Sugarcane borers
Stem-boring caterpillars that hit sugarcane at every stage — dead heart in young shoots, a bored growing point later, and tunnelled canes that lose weight and sugar.
- Pest type
- Stem-boring caterpillars
- Attacks
- Shoots, growing point, canes
- Worst in
- All stages of the cane crop
- Main risk
- Dead heart; bored canes; low sugar
Overview
Sugarcane is attacked by a group of stem-boring caterpillars — chiefly the early shoot borer, the top borer and the internode/stalk borers — that between them tunnel the crop from germination to harvest. Which one dominates varies by region and stage, but the underlying damage is the same: caterpillars boring inside the shoots and canes, hidden from view.
In the early crop, the shoot borer bores into young shoots and kills the central growing point, producing a dry "dead heart" that pulls out easily. The top borer attacks the growing point of taller cane, causing a tuft of bunched leaves ("bunchy top") and dead heart at the top. The internode/stalk borers tunnel the mature cane, hollowing the internodes, which reduces cane weight, lets in red rot, and cuts sugar recovery. Because the borers are inside the plant, clean seed setts, resistant varieties, biological control and destroying stubble matter far more than spraying.
How to identify it
- Dead heart in young cane — a dry central shoot that pulls out easily while the outer leaves stay green (early shoot borer).
- A tuft of bunched, crinkled leaves at the top ("bunchy top") with a bored, dead growing point (top borer).
- Bore holes and frass on the cane, and tunnelled, hollowed internodes when a cane is split open (internode/stalk borer).
- Reddish discolouration inside bored canes, sometimes with red rot following.
The damage it does
- Dead heart that kills young shoots and thins the stand early in the crop.
- Bunchy top and a killed growing point that stunts the cane and cuts yield.
- Tunnelled, hollowed internodes that reduce cane weight and let red rot in.
- Lower sugar recovery from bored canes — a direct hit to the value of the crop.
When to act
- Start with clean planting — use borer-free seed setts and resistant varieties, decided before the crop even goes in.
- Scout from the early shoot stage for dead hearts, and later for bunchy top and cane bore holes.
- Remove dead-heart and bunchy-top shoots as you find them, and time biological releases to the borer’s egg-laying.
Organic & cultural control
- Plant healthy, borer-free seed setts and grow recommended resistant/tolerant varieties — the foundation of borer management.
- Release Trichogramma egg parasitoids at the recommended schedule against the shoot and top borers.
- Remove and destroy dead-heart and bunchy-top shoots, trash-mulch appropriately, and destroy stubble and crop residue after harvest to kill carry-over borers.
- Earthing-up, balanced nutrition and avoiding excess nitrogen help the crop tolerate and escape borer attack.
Chemical control
- Where borer pressure is high, CIB&RC-registered insecticides for sugarcane borers (soil/granular application for early shoot borer, timed treatments for top borer) are used per recommendation.
- Because the borers are inside the shoot or cane, timing to the young larva/egg stage and correct placement matter more than blanket spraying.
- Rotate insecticide groups and follow the label; combine chemical control with clean setts, Trichogramma and stubble destruction.
- Confirm the current recommendation for your area with your local KVK or sugarcane research station.
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
The central shoot of my young cane is dry and pulls out. Is it borer?
Yes — that "dead heart" (a dry central shoot pulling out easily while outer leaves stay green) is the sign of the early shoot borer in sugarcane. Remove and destroy dead-heart shoots to take out the caterpillars, use borer-free seed setts and resistant varieties, and release Trichogramma against the borer.
What is "bunchy top" in sugarcane?
Bunchy top is a tuft of bunched, crinkled leaves at the top of the cane caused by the top borer boring into and killing the growing point. It stunts the cane and cuts yield. Manage it with resistant varieties, removing affected tops, releasing Trichogramma, and timed registered treatments where pressure is high.
How do I keep borers from cutting my sugar recovery?
The internode/stalk borers hollow the mature cane and let in red rot, lowering weight and sugar. Prevent it from the start: plant clean, borer-free seed setts and resistant varieties, release Trichogramma, remove dead-heart/bunchy-top shoots, and destroy stubble after harvest. Because the borers work inside the cane, this integrated approach beats late spraying.
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.