Major collaborative wheat-breeding project bears fruit
A six-year-long project at the ACCI to breed drought-tolerant bread wheat with multiple attributes is bearing fruit. Selected elite breeding lines are now available to breeders and growers in sub-Saharan Africa.
Bread wheat (Triticum aestivum) is the second-most popular cereal crop in the world, with an estimated 700 million tonnes produced each year, but yield and grain quality are being severely affected by drought and heat stress caused by climate change. It is estimated that to keep up with increasing demand, global wheat production will need to increase by 50% in the next decade. Currently gains are less than 1% per annum.
The ACCI project, which started in 2014, is being supervised by Professor Hussein Shimelis and funded by the National Research Foundation, Water Research Commission, Alliance for a Green Revolution in Africa (AGRA), Rockefeller Foundation, ARC and UKZN. So far six students have been involved.
“The wheat breeding team is part of a collaborative research programme to breed wheat for drought tolerance, working with a research team from the Agricultural Research Council-Small Grain Institute in South Africa,” said Shimelis.
“Under this initiative, we have developed drought-tolerant bread wheat genotypes. These genetic resources have been developed in collaboration with the International Maize and Wheat Improvement Centre for heat and drought tolerance.”
Shimelis said the selected lines are now available to breeders and growers in South Africa and sub-Saharan Africa.
The project started with Dr Learnmore Mwadzingeni’s PhD research which involved conducting a genetic analysis of 100 wheat genotypes for grain yield and yield-influencing traits. These genotypes were obtained mainly from CIMMYT’s drought and heat tolerance nurseries.
Zamalotshwa Thungo and Marylyn Christian used the genotypes selected by Mwadzingeni for their own research projects, with Thungo breeding wheat for quality and drought-tolerance and Christian working on breeding silicon-efficient wheat for drought tolerance and quality.
A second collaborative part of the project has been to focus on pre-breeding wheat for enhanced carbon sequestration in the soil. The research partners involved are the ACCI, the discipline of Soil Science at UKZN, the French Research Institute for Development (CIRAD) and the Institute of Agricultural Engineering at the Agricultural Research Centre.
“This project aims to develop wheat varieties with high carbon sequestration potential and drought tolerance,” said Shimelis. “The potential outcomes include development of carbon-efficient wheat varieties through phenotypic and genomic selection, and gene introgression, knowledge creation and dissemination, and training of the next generation of crop scientists in the integration of advanced plant breeding and genetic principles with modern crop science. This will give then a skill-set to tackle climate change issues in agriculture.”
Dr Isack Mathew laid the groundwork for that by evaluating Mwadzingeni’s genotypes and identifying the ten best. These are currently being used by Kwame Shamuyarira, who has crossed them to produce 90 progeny that he is developing further. Boluwatife OlaOlorun also used Mwadzingeni’s selections for her work which involves using mutation breeding to harness the traits of drought tolerance and carbon sequestration in wheat.
“All this work is called genetic enhancement or pre-breeding of wheat for all those desirable traits,” said Shimelis.
“The goal is to develop cultivars integrating these traits. There will be another project that requires a set of methodology and nation-wide evaluation of the candidate selections.”