By Patricia Grogg
HAVANA, Jun 26 2002 (IPS)

Cuba has reduced its farmers’ use of agro-chemicals by 75 percent in the last two decades as a result of the progress made in biologically-based insecticides and fungicides, which are paving the way for farm production that is healthier for humans and the environment.

The use of chemical agents dropped from 40,000 to 10,000 tons annually as a result of an integrated pest management system that has been in effect since 1982 to control some 90 species that are harmful to crops.

This scheme includes a planting calendar that takes into account the most appropriate timing to prevent pest infection, as well as other new cultivation methods.

The system entails the study of each harmful agent and the best method to fight it with traditional non-chemical pesticides and biological agents – based on plants and bacteria – produced by the National Institute for Plant Health Research.

One notable case is the drastic reduction in methyl bromide, a potent fungicide gas that is applied to crops like tobacco and damages the ozone layer in the earth’s atmosphere, which protects life on the planet from the sun’s ultraviolet rays.

Methyl bromide is one of the substances monitored by the Montreal Protocol, an international accord that has been in effect since 1987 aimed at ending the use, production and trade of ozone-depleting substances.

Tobacco growers in the eastern Cuban province of Pinar del Río and of Havana have cut their use of this fungicide by 62 and 18 tons, respectively. They are now using alternatives like biological products to keep harmful organisms away from tobacco leaves.

“Not only are chemical products more expensive, but they also tend to create resistance in the insects or fungus, so require constantly higher doses,” Pablo García, a small farmer outside the capital, told IPS.

Plant health experts say that the application of greater quantities of chemical pesticides multiplies the risk of poisoning humans, it deteriorates the soil and favours the emergence of other plant diseases.

Experts say that the increase in ecological methods for protecting crops from their natural enemies marks a return to Cuba’s historic farming tradition.

Intensive farming, an approach the island’s authorities began to encourage in the 1960s and early 1970s, pushed up the demand for agro-chemicals.

In that period, pest control was based exclusively on synthetic, chemical-based pesticides, almost entirely ignoring the traditional biological methods developed throughout generations of farming on this Caribbean island.

One of the consequences was the emergence of new farm pests in Cuba. In the mid-1970s, the creation of the State Plant Protection System gave rise to a notable decline in the use of chemical pesticides.

In addition to the farming and environmental problems, the economic problems of the 1990s motivated a further reduction in the use of such products, 85 percent of which had been imported from the Soviet bloc, which was dismantled in 1991.

Between 1991 and 1998, chemical pesticide imports varied from 6,000 to 12,000 tons a year, with a yearly average of 8,375 tons, according to the Institute for Plant Health Research.

The socialist-run island now has 280 laboratories, known by their Spanish acronym as CREEs, that produce biological pesticides.

The CREEs, essential in the fight against harmful insect and fungus infestations of crops, are distributed throughout the country, 53 in areas of sugarcane production (sugar is a key Cuban export), and 227 in zones producing fruit and other crops.

In recent years, programmes have encouraged the planting of the Nim tree in agricultural areas. The trees serve as a natural pest control, repelling insects with the scent of their leaves and fruit, and as windbreaks, preventing wind erosion of the soil.

Using the seed of this tree native to India, farmers prepare a simple biological substance to fight a set of insects, including the ‘bibijagua’, a native ant species that is harmful to crops.

The products derived from the Nim tree also have proven effective in controlling insects, mites and nematodes that affect vegetable fields.

This focus on environmentally friendly farming has fomented the growth of urban agriculture, which provides a large portion of the fresh fruits and vegetables consumed in the cities.

The biological pesticides facilitate plantings in densely populated areas, where the use of chemical-based products would pose a serious threat to human health.

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