5.5 Enriched biodiversity by plant introductions

Five hundred years ago, India had no potatoes, groundnuts, tomatoes or chilliest These important crops are relative newcomers to Indian fields and cuisine.

Ports on the west coast of India-Surat, Bombay, Dabhol, Goa, Honavar, Mangalore and Cochin-have played an important role in the import and dispersal of useful exotic plants. Before medieval times, Goa traded with the African coast, Egypt, the Persian Gulf and S.E. Asia.

Despite this, the agricultural resource base of India, especially of cash crops, was very limited before Vasco da Gama's discovery of the sea route to India in 1498. The subsequent arrival of the Portuguese, British, French and Dutch intensified battles to control the seaborne trade. The Moghul empire (1526-1857) granted liberal trade concessions to foreign powers. Intense trans-oceanic and maritime trade brought exotic species to Indian shores and diversified regional plant gene-pools.

The growing demand for novel crops (such as tobacco and pineapple) led to the establishment of experimental nurseries and plantations, mostly by missionaries. The novelty and utility of many exotic plant species brought a change in the agricultural economy, food habits and cultural practices of the Western Ghats and India as a whole. By the early 18th century, the cultivation of tobacco, chillies, chickoos, guavas, sitaphals, pineapples, oranges, cashews, papayas and breadfruit was established in South India.

India became one of the world's largest producers of some of the imported crops.

Biodiversity revolution

The natural dispersal of isolated plant species is not a major factor in the spread of cultivated plants from their native countries. Human action is thus the only significant way regional plant diversity is enriched. The intercontinental exchange in plant species in the last 500 years was thus a major event in world history.

Over history, isolated wild plant gene pools have been used for strategic reasons, to bring about a calculated shift in agricultural economies of colonized areas. For instance, the Portuguese took Indian and Southeast Asian spices to Brazil for cultivation; the British and Dutch brought rubber from Brazil to Malaya and Indonesia. Other plants brought as gifts for local elites later became popular, resulting in their widespread local cultivation. These crops are now very important in their new areas, often overshadowing their role in their original homes.

Major producer of exotic crops

In 1992, India produced:

· 480 million kg of tobacco
· 8 million tonnes of groundnuts
· 5 million tonnes of tapioca
· 0.5 million tonnes of chillies
· 15 million tonnes of white potatoes
· 1.3 million tonnes of sweet potatoes
· 1 million tonnes of pineapple
· 0.3 million tonnes of cashew nut
· 1 million tonnes of tomatoes, chickoos, pumpkins, etc.

Before 1498, none of these was found in India. Today, India is among the world's major producers of many of these crops.

Conservation of introduced, economically useful plants

· Survey, document and identify introduced species and their cultivars.
· Exchange information with authorities in regions with high diversity.
· Monitor the status of endangered species in their native places and share such data.
· Freely export healthy wild germplasms to their native places for reintroduction.
· Follow up reintroduced plants until the species is established and multiplies in its original habitat.

Intercontinental maritime trade routes linking India, SE Asia, Africa and S America were also routes for the exchange of plant germplasm. This enriched regional biodiversity and revolutionized cropping pattern and the agricultural economy of many parts of the world.

Exotic species in Goa

The Portuguese rulers of Goa catalyzed intercontinental plant genetic resource exchanges. Techniques of mango grafting were improved substantially by Portuguese missionaries in Goa, helping diversify mango cultivars. Over 20% of Goa's plants appear to have been introduced by the Portuguese between 1510 and 1961.

Exotic species in Goa

Pre-Vasco da Gama (before 1498)

Major crops were limited to rice, lentils, cotton, sugar cane, wheat, jowar and bajra.
The Indian menu had no chillies, potatoes, tomatoes, peanuts, pineapples, guavas, papayas, maize, custard apples or pumpkins.
None of these plants were family or tribal totems or mentioned in literature or used in rituals.

Post-Vasco da Gama (1498 onwards)

Tobacco and pineapples were favoured by Deccan sultans and Moghul emperors.
In the 16th century, chillies, cashew, peanuts, potatoes, pineapples, papayas and other crops were introduced.
Exotic species gradually enter the Indian menu and markets.

"Vavilov centres": areas of origin of most cultivated plants

Some economically useful plants species and their original home

Prepared by Mr. Nandkumar Kamat