**5. Planting materials and species**

Cassava does well on poor soils, and can withstand erratic rainfall. Its ability to produce good yields without fertilizer/agrochemicals and or other external resources makes it one of most widely grown staple. However, cassava's potential will not be realized until some important production constraints are addressed by high yield and well adapted cultivars. Cassava are more affected by biological restrictions than drought and high temperatures [3]. As the importance of cassava as a food, animal feed and industrial feedstock grows worldwide, there is a growing demand for varieties with specific characteristics and adaptation to different ecosystems. In Africa, new varieties are being developed as cultivation expands to dry savanna, semi-arid and subtropical regions and the transition to market-oriented production accelerates. Providing high-yielding, adapted cassava varieties to small-scale farmers via a specific system is very crucial. The system consists of three parts: conservation and distribution of genetic resources, variety development, production of high-quality and healthy planting materials and delivery to farmers.
