Tesfaye Tesso Getachew Ayana
Eyasu Abraha Scott Bean
Ketema Belete Bedru Beshir
Solomon Derese Gebisa Ejeta
Temam Hussein Adane Legase
Tesfaye Mengiste Geoffrey Morris
Tafere Mulualem Yohannes Nugusu
Ramasamy Perumal Amare Seyoum
USDA - Agricultural Research Service
Kansas State University - Western Kansas Agricultural Research Center in Hays
Ethiopia - Ethiopian Institute of Agricultural Research (EIAR), Melkassa Agricultural Research Center, Pawe Agricultural Research Center, Sirinka Research Center, Tigray Agricultural Research Institute, Haramaya University
Sorghum is among the most important crops cultivated in Ethiopia with most of the acreages located in parts of the country prone to high temperature, frequent drought and infertile soils. The crop is grown by poor smallholder farmers whose limited harvest barely feed them year round, and food and nutritional insecurity are common occurrences. The diets of these people are predominately cereal-based with limited opportunities for supplementation with legumes or animal sources. Dietary constraints are, therefore, very severe in these communities.
In this project, a multidisciplinary team of scientists from main sorghum research institutions in Ethiopia, the USDA-ARS and U.S. land grant universities work together to exploit the wide genetic resources for high yield potential, environmental stress tolerance and improved nutritional quality available among Ethiopian sorghum germplasm. New and existing knowledge and tools on breeding and genetics, physiology and grain chemistry of sorghum is being deployed. This project has the capacity to develop sorghum varieties and hybrids with high yields, rich in digestible proteins and essential micronutrients.
This project focuses on developing and utilizing high-yielding, locally-adapted sorghum varieties and hybrids that are rich in highly-digestible protein and essential micronutrients while suiting local processing methods and diverse production systems. Through collaborative sorghum research, new innovations including the sequence of the sorghum genome, fine mapping of loci associated with Striga resistance, discovery of biochemical compounds associated with processing and utilization of sorghum grains, and the development of herbicide-resistant sorghum is being explored and utilized.
The project team has worked together to exploit the wide genetic resources for high yield potential, environmental stress tolerance and improved nutritional quality available among Ethiopian sorghum germplasm. The team has optimized food processing methods in order to maximize availability of nutrients in sorghum-based local diets. A series of interrelated activities have been implemented in the laboratory and at selected field locations in major sorghum producing regions of Ethiopia to discover unique phenotypes related to improved productivity, protein and micronutrient nutrition and developed and selected the best variety or hybrid carrying these traits.
The project team has utilized genomic tools to locate genes associated with enhanced nutritional value and reduced anti-nutritional factors, such as low protease inhibitor and phytic acid, and enhanced breeding efforts for the improvements of many of these traits. Additionally, the team has contributed to building the capacity of human resources and the institutional infrastructure of collaborating national organizations through training and mentoring graduate students to help build critical mass of scientists capable of solving local and national problems.
Ethiopian Institute of Agricultural Research (EIAR)
Six protease inhibitor (PI) genes were identified, their genomic locations determined, and markers developed to amplify them. As initial effort, a set of (57) tannin-free high- and low-digestible sorghums were selected and screened for variation in protease inhibitor genes. Association of these PI SNPs with protein digestibility showed some linkage but not strong enough to pursue a planned screening of germplasm. This is most likely due to other confounding factors that also cause differences in protein digestibility. Thus the activity was slightly modified to see the effects of natural variation in kafirin gene sequences and link this variability to protein digestibility. This effort identified four natural kafirin alleles (all of them alpha kafirins) that are strongly associated with protein digestibility. Three of these kafirin were (SORBI_3005G185600, SORBI_3005G188800, SORBI_3005G189000) were associated with improved protein digestibility and one of them (SORBI_3005G192801) with reduced protein digestibility.
Marker tools have been developed and these alleles can be tracked in breeding populations. Future efforts in improving nutritional quality should combine information not only from the kafirin genes and protease inhibitors but also from other antinutritional factors and integrate them in a way they can have synergy in enhancing protein nutrition. In particular, down regulation of gamma kafirin should be an important component of future genetic efforts to enhance protein digestibility.