Timing of Application of Glyphosate to Maximize Sugar per Acre and Possible Alternatives to the Use of Glyphosate in Enhancing the Yield of Sugar of Louisiana Sugarcane in 2004

摘要

Etwo field experiments, the same chemical ripener treatments were applied to adjacent fields of CP 85-384 in the plant-cane crop on August 28 (Test I) and September 14 (Test II), 2004, in ater at a broadcast rate of 8 gal./A with a CO_2 sprayer and hand-held boom. The fields had been cultivated and fertilized according to recommended practices; insecticides were applied as required to control the sugarcane borer. Each experiment consisted of 14 treatments: Polado-L~(R) (glyphosate, N-(phosphonomethyl)glycine, in the form of its isopropylamine salt manufactured by Monsanto Technology LLC) at 4, 6 and 8 oz. of the formulated product per acre (0.1250, 0.1875 and 0.2500 lb. ae/A, respectively), Roundup WeatherMAX~(R) (glyphosate, N-(phosphonomethyl)glycine, in the form of its potassium salt manufactured by Monsanto Technology LLC) at 3.6,5.3 and 7.1 oz. of the formulated product per acre (0.1250, 0.1875 and 0.2500 lb. ae/A, respectively), Touchdown iQ~(R) (glyphosate, N-(phosphonomethyl)glycine, in theform of its diammonium salt manufactured by Syngenta) at 5.30, 6.65, 8.00 and 10.70 oz. of the formulated product per acre (0.1250, 0.1562, 0.1875 and 0.2500 lb. ae/A, respectively), Palisade~(R) (trinexapac-ethyl manufactured by Syngenta) at 0.223,0.267 and 0.312 lb. ai/A and an untreated check serving as a control. A nonionic surfactant, Induce~(R) (0.25% v/v)(Helena), was added to all spray solutions of Polado-L only. A 36-inch band was sprayed over sugarcane foliage so that most of the leaves werewet by the spray. Plots in each of the two experiments were one-row (6 ft.) by 50 ft. long with a 5-foot alley and with buffer rows on either side of treated row, arranged in a randomized complete block design with three replications. All plots of the two experiments were ultimately harvested green by combine at 56 days after treatment for both experiments. The mulch residue remained on the fields after harvest.