Sesame gall fly
A tiny midge that turns sesame flower buds into swollen galls that never open or set a capsule — each galled bud a lost seed capsule.
- Pest type
- Midge (maggot in bud)
- Attacks
- Flower buds
- Worst in
- Flowering stage
- Main risk
- Galled buds; lost capsules
Overview
The sesame gall fly is a tiny midge that attacks sesame at flowering. The female lays an egg in a developing flower bud; the maggot feeds inside, and the bud responds by swelling into an abnormal, fleshy green "gall" instead of developing normally.
A galled bud never opens into a proper flower and never forms a seed capsule, so every attacked bud is directly a lost capsule and lost seed. Because the maggot develops hidden inside the bud, and damage is fixed once the gall forms, control has to be timed to the flowering/bud stage when the adults are laying, and combined with removing and destroying galls to break the cycle. It often occurs alongside the sesame leaf webber, so the two are managed together.
How to identify it
- Swollen, abnormal, fleshy green galls in place of normal flower buds — the buds enlarged and deformed.
- Galled buds that never open into flowers and never set a seed capsule.
- A tiny maggot inside when a gall is opened.
- Damage appearing at the flowering stage, often alongside webbed shoots of the leaf webber.
The damage it does
- Flower buds converted to galls that produce no flower and no capsule — direct loss of seed.
- Reduced number of capsules per plant, cutting seed yield in proportion to the galls.
- Loss fixed once the gall forms and cannot be recovered.
- Compounded loss where it occurs together with the sesame leaf webber and capsule borer.
When to act
- Watch the flowering stage, when the adults lay in the buds — this is the only window to protect the buds.
- Scout for the first galls and act promptly, removing them before more adults emerge.
- Manage it together with the sesame leaf webber, which attacks at overlapping stages.
Organic & cultural control
- Remove and destroy galled buds as they appear to take out the maggots and reduce the next generation.
- Grow recommended tolerant varieties and sow at the recommended time to reduce coincidence with the fly.
- Destroy crop residue and volunteer sesame after harvest, and spray neem at flowering to deter egg-laying.
- Conserve natural enemies by avoiding unnecessary broad-spectrum sprays.
Chemical control
- Time any spray to the bud/flowering stage, when the adults are active — once the maggot is inside a gall, no spray reaches it.
- CIB&RC-registered insecticides for sesame, applied at flowering (often the same programme as for the leaf webber), help protect the buds.
- Rotate insecticide groups and observe the pre-harvest interval on the seed crop.
- Confirm the current recommendation and dose for your area with your local KVK.
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 sesame flower buds are swollen and never open. What is it?
That is the sesame gall fly. Its maggot develops inside the flower bud, which swells into an abnormal green gall instead of opening into a flower — so no capsule and no seed form from it. Open a gall and you will find a tiny maggot. Remove galled buds to reduce the next generation, and protect the buds at flowering when the adults lay.
Why does each galled bud matter so much?
Because a galled bud never becomes a flower or a seed capsule — it is directly a lost capsule and lost seed. So the yield loss is in proportion to the number of galls. Since the damage is fixed once the gall forms, the key is to protect the buds at flowering and to remove galls promptly before more flies emerge.
Can I manage it together with the sesame leaf webber?
Yes — the sesame gall fly and the leaf webber/capsule borer often attack at overlapping flowering and capsule stages, so a flowering-time management programme (neem, removal of galls and webbed shoots, and a rotated registered insecticide timed to flowering) addresses both. Managing them together is more practical and effective than treating each separately.
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.