Efficacy of new fungicides and Captan cover sprays for control of brown rot of peach in middle Georgia, 2018

Authors: BRANNEN, PHILLIP - University Of Georgia; BALDINO, K - University Of Georgia; WILLIAMSON, Z - University Of Georgia; Bock, Clive; Stokes, Unicka; Hotchkiss, Michael - Mike

Submitted to: Plant Disease Management Reports
Publication Type: Other
Publication Acceptance Date: 6/10/2019
Publication Date: 7/1/2019
Citation: Brannen, .M., Baldino, K., Williamson, Z., Bock, C.H., Stokes, U.L., Hotchkiss, M.W. 2019. Efficacy of new fungicides and Captan cover sprays for control of brown rot of peach in middle Georgia, 2018. Plant Disease Management Reports. 13:PF034.

Interpretive Summary: Fungicides were evaluated for control of brown rot in an experimental peach block located at Byron, GA. Treatments were applied with an airblast sprayer (100 gal/A spray volume) and included an untreated control, Pristine (boscalid + pyraclostrobin) as the chemical standard, Experimental 1, Experimental 2, Luna Sensation (fluopyram + trifloxystrobin), Captan cover sprays, and Captan cover sprays follow by Merivon (fluxapyroxad + pyraclostrobin). At full maturity, 32 asymptomatic fruit were harvested from each lot for rot assessments. Fruit were placed on plastic produce trays and stored at ambient room temperature (air-conditioned room; ~77 F). Rot incidence was recorded at five and eight days after harvest (DAH). Brown rot disease was severe in this trial. At the first rating, all treatments provided suppression of brown rot, but disease was rampant. By the second rating, no treatment provided significant control. Of interest, the Captan 4L cover sprays did provide significant disease suppression at the first rating as well, even under the heavy pressure of this trial. This lingering suppression of brown rot by Captan cover sprays has been reported elsewhere, but it is interesting to see that it was observed even under these conditions.

Technical Abstract: Fungicides were evaluated for control of brown rot in an experimental peach block located at Byron, GA. Treatments included an untreated control, Pristine (boscalid + pyraclostrobin) as the chemical standard, Experimental 1, Experimental 2, Luna Sensation (fluopyram + trifloxystrobin), Captan cover sprays, and Captan cover sprays follow by Merivon (fluxapyroxad + pyraclostrobin). At full maturity, 32 asymptomatic fruit were harvested from each lot for rot assessments. Rot incidence was recorded at five and eight days after harvest (DAH). Brown rot disease was severe in this trial. At the first rating, all treatments provided suppression of brown rot, but disease was rampant. By the second rating, no treatment provided significant control. Of interest, the Captan 4L cover sprays did provide significant disease suppression at the first rating as well, even under the heavy pressure of this trial. This lingering suppression of brown rot by Captan cover sprays has been reported elsewhere, but it is interesting to see that it was observed even under these conditions.