CSIRO research team uses barley to boost wheat vigour
CROP DOCTOR: By Peter Reading, managing director of the Grains Research and Development Corporation
Increasing the vigour of cereal crops can lead to more efficient water use and increased grain yields.
It can also reduce weeds and increase nutrient uptake.
Dr Richard Richards is leader of the CSIRO’s High Performance Crops Program. His focus is on breeding higher yielding wheat and gaining a better understanding of the genetic variations in wheat growth, development and yield.
His team has produced unique wheat plants by combining different traits that control vigour, from varieties found in Australia and around the world.
Speaking on the GRDC’s latest Driving Agronomy 2010 audio compact disc for the southern region, Dr Richards believes these super vigorous wheats are different to other varieties anywhere else in the world and have deeper, more extensive root systems and more extensive branching. The key to unlocking this new vigour in wheat actually came from barley.
Dr Richards observed barley growing side by side with wheat and noted barley was more vigorous with extra tillers and was better yielding than wheat in dry environments.
The team worked out how barley achieved its higher vigour and then set about recreating that in wheat.
Dr Richards says crop vigour is important in making best use of rainfall. In many years in southern Australia, only half of the rainfall received in the growing season is used by the crop, meaning the other half is wasted. His focus has been on increasing crop vigour to ensure more rainfall is used by the plant and less evaporates from the soil surface.
He says it is a balancing act to choose the right variety of wheat for the range of climate conditions possible during a growing season.
In dry years, the super vigorous wheats under development could yield less than current conventional varieties if sown in mid May. But if sown later, they are likely to yield better than current varieties.
However in average rainfall years, the super vigorous wheats are expected to perform better than current varieties.
The CSIRO team has also been working on wheats that do not require as much phosphorus, and is leading the world with its results.
Dr Richards says there are two mechanisms in varieties for improving P use efficiency. However, they are not currently found in any of the wheats grown in Australia.
The key is in developing wheats with these mechanisms so they can solubilise the large bank of soil P that is currently unavailable to plants.
GRDC’s supplements Agronomy and Wheat Breeding are free and can be downloaded from GRDC’s website, www.grdc.com.au, or ordered from Ground Cover Direct, freecall 1800 110044 or email ground-cover-direct@canprint.com.au. A GRDC Driving Agronomy 2010 audio compact disc for the southern region is available free (plus postage and handling) through GRDC’s Ground Cover Direct. Order code is GRDC474.
