Insecticidal Control of Pepper Weevil on Jalapeno Pepper, 2013 *

Pepper weevil is the key pest of pepper in the southeastern United States, destroying flower buds and fruit through adult feeding, oviposition, and larval feeding within the fruit. Insecticidal control is problematic because all immature stages plus the teneral adult are confined within the fruit. For this trial located at the Florida Research and Education Center in Immokalee, FL, three single-row raised beds were prepared on 12-ft centers 420 ft in length. Granular 10-2-10 NPK fertilizer was incorporated before planting at a rate of 100 lbs/N per acre, beds were fumigated with 100 lb/acre 50:50 methyl bromide + chloropicrin, two drip tapes with 8-in emitter spacing were laid down, and beds were covered with whiteface polyethylene film mulch. Greenhouse-raised pepper seedlings were transplanted 24 inches apart. An RCB design was used with four replicates and nine treatments ( Table 1 ). Each plot contained 10 plants with a 15-ft space left open between plots as a buffer. The remaining requirements were delivered as liquid 7-2-7 through drip irrigation over the growing season. Maintenance sprays included Kocide (1.5 lbs/acre) and Manzate (1.5 lbs/acre) applied weekly as a tank mix to control foliar disease, in particular bacterial spot.

Foliar applications were made with a high-clearance sprayer operating at 180 psi at 2.3 mph, with spray delivered through two vertical booms equipped with yellow Albuz® ATR 80 hollow cone nozzles ( Table 2 ). All sprays were applied at 60 gpa. Fallen fruit was held on the bed for counting using a strip of wood lathing secured to each edge with ground cloth staples. All fruit 2.0 inches or more in length were harvested, and all fallen fruit were collected and counted from all plants on 25 Nov and 10 Dec, and from six plants per plot on 20 Dec, 17 Jan, and 7 Feb. Visibly damaged fruit were culled, and all apparently undamaged fruit up to 15 harvested from each plot were cut longitudinally and inspected for pepper weevil larvae or pupae and feeding damage. The number of weevil-damaged fruit was estimated by adding the number with visible damage to the product of the proportion of damaged fruit in the cut subsample multiplied by the total number of fruit without visible damage. Data were subjected to ANOVA and means separated using LSD ( P  = 0.05).

Weevil pressure was light and confined to one portion of the field at the start of the trial and did not increase or spread through plots until January 2014. No significant differences were observed on 25 Nov and 10, 20 Dec harvests. On 17 Jan, only plants treated with Vydate/Actara, Vydate/Torac, and 16.4 oz rate of ISK 3106 produced significantly higher yield than the untreated control, whereas on 7 Feb, the 11 oz rate of ISK3106 was added to the list. On that date, marketable yield response to the 8 qt rate of MBI206 bm1 EP1 was not significantly different from either rate of the ISK3106 or the untreated check. No phytotoxicity was observed.

Author notes