Lettuce

Lettuce

Scientific name: Lactuca sativa L.

Bangla/local name: Not known

Taxonomic Position according to Cronquist (1981)

Kingdom        : Plantae

Division          : Magnoliophyta

Class               : Magnoliopsida

Subclass          : Asteridae

Order              : Asterales

Family             : Asterceae

Genus              : Lactuca

Species            : L. sativa

Botanical Description of Lettuce

Habit: Biennial herb, pubescent.

Root: Tap roots.

Stem: Erect or prostate

Leaf: Simple sessile, leaves are arranged as rosette

Flower: Inflorescence head or capitulate

Involucre bract: The head or capitulum are surrounded by a whorl of bracts called the involecre thus producing a flower cluster resembling a single flower.

Fruit: Achene

Chromosome: 2n=18

Economic Importance: Used as salad and oil obtained from seeds are also useful. Lettuce leaves contain 94%, water; 1.4% protein, 2.9% carbohydrate and 0.2% fat in 100 gram fresh leaves. Each of 100 gram fresh lettuce leaves also contain 300-1500 I U carotene, 0.09 mg thiamine, 0.12 mg riboflavin, 0.4 mg niacin, 10 mg vitamin-C, 2 mg calcium and 2.0 iron (Rashid, 1999).

Table 1. Lettuce variety developed by BARI, Joydebpur, Bangladesh