Pink Bollworm Infestation in Bt Cotton

What is the issue?

India is the only Bt cotton-growing country facing the problem of pink bollworm infestation.
A look into the various factors that make it a problem unique for India and the consequences therein is essential.

What is the infestation concern?

The pink bollworm infestation is plaguing cotton farmers.
Monsanto is an American agro-tech company that released the Bt cotton in India.
Bollgard 2 or BG-2 is Monsanto’s second generation insecticidal technology for cotton.
BG has a single bacterial gene called CryA1C, and BG-2 has CryA1C and Cry2AB2.
Both are designed to protect the crop against pink bollworm.
But the pest has grown resistant to the toxins produced by this trait.
BG began failing against the pest in 2009, and BG-2 began failing in 2014.

What is the significance?

Cost - As a result of this, farmers now spend more on pesticides to control infestations.
This, along with the high cost of Bt seeds, is driving farmers to deprivation.
India - Interestingly, none of the other 14 Bt cotton-growing countries have seen this resistance.
China still successfully controls pink bollworm with first-generation Bt cotton.
The U.S. and Australia are moving on to third-generation BG-3 without having faced this problem.

Why is it a problem unique for India?

Hybrids are crosses between two crops that often see higher yields than their parents, in a genetic phenomenon called heterosis.
All other Bt cotton-growing countries mainly grow open-pollinated cotton varieties rather than hybrids.
But India restricted itself to cultivating long-duration hybrids since the introduction of Bt cotton in 2002.
This is said to be the reason for the pink bollworm growing resistant to toxins in India.

What are the factors behind?

Agreement - Monsanto licensed its BG and BG-2 traits to Indian seed companies.
The agreement restricted the introduction of these traits to hybrids only.
Cropping pattern - When Monsanto introduced Bt cotton in India, the technology was so popular.
Many cotton farmers shifted to it in large numbers.
However, absence of open-pollinated Bt option forced many farmers 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.
Seed protection - India is the only country whose intellectual property laws have never prevented its farmers from either saving or selling seeds.
Other countries restrict saving and selling of seeds in various degrees.
Some countries allow farmers to reuse seeds from a protected plant variety, but not to sell them.
In the U.S., where plant varieties are patented, the patented seeds cannot even be reused.
Seed Companies - Without seed protection mechanism, several seed companies in India prefer hybrids.
This is because unlike open-pollinated varieties, hybrids lose their genetic stability when their seeds are replanted.
This compels farmers to repurchase seeds each year and in a way protects corporate revenues.

What are the consequences?

One adverse consequence is resulted from the cost of the hybrids.
Density - Besides, hybrids are also bigger and bushier.
This forces farmers to cultivate them at low densities of 11,000 to 16,000 crops per acre.
This is suboptimal, as countries like the U.S. and Brazil plant cotton at 80,000 to 100,000 per acre.
The low densities also drive Indian farmers to grow them longer so that they produce enough cotton.
Toxicity - The introduction of the Bt gene into only one parent of Indian hybrids, as is the practice, is itself a problem.
The resulting hybrids are hemizygous, which means that they express only one copy of the Bt gene.
They thus produce cotton bolls that have some seeds toxic to the pink bollworm and some that are not.
Unlike this, the homozygous seeds of open-pollinated varieties in the U.S., China or Australia have 100% toxic seeds.
The problem is hemizygous hybrids allow pink bollworms to survive on toxin-free seeds when they are vulnerable newborns.
But this is only a hypothesis, and experiments are needed to confirm this.

How does pink bollworm affect crops?

When all the above factors combine with the pink bollworm’s biology, it creates favourable conditions for resistance.
The pest does its most damage in the latter half of the cotton-growing season.
It does not consume any other crop that grows then.
So, the long duration of Indian cotton crops, between 160 and 300 days, allows this pest to thrive and evolve resistance.
Contradictorily, other cotton-growing countries strictly terminate the crop within 160 days, arresting resistance growth if any.

What is the way out?

The National Seed Association of India suggested the government to encourage a move back to Bollgard.
Notably, Monsanto has not patented BG in India.
Farmers should move swiftly to the short-duration crop varieties.
This is where Monsanto’s first-generation Bollgard comes in.
Seed companies cannot develop open-pollinated varieties with BG-2, but they can with BG as Monsanto did not patent BG in India.

What are the challenges?

Moving back - Some say that when the many countries are moving to BG-3, moving back to BG in India would be a bad idea.
This is because the problem was not with the BG trait but with long-duration cotton.
Pests - Even if BG-2 does not fend off the pink bollworm, it still protects against other pests like tobacco cutworm and 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.
Resistance - Another challenge is that even if government incentivises a return to BG, the seed companies are unlikely to stop making BG-2 seeds.
If India cultivates both BG and BG-2, simultaneously, that may accelerate resistance among pests.
This could trigger the emergence of new cotton pests.
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.

Source: The Hindu