Peach Brown Rot Fungicides Trial, 1987 



Daniel Cooley and James Mussoni 



Department of Plant Pathology, University of Massachusetts 



Joseph Sincuk 



Department of Plant & Soil Sciences, University of Massachusetts 



Two of the newer fungicides for peach brown rot Funginex 1.6 EC was used in 1 treatment at the lower 



control are Ronilan^^ (vinclozolin) and Rovral^^ (iprodi- end of the standard rate range (12 oz/100 gal), Rovral 



one). These materials are reported to be more effective 50WP was used at 0.25 Ib/lOO gal (1/2 the standard rate) 



than most other fungicides on peach brown rot. However, and Ronilan 50 WP was used in 3 treatments at 0.75 lbs, 0.75 



they are also more expensive than other materials. lbs plus the spray adjuvant X-77™, and at 0.5 lbs plusX-77 



Ronilan and Rovral are labelled and recommended (standard rate for Ronilan is 1 lb/100 gal). Treatments 

 such that a lower rate may be used under low or moderate were scheduled at the discretion of the assistant orchard 

 brown rot pressure. That means that when the weather is manager, and were done on the following dates under the 

 relatively dry, then the lower rate may be used. We tested weather conditions listed: May 11-late petal fall (70°F, 

 these materials at the lower label rates (and in one case, light breeze); May 26--post shuck split (85°F, light breeze); 

 below the lowest label rate) in 1987, to see whether or not June 22--ripening fruit (85°F, humid, shower); July 6--not 

 the low rates would perform as well as a low rate of Harbinger (75°F, clear, calm); and August 5--Glo Haven 

 Funginex^^ (triforine), which has been an effective mate- only (80°F, clear, calm). Sprays were applied with a high- 

 rial against brown rot for a number of years. We examined pressure handgun sprayer at a rate of 250 gal per acre, and 

 the efficacy of the lower rates and analyzed it with respect trees were sprayed to the drip point, 

 to the costs. The block consisted of three cultivars: Harbinger, 



8 



