Spring and Fall Supersweet Corn Trials in Georgia

In Spring and Fall of 2014 evaluations of supersweet corn varieties were conducted in Attapulgus and Tifton, Georgia, respectively. In spring and fall there were 29 and 27 varieties of bicolor, yellow and white corn evaluated, respectively.   Trials were planted on 24 Mar. and 12 Aug. 2014 and managed using standard practices recommended by The University of Georgia.  Plant populations were 64,555 per hectare. Emergence, vigor, yield, average ear length and width, row of kernels, tip coverage and tillers were recorded. There were significant differences in seed emergence and plant vigor in the spring-planted trial with five varieties having emergence rates below 90%. Emergence and plant vigor were well correlated. All varieties had high emergence and vigor ratings for the fall trial. The highest yielding varieties in spring were 2974 MXR, Awesome XR and BSS 0977, and the lowest were Obsession II, SC 1336, and 2760 MR.  The highest yielding varieties in the fall were Obsession SC 1336, 1229, and 7143, and the lowest were Obsession II, Stellar XR and 3188 MR.  In the fall, even the lowest yielding varieties had yields that were comparable to some of the higher yielding varieties in the spring. Yields in the fall averaged 150-200 more boxes per ha than in spring.  There were significant differences in ear length and width.  Ear length on average for all varieties was greater in spring and ranged from 18.3 to 21.6 cm and 16.5 to 20.5 cm in fall. Conversely, ear width ranged was slightly, but significantly lower in spring than in fall.  Ear width ranged from 4.0 to 5.1 cm in spring and 4.6 cm to 5.4 cm in fall.  Kernel rows were variable and not significantly different among seasons, although were different among varieties.  Lodging was not observed in the spring trial; however, four varieties, Bright White, Rainier, Stellar XR, CAPBF10-411, and 2974 MCR had lodging rates of greater than 25%.  Significant differences were observed for quality and yield for varieties in spring and fall, suggesting that supersweet corn trials for the Southeastern U.S. should be conducted during both growing seasons to make scientifically based recommendations to growers.