Snellenius manilae is a small Braconid wasp species. It looks like Cotesia except that it has a triangular closed cell on its front wing and has hairy eyes. This parasitoid wasp is host specific. It only parasitizes cutworm larvae. A female wasp lays 3-5 eggs in a cutworm larva. The parasite eats the body fluids and the larva for its development. Cocoons are formed next to the host's body. Lifecycle takes about 4-8 days. A wasp lives for about 1 week (Reissig; et. al., 1986: pp. 99-109; IRRI, 2001).
- Tachinid fly
- Ground beetle
- Praying mantis
- Weaver ant
for cutworm, count damage and freshly cut leaves, freshly cut young plants, and holes in leaves and in stems. Economic threshold level
is 2-4% plants cut below the ground or 6-8% plants cut above the soil surface (University of Nebraska, 2001). Widely accepted threshold are 2, 3, 5, and 7 cut plants per 100 plants during seedling stage (Tooker, 2009)
Management and cultural practices
- Removal of weeds in and around fields will reduce egg-laying sites and will help in the prevention of cutworm infestation. Do this at least 2-3 weeks before planting to reduce the incidence of cutworm larvae transferring to newly planted crops.
- Plow and harrow fields properly before planting. This will destroy eggs and expose larvae to chicken, ants, birds, and other predators.
- In rice fields, keep area flooded. This will prevent cutworm population.
- Plant corn, alfalfa, or beans after rice. This will provide rich fauna for beneficial insect species which will control cutworm build-up.
- Interplant main crops with onion, garlic, peppermint, coriander, or garlic every 10-20 rows to repel cutworms. Sunflowers and cosmos can also be planted as a trap crop in or around fields (Garden Guides, 2001).