Bill Cissel, Extension Agent – Integrated Pest Management; bcissel@udel.edu
Congratulations to Mark Sultenfuss for identifying the disease as Barley Yellow Dwarf and for being selected to be entered into the end of season raffle for $100 not once but five times. Everyone else who guessed correctly will also have their name entered into the raffle. Click on the Guess the Pest logo below to participate in this week’s Guess the Pest! For Guess the Pest # 4, we will also be giving away A Farmer’s Guide To Corn Diseases ($29.95 value) to one lucky participant.
http://www.plantmanagementnetwork.org/book/cornfarmersguide/
Guess the Pest #3
Barley Yellow Dwarf (BYD) is vectored by aphids and is considered the most widespread viral disease of economically important grasses worldwide. Symptoms of BYD include discoloration of the leaves and in some cases, stunting of the plant. In wheat, the leaves often appear yellow to purple in color and in barley, the leaves are typically yellow. In severe cases, stunting can occur and grain heads can fail to emerge. In other severe cases, grain heads contain dark and shriveled seed. In Delaware, BYD is often observed in patches, 1-5 ft in diameter. The severity of symptoms is influenced by the strain of the virus (different strains are vectored by different aphid species), the timing of infection (fall infections are typically more severe than spring), and a variety’s tolerance to BYD. Symptoms of BYD can be confused with other issues such as nutrient deficiencies or compaction. A diagnosis cannot be based on symptoms alone and samples must be submitted to a diagnostic lab for conformation.
Here is a link to Agdia if you would like to submit a sample for BYD screening:
http://www.agdia.com/
Management of BYD involves an integrated approach including planting date, alternate host management, variety selection, and chemical control to manage aphids.
For more information on Barley Yellow Dwarf and potential management options, please visit our Fact Sheet:
https://cdn.extension.udel.edu/wp-content/uploads/2015/10/14051904/BYDV-Final-Draft-9-12-16.pdf
Here is a link to view additional images of BYD symptoms: https://www.flickr.com/photos/139973317@N03/sets/72157666301880210/
Images of Common Aphid Species infesting small grains:
https://www.flickr.com/photos/139973317@N03/sets/72157664513242564/
Youtube Video demonstrating how to scout small grains for aphids in the fall:
https://www.youtube.com/watch?v=He3nTpL6k_U&nohtml5=False
Guess the Pest #4
What is this barley disease? Think you know the answer…. Click on the Guess the Pest Icon below or go to https://goo.gl/forms/pWjHQUpmjABFB0v32 to submit your best guess.
Think you know the answer…. Click on the “Guess the Pest” logo to submit your guess.
