POSTERS: Chemical control
Evaluation of at-plant treatments for control of Rhizoctonia diseases of potato in Wisconsin
Afona Irabor - University of Wisconsin-Madison. Amanda Gevens- University of Wisconsin-Madison, John Hammel- University of Wisconsin-Madison, Stephen Jordan- University of Wisconsin-Madison
Field trials were conducted in 2017 and 2018 to evaluate seed- and in-furrow-applied fungicides for the control of Rhizoctonia seedling damping-off and tuber black scurf of potato at the University of Wisconsin Hancock Agricultural Research Station, WI. Cut and suberized ‘Russet Burbank’ seed pieces were planted in early May in each year. Plots were harvested, graded, and twenty tubers were randomly selected from each plot and visually evaluated for black scurf symptoms. There was high variability in results between the 2 years. Disease incidence in 2017 was less than that of 2018. In 2017, disease incidence for all treatments was not significantly different from the control. The seed-applied fungicides resulted in decreased emergence when compared to the non-treated control. In 2018, all seed-applied treatments resulted in significantly lower disease incidence on tubers when compared to the non-treated control. For the in-furrow-applied treatments, only Quadris 2.08SC, Vertisan EC1.67, Elatus 45WG, Priaxor 4.17SC and Regalia 5SC resulted in significantly lower disease incidence on tubers when compared to the non-treated control. Disease incidence with the biofungicide (Regalia 5SC) was not significantly different from that of the conventional fungicides. Despite the variability between years, results indicated that the seed-applied fungicides, Quadris 2.08SC, Vertisan EC1.67, Elatus 45WG, Priaxor 4.17SC and Regalia 5SC were effective against Rhizoctonia diseases of potato.