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This research was made possible with the financial assistance
of the ARC and the Winter Cereal Trust.
The milling and baking industry is a highly sophisticated industry that involves complex
processes and characteristics which require wheat with a good extraction and flour yield.
However, the production of high quality wheat is not economically sustainable for the producer
and unless something is done to rectify the situation, local wheat production will continue
to decline.
Genetic improvement of wheat
The genetic improvement of wheat is extremely difficult, in part due to the complexity of
the wheat genome and in part due to the fact that yield is the result of interaction between
genetics and the environment.
Wheat yield is a polygenic characteristic, which means that yield is controlled by hundreds of
genes located on the 42 chromosomes of wheat. The biggest problem is that these genes are
not mapped and that molecular markers, linked to these genes, are not regularly available.
A question frequently asked is: How much do genetics contribute to the improvement of
wheat and what is the rate of yield improvement? Pakendorf and Booyse (2012, personal
communication) showed a 0,75% genetic gain per year in wheat yields for the past 52 years in
South Africa, which compares favourably with the international trend of 0,5% - 1,5% genetic
gain per year in wheat yield.
However, it is suggested that a genetic gain of 10% - 15% is possible for wheat cultivars that
do not comply with current quality standards when cultivated under dryland conditions in
the Western Cape.
In order to keep up with the increasing demand for wheat and to make it economically viable
for producers to produce wheat, the primary aim of the ARC-Small Grain Institute (ARC-SGI)
Wheat Breeding Programme is to develop and release new and improved high yielding culti-
vars that are well-adapted to conditions in the Western Cape.
With that goal in mind, the ARC-SGI released Ratel in 2011. Ratel is a mid-season cultivar that
is well-adapted to conditions in the Rûens and Swartland. Yield data obtained from the
national small grain cultivar evaluation programme in the winter rainfall region showed that
Ratel had the third best yield over a four year period (2011- 2014) in the Rûens.
In addition to Ratel, the ARC-SGI already obtained preliminary classification for the line
(W12/12) and are very optimistic to obtain final classification approval early in 2016. The ARC-
SGI will immediately commence to commercialise this cultivar with the name Steenboks.
Steenboks is a short season cultivar that was developed specifically for the Swartland region.
Preliminary yield trials done in the Swartland showed that Steenboks performed extremely
well in the Piketberg and Philadelphia areas.
What is the future of wheat in the Western Cape?
The Western Cape is currently the bread basket of South Africa and will play an even more
important role in the future, due to a decline in wheat production in the north as a result of
drought and producers switching to more profitable cash crops. However, high input costs
and low wheat prices are some of the limiting factors that contribute to a reduction in wheat
production in the Western Cape.
It is therefore important to look at solutions that will make wheat production more profitable in
this region. One of the solutions is to release higher yielding wheat cultivars.
The ARC-SGI wheat breeding team in the Western Cape has committed
themselves to the release of high yielding cultivars and to play an important role
in saving the local wheat industry in the Western Cape and South Africa.