Sydney, Australia
August 17, 2015
Source
PROFESSOR ROBERT PARK & DR DAVINDER SINGH
The University of Sydney, Plant Breeding Institute, Cobbitty
Email: robert.park@sydney.edu.au Phone: 02-9351 8806
DR WILLIAM CUDDY
Co-located at the NSW Department of Primary Industries, Elizabeth Macarthur Agricultural Institute, Menangle and
The University of Sydney, Plant Breeding Institute, Cobbitty
Email: will.cuddy@dpi.nsw.gov.au Phone: 02-9351 8871
In our last report, we provided information on current distributions of wheat leaf rust, oat stem rust and oat crown rust. This follow-up report summarises pathotype (pt.) assay results from the samples that have been processed to date. Of note is the recovery of wheat leaf rust pt. 104-1,3,4,6,7,8,9,10,12 +Lr37 from Victoria and South Australia. This pathotype was first detected last year, in SA, and is considered to be of exotic origin. With rusts now being reported from around the country, we encourage you all to collect and send samples to us for pathotype analyses. The practice of artificially inoculating nurseries with rust now appears to be commonplace in many regions; if samples are forwarded from these nurseries, we request that they be identified as such.
Wheat stripe rust
As reported earlier, the first samples of wheat stripe rust were received on the 7th August from Goondiwindi and Westmar in Queensland. The disease was subsequently reported on 11th August from Wagga Wagga. Pathotype tests are underway on these samples.
Wheat leaf rust
Ten samples of leaf rust on wheat have been received to date, of which 7 have been processed.
A sample from Lake Grace in WA off Yitpi (2nd July) was identified as pt. 76-1,3,5,7,9,10,12 +Lr37. This pathotype was first detected in WA in October 2013. The varieties Corack, Emu Rock, Mace and Wyalkatchem are all expected to be more susceptible to this pathotype than to those that prevailed prior to its detection in 2013. Growers of these varieties in particular are encouraged to monitor crops closely for leaf rust.
Two samples from Queensland, Warwick (21st May) and Cleveland (21st May) comprised three pathotypes related to the one detected in WA, viz. 76-3,5,7,9,10,12,13 +Lr37; 76-1,3,5,7,9,10,11,12,13 +Lr37; 104-1,3,5,7,9,10,11,12 +Lr37. A sample from northern NSW (Grafton, collected 1st July) was also identified as pt. 104-1,3,5,7,9,10,12 +Lr37.
A single sample from SA (Bool Lagoon, 22nd July) and two samples from Victoria (Inverleigh, 2nd July; Derrinallum, 9th July) were all identified as pt. 104-1,3,4,6,7,8,9,10,12 +Lr37. This pathotype was detected for the first time in August last year (Bool Lagoon SA), and is considered to be of exotic origin.
Many wheat varieties have been given provisional ratings of higher susceptibility in 2015 variety guides pending further data on their responses to the pathotypes detected in eastern Australia, in particular, pt. 104-1,3,4,6,7,8,9,10,12 +Lr37. Those to watch include: Axe, Baxter, Bolac, Chara, CLF Janz, Corak, Correll, Cosmick, Crusader, Dart, Emu Rock, Grenade CL PLUS, Impala, Justica CL PLUS, Mackellar, Preston, SF Scenario, SQP Revenue, Spitfire, Sunvale, Viking and Wallup.
Barley leaf rust
A single sample of leaf rusted Bass barley from Manjimup (22nd July) was identified as pt. 5457 P-. This pathotype was first detected in WA in September 2013. It is virulent for the resistance gene Rph3, present in the varieties Bass, Granger and Oxford, the latter two having additional adult plant resistance provided by gene Rph20.
Oat crown rust and oat stem rust
Five samples of oat crown rust have been received from Queensland, all of which have been processed. Six pathotypes were identified, one or more of which were virulent on the varieties Drover, Warrego and Volta. While virulence on Aladdin was detected for the first time in 2014 (Queensland), it has not yet been detected in 2015. All oat varieties are susceptible to at least one of the crown rust pathotypes that have been detected in Australia in recent years.
Two samples of oat stem rust have been processed to date: one from Queensland (Wellcamp, 5th June) and Kingsthorpe (1st July), both comprising pathotype 41-1,4. As is the case with crown rust, all oat varieties are susceptible to at least one of the stem rust pathotypes that have been detected in Australia in recent years.
Reply Paid envelopes now available for free
To make it easier to submit samples to the Australian Rust Survey, reply paid envelopes are now available. If you would like to receive a supply of free envelopes, please contact Will Cuddy. Alternatively, the reply paid details at the bottom of this report can be used on any envelope to post a sample to the survey.
Topics
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