Control of Tobacco Wikeworms with Winter and Spring Applications of Lorsban, 1992:

Abstract

Plots were established at the Border Belt Tobacco Research Station near Whiteville, NC, on 3 Mar. Plots were 22 plants long (ca 13.7 m) and 4 rows wide (1.2 m between rows) and were arranged according to a randomized complete-block design having 8 treatments and 4 blocks. The predominant soil type was Goldsboro fine sandy loam (pH 6.5). Winter treatments were made on 3 Mar and spring treatments were made on 23 Apr. Sprays were applied using a CO2-powered sprayer fitted with 5, 8004 Spraying Systems flat-fan nozzles (20 inches apart) on a 80 inch boom at 30 psi and a delivery rate of 25 gal/acre. All treatments were incorporated via ridging immediately after application. Tobacco was transplanted on 24 Apr. Soil moisture was excellent at the time of transplanting. Twenty-six days after transplanting, 10 consecutive plants from row 2 in each plot were gently pulled from the soil. The roots and underground portions of the stems were visually examined and rated for wireworm damage as follows: 0 = no damage; 1 = feeding scars on root surface; 2 = feeding reaching pith with tunneling < 1 cm; 3 = pit tunneling from 1-5 cm; 4 = pith tunneling > 5 cm; and 5 = dead plant. Using this data, the avg wireworm rating and the proportion of wireworm damaged plants was calculated. Data were subjected to ANOVA and WD, K = 100. Proportion of plants infested was transformed to arcsine √ proportion before ANOVA.