In Kiboko, Kenya, a barbed wire fence separates a field of hybrid corn from the surrounding lands. Inside the fence, food safety regulators are learning to grow the crop with little water. In recent years, droughts have hit the region between June and September, reducing yields.

But two new varieties of corn, also known as maize, are coming to sub-Saharan Africa. One of them is conventionally bred; the other, better-yielding variety is genetically modified. Both are drought-tolerant and the seeds are royalty-free. Together with other agricultural interventions, they have the potential to feed some of the 300 million people for whom the plant is a staple.

There is now a great rush in parts of the continent to get biosafety regulations in place before the transgenic corn arrives on commercial markets in 2017.

Sylvester Oikeh, based in Kenya, is an agricultural scientist and the project manager for the drought-tolerant maize initiative (called Water Efficient Maize for Africa, or WEMA), run by the African Agricultural Technology Foundation. He described the promise of the Kenyan fields in a phone interview.

"Maize happens to be one crop in Africa that is consumed by more than half of the population, and it is badly affected by drought," he said. "With climate change, the problem will become worsened."

The initiative has big names behind it. The Gates Foundation and Warren Buffett fund it. Monsanto developed the crop for North American farmers using a gene from the lowly Bacillus subtilis bacterium, which is found in dirt.

For a region such as northeastern Uganda, which has seen its twice-in-a-decade drought cycles arrive once in two years, yield matters a lot. Corn is grown in rain-fed regions that already feel the ill effects of climate change on their agricultural output, according to Oikeh.

The fear of droughts and heat in the future

"The food crisis of 2008 was a harbinger of things to come," said Nina Fedoroff, the science and technology adviser to U.S. Secretary of State Hillary Rodham Clinton. "The impact of climate change is just beginning to be factored in."

With a burgeoning population, water scarcity, rising numbers of meat-eaters in the developing world, and greater competition for land, agricultural productivity needs to increase dramatically. The first green revolution of the 1970s was an easy accomplishment in comparison to this one, according to Fedoroff.

Climate change will deliver a triple curse on agriculture, forcing crops to deal with rising temperatures, droughts and the rising salinity of water in parts of the world. The numbers speak for themselves. By the end of the century, the average global temperature will be 3.5 degree Celsius above normal.

The optimal temperature for photosynthesis is 20 to 25 degrees Celsius. By 2080, the average temperature in Uganda, for example, will rise to 29 degree Celsius (an increase of 4.3 degrees above the current average), according to a report by U.K. Department for International Development and LTS International.

The rise in temperature will be accompanied by erratic rainfall and increasing drought, the likes of which have already been seen in the country, according to the report.

"A third of the world's population already lives in dry lands," said Fedoroff. "The shape of the future is pretty daunting."

Land near the tropics fares worst

Other experts agree. Charles Godfray, a professor at the Department of Zoology at Oxford University who recently co-authored a paper in the journal Science about the challenges of feeding 9 billion people, said that the impact of climate change on agriculture will be negative. Although warming will open up lands in cooler regions for cultivation, it will not compensate for the loss of water and land in areas near the tropics, he said.

"The current system of agriculture is not sustainable," he said. "Water is arterial. We will run out of water in parts of the world."

There are many ways to get greater productivity. The rise of precision farming, conventional breeding techniques aided by biotechnology, improved irrigation and genetically modified crops are all important in helping the world cope with its food challenges, said Godfray.

In 2008, constrictions in the food supply chain led to a spike in global prices and riots around the world. The situation will only get worse. Drastic improvements in agriculture are necessary to cope with increased demand in a complex world. South Asia and sub-Saharan Africa will be worst hit.

In Africa, improving infrastructure, better fertilizer use, improved irrigation and other constraints can be relieved to increase yield. But the continent is drought-prone, with millions of farmers relying on rainfall for their crops grown in small land holdings. Corn is most widely grown, with almost 300 million people in sub-Saharan Africa using it as the main source of food. And it is grown in rain-fed regions prone to crop failures.

"Africa is greatly in need of transgenic crops," said Oikeh. "The way our agricultural productivity is declining, there is no other way than to look for the best of science and technology to address the problem now."

Racing to stay ahead of food demands

In the medium term, conventional crossbreeding helped by molecular biology techniques (a technique called "marker assisted breeding") may suffice. But such methods take time. Where it would take about 10 years to develop a transgenic crop, it will take twice that time to develop a similar plant using marker assisted breeding.

Wild relatives of crops could be better suited to harsher climes, but efforts to collect and breed such crops are just beginning. And sometimes, the traits are just too complex to replicate. Multiple genes can feed into a single trait. Other times, the desired trait, such as the ability to resist certain pests, can be absent in plant genomes.

Molecular biologists and neutral policymakers expect genetically modified (GM) crops to occupy an important role in the future. Currently, there are about 30 commercial crops worldwide. By 2015, the number will increase to 120, according to the European Commission's Joint Research Centre.

"Would you get rid of surgery?" Robert Zeigler said when asked if GM crops were dispensable. He is the director-general of the International Rice Research Institute based in the Philippines, an organization that was instrumental in helping Asia increase its rice yields during the first green revolution. "With GM, you have a powerful tool that offers the potential for most people on the planet to be fed, and decrease the footprint, and live comfortably."

Enter Bacillus subtilis. The bacterium's genome resembles corn in at least one respect. Despite millennia of evolution between them, both contain the genes for the CspB protein, which helps the organism adapt to stress. For a plant, there are few greater stresses than a lack of water.

Looking for plants that tolerate stress

Inside the cells of a corn plant, tiny molecules called RNA relay messages to help with cell activity. But during drought, the molecules are misshapen and unstable. The CspB protein grabs the molecules and stabilizes them, allowing the RNA to fold neatly into their proper shape. Photosynthesis happens at a greater rate. There are more kernels in a given ear of maize.

The gene was developed by Monsanto to increase yield by 10 percent in North America. The scientists in Africa are placing this proprietary gene inside drought-resistant corn developed by non-transgenic breeding techniques by a Mexico-based research center called CIMMYT. The scientists hope that the resulting crop will increase yield by 30 percent, according to Oikeh.

"In the five countries we are operating [South Africa, Mozambique, Uganda, Kenya, Tanzania], that should give us an additional 2 metric tons of maize that can feed 14 to 21 million people," said Oikeh. "If this is used around Africa, we will have higher benefit than that."

Despite its promise, the only nations in Africa that could bring a GM crop to market are Egypt, South Africa and Burkina Faso, according to Guillaume Gruere, a research fellow at the International Food Policy Research Institute. Others do not have a government body in place to set up the rules needed to commercialize a transgenic crop.

"My big uncertainty is whether there will be regulation in place when they get ready," said Gruere. "In those African countries, we work a lot there in setting up regulations that would be functional, but it's not there yet."