Geography in the News: Diet for a hotter climate - five plants that could help feed the world

Has the world become over-reliant on rice, wheat and corn? What food plants might be more reliable against drought and disease as our planet warms?

Since human history began we have cultivated over 6,000 different plant species, yet today just three crops provide nearly half of the world's calories - these are rice, wheat and corn. However this reliance on such a small of crops has made farming vulnerable to pests, diseases and soil erosion, which thrive on monoculture.

As the impacts of climate change become more obvious farmers across the globe are embracing ancient crops and developing hybrids with may offer more reliance against drought and disease.

Amaranth: the plant that survived colonisation

This whole plant is edible - from leaf to seed, long eaten as a vegetable across Africa and Asia, and as a cereal by Indigenous Americans. The leaves can be sautéed or cooked into a stir-fry, the seed is commonly toasted and then eaten with honey or milk. It is also a great source of protein, vitamins and antioxidants. And even better - it is drought-resistant!

However Spanish colonisers banned the Aztecs and Maya from growing amaranth when they arrived in central America, but the plant continued to grow as a weed and many farmers saved amaranth seeds, passing them down for generations, until their descendants were allowed to grow it again.

Fonio: the drought-resistant traditional grain

Farmers across west Africa have been growing fonio for thousands of years - a type of millet with a nuttier taste. It is considered to be Africa’s oldest cultivated cereal and was regarded by some as the food of chiefs and kings, served on holy days such as weddings, in countries such as Senegal and Mali.

Today it is seen as a crop with many health benefits which is able to survive in poor soils with a lack of water. It is also gluten-free making a good source of amino acids for those with diabetes or who are unable to process gluten.

Cowpeas: the fully edible plant

Also known as black-eyed peas or southern peas, these have been grown in the USA since the 1940s, but in west Africa much earlier. The crop has declined in the USA but it grown widely throughout Africa, with Nigeria as the largest producer in the world.

The entire drought-tolerant cowpea plant is edible - although people mainly eat the seeds, the leaves and pods are a good source of protein, and they are being trialled in Latin American as an alternative to pinto and black beans.

Taro: adapting the tropical crop for colder climes

Taro is a root vegetable similar to the potato and is grown throughout south-east Asia and Polynesia, where rising temperatures are threatening it. Meanwhile in the US farmers (as part of the Utopian Seed Project) are trying to adapt the crop to grow in the temperate climate, where in its current form it wouldn't survive the cold winters. They are currently growing eight varieties of taro and looking for ways to help it survive the winter, in order to increase food security.

Kernza: the crop bred for the climate crisis

In 2019, the Kansas-based Land Institute, a non-profit research organization focused on sustainable agriculture, introduced Kernza. This is a crop cultivated specifically to withstand climate change. It is a perennial wheat-like grass that has been developed as a substitute for annual grains like wheat, meaning it will come back year after year, as opposed to annuals which grow once and then die.

Kernza should minimize the environmental impacts of grain production, and farmers across the mid-western USA are currently growing nearly 4,000 acres of it, although researchers are still working to improve the grain's yield.

Read the full article here - https://www.theguardian.com/en..