Mango stone weevil
Its grub develops hidden inside the mango stone — the fruit looks normal but the seed is bored, and infested fruit is barred from export markets.
- Pest type
- Weevil (grub in seed)
- Attacks
- Fruit → seed (stone)
- Worst in
- Fruit development
- Main risk
- Hidden seed damage; export ban
Overview
The mango stone weevil is an unusual pest because its damage is almost entirely hidden. The adult weevil lays eggs on the developing fruit; the grub bores through the flesh into the seed (stone) and completes its development inside the seed, so the fruit outside — and often the flesh — can look and taste normal.
The direct pulp loss is usually minor, but the pest matters enormously for trade: many countries treat it as a quarantine pest and reject or ban mango consignments found to carry it, shutting infested orchards out of lucrative export markets. So mango stone weevil is above all a pest of quality certification and export, and its management — orchard sanitation, destroying fallen fruit and seeds, and timed protection of the developing fruit — is aimed at keeping fruit weevil-free for market.
How to identify it
- Fruit that looks and often tastes normal outside — the damage is inside the seed, so it is easy to miss.
- On cutting the stone of a suspect fruit, a grub, pupa or adult weevil and tunnelling inside the seed.
- Sometimes a faint egg-laying mark or oozing spot on the young fruit skin.
- A history of the pest in the area or previous consignment rejections is often the first warning.
The damage it does
- Grub tunnelling inside the mango seed (stone), usually with little visible pulp damage.
- Rejection or ban of infested consignments from export markets that treat it as a quarantine pest — the major economic loss.
- Loss of access to premium markets for an otherwise good-looking crop.
- Carry-over in seeds of fallen fruit that seed the next season’s infestation.
When to act
- Protect the developing fruit during the egg-laying period, and above all keep the orchard clean.
- Collect and destroy all fallen fruit and discarded stones through and after the season — the pest survives in them.
- Where export certification matters, follow the official area-wide management and monitoring protocol.
Organic & cultural control
- Orchard sanitation is central — collect and destroy all fallen fruit and stones (deep-bury or burn) so the weevil cannot carry over in the seeds.
- Remove and destroy mummified fruit and clean up under the trees; scrape loose bark where adults hide.
- Use recommended, certified planting practices and area-wide coordination where export markets require weevil-free status.
- Follow the official area-wide management programme where one exists.
Chemical control
- Where warranted, a CIB&RC-registered insecticide applied during the egg-laying/early-fruit period reduces successful egg-laying on the fruit.
- Because the grub develops sealed inside the seed, sanitation and timed protection of the fruit are the mainstay; sprays cannot reach the grub in the stone.
- Observe the pre-harvest interval on the fruit and follow any export-market residue requirements.
- Confirm the current recommendation and programme for your area with your local KVK or horticulture/quarantine authority.
Crops most at risk
Where this problem is called out in our crop guides — open a crop for the full package of practices.
Frequently asked questions
My mangoes look fine but I hear about a weevil in the seed. What is it?
That is the mango stone weevil. Its grub develops hidden inside the mango seed (stone), so the fruit outside and often the flesh look and taste normal — the damage is easy to miss. Cut the stone of a suspect fruit and you may find a grub or weevil inside. Its main impact is on export, where infested fruit is rejected as a quarantine pest.
Why is the mango stone weevil such a big deal if the fruit looks normal?
Because it is a quarantine pest for many export markets. Even though the direct pulp loss is usually minor, countries reject or ban mango consignments found carrying it, shutting infested orchards out of lucrative export trade. So it is primarily a pest of market access and certification rather than of visible fruit loss.
How do I keep my mangoes weevil-free?
Orchard sanitation is central: collect and destroy all fallen fruit and discarded stones (deep-bury or burn) so the weevil cannot survive in the seeds and carry over, clean up under the trees, and protect the developing fruit during egg-laying with a timed registered spray. Where export certification is involved, follow the official area-wide management protocol.
Symptoms and control measures follow ICAR, KVK and state agricultural-university package-of-practices; any named chemical is a registered use. Always read the product label and confirm the dose for your crop and zone. editorial policy.