Tomato

Tomato (Lycopersicon esculentum Mill.) is one of the most important
vegetables worldwide. World tomato production in 2001 was about
105 million tons of fresh fruit from an estimated 3.9 million ha. As it
is a relatively short duration crop and gives a high yield, it is economically attractive and the area under cultivation is increasing daily.
Tomato belongs to the Solanaceae family. This family also includes
other well-known species, such as potato, tobacco, peppers and eggplant (aubergine).
Tomato has its origin in the South American Andes. The cultivated
tomato was brought to Europe by the Spanish conquistadors in the
sixteenth century and later introduced from Europe to southern and
eastern Asia, Africa and the Middle East. More recently, wild tomato
has been distributed into other parts of South America and Mexico.
Common names for the tomato are: tomate (Spain, France), tomat (Indonesia), faan ke’e (China), tomati (West Africa), tomatl (Nahuatl),
jitomate (Mexico), pomodoro (Italy), nyanya (Swahili).
Tomatoes contribute to a healthy, well-balanced diet. They are rich in
minerals, vitamins, essential amino acids, sugars and dietary fibres.
Tomato contains much vitamin B and C, iron and phosphorus. Tomato
fruits are consumed fresh in salads or cooked in sauces, soup and meat
or fish dishes. They can be processed into purées, juices and ketchup.
Canned and dried tomatoes are economically important processed
products.

Tomato (see Figure 1) is an annual plant, which can reach a height of
over two metres. In South America, however, the same plants can be
harvested for several years in succession. The first harvest is possible
45-55 days after flowering, or 90-120 days after sowing. The shape of
the fruit differs per cultivar. The colour ranges from yellow to red.

Three different types of tomato plants can be distinguished:
? tall or indeterminate type
? semi-bush or semi-indeterminate type
? bush or determinate type
The tall and bush types are entirely different kinds of crops.
The tall varieties are the best choice for a long harvest period. They
keep growing after flowering. This feature is called indeterminate.
However, under tropical conditions, diseases and insect attacks will
stop growth. The plants generally have more foliage. This will keep
the temperature lower within the crop and the fruits grow in the shade
of the leaves. Because they are covered, the sun does not damage the
fruits and they ripen more slowly. Slower ripening and a high leaf/fruit
ratio improve the taste of the fruits and in particular the sweetness.
The tall types have to be staked, caged or trellised (see Chapter 4).
Short types usually support themselves and need no staking. Under
severe weather conditions such as typhoons, however, staking may be
advisable. Determinate types stop growing after flowering. They require less labour, so they are popular for commercial cultivation. They
have a relatively concentrated fruit set which lasts only two or three
weeks and the fruits ripen much faster than those from indeterminate
types.
Advantages of tomato:
? relatively short duration vegetable crop
? short or long production period
? can be grown as an uncovered field crop and in protected
cultivation
? fits easily into different cropping systems
? has high economic value
? has high micronutrient content
? fruits can be processed, dried and canned