London - Bananas, sweetcorn and kidney beans all risk being in shorter supply because of the impact of climate change and intensive farming, scientists have warned.
Up to a third of the land used to grow bananas and maize in Africa and two-thirds of land for beans will be “unviable” by the year 2100, they claim.
As early as 2025, these crops will need to be replaced by tougher root vegetables such as yams and drought-resistant grains such as millet. Coffee production is also likely to be “drastically affected”, a report published by the Royal Botanic Gardens, Kew, says.
The State of the World’s Plants report was compiled by 80 scientists to give the first global insight into issues affecting plants today. It revealed that more than one in five of the 391 000 known plant species were threatened with extinction, mainly from disease, habitat destruction, climate change or poor farming practices.
Many species would be “on borrowed time” by 2050, it said, and plants would either become extinct, migrate to different habitats or be forced to alter their properties to adapt to rising temperatures and changing rainfall patterns.
Some plants were already in “extinction debt” – where they had been hit by global warming but the impact was not yet known, the report suggested.
Research by the International Center for Tropical Agriculture modelled how nine common crops from sub-Saharan Africa would fare over the coming decades and warned some would need to be replaced with hardier roots and grains to maintain food supplies.
Professor Kathy Willis, of the Royal Botanic Gardens, said “Having proof that root crops like cassava and yams are among the climate-smart crops of the future for sub-Saharan Africa is vital for informing policy and planning today.”
Coffee production in Ethiopia was also highly likely to be hit by climate change, another study in the report showed, but this could be counteracted with new areas for plantations.
About 2 000 species of plants are discovered every year. Last year alone, new finds included an insect-eating sundew found through Facebook, five types of onion and a close relative of the sweet potato. Invasive plants such as Japanese knotweed and cheatgrass were a global problem with nearly 5 000 species identified. These alien plants cost the UK £1.7-billion a year.
Modern farming tends to prioritise species with the highest yield which has led to a dramatic reduction in the number of ancient varieties of fruits, vegetables and cereals in existence.
A US study of 66 common crops found the number of varieties shrank by 93 percent in the first 80 years of the 20th century.
Daily Mail