THE replacement of indigenous varieties of crops, fruits, vegetables and livestock species by high-yield crop varieties and improved breeds of animals, in the past few decades, has depleted agro-biodiversity. Indigenous varieties and livestock species have lost their significance due to intensification of farming and separation of local communities from indigenous biological resources.
Agro-biodiversity has a major role in providing food and promoting food security for the future. Agro-biodiversity for food and agriculture comprises various biological diversity components like crops, fish, livestock, pests, inter-acting species of pollinators, predators and competitors among others. About 20,000 species of plants, fungi and animals have been identified for their medicinal importance; and pharmaceutical industry is based on these biological resources and related local knowledge. Plants are the potential food resource for both humans and animals. It is interesting to know that about 30,000 plants species have edible parts but only 7,000 plants have been collected or grown as food throughout the history, of which only 20 species provide 90 per cent of the world’s food. Wheat, rice and maize supply 60 per cent of the world food requirements.
The food security is threatened by rapid decline of biodiversity through introduction of exotic species, loss of gene pool, neglected/underutilised species, monocultures and bio-fuels. The introduction of uniform, high-yielding varieties has resulted in the loss of 75 per cent of plant genetic diversity as farmers have worldwide replaced their multiple local varieties and landraces with these varieties. These varieties led to the deterioration of the environment as they required more water, high input of chemical fertilisers and pesticides which increased salinity, waterlogging and also resulted in depletion of nutrients.
The well adapted old cultivars have been replaced by few genetically modified varieties and breeds. New species are ranked second to habitat destruction in threatening the biodiversity as they exclude native species by competing with native flora/fauna for resources. Some plants like Mesquite have made cultivated lands vulnerable to cultivation while others like eucalyptus and parthenium retard seed germination and plant growth of native plants by releasing allelopathic chemicals. It has also resulted in the introduction of new pests like mealy bug.
Livestock is so severely affected that about 30 per cent of its breeds are at risk of extinction and six breed, worldwide, are lost each month. Domestic animals are decreasing at the rate of five per cent and tropical forests at the rate of one per cent. About 70 per cent of marine species are fully exploited and nearly 60 per cent of the earth’s coral reefs are threatened by humans. According to estimates 34,000 species of plants or 12.5 per cent of the world’s flora are facing extinction. The diminishing biological resources will diminish food sources of the communities and this will lead to food insecurity.
The introduction of bio-fuels in the last few decades has helped solve the problem of energy insecurity and climate change but the increased conversion of agricultural commodities to biofuels resulted in an increase of international food prices.
According to the World Bank, about 70-75 per cent of the increase in food commodity prices from 2002 to 2008 was mainly due to biofuels. The use of biofuels has decisively contributed to a rising demand for sugar, maize, wheat, oilseeds, and palm oil and this food/fuel competition could be observed as global wheat and maize stocks are declining considerably.
Agriculture intensification has reduced crop diversity to few varieties in Gilgit-Baltistan region of Pakistan. Buck wheat was grown on wide scale earlier but now it is rarely seen in the fields of the region because farmers are keen to grow potatoes and high-yielding wheat varieties which have made their fields susceptible to pests and diseases. The infestation of the pests like codling moth and wooly aphids in apples, Botrytis leaf virus in onions, crown gall disease in cherries and nematodes in potatoes are the effects of agriculture intensification. The market oriented agriculture practices, during the last few decades in the region, have replaced traditional self-sustaining agriculture systems.
Support to farmers is required as they play a key role in the protection of precious resources. It should be provided as a means of meeting the survival needs of ever increasing population. They should be given subsidy to encourage them to grow old, neglected and underutilised crop species like pearl millet, finger millet and sorghum etc. Biopiracy and patents on living organisms should be prohibited as well as the prohibition of the development of sterile varieties through genetic engineering processes. The government should redesign policies and take serious efforts for the conservation of biodiversity in the country. The establishment of gene bank at regional levels and promotion of research related to evaluation of national germplasm would help in this regard.
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