Question

Neanastatus grallarius and Platygaster oryzae are the natural parasitoids of which of the following pest?

• A. Beet armyworm
• B. Rice gall midge
• C. Pink bollworm
• D. Green Leafhopper

Hint:

Remember that Platygaster oryzae is the most famous and effective egg-larval parasitoid associated with the biological control of the rice gall midge.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Biological control involves using natural enemies like parasitoids, predators, and pathogens to suppress pest populations below economic injury levels.
Identifying key parasitoids for major crop pests is a central theme in biological pest management.

Step 2: Detailed Explanation:
The rice gall midge, Orseolia oryzae (Diptera: Cecidomyiidae), is a highly destructive pest of rice in India and other Asian countries.
In nature, its populations are kept in check by a complex of beneficial parasitoids:
1. {Platygaster oryzae (Hymenoptera: Platygastridae) is a highly efficient, gregarious egg-larval endoparasitoid of the rice gall midge. The female parasitoid lays her eggs inside the gall midge egg. The parasitoid larvae complete their development inside the host larva, eventually killing it before it can pupate.
2. {Neanastatus grallarius (Hymenoptera: Eupelmidae) is a pupal or late-larval ectoparasitoid of the gall midge, attacking the pest inside the hollow "silver shoot" gall.
These two parasitoids play a critical role in natural biological control, often achieving high parasitism rates in the field.

Step 3: Final Answer:
Therefore, they are natural parasitoids of the Rice gall midge.