Evaluation of fungicides for control of common rust of sweet corn on a resistant and a susceptible cultivar, 2007

摘要

Sweet corn seed of both varieties were planted on 2 Apr at the University of Georgia’s branch research station in Attapulgus Georgia. Seed were planted every 8 in. in rows spaced 36 in. apart. The experiment utilized two row, split plotswith the main block being fungicide treatment and the subplot being corn variety. These split plots were arranged in a randomized complete block design with 4 replications. Fungicide plots were 30-ft long with a 5-ft buffer between replications. Fungicides were applied using Lee Spray Trac~R calibrated to deliver 15 gal/A at 40 psi through 8002 hollow cone nozzles. Treatments were initiated at late whorl stage on 29 May and were sprayed twice more on 5 and 12 Jun. Once disease was observed, microscopicexamination of the pustules indicated the presence of urediniospores of Pucciniua sorghi. Standard practices for management of irrigation, weeds, nematodes and insects for sweet corn grown in Georgia were followed throughout the season.