|ISAKEIT, THOMAS - TEXAS A&M UNIVERSITY|
|JANAK, TRAVIS - B-H GENETICS|
|GRICHAR, JAMES - B-H GENETICS|
Submitted to: Plant Disease Management Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/6/2017
Publication Date: 3/7/2017
Citation: Isakeit, T., Prom, L.K., Janak, T., Grichar, J. 2017. Effect of fungicides on anthracnose and grain mold of sorghum in Wharton County, Texas, 2016. Plant Disease Management Reports. 11:FC022.
Interpretive Summary: Anthracnose and grain mold of sorghum are two important diseases that can reduce yield and seed quality. This study identified two fungicides Priaxor and Headline that significantly reduced the level of anthracnose on the hybrid BH 5566, especially on the panicles later in the season. None of the fungicides tested in this study reduces the level of grain mold infection. This work is significant because it has identified fungicides capable of reducing the effect of sorghum anthracnose on both the leaves and panicles and that can be utilized by growers in the USA to control the disease.
Technical Abstract: The experiment was conducted in Wharton County, Texas using the hybrid BH 5566. There were four replicates per treatment arranged in a randomized, blocked factorial design. Each replicate consisted of four, 20.5-ft rows, with 38-in. row spacing and a plant spacing of 1.9 in. within rows. Three fungicides Headline, Quilt Xcel, and Priaxor were applied at full bloom to the middle two rows with a CO2-pressurized backpack sprayer, at 22 psi in a spray volume of 10 gal/A, using four TeeJet XR8002VS flat fan tips spaced 19 in. apart. Plots were evaluated for foliar disease in June and July by estimating percent lesioned area on the leaves. To assess grain mold, three panicles were harvested from each replicate and threshed. The three sub-samples of each replicate were assessed for grain mold using a 1-5 scale. Subsequently, 100 seed from each sub-sample were weighed and then incubated one week on germination paper. All fungicide treatments had less anthracnose than the control at 27 days after application, but only Priaxor and Headline had less anthracnose than the control at 45 days after application. These two fungicides also had significantly less panicle blight than the control. However, there was no effect of any of the fungicide treatments on yield, although the yield of the Priaxor treatment was greater than that of the control. None of the fungicide treatments had any effect on grain mold severity, seed weight or germination.