A ProMED-mail post
<http://www.promedmail.org>
ProMED-mail is a program of the
International Society for Infectious Diseases <http://www.isid.org>
Date: Thu 13 Aug 2009
Source: Weekly Times [edited]
<http://www.weeklytimesnow.com.au/article/2009/08/13/101631_on-farm.html>
Grain growers are being urged to check wheat crops after reports
of Victoria's 1st stripe rust outbreak this season [2009]. The
Department of Primary Industries [DPI] senior plant pathologist
Dr Grant Hollaway said the outbreaks, in the Mallee [low
rainfall area with small trees and shrub vegetation], were not
unexpected, following reports of the disease in Queensland and
northern New South Wales [ProMED-mail post 20090312.1019].
This season's [2009] early break and sowing of crops, coupled
with wetter seasonal conditions had been favourable for rust
development, Dr Hollaway said. Croppers need to begin checking
their paddocks and be ready to spray if necessary. The disease
is better managed by applying fungicides early in the epidemic
rather than later.
Last season [2008], stripe rust was detected in [Victoria]
regions at tillering [ProMED-mail post 20080916.2897] and a
spray was required in many varieties to protect green leaf area
until the onset of adult plant resistance, which starts around
ear emergence in certain varieties.
--
communicated by:
George A Robertson, PhD
Senior Technical Advisor
Vaccine Development Global Program
Washington, DC 20006
USA
<grobertson@path.org>
[Stripe rust, also called yellow rust, of cereals is caused by
the fungus _Puccinia striiformis_ var. _striiformis_. It causes
yellow leaf stripes and stunting of plants with yield losses of
40 to 100 per cent. It affects wheat, some barley varieties,
triticale, and a number of wild grasses.
Spores are wind dispersed in several cycles during the cropping
season.
Grasses and volunteer crop plants may generate a "green bridge"
providing inoculum for the next crop. Disease management
includes the use of resistant varieties, fungicide applications,
and control of volunteer crops.
New stripe rust strains with increased virulence have been
reported in recent years from Europe, North America, Australia,
India, and are also suspected to have emerged in China. Disease
monitoring is important to recognise new pathogen strains, and
continuous resistance breeding is required to keep ahead of
pathogen adaptation.
In Australia, stripe rust outbreaks were reported in 2008 in
several states, which may have increased the available inoculum
for the current crops. Earlier in 2009, the disease was reported
for flood-affected northern New South Wales and the Esperance
region of Western Australia, and an alert was issued for the
2009 South Australian broadacre crops due to the risk of
interstate spread.
Maps of Australia:
<http://www.ga.gov.au/image_cache/GA4073.jpg>
and <http://healthmap.org/r/00cS>
Pictures Stripe rust on wheat leaf:
<http://utextension.tennessee.edu/fieldCrops/wheat/Wheat_photos/Wheat_StripeRust.jpg>
and
<http://www.grdc.com.au/uploads/images/Stripe%20rust%20Colin%20Wellings%20ACRCP.JPG>
Stripe rust on wheat head:
<http://gallery.cimmyt.org/main.php?g2_itemId=296>
Stripe rust on resistant and susceptible wheat cultivars:
<http://www.oznet.ksu.edu/path-ext/factSheets/wheat/Wheatimages/wheats1.jpg>
Links
DPI Victoria press release:
<http://new.dpi.vic.gov.au/about-us/news-and-events/news/media-releases/media-releases-from-ministers/seasons-first-stripe-rust-found-in-mallee-wheat>
Information on wheat stripe rust:
<http://www.ars.usda.gov/Main/docs.htm?docid=9918&pf=1&cg_id=0>,
<http://www.dpi.nsw.gov.au/__data/assets/pdf_file/0006/158964/stripe-rust-in-wheat.pdf>,
<http://pnw-ag.wsu.edu/smallgrains/Stripe%20Rust.html>, and <http://www.oznet.k-state.edu/path-ext/factSheets/Wheat/Wheat%20Stripe%20Rust.asp>
Stripe rust management:
<http://www.grdc.com.au/uploads/documents/striperustmgt.pdf>
and <http://www.ipm.ucdavis.edu/PMG/r730100511.html>
_P. striiformis_ taxonomy:
<http://www.indexfungorum.org/Names/NamesRecord.asp?RecordID=427989>
. - Mod.DHA][see also
in the
archive:
Stripe rust, wheat - Canada: (AB) alert 20090724.2614 Fungal
diseases, cereal crops - China, Ireland 20090528.1983 Stripe
rust, wheat - UK (02): new strain 20090514.1806 Rust diseases,
wheat - UK, Pakistan 20090424.1543 Stripe rust, wheat - UK
20090417.1452 Stripe rust, wheat - India: new strain
20090329.1216 Wheat rusts - Kenya, India, Australia
20090312.1019 Rust diseases, wheat, mustard - India: (JK)
20090305.0897 Stripe rust, wheat - China 20090208.0579
2008
---
Stripe rust, wheat - Australia (02): (VIC) 20080916.2897 Stripe
rust, wheat - Australia: (QLD, NSW), alert 20080716.2156 Cereal
rusts - Australia: (NSW) 20080624.1945 Wheat stripe rust,
oilseed rape sclerotinia - China 20080408.1297 Stripe rust,
wheat - Denmark: new strains 20080211.0542
2007
---
Stripe rust, wheat - Australia (SA): new strain 20070921.3135
Stripe rust, wheat & wheat streak mosaic - Australia (SA, WA)
20070830.2860 Fungal diseases, wheat & pulses - Australia (SA)
20070821.2729 Ergot & stripe rust, cereals - USA (MT)
20070706.2144 Stripe rust, wheat - USA, Australia 20070614.1950
Wheat stripe rust, wheat - China 20070413.1230 and older items
in the archives] |
|
Stripe Rust Advice |
|
Victorian grain growers are
reminded of the availability of
a comprehensive central
information resource to assist
them in management of cereal
rust this season. Following the
first stripe rust outbreak for
the season, growers are
encouraged to access valuable
information from the
Grains Research and Development
Corporation’s (GRDC) online
service at
www.grdc.com.au/rustlinks.
Department of Primary Industries
Senior Plant Pathologist, Dr
Grant Hollaway, said the
outbreaks had occurred in the
Mallee and were not unexpected,
given the favourable conditions
and reports of the disease in
Queensland and northern New
South Wales. Dr Hollaway said
growers should now begin
checking paddocks and be
prepared to spray if necessary
because the disease was better
managed by applying fungicides
early in the epidemic rather
than later.
“In previous years, dry springs
have minimised the stripe rust
development, but with wetter
condition this season, farmers
will need to be vigilant to
ensure their crops are
protected,” Dr Hollaway said.
The GRDC financially supports
research into rust management
through the Australian Cereal
Rust Control Program. |
|
