About Leaf Miner

The adult is a small brownish gray moth.
Each female moth lays about 200 eggs. Shiny white eggs are laid singly, usually on the underside of the leaflets, close to the midribs, and are just visible to the naked eye (Fig.).
The young larvae mine into the leaves as soon as they hatch.
If a mine is opened, the minute caterpillar can be seen inside.
The mines enlarge as the larvae grow.
When they become too large to occupy the mine, the larvae emerge and web adjacent leaflets.

Crop Damage

 

The young larvae mine into the leaves and feed on the leaf tissue.
The infestation is usually detected by the presence of small brown blotches on (or in) the leaf.
A severely attacked field looks 'burnt' from a distance.
Epidemics can result in total crop loss. Leaf miners are favored by the hot dry conditions of the post-rainy season.

Management

Growing resistant varieties like ICGV 86031.
Consider the role of natural enemies.
Minute white specks like parasites can be seen attached to the outside of the larvae.
Postpone the spray if more than 50% of the larvae are parasitized.
Meanwhile closely monitor the development of the pest population.
Resistant Variety on the right and a susceptible one on the left.
Chemical control is recommended if five or more active larvae per plant are found up to 30 days after seedling emergence (DAE), 10 larvae per plant at 50 DAE, or 15 larvae per plant at 75 DAE or later.
Dimethoate at 200-250 mL a.i./ha or Monocrotophos at 150-200 mL a.i./ha should be applied if groundnut leaf miners are observed over the threshold populations.