Insect Pests of Fruit, Plantation, Medicinal & Aromatic Crops (2+1)

1. Stem girdler

1. Stem girdler - Sthenias grisator Fab. (Cerambycidae: Coleoptera)

Damage

• The grub bores into the bark and tunnels into the dry wood.
• The infestation resulted in wilting of branches and then the entire vine.
• The beetles have the habit of ringing the vines resulting in drying up of the regions beyond the cut.
Bionomics

• The adult beetle is greyish brown with white and brown irregular marking resembling the bark colour, elytra have an elliptical greyish median spot and an eye shaped patch measuring 24 mm long.
• The eggs are thrust in between barks and sapwood in clusters of 2-4 eggs by female beetle, which cuts branches slits under the bark of girdled branch.
• The egg period is 8 days.
• The hatched out grub feed inside the stem and completes its larval stage by 7-8 months.
• The total life cycle occupies more than a year.
Management

• Cut and burn the infested branches below the girdling point.
• Hand picks the beetles and destroys them which may help in migrating this longing horn beetle.
• Swab the trunk with carbaryl 50 WP 4 g / litre of water.