Botany. Sesame (Sesamum indicum L.) belongs to the family Pedaliaceae. Locally it is called til in Urdu and Punjabi, tir in Sindhi, konzola in Pashto, and kunjit in Balochi. It is an annual minor kharif oilseed crop. The stem is erect, variously shaped, 60-120 em tall, and branched.
In sandy soils the roots develop more profusely than in clay soils, which imparts drought resistance to sesame. Flowers on short peduncles are borne singly in the axils of leaves of the upper portion of the stem and branches. The fruit, a capsule, varies from 2.5 to 8.0 em in length and 0.5 to 2.0 em in diameter. Capsules mature from bottom to top, allowing shattering of the lower ones by the time the uppermost capsules are mature. The seeds are small and ovate, weighing 2-4 grams per thousand seeds.
Cultivars with different coloured seeds are available. In Pakistan there are two distinct types, cream-coloured and black. Cream-coloured seeds are preferred. Seeds are present in hairy capsules, each with 4-8 locules. The plant has indeterminate growth habit; therefore the capsules do not mature uniformly. Because of this characteristic, shat- tering is one of the main constraints in sesame cultivation.
Origin and history. It is generally accepted that sesame originated in . the Ethiopian region; others, though, think that the centre of origin was the Afghan-Persian region (Mehra 1967). Identification of sesame seed in excavations in Harappa (Pakistan) shows that it was cultivated in 2000 B.C. (Vats 1940). As the crop has a long history dating back to prehistoric times, many countries or regions are claimed to be the centre of origin. This question is discussed in considerable detail by Weiss (1983).
Key reference : Crop Production