Question

Diameter of nucleocapsids in Baculoviruses is
(A) 30-60nm
(B) 0-25nm
(C) 65-90nm
(D) 90-120nm

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

Hint:

Baculoviruses (like NPV) are "Rod-shaped." Remember the small diameter (30-60nm) but long length. They are the most effective "insect-specific" viruses used in agriculture.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Baculoviruses are a family of large, rod-shaped viruses that infect insects, primarily those in the order Lepidoptera. They are widely used as biological control agents (NPV and GV).
Detailed Explanation:
The structure of a Baculovirus consists of a nucleocapsid (the protein shell containing the dsDNA genome) which is then enveloped.
These enveloped virions are often embedded within a large protein matrix called an occlusion body (polyhedra).
Measurements of the nucleocapsid itself have established a consistent size range for the family Baculoviridae.
The diameter of the rod-shaped nucleocapsid is typically between 30 and 60 nm.
The length of the nucleocapsid is much greater, ranging from 250 to 300 nm.
Options (C) and (D) represent diameters that are too large for the internal nucleocapsid structure of these viruses.
Option (B) is too small to accommodate the large circular double-stranded DNA genome characteristic of Baculoviruses.

Step 2: Final Answer:
The diameter is in the range of 30-60 nm. Thus, (A) only is correct.