The challenge of combining high-quality basic research with a mission to address the country's wider needs is embodied in the experience of UNAM's Nitrogen Fixation Research Centre, in Cuernavaca. The centre was founded in 1980 with the aim of studying the molecular basis of biological nitrogen fixation, and applying this knowledge to improve agriculture.

For the Mexican farmer, fertilizer is expensive to buy and transport, and its overuse is a significant environmental problem. Fertilizer use could be greatly reduced if the symbiosis between legumes and nitrogen-fixing bacteria could be improved or extended to crop plants other than legumes. And ultimately, if genetic engineering could give plants their own nitrogen-fixing apparatus, the need for bacteria could be eliminated.

In basic science, the centre has fulfilled its promise: its scientists have made important contributions to understanding the dynamics of the bacterial genome, the taxonomy of the bacterium Rhizobium and the carbon and nitrogen metabolism of bacteria and their host plants. As of the end of 1997, the centre — which currently has 12 full professors and 14 assistant professors — had contributed 130 papers to international journals, with about 2,200 citations.

So far, however, these discoveries have not been accompanied by corresponding improvements in Mexican agriculture. Part of the problem, says the centre's director, Georgina Hernández, is slow overall progress in this area of research. “What people thought would be possible 15 years ago turned out not to be so easy,” she says. “Genetically engineered bacteria have performed better in the laboratory and the greenhouse, but there have been problems with their ecology, and their survival in the field.”

A greater focus on farming is sought by UNAM's nitrogen fixation centre. Credit: UNAM

But some plant biologists from other Mexican institutes think that the centre's scientists have been too consumed with striving for academic excellence to pay attention to applied research. “They had the philosophy that applied research is not good for science,” says one. Another, who is disappointed that the centre has not done more to help farmers, expresses a similar view: “They are excellent scientists. They could do better if they would just focus their brilliant brains on applications.”

Hernández, who became the centre's director two years ago, acknowledges that most of its founding scientists had little or no experience of applied research. But she insists that what others interpret as a lack of interest in applications was instead a reluctance to undertake applied projects that did not have a solid grounding in fundamental research.

Whatever the reason for past reluctance, Hernández has been improving the balance between basic and applied research by encouraging collaborations with agronomists and growers. For example, strains of Rhizobium etli that have been genetically engineered to fix more nitrogen are being tested as inoculants of different bean varieties grown in Mexico, in field trials organized jointly with INIFAP, the Ministry of Agriculture's research institute.

In another new project, scientists from the centre are studying free-living nitrogen-fixing bacteria that associate with non-leguminous plants, such as sugar cane. A group of sugar cane producers is funding work to identify varieties that can derive sufficient nitrogen from bacteria to grow with little or no applied fertilizer.