We have just gotten test results back from Tifton confirming a case of Target Spot in western Dooly Co. In this particular situation the disease is not widespread and is not causing severe defoliation(probably due to the drier weather and sound management practices) and Dr. Kemerait is not recommending a spray on this field. I am including another link to the Target Spot Index here.
According to Dr. Kemerait –
If the cotton is less than 15 percent defoliated, and the crop is within the first four to six weeks of bloom, there is still time to spray. We should also be four to six weeks away from defoliation.
At this stage in the season, you should be scouting for Target Spot, especially in fields that have not had timely PGR applications. If you think that you have found Target Spot, please bring affected leaves to the Dooly County Extension office so that we can help confirm the disease for you and help you make a decision for fungicide application .