SCIENCE/AGRICULTURE: Brazil Narrows Technological Divide

By Mario Osava Reprint | | Print |

Mario Osava

RIO DE JANEIRO, Oct 11 2000 (IPS) - Brazil has demonstrated that the requirements of agriculture, under fire from pests and international competition, can drive developing countries to reduce the technological divide separating them from the industrialised world.

Brazilian scientists took the international community by surprise this year when they finished mapping the genome of a bacterium that attacks citrus fruits, and passed nations leading the world in the area of science in other cutting-edge genetic research.

The genome programme includes a project that has mapped DNA fragments of malignant tumours in human beings faster than researchers in industrialised nations — with the exception of the United States — have been able to do so.

But the main focus of the programme are problems facing Brazil’s agriculture sector. Several harmful microorganisms are the object of the genetic research coordinated and promoted by the Sao Paulo Research Foundation (FAPESP).

The first bacterium whose genes were mapped out was the ‘Xilella fastidiosa’, which last year caused some 130 million dollars in losses, as estimated by the Citrus Crops Defence Foundation (Fundecitrus).

That first feat by the FAPESP Genome Programme was followed by similar research on other bacteria, including a plague that has long threatened Brazil’s orange groves, the citrus canker, and one that attacks sugar cane.

The genes of the witches’-broom fungus (Crinipellis perniciosa), which ruined cacao production in Brazil, and of sugar cane itself are currently being studied by hundreds of scientists in a network of university and hospital laboratories.

That is the most novel aspect of the efforts demanded by agriculture, and is part of what many scientists believe will be a key focus in the new century: life sciences, seen by many as the successor to what physics represented in the past.

Agriculture has long mobilised enormous pools of knowledge and technologies that contradict the concept that the sector is one of little added value.

Brazil has become the world’s second-largest producer of soybean, in which it is competitive despite a climate and soil previously considered less than ideal, thanks to the development of new strains and, especially, to a singular contribution by microbiologist Johanna Dobereiner.

Dobereiner, an immigrant from the former Czechoslovakia who became a Brazilian citizen in 1956, discovered over 30 years ago a bacterium that fixes nitrogen in the soil: the ‘Azotobacter paspali’.

By innoculating soybean with the bacterium, the need for nitrogen-fixing fertilisers was eliminated, saving the country an estimated total of 30 billion dollars since then.

The same principle was applied in the case of sugar cane, which thus benefited the environment with a higher output of fuel alcohol to replace petroleum derivatives, and a reduction of emissions of greenhous gases that contribute to the phenomenon of global warming.

Dobereiner passed away on Oct 5 at the age of 75, after decades of work with the National Centre of Agrobiology, located near Rio de Janeiro. In 1996, she was nominated for the Nobel Prize in chemistry. But she was not selected, perhaps because she dedicated her life’s work to a sector like agriculture in a developing country.

Brazil had to surmount many obstacles before it became the world’s leading exporter of orange juice. In the 1930s and 1940s, it lost 80 percent of its orange groves to a plague dubbed “tristeza” (sadness), spread by a virus which scientists were unable to fight, recalled Fundecitrus scientific director Antonio Juliano Ayres.

The surviving trees provided clues for the production of more resistant strains, and of a “natural vaccine,” he added.

Brazil’s citrus-growing sector, which expanded and began to export in the 1960s, wages a day-to-day battle against pests and plagues. Besides the citrus canker and “amarelinho” — the local name for the disease caused by the ‘Xilella fastidiosa’ — Fundecitrus has identified 12 threats that “in favourable conditions can cause irreversible damages.”

It also has a list of 10 insects, bacteria and fungi that threaten the country’s citrus crops, some of which are already present in countries in the Amazon jungle region.

The ‘Xilella fastidiosa’, of unknown origin, appeared in 1987 in the state of Sao Paulo, Brazil’s main orange-growing area. Strategies allowing farmers to live with the plague have been developed, but at a high cost, said Ayres.

For that reason, researchers are now attempting to map out the bacterium’s genes, in order to develop more resistant orange trees, and to act directly on the Xilella by modifying it in such a way that it is no longer a pathogen, for example, or by turning it into a killer of the insect that transmits it, he explained.

But it will take “at least five years” to come up with a definitive solution, Ayres added.

In the case of sugar cane, of which Brazil is the world’s leading producer, the prospects are broader, because the genome of the plant is in the process of being deciphered, as well as that of a bacterium that attacks sugar cane.

This is Brazil’s most ambitious genetic study involving a plant, because sugar cane is estimated to have some 50,000 genes, observed William Burnquist, head of Phytotechnics at the Technology Centre of Coopersucar, a sugar mill cooperative.

The project to map out the genetic code is to be completed by the end of 2001, and the resulting knowledge will permit modifications that could accelerate the metabolism of sugar cane, increase the sugar content, and boost resistance to disease, said Burnquist.

Brazilian sugar could thus become even more competitive. But more important, sugar cane has a future as a strategic product: a renewable source of fuel alcohol, which is gaining ground with each new rise in oil prices.