The genetic knowledge could lead to ways to improve the quality and price of tea, by selective breeding of tea plants.
Guy Barter, chief horticulturist at the Royal Horticultural Society (RHS), UK, said the work gave plant breeders a "powerful new tool".
"Once you understand the basis for the flavours and the processing quality of the tea, you can then have genetic markers that breeders can look for when trying to produce new varieties," he told BBC News.
Six main types of tea are produced from Camellia sinensis - white, yellow, green, oolong, black and post-fermented. Each has its own aroma, taste and appearance.
The distinctive flavours of these teas are created by their different chemical compositions.
Dr Simmonds said knowledge of the genome of tea helped us understand how the plant evolved.
''Another important finding is that the biochemical pathways involved in the synthesis of the compounds important in the taste of tea are also present in some of the ancestors of tea and have been conserved for about 6.3 million years,'' she said.
The first plant genome was sequenced more than 15 years ago.
Since then more than 50 types of plant have been sequenced, including food crops such as the banana, potato and tomato.