Grains Research and Development

Date: 01.06.1999

1999 Key Disease Threats

Comic

1998 NORTHERN WINTER CROPS One-in-a-hundred-year outbreak of yellow spot — costing the industry some $200 m and leaving a legacy of high levels of inoculum in paddocks - a danger for 1999 winter crops.

Northern region

Major northern region disease threats this year are expected to be yellow spot, crown rot and net blotches.

Wheat

  • Yellow spot - Average Annual Loss $2.7m
  • Leaf rust - Average Annual Loss $0.9m
  • Stem rust - Average Annual Loss $0.2m
  • Stripe rust - Average Annual Loss $0.6m
  • Black point - Average Annual Loss $4.5m
  • Crown rot - Average Annual Loss $21.3m
  • Root lesion nematode (Pratylenchus thornei) - Average Annual Loss $33.3m
  • Common root rot - Average Annual Loss $9.2m

Barley

  • Net blotch (net form and spot form) Spot blotch Black point Leaf rust Powdery mildew
  • Scald (more likely to be a problem in the southern part of the region) Crown rot Common root rot

Western region

With a relatively early, wet start, the western region will be at risk from leaf diseases this year. Major disease threats are expected to be wheat Septoria nodorum blotch and yellow spot (these often occur together), wheat leaf rust, and barley yellow dwarf virus in wheat and barley.

Wheat

  • Yellow spot - Average Annual Loss $43.2m
  • Leaf rust - Average Annual Loss $6.0m
  • Stem rust - Average Annual Loss $1.2m
  • Septoria nodorum blotch - Average Annual Loss $56.9m
  • Septoria tritici blotch - Average Annual Loss $15.1m
  • Crown rot - Average Annual Loss $0.4m
  • Root lesion nematode (Pratylenchus neglectus) - Average Annual Loss $3.7m
  • Barely yellow dwarf virus (in high-rainfall areas) - Average Annual Loss $2.1m
  • Take-all - Average Annual Loss $5.6m
  • Rhizoctonia bare patch - Average Annual Loss $0.4m

Barley

  • Net blotch (net form and spot form) Scald
  • Barley yellow dwarf virus (in high-rainfall areas)
  • Rhizoctonia bare patch
  • Root lesion nematode (Pratylenchus neglectus and other species)
  • Take-all

Southern region

Major southern region disease threats this year are expected to be Pratylenchus (both types), possibly take-all, and possibly yellow spot, in wheat; net blotch in barley.

Wheat

  • Yellow spot - Average Annual Loss $3.2m
  • Leaf rust - Average Annual Loss $2.6m
  • Stem rust - Average Annual Loss $0.2m
  • Stripe rust - Average Annual Loss $10.5m
  • Barley yellow dwarf virus - Average Annual Loss $6.4m
  • Crown rot - Average Annual Loss $34.7m
  • Root lesion nematode - Average Annual Loss $9.2m
  • Common root rot - Average Annual Loss $12.2m
  • Cereal cyst nematode - Average Annual Loss $36.0m
  • Septoria tritici - Average Annual Loss $13.2m
  • Rhizoctonia - Average Annual Loss $31.1m
  • Take-all - Average Annual Loss $46.3m

Barley

  • Barley yellow dwarf virus (in high-rainfall areas)
  • Net blotch (net form and spot form) Scald
  • Rhizoctonia
  • Cereal cyst nematode
  • Common root rot

Region North, South, West