Absorption, translocation, and metabolism of primisulfuron and nicosulfuron in broadleaf signalgrass (Brachiaria platyphylla) and corn

Abstract

Broadleaf signalgrass is sensitive to nicosulfuron and resistant to primisulfuron, but corn is resistant to both. Research was conducted to determine the effect of varying light level and air temperature on absorption, translocation, and metabolism of nicosulfuron and primisulfuron in broadleaf signalgrass and corn. Corn absorbed between 60 and 85% of the applied nicosulfuron and primisulfuron within 72 h after treatment (HAT), depending on environmental treatment. Absorption, translocation, and metabolism all tended to be more rapid at higher temperature and light intensity. Nicosulfuron and primisulfuron translocation out of the treated leaf was < 4.5% of herbicide absorbed through 72 HAT. Corn rapidly metabolized both herbicides in both environments. However, primisulfuron was metabolized more rapidly (high = 99%, low = 92%) than nicosulfuron (high = 95%, low = 78%). Broadleaf signalgrass absorbed 20% more nicosulfuron than primisulfuron through 72 HAT. Nicosulfuron translocation out of the treated leaf in broadleaf signalgrass was ≤ 15% absorbed through 72 HAT, while primisulfuron translocation was ≤ 4% during the same time period. Primisulfuron metabolism was more rapid than nicosulfuron in broadleaf signalgrass. During the first 4 HAT, broadleaf signalgrass metabolized > 20 times more primisulfuron than nicosulfuron. By 72 HAT, broadleaf signalgrass under conditions of high light and temperature had metabolized nearly 90% of the primisulfuron absorbed but ≤ 7% of the nicosulfuron absorbed was metabolized during the same time. These results suggest that differential activity of nicosulfuron and primisulfuron on broadleaf signalgrass may be based on differential rates of metabolism to nonphytotoxic compounds; uptake and translocation differences agree with the differential broadleaf signalgrass activity. Additionally, environment has the potential to affect rates of sulfonylurea absorption, translocation, and metabolism.

Response of Arabidopsis thaliana to 22 ALS inhibitors: baseline toxicity and cross‐resistance of csr1‐1 and csr1‐2 resistant mutants

“…Although absorption and translocation of ALS‐inhibiting herbicides are said to differ among species (Ackley et al. , 1999; Gallaher et al. , 1999), this absence of conserved ranking between species could be explained in part by the varying abilities of species to conduct detoxification.…”

Response of Sensitive Corn Hybrids to the Association of Nicosulfuron and Timing of Nitrogen Application

“…In situation of increasing the percentage, niculfuron couldn't be metabolized, bulliform and fundamental cells growth would be suppressed (Môro and Damião Filho,1999). Most nicosulfuron translocation within plants is to apical meristems (Gallaher et al, 1970).…”

“…Among herbicides for corn crops, nicosulfuron is a POST herbicide that controls weeds by inhibiting ALS enzyme (Acetolactate Synthase), which is responsible for synthesizing branched-chain amino acids (Gallaher et al, 1970;Stankiewicz-Kosyl et al, 2017). Many farmers in Midwestern Brazil do not use nicosulfuron because corn is sensitive to it.…”

Influence of selected soil-climatic parameters and application method of tribenuron methyl on biomass productivity and amino acids content in weeds

“…Several scientific papers report that the effects of herbicides are strongly affected by environmental conditions (Gallaher et al 1999, Coetzer et al 2001, Hatterman-Valenti et al 2006. Under adverse soil-weather conditions, such as low * Means within weed species followed by the same letter are not significantly different at p = 0.05. temperature, relative humidity and soil moisture, herbicide activity may be reduced considerably giving lower efficacy than expected, while under optimal circumstances i.e.…”