Farming in cities could help feed the world

If climate change begins to limit the global production of food and energy crops, it will be necessary to develop a new system of food production.

Imagine agriculture in small spaces, using high-tech tools such as photo-bioreactors, generating clean products 24 hours a day, every day, regardless of external climatic factors. Imagine that this would be free of pathogens and agrochemicals, independent of the seasons, and with the possibility of growing genetically modified crops without interacting with the environment or affecting existing biodiversity.

This is “urban biofarming”, a kind of high-tech agriculture primarily developed for big cities.

Food production and food security were under threat from urbanisation and population growth even before the prospect of a global climatic catastrophe. With this in mind, we at the University of Antioquia in Medellin, Colombia, have been conducting a series of investigations into differentiated cell and tissue culture for the cultivation of future food and energy products.

So far, our work has focused on using cell culture to produce cocoa, the oil of the Barbados nut Jatropha curcas, and orange juice. Other plant species in the pipeline include sugar cane, corn, wheat and barley. These efforts could be a milestone in demonstrating the feasibility of urban biofarming.

Limits to genetic modification

One solution to the potential failure of conventional agriculture is genetic modification, which can make crops resistant to environmental extremes, such as droughts or floods.

However, it is unrealistic to expect this to be developed for every kind of food. This would require huge financial resources, lots of scientific research, and long periods of time for the crops to pass all the necessary biosecurity protocols before they can be planted in fields in direct contact with the natural environment. The crops would also need to adapt well and have high enough yields to feed the world.

Genetically modified organisms face another obstacle: they are the focus of considerable social concern. We should really look elsewhere for the answer.

The alternative could be plant biotechnology - specifically, the in vitro culture of cells and tissues of edible parts of certain crops or fruit. As yet, however, there is little scientific literature on such research.

Cell culture also allows the synthesis of new natural products, makes it possible to create “bio-factories” to convert low-value crops into high-value products and generates new compounds not normally produced under natural conditions. You can generate new products that do not exist in the market today - for example, mixing cocoa cells with almond cells to generate a cocoa-almond taste product. You can also induce the cells by using compounds called precursors to produce other new compounds by way of biotransformation.

Commercial production

The use of cell culture has already had a big impact on research in physiology and biochemistry, especially in studies of cellular metabolism and work to determine the effect of substances such as plant hormones on cellular responses.

In genetics, cloning has allowed the improvement of cell cultures through the fusion of protoplasts - plant cells from which the cell wall has been removed - and genetic transformation. Progress has been so good that with modern techniques it is now possible not only to culture free cells, but also to allow cell division in an isolated culture and use this to grow whole plants.