Performance of Selected Insescticides Against Soybean Looper in Soybean 2, 2019

The performance of selected foliar insecticide treatments against soybean looper infestations in soybean was evaluated at the Delta Research and Extension Center (Washington County). Soybean seeds (Asgrow 45X8) were planted on a Bosket very fine sandy loam soil on 13 June at a seeding rate of 117,612 seed/acre. Plot size was four rows (40 in centers) by 40 feet. Treatments were replicated four times in an RCB. Foliar insecticide treatments were applied on 27 August with a high-clearance sprayer with a compressed air spray system calibrated to deliver 10 gpa through TX-6 hollow cone nozzles (2/row) at 3.5 mph. Soybean looper densities were determined by sampling one of the center two rows with a 15-in.-diameter sweep net. A sample consisted of 25 sweeps per plot. Plots were sampled at 3 and 7 d after treatment (DAT). The same row in each plot was not sampled on consecutive sample dates. Data were subjected to ANOVA, and means separated according to Fisher’s protected least significant difference.

At 3 DAT all of the insecticides, except Besiege (both rates) and Intrepid, reduced soybean looper densities compared with the untreated check (Table 1). Also Intrepid Edge resulted in fewer soybean looper larvae than Besiege (both rates), and Intrepid. At 7 DAT all of the insecticides reduced looper densities compared with the untreated check. Also plots treated with Intrepid Edge had fewer loopers than plots treated with Besiege (7 oz) or Intrepid.¹

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