Absorption, Translocation, and Toxicity of Foliar-Applied Imazaquin in Yellow and Purple Nutsedge (Cyperus esculentusandC. rotundus)

Abstract

Imazaquin {2-[4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-3-quinolinecarboxylic acid} absorption, translocation, and toxicity were investigated in yellow nutsedge (Cyperus esculentusL. # CYPES) and purple nutsedge (C. rotundusL. # CYPRO) after foliar treatment. Imazaquin rates from 0.125 to 0.375 kg ai/ha were sprayed on nutsedge plants at the four-leaf stage. Compared to untreated plants, these rates reduced the main shoot growth of yellow nutsedge by 70 to 86% and that of purple nutsedge by 80 to 92% at 28 days after application (DAA). However, the regrowth as measured by tiller production was significantly greater at 0.125 and 0.188 kg/ha rates than at higher rates. The plants treated with 0.313 and 0.375 rates had no rhizomes or tubers at the 28 DAA sampling. In yellow nutsedge, absorption of14C-imazaquin increased from 36% at 1 DAA to 57% at 8 DAA. of the total absorbed14C, 12% translocated from the treated area by 8 DAA. Roots and rhizomes accumulated equal amounts of radioactivity. In purple nutsedge, the absorption of imazaquin increased from 17% at 1 DAA to 53% at 8 DAA. Translocation of absorbed14C in purple nutsedge at 8 DAA was 21%. Rhizomes accumulated significantly greater amounts of14C than the roots.

Glyphosate Injury, Rainfastness, Absorption, and Translocation in Purple Nutsedge (Cyperus rotundus)

“…Norflurazon {4-chloro-5-(methylamino )-2-[3-(trifluoromethyl)phenyl]-3(2H)-pyridazinone} and pyrithiobac { 2-c h 10 ro-6-[( 4, 6-d i me thoxy -2 -py ri midinyl)thio]benzoic acid) in cotton (Gossypium hirsutum L.) and chlorimuron {ethyI2- [[[[4-chloro-6-methoxy-2pyrimidinyl)amino ]carbonyl]amino ]sulfonyl]benzoate }, imazaquin (2-[4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imadozol-2-yl]-3-quinolinecarboxylic acid}, imazamox (2-[ 4,5-dihydro-4-methyl-4-( I-methylethyl)-5-oxo-1H-imidazol-2-yl]-5-(methoxymethyl)-3pyridinecarboxylic acid}, and sulfentrazone {N-[2,4-dichloro-5-[4-( difluoromethy 1 )-4,5-dihydro-3-methy 1-5oxo-1H-l,2,4-triazol-l-yl]phenyl]methanesulfonamide} in soybean [Glycine max (L.) Merr.] provide various levels of purple nutsedge control (Anonymous 1998;Jordan 1996;Nandihalli and Bendixen 1988;Reddy and Bendixen 1988;Wilcut 1998;WSSA 1994WSSA , 1998.…”

Effect of MON 12037 on the Growth and Tuber Viability of Purple Nutsedge (Cyperus rotundus)

“…In greenhouse studies using purple nutsedge grown in pots, significant reductions in shoot and root tuber growth and in shoot regrowth were obtained with foliar applications of rmazaquin { (t)-2-14,5-dihydro-4-methyl-4 -(1methy lethyl ) -5o x o -L H -rmrdazol-Z -yl I -3qui no linecarboxylic acid) (Derr and Wilcut 1993;Nandihalli and Bendixen 1988a), imazethapyr { (I)-2-14,5-dihydro-4 -methyl-4 -( 1methy I ethy I ) -5o x o -I Htmrdazol-2 -yll -5ethyl-3-pyridinecarbolilic acid) (Richburg et al 1993), AC 263,222 { ( t )-2-14,5 -dihydro -4-methyl-4-( 1methy lethy 1 ) -5o x o -I H -rmrdazol-Z -yI)-5me thy I -3p yri dinecarboxylic acid) (Richburg et al 1994), MON 12037 (Vencill et al 1995), and soil applications of chlorimuron (Reddy and Bendixen 1989). These results demonstrate that when applied to young, actively growing plants, excellent control was achieved and regrowth was prevented.…”

“…In greenhouse studies using purple nutsedge grown in pots, significant reductions in shoot and root tuber growth and in shoot regrowth were obtained with foliar applications of imazaquin {( ± )-2-[ 4,5-dihydro-4-methyl-4-( I-methylethyl)-5-oxo-lH-imidazol-2-yl]-3-quinolinecarboxylic acid) (Derr and Wilcut 1993;Nandihalli and Bendixen 1988a), imazethapyr (±)-2-[4,5-dihydro-4-methyl-4-( I-methylethyl)-5-oxo-1H-imidazol-2-yl]-5ethyl-3-pyridinecarbolilic acid) (Richburg et a1. 1993), AC 263,222 {(±)-2-[4,5-dihydro-4-methyl-4-(1-methy lethy 1)-5-oxo-l H -imidazol-2-y 1] -5-methy 1-3-pyridinecarboxylic acid} (Richburg et a1.…”

Yellow Nutsedge Control in Landscape Plants

“…Fomesafen, chlorimuron, and imazaquin are new herbicides in the diphenyl ether, sul-fonylurea, and imidazolinone herbicide families, respectively. Although they are only registered for use in agronomic crops, they reportedly control yellow nutsedge (Nandihalli and Bendixen, 1988;Reddy and Bendixen, 1988;G. R. W., unpublished data).…”

“…These results support those presented in Table 1, in which 100% control of yellow nutsedge was obtained from PPI and PRE applications of imazaquin and chlorimuron. Nandihalli and Bendixen (1988) reported that soil applications of imazaquin above the tubers (mimicking PPI and PRE applications) inhibited regrowth more than placement below the tuber.…”