AGRICULTURE-BRAZIL: More Plagues than in the Old Testament

By Mario Osava Reprint | | Print |

Mario Osava

RIO DE JANEIRO, Jun 12 2000 (IPS) - Brazil has identified more than 240 plagues and pests threatening its crops and blocking market access for its exports.

An Asian wood pest found in crates recently triggered alarm and led the agriculture ministry’s department of vegetable defence and inspection (DDIV) to demand tighter controls on packaging.

Another threat is posed by the carambola fly (Bactrocera carambolae) which crossed over from French Guiana but was contained in a Brazilian municipality along the border, Oiapoque, said Ilto Morandini, DDIV coordinator of plant protection.

Millions of wasps – a natural enemy of the fly – traps and checkpoints set up along the roads were all used to combat the pest.

Black sigatoka (Mycosphaerella fijiensis) whose spores are carried by the wind and which can wipe out an entire banana harvest, appeared in several places in Brazil’s Amazon jungle over a year ago. The fungus may have come across the border from Bolivia or Colombia, said Morandini.

To keep the leaf disease from spreading, the Brazilian office of agricultural research is promoting the substitution of vulnerable varieties of banana plants with strains resistant to the plague.

That is the best strategy, according to Jose Clerio, the head of a team conducting research on disease-resistant alternative varieties, because banana plants produce fruit for years and cannot simply be replaced, and chemical poisons are too costly.

In Brazil’s Amazon region, bananas are generally grown for domestic consumption or for sale at market to supply the local population.

The biggest fear is that the devastating disease could spread to areas in east-central Brazil where bananas are commercially grown. The country’s 560,000 hectares of banana plants produce around six million tonnes a year.

Bananas are the most popular fruit in Brazil – annual consumption stands at 20 kgs per inhabitant – and one of the leading fruit crops, second only to oranges in terms of output. Although less than one percent of the total yield is exported, bananas comprise an essential part of the diet of the poorest sectors of the population.

The host of enemies of agriculture include insects, bacterias, viruses, fungi, other microorganisms and crop-killing weeds. Many are inadvertently brought into the country along with imported goods, on the clothing of tourists, or in vehicles crossing the border. They later spread on their own or are unintentionally carried from spot to spot within the country.

The war is constant, without respite, and a major aspect of it entails educating the public on the risks of transporting plants or flowers from one area to another, said Morandini.

But Brazil, a huge country with a range of climates and crops, has an effective system of controls, said secretary of agricultural defence Luiz Carlos de Oliveira, who pointed to the 84 fixed and mobile checkpoints that monitor ports, airports and borders.

While the spread of pests and plagues is a global problem aggravated by the growth of trade and tourist flows, major strides have been made worldwide with respect to pest-control techniques and international standards, said De Oliveira.

But when these fail, the damages can be devastating.

In the past decade, Brazil went from an exporter to an importer of cotton, due to the boll weevil (Antonomus grandis) – a pest that nearly wiped out the entire crop in the northeast, leading to widespread unemployment in the countryside and billions of dollars in losses due to the plunge in production, the cost of imports and the rising levels of spending on pesticides, the official pointed out.

Another culprit is the citrus canker, which attacks oranges, Brazil’s leading fruit crop. As a result, this country is the world’s top exporter of orange juice, but has not been able to find markets for its unprocessed oranges.

Witches’-broom (Crinipellis perniciosa) put an end to a long period of relative prosperity brought by cacao in the northeastern state of Bahia. Brazil, the world’s leading producer of the raw material of chocolate until the 1970s, has had to import cacao in the past few years.

The costs have not only been economic, but social – due to the loss of rural jobs – and environmental – because of the need for increased application of toxic agrochemicals – as well, said Morandini.

Pests and plagues drive up production costs for farmers, reducing the country’s competitiveness on the global market, and require ongoing monitoring entailing specialised techniques, sophisticated equipment and controls against hard-to-detect microorganisms at a large number of entrypoints.

At times the phytosanitary standards enforced by countries trigger trade conflicts. The important thing is for health standards to be applied “in an adequate manner, within the limits set by international trade rules,” said De Oliveira.

The search for pest-resistant crop strains and biological controls continues, with exchanges of insects, bacterias, fungi and plants that combat the enemies of agriculture without the need for toxic chemicals.

Brazil sells French Guiana wasps to control the carambola fly, and exports to the United States flies that attack crop-destroying ants. In the meantime, it has imported more than 80 natural enemies of pests in the past decade.