Efficacy of Aerial Application of Selected Insecticides Against Sugarcane Borer, 1993

Six insecticide treatments were tested for season-long control of SCB at Blackberry Farm, located in Vacherie, LA. A RCBD (4 reps) which incorporated 28 plots of SBC-susceptible plant cane was utilized. Plot size ranged from 0.37 to 0.92 ha (avg 0.67 ha). Each treatment was applied in water using a Cessna Ag Cat with swaths of 14.5 m (8 rows) delivering 18.7 liters of finished formulation per hectare. The plots were treated on 12 Aug when 5% of sugarcane stalks contained live larvae (3rd instars or smaller) in the leaf sheaths. Mortality (live/dead) was assessed 3 DAT by collecting and identifying stage of 15-20 larvae/plot. To determine the length of control, and if additional applications were needed, weekly infestation counts were made in each plot after the application. YSA infestations also were monitored weekly by counting the number of YSA on the 3rd or 4th leaf below the whorl of 20 randomlyselected plants. SCB infestations remained below economic injury for the remainder of the growing season and therefore no other applications were made. SCB damage was assessed by counting the number of bored internodes, exit holes, and the total number of internodes of 75 sugarcane stalks per plot (5 sites/plot, 15 stalks/site) on 5 and 7 Oct. Separation of means was by LSD.