Effects on Non-Target Arthropods from Sugarcane Borer Control Large Plot Field Trial, 1992:

Abstract

Insecticide sprays were applied 2 times to sugarcane fields located at Palo Alto Plantation near Donaldsonville, LA, to evaluate effects of full-season control of sugarcane borer infestations on non-target arthropods. Treatments were assigned to individual plots (ca. 1.5 ha each) according to a randomized complete block design with 4 replications. Spray concentrates were applied by aircraft on a 14.5 m swath in water at a rate of 18.7 liter finished formulation/ha/application (2 gal/acre). The number and size of nozzles, the density (drops/cm), and size (μ) of droplets for the water mixed sprays were 29, 8046, 23.5, and 250, respectively. Insecticide applications were initiated on 28 Jul, when sugarcane internodes were visible above ground and at least 5% of the stalks harbored 1st to 3rd stage larvae in the leafsheaths. A second application to all treatments was made on 16 Aug when that threshold level of infestation again was found in plots treated with Asana XL. Non-target arthropods were continuously monitored in all treatments throughout the study using pitfall traps (pint jars filled with 150 ml of 70% methanol and 25 ml of mineral oil) embedded on the row and covered by a 22 cm diam disc supported by a tripod 3 cm above the jar and soil surface. Two traps were situated centrally 22 m apart in each plot and changed biweekly from 30 Jul to 21 Sep.