Tolerance of Maryland-Type Tobacco (Nicotiana tabacum) to Sulfentrazone¹

Abstract

Field experiments were conducted from 2000 to 2002 at the Southern Maryland Research and Education Facility located in Upper Marlboro, MD to evaluate PPI and preemergence/prior-to-transplanting (PRE-T) applications of sulfentrazone in combination with clomazone or pendimethalin on crop injury and yield of Maryland-type tobacco. Pendimethalin was also evaluated alone. The highest levels of tobacco injury in 2000 occurred 3 wk after treatment (WAT) with PPI applications of sulfentrazone plus pendimethalin at 0.35 + 0.84 and 0.42 + 0.84 kg ai/ha, averaging 37 and 28%, respectively. In 2001, PPI applications of sulfentrazone plus clomazone at 0.42 + 0.84 kg/ha or sulfentrazone plus pendimethalin at 0.42 + 0.84 kg/ha caused 18 and 12% injury, respectively, 3 WAT. Injury in 2002 with all treatments averaged 7% or less 3 WAT. Greater rainfall through 3 WAT occurred in 2000 than in 2001 or 2002, likely contributing to the higher injury in 2000. Tobacco yields were generally similar among herbicide treatments in 2000 and 2001, and tobacco yields for all herbicide treatments were similar in 2002. The quality index was similar in 2000 and 2001, and varied slightly in 2002 among all herbicide treatments. Although a lower price was calculated for the nontreated controls, price did not vary among most herbicide treatments each year. This research shows that injury to Maryland-type tobacco can occur with sulfentrazone in combination with clomazone or pendimethalin, particularly when incorporated, and when high rainfall occurs soon after transplanting. However, injury is transient and generally has no negative influence on tobacco yield, quality, or price.

Sulfentrazone Adsorption and Mobility in Surface Soil of The Southern United States

“…Sulfentrazone is a phenyl triazolinone herbicide that inhibits protoporphyrinogen oxidase in the chlorophyll biosynthetic pathway (Vencill 2002); it has potential for use in several crops in the United States. Tobacco (Nicotiana tabacum L.) production has the highest use rate of sulfentrazone from a market-share perspective (Ritter et al 2005). Sulfentrazone is the foundational herbicide for weed control in tobacco, providing control of many grass and broadleaf weeds.…”

Dark Tobacco (Nicotiana tabacum) Tolerance to Trifloxysulfuron and Halosulfuron

“…Herbicides registered for use in dark tobacco include sulfentrazone, clomazone, pendimethalin, napropamide, and sethoxydim. Sulfentrazone controls or suppresses several annual broadleaf weeds, nutsedges, and grasses (Anonymous 2006d;Fisher et al 2004;Ritter et al 2005). However, it does not control common ragweed (Ambrosia artemisiifolia L.) and giant ragweed (Ambrosia trifida L.), which are presently two of the most common and troublesome weeds in dark tobacco (Bailey 2004).…”