous insects feed exclusively on a single plant genus or family, whereas polyphagous insects feed on plants across multiple families.
These host relationships are important in sericulture, as the larvae of different silk-producing moths require specific host plants to produce high-quality silk cocoons.

Step 2: Detailed Explanation:
Let us analyze both statements:
Statement (I):
The domesticated mulberry silkworm, Bombyx mori, is highly monophagous.
Its larvae feed almost exclusively on the leaves of plants in the genus Morus (mulberry).
The physiological development and silk production of Bombyx mori are adapted to the nutritional profile of mulberry leaves.
Thus, Statement I is correct.
Statement (II):
The Eri silkworm, Samia ricini, is a polyphagous insect.
While castor (Ricinus communis) is its primary and preferred host plant, the larvae can also feed on several alternative host plants from different families.
These alternative hosts include:
- Cassava (Manihot esculenta, family Euphorbiaceae)
- Kesseru (Heteropanax fragrans, family Araliaceae)
- Payam (Evodia flaxinifolia, family Rutaceae)
Because Samia ricini can feed on several plants other than castor, stating that it feeds "only" on Ricinus communis is incorrect.
Thus, Statement II is incorrect.

Step 3: Final Answer:
Statement I is correct, and Statement II is incorrect.
This corresponds to Option 3.