Take care with varieties: Roberts

WA growers have been urged to think particularly carefully about which grain varieties to retain for seeding in 2012.

Grains Research and Development Corporation western panel chairman Peter Roberts said seasonal conditions in 2011 had highlighted the susceptibility of some crop varieties to diseases, such as barley powdery mildew and rust, as well as quality issues like pre-harvest sprouting and low falling numbers.

"In addition to yield and time of seeding, it will be important for growers to consider disease resistance and grain quality when deciding which varieties to seed in 2012," Mr Roberts said.

Barley powdery mildew caused some epidemic losses in 2011, due to weather conditions, farmers growing susceptible varieties such as Baudin and the disease having developed resistance to triazole fungicides.

"If at all possible, growers should avoid the use of barley varieties rated susceptible or very susceptible in mildew-prone areas," Mr Roberts said.

He said the moderately resistant malting variety Buloke was a good alternative for growers wanting to minimise fungicide costs, if they lived in an area suited to this variety.

Seed for new barley varieties with levels of resistance to powdery mildew would also be available in limited amounts for the 2012 season.

Mr Roberts said growers who chose to retain susceptible varieties would need to use effective seed dressings such as Jockey at full rates and spray powdery mildew early with fungicides such as Opus, Opera, Amistar Xtra and Prosaro, which remained effective against the disease.

"Expect to use two or three sprays and use different fungicides each spray," he said. "Do not use tebuconazole to control mildew."

For more information about the susceptibility of barley varieties to powdery mildew, as well as rust, growers can access the Department of Agriculture and Food (DAFWA) bulletin Barley Variety Guide for WA 2012, available on the DAFWA website ( www.agric.wa.gov.au ) via the Bulletins link on the Publications tab.

Mr Roberts said growers should also be mindful of the susceptibility of cereal varieties to rust, following incidences of wheat stem rust and leaf rust in 2011, especially in central and southern grain growing areas.

More information about varietal resistance to rust are available in the Barley Variety Guide for WA, and the Wheat Variety Guide 2011, which will also be available on the DAFWA website, in the crops section.

As well, growers could access objective information about varieties, generated from GRDC-supported National Variety Trials, at www.nvtonline.com.au .

Mr Roberts said growers could also access these resources for information about varieties better able to withstand poor harvest weather, as experienced in 2011.

He said some cultivars of wheat and barley were particularly prone to pre-harvest sprouting and growers should assess the risks of keeping these varieties for future plantings.

"While no wheat varieties are resistant to sprouting, there is significant variation in their susceptibility to the problem, with traits such as head type and inherent falling numbers being important factors," Mr Roberts said.

"However, growers who have harvested grain affected by sprouting this year are urged to think twice before throwing out varieties which are otherwise well suited to their farming systems."

Growers should avoid the use of barley varieties rated susceptible or very susceptible in mildew-prone areas.

GRDC WESTERN PANEL CHAIRMAN PETER ROBERTS