DOHA//Professor Rajendra Pachauri, the chairman of the Nobel prize-winning Intergovernmental Panel on Climate Change, thinks Arab states should shore up their food security as global warming places stress on the world's agricultural resources. But he is not thinking of recent government initiatives to buy fertile farmland in other countries. Instead, Dr Pachauri suggests Arab oil exporters invest in tracts of scrub-land at home. "We've got to convert oil wealth into soil wealth," he told the 9th Arab oil conference in Doha earlier today. "The soil quality is poor, but can be improved substantially, enhancing food security." To illustrate what could be achieved, even in the arid Qatar peninsula, Dr Pachauri displayed a slide of lush greenery in the Dukhan region in the south of the emirate, near its biggest onshore oilfield. The natural landscape of the region is sabkha, a type of salt flat. But by inoculating this unpromising substrate with specially selected types of fungus, researchers have succeeded in growing a number of plant species, including vegetables, at a project located amid otherwise barren desert. They did not even have to add much water. The New Delhi-based Energy and Resources Institute, of which Dr Pachauri is the director general, was involved in the Dukhan demonstration project, which converted 4,000 square metres of "hyper-saline waste-land" into a productive habitat with vegetation, earthworms, insects and birds, in a matter of 18 months. The naturally occurring fungi, called mycorrhizae, attach themselves to plant roots. There, the fine fungal filaments greatly enhance the ability of the roots to absorb water and minerals. The host plants, with the help of sunlight and their special green pigment, chlorophyll, combine those with carbon dioxide to make sugars. Some sugar is transported back through the plants' roots as food for the symbiotic mycorrhizae. The mutually beneficial association enables the plants to grow longer roots to tap underground water, and sometimes to make use of water too salty for plants without mycorrhizae to tolerate. The desert agriculture experiment at Dukhan was far from commercial, but could lead one day to commercial applications. "It all depends on how effectively new technology is harnessed," says Dr Pachauri. Taking this a step further, is there any reason why crops grown in fungally enhanced desert soils could not be sources of biofuel?