The Twisted Flower That Warned Bhaskar in Time

Last year, Bhaskar found out at picking time.

He had four acres of Bt cotton in a village outside Warangal, and the plants looked tall and healthy right through October. The squares came, the flowers came, the bolls swelled. Then the pickers started opening bolls and calling him over. Inside, the lint was stained yellow and brown. Two locules out of four were eaten. In some bolls, a small pink caterpillar curled up next to a ruined seed.

The trader at the market yard rubbed his kapas between his fingers and quoted a lower rate. Close to ₹1.6 lakh spent on seed, fertiliser, four sprays and picking, and a crop worth far less than planned. His son's engineering fees were due in January.

This year, he decided, he would not wait for the pickers to tell him.

What is pink bollworm, and why is it so hard to see?

Pink bollworm is a small moth whose caterpillar lives inside cotton flowers and bolls, so most of the damage happens out of sight. By the time you see it from outside, much of it is already done.

Its life cycle, in plain words:

• The moth is small, greyish-brown and flies at night.
• Eggs are laid on flower buds, flowers and young bolls.
• The young caterpillar bores straight in. In a flower, it ties the petals together with silk, so the flower stays twisted and half-open. Farmers call this a rosette flower.
• Inside the boll, it eats the seed and stains the lint. The entry hole is tiny and often closes over, so the boll looks normal from outside.
• The caterpillar survives in leftover bolls, stalks and seed after the season, and comes back as moths next year.

That is why one careless neighbour can keep the pest alive for a whole village.

Why doesn't Bt cotton protect against it any more?

Bt cotton was designed to kill bollworms, but in many cotton-growing areas pink bollworm has become resistant to it, so Bt alone no longer gives full protection. It still helps against some other bollworms, but you cannot rely on the seed to do all the work.

Bhaskar had believed the opposite. "It's Bt, the worm won't come," his seed dealer had said years ago, and he had never questioned it. Now he knew better.

How Bhaskar caught it early this time

In the second week after flowering started, Bhaskar walked his field with his phone in one hand and a small knife in the other. Near the border with his neighbour's field, he found it: a flower that was not opening properly, its petals twisted together like a closed umbrella.

He photographed it in Mapis Farming. The diagnosis came back with pink bollworm rosette flower as the most likely cause, and a next step: open the flower and check for a small larva inside, and open a few green bolls from the same plants.

He pulled the petals apart. A tiny white-pink caterpillar wriggled out.

Last year the pickers found it. This year a single twisted flower told him, two months earlier.

He marked the plant with a strip of cloth, saved the photo and his note in his scouting record, and called the agriculture extension officer that same evening.

How to scout for pink bollworm, step by step

Scouting means walking your field on a fixed day each week and looking at the same kind of things, so you can see whether the problem is growing. Here is the routine Bhaskar now follows from the start of flowering:

1. Walk the field in a zig-zag, not just the border. Check plants from every part of the field.
2. Count rosette flowers. Note how many twisted, half-open flowers you see out of the flowers you checked.
3. Open green bolls. Pick a few well-grown green bolls from different plants and cut them open. Look for larvae, eaten seed and stained lint.
4. Remove and destroy rosette flowers and damaged bolls you find. Don't drop them in the field; put them in a bag and burn or bury them.
5. Write it down the same day, with the date and the numbers. A photo and a line in your farm record are enough.

The numbers matter because your officer decides on spraying based on them, not on how worried you feel.

How do pheromone traps help?

A pheromone trap uses a lure that smells like the female moth, so male moths fly in and get caught. Counting the moths every few days tells you when the pest is building up, often before you see damage.

Bhaskar's officer advised a few traps across his four acres, checked regularly, with the lure changed when the label says. The traps are for monitoring, not control. When the catch kept rising for several nights, together with his rosette flower counts, the officer told him it was time to act.

What is the IPM plan for pink bollworm?

Integrated pest management (IPM) means using several methods together, so you need fewer and better-timed sprays. For pink bollworm, the plan covers the whole year, not just the flowering weeks:

• Sow on time, and together with your neighbours. Very early or very late sowing gives the moth a continuous supply of flowers.
• Plant the refuge seeds that come with your Bt seed packets. They slow down resistance for everyone.
• Scout weekly from flowering, as above, and use pheromone traps.
• Remove rosette flowers and damaged bolls by hand while numbers are low.
• Ask about biological and mating-disruption options. In some areas, officers and KVKs recommend egg parasitoids or products that confuse the male moths. Ask what is available and proven in your district.
• Spray only if the threshold is crossed, using a product approved for cotton, at the dose on the label, and change the chemical group between rounds. Your agriculture officer or Krishi Vigyan Kendra will tell you the local threshold and the right product.
• End the crop on time. Don't keep the crop going for extra pickings or let it regrow as a ratoon. Late flowers feed the next generation.
• Destroy the stalks and leftover bolls after the last picking. Shred or bury them; don't store stalks with bolls near the house or cattle shed.

Bhaskar sprayed once that season, on his officer's advice, and only after both his traps and his counts showed the build-up. Last year he had sprayed four times, mostly by guessing.

What changed in Bhaskar's field

His crop this year was not perfect. A few bolls near the border still had damage, and his neighbour's late cotton will be a problem unless they both pull their stalks on time. But his kapas was cleaner, he spent less on sprays, and the trader did not frown.

More than the money, he now trusts what he sees. Every week has a date, a photo and a count. If you want to start this habit, read why a simple farm diary pays off next season. And if a season does go wrong, the same dated photos help with crop insurance claims.

Frequently asked questions

What are the first signs of pink bollworm in cotton?

The earliest clear sign is the rosette flower: petals tied together with silk so the flower stays twisted and half-open. Inside green bolls you may find small pink or white larvae, eaten seeds and stained lint, so cut a few bolls open each week.

Does Bt cotton still control pink bollworm?

Not fully. In many cotton areas, pink bollworm has become resistant to Bt cotton, so damage can happen even in Bt fields. You need scouting, traps, timely crop termination and residue destruction alongside it.

How do pheromone traps work for pink bollworm?

The trap holds a lure that smells like the female moth, which attracts and catches male moths. Counting the catch regularly shows when the pest population is rising. Traps are mainly for monitoring, and your agriculture officer uses the counts, together with flower and boll damage, to decide whether spraying is needed.

Why should cotton stalks be destroyed after harvest?

Pink bollworm caterpillars survive the off-season inside leftover bolls, stalks and seed. If stalks and bolls stay in the field or are stored near the house, the moths come out next season and attack the new crop. Shredding or burying residue soon after the last picking breaks this cycle.

Can I identify pink bollworm damage with a phone photo?

Yes. A clear daylight photo of a rosette flower or an opened boll can be checked with photo diagnosis in Mapis Farming, which suggests the likely pest and next steps. Confirm by opening the flower or boll yourself, and talk to your agriculture officer before spraying.