Wheat Condition – Disease, Aphids
Rome recently wrote a good post on his blog about wheat conditions – it had some very good information.
Wheat is jointing well and some early planted early varieties even have a few flag leaves emerging. Powdery mildew disease is a concern but with warmer temperatures it usually calms down. We are watching for Stripe and Leaf rust now. Here’s an update from Extension Plant Pathologist Dr. Alfredo Martinez-Espinosa.“Powdery mildew (Blumeria graminis-Syn Erysiphe graminis) infections on wheatfields have been reported and confirmed recently across the state, especiallyon the southwest part of the state. Weather has been conducive for the disease.Powdery mildew tends to diminish as temperatures consistently reach above 75ºFand RH falls below 85%. If powdery mildew progresses up the plant and is foundin upper leaves (flag leaf minus 2) you might consider a fungicide application.”Aphids are still present in wheat fields but we are getting to a point in the season to where I’m not too worried about them. Also, we have lots of beneficial insects working on them pretty well. Decatur County Agent Justin Ballew and I found lots of syrphid fly larvae feeding on aphids yesterday as well as a few lady beetles and their larvae and lots of wasp parasitism by tiny wasps causing aphids to “blow up”.Here’s some wheat with some flag leaves emerging and a head or two.
Syrphid fly larvae chasing an aphid.
These aphids have blown up in size and are dead due to being parasitized by wasps.