Adenium Obesum Literature Review

Chapter 2
LITERATURE REVIEW
2.1 Adenium obesum
Apocynaceae is also generally known as Dogbane which is distributed mostly in the tropical regions. This family has 480 genera and 4,800 species around the worldwide and it is divided into 5 subfamilies. The 5 subfamilies are Rauvolfoideae, Apocynoideae, Periplocodeae, Secamonoideae and Asclepiadoideae. Each subfamily has its own characteristic, such as vines, perennial herbs, woody climbers, and shrubs. However, all of the subfamilies will contain latex which is usually clear, and milky. Leaves of this family are usually simple which petiolate and sessile exist in the axil. The axil of vein is usually clustered adaxially with the petioles and the flowers are commonly showy in colour. Seeds of these subfamilies are distinctive with a tuft of hairs at the end. Adenium is come from the subfamily of Apocynoideae (Endress and Bruyns, 2000). There are few varieties of Adenium species, such as Adenium boehmianum, Adenium multiflorum, Adenium oleifolium, Adenium swazicum and Adenium obesum.

Adenium boehmianum is commonly can be found in southern Angola and northern Namibia. This species of succulent scrub can grow until 1.5 m tall and it also has a swollen stem. The leaves are 80 to 140 mm long and 50 to 80 mm broad. The flowers usually have a pink in colour

Temperature is the first physical culture condition to be observe. Based on Hurd and Graves (1985), different temperature level applied will influence the pattern of crop yield as it will affect the rate of developmental events, such as fruit ripening and rate of fruit growth (Adams, Cockshull and Cave, 2001). Li et al., (2010) conducted an experiment to study the influence of temperature on germination of black pepper (Piper nigrum L.) seeds under a controlled enviroment. The result of the study showed optimal temperature for the seed germinate was between 30 and 350C (Li et al,.