Effect of Insecticides on Pepper Insects, 2018 Open Access

To determine the effect of insecticides on pepper insect control, seedlings were transplanted in a sandy loam type soil on 10 May at the University of California Riverside’s Agricultural Operations field #10G. Experimental plots were 3 rows wide (5-ft centers) by 40 ft long and separated by a 3-ft buffer. The pepper transplants were drip-irrigated (water pH: 7.2–7.5). Treatments were replicated four times in an RCB block design. Application dates and a treatment list are shown in Table 1. All applications were made during working hours when wind conditions were mild. A tractor-mounted boom sprayer with 6 nozzles per row incorporated D-3 orifice disks, #25 cores, and 50 mesh screens. Operating pressure was 100 psi delivering 100 gpa. Rates are given in fl oz per acre unless otherwise specified. The Radiant and Sequoia, VST-006340 (16 fl oz) and Bioprotec, VST-006340 (32 fl oz) and Bioprotec, Venerate, and Asana XL were all sprayed the same days (14 and 28 Jun; 3, 12, 19, and 27 Jul). Treatments six and seven (IPM and Organic IPM) had specific rotations of products. The Intrepid and Sequoia (14 Jun and 12 Jul), Radiant (28 Jun and 19 Jul), and Vydate (3 and 27 Jul) were applied in rotation. The Pyganic (14 and 28 Jun; 19 Jul), Trilogy (28 Jun and 19 Jul), and Mycotrol and Entrust (3, 12, and 27 Jul) were applied as a rotation. The Organic IPM treatments did not use an adjuvant. The Radiant and Sequoia, IPM, and Asana XL treatments included Dyne-amic as an adjuvant at 0.25% vol/vol. The VST-006340 (16 fl oz) and Bioprotec, and VST-006340 (32 fl oz) and Bioprotec included Latron B-1956 as an adjuvant at 0.125% vol/vol. The Venerate treatment included Bond Max as an adjuvant at 18 fl oz. On 9 Aug, 50 mature-green to ripe fruit were harvested from the center row of each replicate (200 per treatment) and examined for internal damage by TFW, external damage BAW, hemipterous pests (lygus and SB), GPA, PP, and PW. Data were analyzed with ANOVA and Fisher’s-protected LSD test to detect differences among treatment means (P < 0.05 level, Fisher’s-protected LSD test).

Lepidopteran pressure was estimated to be low to moderate in the category of external damage by BAW, and there were no significant differences between the treatments for Lepidopterous insect damage. Internal damage by PW was not present this year. Field counts of PP had significant differences between treatments for number of adults in the Asana treatment. Damage to the calyx by TFW, BAW, and PW feeding showed no differences between treatments. No phytotoxicity was observed in any of the treatments.

This research was supported by industry gift(s) of pesticide and/or research funding and a grant from the California Pepper Commission.