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lettuce

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lettuce

1. any of various plants of the genus Lactuca, esp L. sativa, which is cultivated in many varieties for its large edible leaves: family Asteraceae (composites)
2. the leaves of any of these varieties, which are eaten in salads
3. any of various plants that resemble true lettuce, such as lamb's lettuce and sea lettuce
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005

What does it mean when you dream about lettuce?

Lettuce is a slang word for money. Depending on the dreamer’s association with this symbol, the dream may indicate fruitfulness or financial matters.

The Dream Encyclopedia, Second Edition © 2009 Visible Ink Press®. All rights reserved.

lettuce

[′led·əs]
(botany)
Lactuca sativa. An annual plant of the order Asterales cultivated for its succulent leaves; common varieties are head lettuce, leaf or curled lettuce, romaine lettuce, and iceberg lettuce.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Lettuce

 

(Lactuca sativa), an annual vegetable of the family Compositae. The species is descended from L. serriola, which grows wild in Western and Southern Europe, Southwest Asia, and North Africa. In the USSR L. serriola is found in Siberia (as far as the Altai region), Middle Asia, and Transcaucasia. Lettuce is cultivated almost throughout the world. It is raised in all parts of the USSR.

Lettuce develops a rosette of radical leaves and, later, a strongly branched flower-bearing stem measuring 60–120 cm tall and having a large number of small inflorescences (heads). The flowers are yellow and bisexual, and the fruit is an achene with a pappus.

Lettuce is a cold-resistant plant; its shoots can withstand temperatures to - 5°C. The plant requires a lot of light and moisture. Soils with a neutral reaction and rich in organic matter are most suitable. The leaves, which are used fresh in salads, contain many vitamins (C, B, PP), carotene, and salts of iron and phosphorus. The yield is 300–500 quintals per hectare.

There are several types of lettuce. Leaf lettuce (var. secalina), which forms a rosette of leaves but not a head, has a vegetative period of 30 to 40 days. A garden form of leaf lettuce is Moscow Hothouse. Head lettuce (var. capitata) forms a round or flat-rounded head; its vegetative period is 55 to 95 days. Garden forms include Bettner, May, Yellow Stone Head, and Berlin Yellow. Cos lettuce (var. romana), which has a elongate-oval head, includes the forms Paris Green and Ballon. Its vegetative period is 70 to 100 days.

Lettuce is grown in open or sheltered ground. It is planted in the central part of the European USSR in the open ground with a vegetable seeder in late April or early May and shortly before the onset of winter. The most common variety is Grand Rapids. Care includes thinning, loosening the soil, weeding, and watering.

Leaf varieties are harvested all at once; heading varieties are harvested as each head forms. The earliest harvests are obtained by sowing coated seeds before winter and covering the plantings with a film in the spring. Cos lettuce is grown for autumn and winter consumption. It is sown in open hotbeds in late June or in the open ground. Moscow Hotbed and head varieties are raised in sheltered ground.

In the central part of the European USSR lettuce seeds are sown in early January in hothouse flats. In southern regions the seeds are sown similarly but in December. When the plants have two to four leaves, they are set out in a permanent place. The crop (1.5–5 kg per sq m) is harvested in late February or in March. For hotbed cultivation, the seeds are sown in January in greenhouses and set out in the hotbeds in March. The crop (2–3 kg per sq m) is harvested in early April.

REFERENCE

Markov, V. M. Ovoshchevodstvo. Moscow, 1966.

V. I. RUMIANTSEVA

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
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References in periodicals archive
Phytotoxic and cytotoxic effects of Eucalyptus essential oil on Lactuca sativa L.
Se determino que la dosis optima de ALA de lodo residual fue de 0.1%, la cual no genero efectos adversos en el poder germinativo ni en la germinacion de semillas de lechuga (Lactuca sativa L.) variedad Hardy, y tampoco ocasiono efectos de toxicidad en el crecimiento normal de las plantulas de lechugas germinadas.
Valarini, "Avaliacao da Contaminjao de Coliformes Fecais Em Alface (Lactuca Sativa), Agua de Irrigacao E Lavagem Em Sistemas de Producao Organica E Convencional," Revista Brasileira de Agroecologia, vol.
The [IC.sub.50] (concentration of extract required to inhibit 50% of Lactuca sativa growth) was used for comparison of the activity of the different extracts from cultivar BR-1.
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