Anisopteromalus calandrae

Anisopteromalus calandrae is a parasitic wasp belonging to the family Pteromalidae. Within the context of agricultural science, it is classified as a beneficial insect, or parasitoid, rather than a pest, as it is a natural enemy of various stored product pests.

This species primarily targets larvae of major grain-destroying beetles, including the rice weevil (Sitophilus oryzae) and the maize weevil. Its ability to detect and parasitize larvae hidden inside individual grains makes it a highly effective tool for reducing post-harvest losses in warehouse environments.

The life cycle involves the adult female using her ovipositor to locate the host larva hidden within the grain kernel. Once identified, she paralyses the host and deposits her eggs on its surface. The developing wasp larva then consumes the host, effectively stopping the grain damage before the beetle can reach adulthood.

From an agronomic perspective, utilizing this parasitoid is a pillar of Integrated Pest Management (IPM) in grain storage. By managing the population of A. calandrae, farmers and storage managers can significantly decrease the need for toxic chemical fumigations, ensuring safer and more sustainable agricultural storage practices.

Best practices for the management and application of this parasitoid include:

• Maintaining ambient storage temperatures between 25°C and 30°C for optimal development.
• Ensuring grain moisture levels are conducive to the activity of both host and parasitoid.
• Avoiding the use of broad-spectrum insecticides that could eliminate beneficial wasp populations.
• Strategic releases in areas identified with high infestation rates of grain weevils.