The Use of Reflective Mulch Plus Insecticidal Control of Pepper Weevil on Jalapeño Pepper, 2015*

Pepper weevil is a devastating pest of pepper in Florida; fruit and flower buds are destroyed by adults feeding and ovipositing, and the larvae feed within the fruit. Insecticidal control is difficult because the immature stages are confined within the fruit. Many herbaceous insects are repelled by metalized UV reflective mulch although there is little or no information regarding effects on pepper weevil. For this trial, greenhouse-raised pepper seedlings were transplanted on 9 Sep at the Southwest Florida Research and Education Center in Immokalee FL. Beds were fumigated with Pic-Clor 60 EC (chloropicrin 56.7% + 1–3 dichloropropene 37.1%) at 300 lbs/ac on 18 Aug. Transplants were set 2 ft apart in two single row raised beds on 12 ft centers 420 ft in length, and covered with whiteface polyethylene film mulch. An RCB design was used with four replicates and seven treatments (Table 1). Two treatments including the use of metalized (aluminum coated) reflective polyethylene film mulch which was installed by hand over the white mulch in the designated areas. Each plot contained 10 plants with a 10 foot space left open between plots as a buffer. Granular 10-2-10 NPK fertilizer was mixed in the bed before planting at a rate of 125 lbs/N per acre, with the remaining requirements delivered as liquid 7-2-7 through drip irrigation over the growing season. Maintenance sprays included Kocide (1.5 lbs/acre) Manzate (1.5 lbs/acre) and Regalia (2 qts/acre) applied weekly as a tank mix to control foliar disease, in particular bacterial spot. Agri-mek SC (3.0 oz) was sprayed on 26 Oct and 2 Nov and Oberon (10.0 oz) on 9 and 25 Nov to control broad mites. Verimark was applied with a hand sprayer to deliver 3 ml of solution per plant directly to seedlings and soil media within 128 cell speedling tray. Soil drenches of Admire Pro were made 10 Sep by delivering a 90 ml suspension to the base of each plant using an EZ-Dose sprayer operating at 45 psi (Table 1). Verimark was chemigated 28 Sept and 12 Oct by sectioning off both drip tapes in each treated plot with a ball valve and pressurizing the tape using a 12 volt pump operating at 1 gpm to inject 0.5 gal of water, followed by 1 gal of suspension and finally a 2 gal of water (Table 1). 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 1). Sprays were applied at 60 GPA. Fallen fruit was held on the bed for counting by a strip of wood lathing secured to each edge with ground cloth staples. All fruit 2.0 inches or more in length was harvested and counted from all 10 plants per plot 2 Dec and 7 Jan. Visibly damaged fruit were culled and 15 fruit per plot per harvest date were cut open to inspect for internal damage by larval feeding. Marketable fruit was estimated by taking the total number of viable fruit (after culling visible damage) and multiplying by the ratio of good fruit/(good fruit + damaged fruit) for each plot.

Three treatments provided significantly more marketable fruit than the check at first harvest: (1) reflective mulch plus insecticides, (2) Verimark Tray Drench plus foliar insecticides and (3) Verimark drip treatment plus foliar insecticides, although not significantly different than the remaining three treatments (Table 2). On 7 Jan and over both harvests, all treatments except for the reflective mulch alone increased pepper yields, although there was no difference between mulch alone compared to Admire Pro with either of two spray regimens. No phytotoxicity was observed.

Author notes