Control of Beet Armyworm and Southern Armyworm with Biological Insecticides on Bell Pepperfall 1993

Abstract

Abstract Seedlings of “Jupiter” bell peppers were transplanted on 1 Oct, 12 inches apart in single rows on raised beds covered with whitefaced polyethylene mulch and sub-surface irrigated. Beds had been prepared by fumigation with chloropicrin methyl bromide 33/67% 220 lbs/acre and fertilized with a bottom mix of 800 lbs/acre of 5-16-8 and a top mix of 1000 lbs/acre of 19-0-30. The plants were sprayed weekly with a fungicide mix of 3.0 lbs Kocide DF and 1.0 lb/acre Maneb 80 W/acre. Four 240-foot rows on 12 foot centers were used, each divided into 7 plots 33 feet long with 18 inches between plots. Six treatments and an unsprayed check were randomly assigned to each row giving 4 replications. Treatments were applied weekly starting 22 Oct following verification of pest infestation. An adjuvant, ASPA 80®, was added to each spray tank at the rate of 3 oz/100 gallon of mix. Applications were made using a 12 tank sprayer mounted on a small trailer and drawn by a 4-wheel drive Suzuki ATV equipped with a diaphragm pump operating at 80 lb/in2 powered by a gasoline engine. Spray was delivered through a single row boom utilizing 3 drops, two on the side carrying 1 or 2 Albuz ATR® “red” ceramic tipped nozzles each depending on plant size and one in the middle carrying a single nozzle for a maximum delivery rate of 35 gpa. Weekly sampling began 21 Oct (pre-treatment) and was initiated from a random start 3-5 plants from the end and continued with every other plant until 8 were sampled. Number and size of the larvae were noted and percent leaf damage to 3 leaf-size categories was estimated. Plants for harvest were selected as above and fruit of marketable size and age was harvested on 16 Dec and again on 23 Dec from the same plants. Number and weight in pounds of marketable peppers were recorded for each plot. Number and weights of culls were recorded in two separate categories: insect damaged and not insect damaged. A small number of culls from pepper weevil damage, noted during the 23 Dec harvest, was included in the general insect-damage category. Data on total numbers of beet armyworm, southern armyworm and leaf damage were subjected to an analysis of variance followed by Duncan’s multiple range test in the event of a significant F value.