Breeding Sorghum Using Induced Mutations: Future Prospect for Namibia

摘要

In arid and semi-arid regions of the world sorghum stands out as a climate change-ready crop with high potential for the production of food, feed, fodder, fiber and fuel in the face of increasing human population. The present review highlights induced mutation breeding technique as a potential tool for improving sorghum in Namibia. The review discussed the following issues; crop improvement using mutagens, mutant screening, selection and evaluation, impact of induced mutation breeding, factors for declining production and future implication of sorghum mutation breeding. In Namibia, severe drought stress resulting in total crop failure ha s become frequent. This is partly a consequence of farmers growing crop varieties which cannot withstand impact of drought. As such Namibia has limited drought tolerant varieties available for the diverse agro-ecologies. Farmers keep growing the familiar landraces which performs well in good rainfall years but fails to produce stable yield with irregular and erratic rainfall. Thus, breeding new sorghum varieties of high yield and quality combined with multiple agronomic traits including pest and disease resistance and high efficiency in nutrient and water use is needed. Induced mutation is one of the breeding methods utilized worldwide to supplement conventional breeding for developing superior varieties with desirable traits in different crops. Development of high yielding, drought tolerant, and dwarf sorghums with early maturity enables effective utilization of available soils moisture and in optimizing plant density for achieving higher yield in farmers’ fields. Recombination breeding through exploitation of natural genetic variability and mutation breeding to reduce the plant height without disturbing agronomic superiority of elite lines is recommended for sorghum improvement in Namibia.