By Andy Challinor
The most extreme El Niño weather current in history has officially been declared over, but has left some 100 million people facing severe food and water shortages in its wake. But we cannot rest easy as another, less headline-grabbing phenomenon, is already underway.
Gradual yet steady warming of the planet is posing an equally significant threat to our food supply. Our crop breeding programmes, which develop crops that will survive in high temperatures, are simply not keeping up.
In recent years, our ability to predict future climate scenarios has improved greatly. For example, we now know that mean temperatures in Africa are expected to rise faster than the global average, and may reach as high as 3°C to 6°C greater than pre-industrial levels. This is the good news: at least we know what is coming.
The bad news is that we have much less time than we might think to get our food systems prepared to adapt to these latest projections. In fact, research out this week shows that maize crops currently being bred will be out of date by the time they get into the field, in terms of their response to rising temperatures. 1.2 billion people in sub-Saharan Africa and Latin America depend on maize as a staple food. Yet climate change is advancing quicker than we are able to breed and disseminate heat resistant varieties. As if breeding was not already complicated enough – needing to respond to complex cultural and market preferences – we now need to pay closer attention to future climate scenarios to ensure these improved seeds are fit for purpose.
As we face our eighth consecutive hottest month on record, we should be feeling the heat both literally and figuratively and accelerate the pace of our crop research accordingly.
A range of solutions are available to rectify this worrying situation. First, there are several opportunities for reducing the amount of time it takes to breed new crop varieties and get them into circulation – which currently stands at up to thirty years. Using marker aided-selection for example, that allows certain traits to be identified and used, as well as involving the farmers who will use the new seeds in a “participatory” breeding approach, have both shown promise for achieving this. New varieties could also be bred in warmer temperatures, so that they develop more heat stress tolerance along the way. This efficient solution is now being tested by teams in Zimbabwe, Kenya, and Ethiopia and shows much promise. Mitigating future climate change to within the agreed “safe limit” will also ensure that new crop varieties can survive. This will become particularly important in the second half of this century, when changes we make now in reducing emissions will begin to show their effects.
But none of this will be possible without significant funding. The Green Climate Fund was set up at the Cancun climate talks in 2010 to help developing countries adapt to and mitigate future climate change, yet it still has not supported agricultural research (instead focusing on clean energy, water and land restoration projects). This could be one so far untapped resource.
Of course, we cannot claim that breeding alone will solve the food shortages that record temperatures are causing; indeed some crops will simply not be suitable for cultivation in some areas of the world by as soon as 2050. Improved seeds can only contribute to food security and farmer incomes if other challenges such as access to finance and market access are also addressed in tandem.
With this in mind, existing heat and drought tolerant crops can have tremendous impact on rural livelihoods especially for smallholder farmers. For example, the Drought Tolerant Maize for Africa project is now being used by two million farmers in 13 African countries, helping them grow enough food to feed their families and sell on the surplus – even at times when rains are erratic or scarce.
We cannot let the next phase of breeding efforts become futile. While this research only examines maize crops in certain regions of the world, it should raise alarm bells for many other global staple crops, which are also at risk of being outpaced by our changing climate. We urgently need to link climate scientists, crop modellers and breeders to identify which traits will be needed where over the next 30 years, and work collaboratively to ensure that they are successfully bred into the future crops on which we will rely.