Tobacco Aphid Control on Flue-Cured Tobacco with Foliar Insecticides, 1995

Abstract

Abstract This experiment was conducted at the VPI & SU Southern Piedmont Agricultural Research and Extension Center, Blackstone, VA, to evaluate various foliar insecticides for TA control and to determine the resulting effects on the yield and price of flue-cured tobacco. Tobacco ‘K-326’ was transplanted into experimental plots on 16 May. Nine treatments and an untreated control were established in a RCB design with 4 replications. Plots, 4 X 40 ft (1 row X 24 plants), were separated by single untreated guard rows. Treatments were applied as foliar sprays with a CO2-pressurized backpack sprayer that delivered 28 gpa at 60 psi through 3, TX-12 nozzles/row on 3 Jul. Temperatures ranged from 85-88 °F during application. TA counts were made on the upper 4 leaves of 10 plants per plot before treatment and at 3, 7, 14 and 21 DAT. On 21 Aug, TA damage was rated on a scale of 0-10 where 0 = no injury and 10 = very severe injury as indicated by necrotic leaf tissue, honeydew, and sooty mold. Except for insect control, flue-cured tobacco production methods including transplanting, fertilization, topping, sucker control, and herbicide and fungicide applications followed recommendations by the Virginia Cooperative Extension Service. Dipel 4L was applied at 0.5 qt/acre to the entire test on 4 Aug for tobacco hornworm control. Tobacco was harvested as it ripened. It was cured, weighed, and graded by a USDA/AMS inspector, and yield and price were calculated. Price was based on 1995 market prices for the assigned grades. Data were analyzed by ANOVA and significantly different means were separated WD test (K-ratio = 100). TA count data were transformed to Logl0(X+l) before analysis. Actual means are presented in the table.