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Ensuring human survival

  • 14/12/1993

Ensuring human survival Since the beginning of this century, about 75 per cent of the genetic diversity among agricultural crops has been lost.

In India, agronomists predict just ten rice varieties will soon cover three-quarters of the total rice-cultivating area in place of more than 30,000 varieties.

Rice, wheat and maize supply almost 60 per cent of the calories and proteins humans derive from plants. Humans use only 150-200 plants for food, whereas 10,000 to 50,000 are known to be edible.

From wild pineapples found in South America, breeders have imparted high sugar content and a distinct "wild fruit" flavour to cultivated varieties.

Genes transferred from a wild relative of the tomato found on the shores of the Galapagos Islands in the Pacific have conferred salt tolerance to cultivated varieties so that they can be irrigated by sea water.

Researchers at the University of California have filed a patent for thaumatin, an extract from a west African plant Thaumatococcus daniellii that is 100,000 times sweeter than sugar cane.

Deforestation of closed tropical rain forests, estimated to contain at least 50 per cent of all the species in the world, could account for the loss of as many as 100 species daily.

Forest-dwelling indigenous people employ at least 1,300 plant species for medicinal purposes. More than 60 species of plants are used to treat skin infections in the Amazon region alone.

Apart from the macadamia nut from Australia, all fruits and nuts used in western countries were first grown by indigenous people.

More than 200 varieties of sweet potato can be identified by the Ifugao tribals of Luzon in the Philippines; Jivarao farmers in the Amazon grow more than 100 varieties of cassava, and in the central Andes, upto 70 potato varieties can be found in a single locality.

Indigenous populations and their knowledge are threatened with destruction. In the Amazon region, more than 90 different groups of Indians are thought to have died out during this century.

Though the world market value of medicines derived from plants used in traditional medicine systems exceeds $43 billion, less than 0.01 per cent of the profits have gone to the indigenous people who led researchers to them.

In Europe, half of the livestock breeds that existed at the turn of the century have become extinct and a third of the remaining 770 breeds are in danger. Almost 20 per cent of the livestock breeds in the developing world are at risk.

Thailand is estimated to have as many as 1,000 species of freshwater fish, out of which only 475 have been documented. Brazil is believed to have more than 3,000 freshwater fish species -- three times more than in any other country.

It is estimated that the cost of over-exploitation of marine resources amounts to more than $30 billion annually.

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