The loss of genetic diversity of the world’s food plants is an issue of serious concern with implication for the long term maintenance of global food supplies. This diversity is rapidly disappearing at a line when more genetic diversity is needed in crop breeding programmes to increase food production.
The extent of genetic erosion differ for various crops and for such erosion number of factors are responsible.
To quote few examples:
The loss of local land races for Rice, Wheat and Maize has been a serious problem in various parts of the world.
The introduction of new high yielding varieties of wheat has caused severe genetic erosion in Turkey, Iraq, Afghanistan, Pakistan and India.
90% of the native varieties of wheat have been lost in 40 years in Greece.
Some of the most valuable commercial species, particularly timber species in Ghana have suffered genetic erosion because of heavy exploitation and they are threatened with extinction in their areas of natural distribution.
For the international market Rattan’s (Lionoid palms) provide the second most important source of export earning from tropical forests of south and south-east Asia. Rattans are mainly used in the production of cane furniture for international market whereas for local uses it is used for production of mats, baskets, fish traps dyes & medicines.
Heavy exploitation combined with habitat destruction has led to the decline of major commercial Rattan species.
Medicinal plants species, to a large extent are harvested from the wild and relatively few are cultivated as crop plants. Out of total 21,000 plants tested by World Health Organisation (WHO) as medicinally important, about 5,000 higher plant mostly temperate species have been thoroughly investigated as potential sources of new drugs. However, biochemical potential of tropical plants has been largely overlooked. Nevertheless around 80% of people in developing countries rely on the traditional medicines. Over exploitation of medicinal plants extracted from the wild flora is leading to problems of genetic erosion in some of the regions. For example, in India where 2,500 plant species are used by traditional healers, some of the medicinal plants (species of Rauwolfia, Aconitum, Dioscorea & Ephedra) are under threat.
Ornamental plants are important commodity in international trade. Today, the diversity of decorative plant species established in cultivation surpasses the variety of plants commonly grown for food around the world. Total world import of cut flowers, foliage and plants amounted to Rs. 2,488 million in 1985 as compared to food, fruit and forage crops. Now, priority both nationally and internationally is given for the conservation of these genetic resources of such ornamental plants, inspite of their such economic potential.
In international trade nearly five million plants belonging to 5,000 orchid species have been recorded in CITES. Thailand is a major country for Orchids in international trade, and Dendrobium is the most heavily traded orchid genus exported. In Japan, out of 70 orchid taxa enlisted in the Japanese Red data book 50 are threatened by over collection. Orchid collection together with habitat destruction has led to the decline of wild orchid species in many other countries.
Cacti and other succulent plants including species of Aloe, Euphorbia and Pachypodium are also traded internationally. The Netherlands, Mexico, and Madagascar are the main source countries which have exported Cacti and succulent plants. This trade poses a severe threat to such plants species.
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BIO-DIVERSITY: GENETIC DIVERSITY
The loss of genetic diversity of the world’s food plants is an issue of serious concern with implication for the long term maintenance of global food supplies. This diversity is rapidly disappearing at a line when more genetic diversity is needed in crop breeding programmes to increase food production.
The extent of genetic erosion differ for various crops and for such erosion number of factors are responsible.
To quote few examples:The loss of local land races for Rice, Wheat and Maize has been a serious problem in various parts of the world.The introduction of new high yielding varieties of wheat has caused severe genetic erosion in Turkey, Iraq, Afghanistan, Pakistan and India.90% of the native varieties of wheat have been lost in 40 years in Greece.Some of the most valuable commercial species, particularly timber species in Ghana have suffered genetic erosion because of heavy exploitation and they are threatened with extinction in their areas of natural distribution.For the international market Rattan’s (Lionoid palms) provide the second most important source of export earning from tropical forests of south and south-east Asia. Rattans are mainly used in the production of cane furniture for international market whereas for local uses it is used for production of mats, baskets, fish traps dyes & medicines.
Heavy exploitation combined with habitat destruction has led to the decline of major commercial Rattan species.Medicinal plants species, to a large extent are harvested from the wild and relatively few are cultivated as crop plants. Out of total 21,000 plants tested by World Health Organisation (WHO) as medicinally important, about 5,000 higher plant mostly temperate species have been thoroughly investigated as potential sources of new drugs. However, biochemical potential of tropical plants has been largely overlooked. Nevertheless around 80% of people in developing countries rely on the traditional medicines. Over exploitation of medicinal plants extracted from the wild flora is leading to problems of genetic erosion in some of the regions. For example, in India where 2,500 plant species are used by traditional healers, some of the medicinal plants (species of Rauwolfia, Aconitum, Dioscorea & Ephedra) are under threat.Ornamental plants are important commodity in international trade. Today, the diversity of decorative plant species established in cultivation surpasses the variety of plants commonly grown for food around the world. Total world import of cut flowers, foliage and plants amounted to Rs. 2,488 million in 1985 as compared to food, fruit and forage crops. Now, priority both nationally and internationally is given for the conservation of these genetic resources of such ornamental plants, inspite of their such economic potential.In international trade nearly five million plants belonging to 5,000 orchid species have been recorded in CITES. Thailand is a major country for Orchids in international trade, and Dendrobium is the most heavily traded orchid genus exported. In Japan, out of 70 orchid taxa enlisted in the Japanese Red data book 50 are threatened by over collection. Orchid collection together with habitat destruction has led to the decline of wild orchid species in many other countries.Cacti and other succulent plants including species of Aloe, Euphorbia and Pachypodium are also traded internationally. The Netherlands, Mexico, and Madagascar are the main source countries which have exported Cacti and succulent plants. This trade poses a severe threat to such plants species.*17\218\2*