Kenneth Gravois | 8/11/2016 6:14:00 PM
The outfield variety trials are the final stage of testing of experimental varieties for their potential commercial production in Louisiana. Results from these trials are used in both variety advancement and crossing decisions. The outfield variety trials are cooperatively conducted at 12 locations throughout the Louisiana sugarcane belt by the LSU AgCenter, the USDA-ARS and the American Sugar Cane League.
The experimental design at each outfield location was a randomized complete block design with three replications per location. Test plots were two rows wide and 50 feet long with a 5-foot alley between plots. All locations were harvested with a combine harvester, and each plot was weighed with a weigh wagon fitted with load cells mounted on each axle and hitch. Cane yield (tons/acre) for each plot was estimated from the plot weight, less 14% to adjust for leaf-trash weight and 10% for harvester efficiency. A hand-cut 10-stalk sample, not stripped of leaves, was taken from each plot and sent to the USDA-ARS sucrose laboratory for analyses. The samples were weighed to determine stalk weight (lbs/stalk) and milled, and the juice was analyzed for Brix and pol. Brix and pol values were used to estimate pounds of theoretical recoverable sugar per ton of cane (lbs/ton). Stalk number (stalks/acre) was calculated by dividing adjusted cane yield by stalk weight.
The most widely grown variety for that crop year is highlighted in gray and serves as a standard for variety comparisons. To adjust for missing data, the SAS analysis calculated least square means (Proc Mixed). Mean separation used least square mean probability differences (P=0.05). Varieties that are significantly higher or lower than the check variety were denoted by a plus (+) or minus (-), respectively, next to the value for each trait.