Breeding Sorghum Using Induced Mutations: Future Prospect for Namibia

Abstract

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 has 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 How to cite this paper: Wanga, M.A., 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.

The Effect of Single and Combined Use of Gamma Radiation and Ethylmethane Sulfonate on Early Growth Parameters in Sorghum

“…It is a high-yield semi-dwarf and early-maturity cultivar [43]. Meanwhile, the genotype Red sorghum is a late-maturity cultivar widely cultivated in Namibia [44], and the genotypes Parbhani Shakti, Parbhani Moti and ICSV15013 have unique traits including high contents of grain Fe and Zn and are currently being tested for wider adoption and drought tolerance.…”

Genetic x environment interaction on agronomic characters and yield components of sweet sorghum (Sorghum bicolor) mutant strain

“…According to Carvalho et al (2002), the identification and selection of individual mutations, understanding the genetic control of the characters for the purpose of improvement, and confirmation of the desired character changes are important factors that determine the success of new varieties assembling through mutations. Mutation induction to obtain disease-resistant sorghum, droughttolerant and shorter stress has been previously reported by Human and Sihono (2010) and Wanga et al (2018). Genetic variations in terms of morphological and physiological characters such as chlorophyll (albino, viridis, striata) mutations; leaves mutations (narrow, wide); morphological mutations (dwarfs, tall, twin rods), panicle mutations (twin panicles, compact, spread), and seed mutations (pink, brown, long, round, small) in the 2 nd generation of mutants have been obtained by irradiation at a dose 400 Gy in local sorghum (Htun et al 2015).…”

“…Previous study has produced drought-tolerant sorghum mutants by using the irradiation technique on the Dura variety, and putative mutants tolerant to acid soils with sugar Brix for about 10.50-11.95% (Human and Sihono 2010). Wanga et al (2018) used the irradiation techniques to induce the mutation and subsequently obtained the drought-tolerant new varieties of local sorghum in Namibia. This work with a number of sorghum mutant strains produced by the irradiation technique combined with in vitro showed the success story indicated by the greater agronomic characters and yield compared to the elder and also another check variety.…”

Improving French bean yield potential through induced mutagenesis using EMS and SA

“…Given these attributes, there is a significant opportunity to enhance their economic viability for farmers by harnessing their yield potential through induced mutagenesis. The effective utilization of induced mutation breeding has been demonstrated as a successful approach for enhancing locally adapted cultivars of sorghum (Wanga et al, 2018). Therefore, the objective of the present study was to generate high-yielding French bean mutants with broadened genetic diversity from a local, non-descript Phaseolus vulgaris L. cultivar through EMS and SA mutagenesis for breeding purposes.…”