Effect of Headline Applications on Target Spot in Cotton

Extended periods of wet weather and high humidity often occur during the cotton growing season in Georgia. These conditions, especially in cotton fields with a dense canopy, can lead to development and spread of leaf spot diseases, such as Target Spot. Target Spot is caused by the pathogen Corynespora cassiicola and can lead to premature defoliation and potentially reduce yield.  An irrigated field study was conducted in two locations during the 2013 and one location in 2014 to determine the effect of Headline (pyraclostrobin) for the management of target spot. Treatments consisted of: season-long protection (where applications started at 1^st bloom and repeated every 2 weeks), applications made at the 1^st and 3^rdweeks of bloom, and beginning a fungicide treatment after the initial presence of disease. All Headline applications were made at 4 oz/A. Treatments were replicated three times and plots were arranged in a randomized complete block design. A disease assessment of all plots was recorded as percent leaf defoliation, taken three weeks before harvest. The 2014 trial revealed that fungicides may increase lint yield and overall plant health.