Efficacy of Selected Insecticide Seed Treatments against Sugarcane Beetle in Field Corn, 2013 * Open Access

On 13 May 2013, an insecticide seed treatment trial was initiated on the R.R. Foil Plant Science Research Center in Starkville, MS. Nine insecticidal seed treatments were evaluated against an untreated check (UTC). Plot size was four rows by 40 ft long on 38 in. centers. Statistical design was a randomized complete block with four replications. Corn seed was treated with commercial rates of insecticide prior to planting. Counter was applied as a granular in furrow at a rate of 6 ounces per 1,000 row feet.

Five plants were randomly selected from row two of each plot to be caged with two adult sugarcane beetles (SCB) per cage (one male and one female). Selected plants were caged by inserting an 18–in. long by 3-in. diameter PVC pipe over each plant and tapping the pipe into place just below the soil line. One male and one female SCB were placed in each pipe. Plants were destructively sampled 5 days after infestation. Plants were examined for above-ground injury and then removed from the soil to ascertain a below-ground injury based on rating scales detailed in Table 1 . Rows two and three of each plot were harvested at harvest maturity (seed black layer). Injury-rating data and yield were analyzed with ANOVA and means were separated using Fisher’s Protected LSD ( P ≤ 0.05).

None of the insecticide treatments resulted in above-ground injury ratings that were significantly different from those observed for the untreated check ( Table 2 ). However, Poncho (0.5 and 1.25 mg ai/seed) and Poncho plus Counter resulted in significantly lower above-ground injury ratings compared with Cruiser (0.25 mg ai/seed). There were no statistical differences among treatments for below-ground injury ratings. There were no natural infestations of sugarcane beetles so yield is only representative of the impact of the insecticide treatments on other soil inhabiting pests that may have been present. There were no significant differences among treatments for yield.

Author notes