Growing Food: A Guide to Food Production

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industry. The oil is used as a salad oil, and in soap and margarine; the

presscake is used for animal food and fertiliser.

LIMITATIONS

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  was genetically engineered in the USA to delay the ripening process, so they
  can be picked closer to full ripeness than most other tomatoes. Genetic
  engineering (GM) has also lead to varieties with reduced amounts of the cell
  wall softening enzyme, resulting in a longer shelf life.

  
  

Botanically speaking, a fruit is defined as a mature, fertilised ovary (and its
associated structures) so that, for example, tomatoes, cucumbers and peppers are,
from a botanist s point of view, “fruits” and not “vegetables”. Other examples of
“fruits” include drupes (stony seeded fruits) such as coconuts, cherries, peaches and
mangoes, legume fruits such as peanuts and beans, and multiple fruits such as
raspberries and mulberries.
Most fruit producing plants and trees are insect-pollinated, which is the reason
they have such attractive flowers. The seed of fruits is normally dispersed by birds
and animals, which is the reason that they have attractive, edible fruits.

Seedless Fruit
Some varieties of some fruits naturally produce fruit without their flowers being
pollinated and fertilised. This produces seedless fruit and is known as
parthenocarpy; it occurs with, for example, banana, cucumber, grape, grapefruit,
orange, persimmon and pineapple. This natural phenomenon has been mimicked by
scientists in a process called induced parthenocarpy which manipulates various
growth hormones, applied either in paste form, or spray or by injection to produce
seedless fruit.
Seedless fruit from non-parthenocarpic varieties and species, and also out of
season fruit production, is also induced artificially using pollen which is either dead
or has been altered, or is from another species.
Genetic engineering is also used these days, with watermelon for example. The
seed for seedless watermelon is produced by crossing a normal diploid watermelon
with one that has been genetically modified into a tetraploid state. The triploid plants
that result from this produce seedless fruit when pollinated by normal watermelon
pollen.
In common with vegetables, most fruits have only limited food value, though
they do normally contain useful amounts of vitamins and minerals. For many
subsistence farmers (and other food producers...) fruit can also serve as a useful cash
crop.

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189 which is extracted industrially from the pulp and residues of the canning

The seed contains 24% of a semi-drying oil discussed in 2C “Oilseeds” page

Tomatoes are low in protein and calories.

The plants are susceptible to diseases, especially in warm, humid conditions.

The fruit is bulky and squashy, in other words it is not easy to transport.

The storage time is short, unless the fruit is preserved. The “Flavr Savr” type

2F. FRUITS

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GROWING FOOD – THE FOOD PRODUCTION HANDBOOK