The objective of this study has been to determine vitamin C content in tubers of edible potato following an application of systemic insecticides to control the Colorado potato beetle.
A field experiment was conducted on soil of a good rye complex in 2004-06. The experiment was designed as randomized sub-blocks with three replications. Experimental factors included three cultivars of potato – Wiking, Mors, Żagiel – and six Colorado potato beetle control treatments using the following insecticides: Actara 25 WG (thiametoksam) at the rate of 0.08 kg/ha, Regent 200 SC (fipronil) at the rate of 0.1 dm3/ha, Calypso 480 SC (thiacloprid) at three rates (0.05, 0.075, 0.1 dm3/ha), and a control treatment without chemical protection. The content of vitamin C was dependant on cultivar, insecticide treatment, and environmental conditions with each year. The insecticides applied significantly increased vitamin C content (amounted to 1.7 mg/kg) compared with the tubers harvested from the control treatment where no chemical protection was applied. Tubers of Mors cultivar had the highest vitamin C content, and Wiking cultivar lowest.