A perfect storm in the cotton field

A perfect storm in the cotton field

Context

Why India is the only Bt cotton-growing country facing the problem of pink bollworm infestation

The issue: Pink bollworm’s resistance to Bollgard 2

  • Bollgard 2, or BG-2, Monsanto’s second generation insecticidal technology for cotton, was supposed to protect crops against the pink bollworm, the pest has grown resistant to the toxins produced by this trait
  • Farmers now spend more on pesticides to control infestations
  • This, along with the high cost of Bt seeds, is driving farmers to indigence.

No other country faced this problem

  • They mainly grow open-pollinated cotton varieties rather than hybrids
  • They strictly terminate the crop within 160 days

Why the problem is unique to India

The pink bollworm grew resistant because India restricted itself to cultivating long-duration hybrids since the introduction of Bt cotton in 2002

What are Hybrids?

Hybrids are crosses between two crops that often see higher yields than their parents, in a genetic phenomenon called heterosis

Reasons:

  • Traits were restricted to hybrids only: When Monsanto licensed its BG and BG-2 traits to Indian seed companies, the agreement restricted the introduction of these traits to hybrids only.
  • Hemizygous hybrids:
    • Introduction of the Bt gene into only one parent of Indian hybrids results in hemizygous hybrids, which means that they express only one copy of the Bt gene
    • So, they produce cotton bolls that have some seeds toxic to the pink bollworm and some that are not
    • This can be contrasted with the homozygous seeds of open-pollinated varieties in the U.S., China or Australia, which have 100% toxic seeds.
    • Problem: Hemizygous hybrids allow pink bollworms to survive on toxin-free seeds when they are vulnerable newborns (although only a hypothesis till now)
  • Hybrids more profitable to companies:
    • Hybrids are financially more attractive to Indian seed companies because they offer a “value capture mechanism”
    • Hybrids lose their genetic stability when their seeds are replanted
    • This compels farmers to repurchase seeds each year, protecting corporate revenues.
  • Shifting to Bt cotton all together:
    • As there was no open-pollinated Bt option, the farmers were forced to shift en masse to hybrids
    • From 2002 to 2011, the area under cotton hybrids rose from 2% in north India and 40% elsewhere to 96% across the country.

Effect of this shift:

  • Low density cultivation: Not only are hybrids expensive, they are also bigger and bushier, forcing farmers to cultivate them at low densities
  • Result:To make up for these low densities longer duration is needed for the cotton crop which in turn gives more time to the pest to develop resistance

Proposed Solution

  • Only solution to the problem is to move swiftly to short-duration varieties
  • Seed companies cannot develop open-pollinated varieties with BG-2, but they can with BG, since Monsanto didn’t patent BG in India

Arguments against the above proposed solution

  • Even if BG-2 doesn’t fend off the pink bollworm, it still protects against other pests like the tobacco cutworm and the American bollworm
  • The presence of two Bt genes in BG-2 means it will be more effective than BG in delaying resistance against these pests.

Questions raised

When the whole world is moving to BG-3, why do we want to go back in time?

Even if the government incentivizes a return to BG, will all seed companies stop making BG-2 seeds?

Both BG and BG-2 can’t be cultivated together

If India cultivates both BG and BG-2, simultaneously, that can accelerate resistance among pests, studies predict. This could trigger the emergence of new cotton pests.

Conclusion

India erred by not clamping down on long-duration crops when Bt cotton was first introduced. At least now it must base its policy on sound science and implement it stringently

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