The wheat crop is progressing about as well as could be expected in southwestern Arkansas despite the soggy field conditions. Prolonged wet field conditions have delayed some nitrogen top-dressing applications. However, most producers have finished spring nitrogen applications. Shortly after spring nitrogen applications, producers begin to scout their fields closely for signs of foliar diseases.
Currently no leaf rust has been reported in southwest Arkansas. Septoria, however, is being found on the lower leaves. Septoria is a fungus disease favored by cool, wet weather.
Fields should be checked every week from now until maturity. The progress of disease development can be tracked and better decisions can be made if and when a fungicide may be needed.
Rick Cartwright, Arkansas Extension plant pathologist, has reported the development of stripe rust in southern Texas and southern Louisiana. Strip rust can move very quickly. This situation will be monitored carefully over the next few weeks.
Almost 60 percent of the wheat acreage in southwest Arkansas has been planted in Coker 9663. This variety is susceptible to stripe rust, so if conditions become favorable for this disease, producers could be set up for a battle.
Arkansas Extension offices have a weekly disease report available to all growers, agribusiness and anyone else needing this information. These reports are being funded in part by the wheat producer checkoff program. The reports are updated each week with the latest field reports from all over the state. Predictions of disease development based on weather forecasts are made to help producers make better decisions about possible control strategies.
Yield potential, fertility levels, wheat variety, plant population and extended weather conditions all impact the level of disease severity and whether foliar fungicides may be needed.
Joe Vestal of Lewisville, Ark., is an Extension agent for Lafayette County, Ark.