Guest essay by Eric Worrall
The humble potato is apparently so adaptable to different climatic conditions, NASA scientists are conducting serious tests, to see if the hardiest varieties could grow on the planet Mars. My question – what does this radical adaptability say about climatic food resilience, back here on Earth?
Echoing Ridley Scott’s The Martian, Nasa is running tests to see if potatoes could survive the climatic extremes of the red planet
“The Martian is completely possible,” says astrobiologist Julio Valdivia-Silva, the principal scientist working on the experiment in Peru.
Valdivia-Silva says the technology is growing at an “exponential” rate just as efforts to learn more about Mars are gathering pace.
Valdivia-Silva and his team aim to replicate Mars-like conditions on earth using a dome to create the same atmosphere, and soil consisting of sands brought from the Pampas de la Joya desert, part of the Atacama desert in southern Peru and one of the world’s driest and most nutrient-poor ecosystems.
Why the potato? The resilience of the humble spud combined with its huge number of species, genotypes and varieties means it can be grown from sea level to 4,700 metres above sea level while resisting drought, extreme heat and cold, salinity and UV radiation. It is also pound-for-pound one of the most nutritious staples as it is packed with vitamin C, zinc, iron, proteins and carbohydrates.
But Mars may be a whole new league of inhospitability. Temperatures on the planet vary wildly, between a high of 20C (68F) at its equator in summer to a low of -153C at the poles, according to Nasa . Its atmosphere is 95% carbon dioxide, 3% nitrogen and just 0.13% oxygen, which means the potatoes may grow fast but end up undersized. In addition, the dusty planet lacks ground water and there are winds of up to 60mph.
Water might be the biggest issue. Air pressure on Mars is so low, any liquid water usually just boils away. Even attempting to trap the water vapour in a plastic greenhouse, like the movie “The Martian”, might not help. All the potatoes I have ever grown love their water. But these conditions, low pressure, low water boiling point, extreme dryness, also apply to a lesser extent to the thin air of the High Andes, the source of some of the varieties of potatoes being tested.
One thing for sure – if a major, staple food crop is so adaptable, there is a realistic chance of growing it on another planet, claims that a few degrees global warming might cause mass starvation are utterly implausible. Absolute worst case, we might all have to develop a taste for more potatoes.