By Loucoumane Coulibaly and Alessandra Prentice
KORHOGO, Ivory Coast (Reuters) – Without pausing to wipe the sweat from their brows, workers in northern Ivory Coast picked cotton by the handful – a crop saved by the use of extra insecticides after a new plague caused record damage in western and Central Africa final season.
The Indian cotton jassid or Amrasca biguttula insect appeared out of nowhere in much of the region’s cotton belt in 2022-2023 and injected a toxin into the plants, leading to a nearly 25% year-over-year drop in production. Some countries lost more than half of their expected harvest.
“It destroyed us. It destroyed all the fields,” recalls Issouf Kabe Coulibaly, who along with other farmers in Ivory Coast’s Korhogo department struggled to support his family and racked up debt from last season’s losses.
The crisis has highlighted the region’s vulnerability to invasive species and its dependence on chemical solutions, which research shows will not protect in the long term a crop that earns millions and is a valued source of income for cash-strapped governments of Benin to Burkina Faso.
This year, the use of quickly tested and approved new pesticides has kept the tiny grasshopper-like insects at bay.
Production in the 10 cotton-producing countries of West and Central Africa is expected to reach 4.9 million 480-pound bales in 2023-2024 – a 22% recovery from the previous marketing year, the U.S. Department of Agriculture (USDA) in September.
By harvest time, in late November, the sun-drenched fields around Korhogo were so covered with cotton balls that they looked as if they were frozen. The workers worked in a line, picking the white puffs from waist-high plants and placing them in bags.
“If the medicine had not been effective, we would not have had enough cotton this year. Thank God we believe a solution has been found,” said farmer Yaridiouma Soro, whose harvest last season was about two-thirds smaller than normal.
Hesitation of farmers
When the full extent of the jassid crisis became clear last season, cotton producers knew urgent action was needed.
“The scale was unprecedented. We had never seen this before… the year was catastrophic,” said Eugene Konan, head of research and development at COIC, one of the largest Ivorian cotton companies.
There was a lot at stake. Cotton supplies 8 to 12% of the gross domestic product of Benin, Burkina Faso, Chad and Mali, according to World Trade Organization data from 2019, when the four were the region’s top producers.
Experts from the eight-country PR-PICA cotton production program joined forces to find a solution before the sowing season starts in May, testing and recommending three new pesticides for farmers in the region.
“In the short term, this is the obvious choice. This year they could not afford to lose another 30 or 50% of production,” says Thierry Brevault, who studies how to sustainably intensify crop production in the French agricultural research center CIRAD.
Across West Africa, concerned farmers treated their cotton with the new chemicals as instructed.
“We had a product to combat the bug, but we were all afraid. I reduced my area by almost 5 hectares,” says Coulibaly, who normally plants up to 15 hectares.
The USDA says similar hesitation has led to a 5% year-on-year decline in cotton acreage in Ivory Coast and an 8% decline in Benin, with some farmers switching crops entirely.
The concerns were unfounded. At Coulibaly’s farm, workers threw armfuls of cotton onto a truck headed to a depot, where it was piled up in huge chunks – a testament to the effectiveness of the new chemical regime.
“We hope that next year all our growers will participate in the cultivation again,” said Konan of COIC.
VICIOUS CIRCLE
However, the recovery may be short-lived and researchers warn that more work needs to be done to find long-term solutions.
Insecticides should only be used against Amrasca biguttula with caution as known cases of resistance have been reported in India and Pakistan, the Industry Group Insecticide Resistance Action Committee (IRAC) said.
“In West Africa, the answer remains the use of insecticides… But it doesn’t really solve the problem. It’s a vicious circle,” Brevault said by phone.
“Sooner or later we will encounter resistance. Ultimately, these products will no longer work.”
Developing pest-resistant cotton varieties, expanding the use of monitoring systems so that chemicals are used only when necessary, exploring alternative biocontrols and learning how to tackle jassids in a different part of their life cycle should be priorities, he said .
The economic argument for investing in sustainable instruments is clear. Biological invasions cost Africa up to $79 billion between 1970 and 2020, mainly due to the damage they caused, according to a 2021 study in the journal Niobiota that warned such costs increased exponentially over time.
“We can expect more and more new invasive species to come to the region – to West African countries,” says entomologist Lakpo Koku Agboyi of the non-profit Center for Agriculture and Bioscience International (CABI).
He said this was partly due to weak border controls that allowed non-native species to hitchhike from elsewhere unnoticed, and global warming, which can change a species’ range or boost its spread.
Genetic tests show that the new jassid in West Africa made its way from Asia, although it is not known when this happened or what caused the population explosion, said Brevault, who ruled out climate change as a factor.
Some farmers in Korhogo are wary of the chemical approach to pest control.
“For me, it’s the pesticides that are not very effective,” said 70-year-old Navaga Tuo, standing in a field that was more brown than white. He decided to plant corn this season after losing much of his cotton in 2022-23.
Encouraged by his neighbors’ bountiful harvests, Tuo plans to return to cotton next season and protect his crop as directed, but he worries about using more chemical sprays.
“We have to find a solution to eradicate the jassids. We have no other profession except agriculture,” he said, plucking corn cobs from dried out stalks and throwing them on the ground.
(Reporting by Alessandra Prentice and Loucoumane Coulibaly, editing by Alexandra Hudson)