Tropical fruits have been known and consumed by local habitants for many decades. Some tropical fruits have been commercially cultivated and have accounted for a great part of the country's national income. In Thailand, fruit production during the last five years (up to 1990) averaged 4.5 million tons, of which about US$ 250 million worth or about 2.5% of the production was exported.
Although there are many kinds of tropical fruits in Thailand, only about 20 species are commercially cultivated. The cultivated varieties of these tropical fruits have been selected according to the likings of the local growers. Thus the taste of the present leading fruit varieties in Thailand mainly corresponds to the fondness of the tropical Asians. However at present, there are still many indigenous plants which are botanically closely related to these tropical fruit species. If properly utilized, some of these indigenous plants could offer a great potential as genetic resources for the improvement of the existing tropical fruits varieties in Thailand.