Response of Selected Weed Species to Postemergence Imazethapyr and Bentazon

1995 ◽  
Vol 9 (2) ◽  
pp. 236-242 ◽  
Author(s):  
Troy A. Bauer ◽  
Karen A. Renner ◽  
Donald Penner

Imazethapyr and bentazon were applied with petroleum oil adjuvant in a factorial arrangement to weed species in greenhouse and field research to determine if postemergence weed control by imazethapyr was antagonized when bentazon was tank-mixed. Tank-mixing 840 g/ha of bentazon with 13 or 27 g/ha of imazethapyr increased redroot pigweed and eastern black nightshade dry weight as compared to Colby's expected values in the greenhouse. However, weed control was not reduced in field studies. Subsequent greenhouse studies indicated that soil interception and resulting root uptake of imazethapyr increased redroot pigweed control. Bentazon decreased foliar absorption of14C-imazethapyr by 15% and translocation of14C from the treated leaf by more than 50% compared tol4C-imazethapyr applied alone.

1998 ◽  
Vol 12 (2) ◽  
pp. 293-299 ◽  
Author(s):  
Kelly A. Nelson ◽  
Karen A. Renner

Field and greenhouse experiments were conducted to evaluate postemergence (POST) soybean injury and weed control with CGA-277476 and cloransulam-methyl alone and in tank mixtures. In the field, visible soybean injury was 12 to 14% from CGA-277476 and 9 to 13% from cloransulam-methyl 7 d after treatment. Tank mixtures of either herbicide with acifluorfen or acifluorfen plus thifensulfuron were more injurious than CGA-277476 or cloransulam-methyl applied alone. Both CGA-277476 and cloransulam-methyl reduced velvetleaf dry weight 82%, and cloransulam-methyl reduced common ragweed dry weight 92%. Neither herbicide adequately controlled common lambsquarters, redroot pigweed, nor eastern black nightshade. The addition of acifluorfen to the spray solution improved common ragweed, common lambsquarters, redroot pigweed, and eastern black nightshade control with CGA-277476 and improved common lambsquarters, redroot pigweed, and eastern black nightshade control with cloransulam-methyl. Tank mixing thifensulfuron with CGA-277476 or cloransulam-methyl increased common lambsquarters and redroot pigweed control. In the greenhouse, CGA-277476 at 20 g ai/ha reduced velvetleaf dry weight 98%, and 79 g/ha was required to reduce common ragweed dry weight 93%. Cloransulam-methyl at 4.4 g ai/ha reduced velvetleaf dry weight 98% and common ragweed dry weight 94% at 8.8 g/ha. Chlorimuron reduced yellow nutsedge dry weight more than CGA-277476 or cloransulam-methyl. Antagonism of POST graminicide activity by CGA-277476 was grass species and graminicide related. CGA-277476 reduced giant foxtail control by clethodim but not by quizalofop. Cloransulam-methyl tank mixed with clethodim or quizalofop controlled giant foxtail.


2007 ◽  
Vol 21 (1) ◽  
pp. 124-130 ◽  
Author(s):  
Adrienne M. Rich ◽  
Karen A. Renner

Reducing seeding rates in 19- or 76-cm row soybean below the optimum rate may reduce soybean competitiveness with weeds, and indirectly increase production costs to the grower. Field studies in 2001 and 2002 evaluated the effect of soybean seeding rate and row spacing on the emergence, growth, and competitiveness of eastern black nightshade (EBN) in soybean. EBN emergence ceased within 45 d after planting (DAP), and was similar across soybean seeding rates and row spacing. EBN control by glyphosate was not affected by soybean population or row spacing. Soybean planted in 19-cm rows was more competitive with EBN, regardless of seeding rate. Increasing the soybean seeding rate in 76-cm rows from 185,000 seeds/ha to 432,000 seeds/ha reduced EBN dry weight threefold at East Lansing and nearly twofold at Clarksville in 2002. There was no increase in EBN density or dry weight in 19-cm row soybean planted at 308,000 seeds/ha compared with 556,000 seeds/ha, whereas a seeding rate of 432,000 seeds/ha in 76-cm row soybean did not suppress EBN dry weight or increase soybean yield in the presence of EBN compared with a seeding rate of 308,000 seeds/ha.


Weed Science ◽  
1993 ◽  
Vol 41 (3) ◽  
pp. 347-352 ◽  
Author(s):  
Glenn R. Wehtje ◽  
John W. Wilcut ◽  
John A. Mcguire

Mixtures of chlorimuron and 2,4-DB were additive with respect to crop injury and were either additive or slightly antagonistic with respect to weed control in greenhouse experiments. Absorption and translocation of14C following application of14C-chlorimuron and14C-2,4-DB were not affected by the presence of the other unlabeled herbicide, except in Florida beggarweed and peanut where 2,4-DB affected distribution of14C-chlorimuron in the treated leaf. In field studies, maximum efficacy was obtained with mixtures of chlorimuron plus 2,4-DB applied 7 or 9 wk after planting. Florida beggarweed control was greatest with chlorimuron or chlorimuron mixtures while the addition of 2,4-DB to chlorimuron improved morningglory and sicklepod control. At 9 and 11 wk after planting, addition of 2,4-DB to chlorimuron controlled Florida beggarweed better than chlorimuron alone. Peanut yields were increased by the addition of 2,4-DB at later applications.


1987 ◽  
Vol 1 (2) ◽  
pp. 149-153 ◽  
Author(s):  
Michael R. Blumhorst ◽  
George Kapusta

In field studies, mefluidide {N-[2,4-dimethyl-5-[[(trifluoromethyl)sulfonyl] amino] phenyl] acetamide} was most effective as an enhancing agent for bentazon [3-(1-methylethyl)-(1H)-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide] and/or acifluorfen {5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid} when applied as a tank mixture compared to sequential applications. The influence of mefluidide rate on weed control was not consistent. Additives improved the control of several weed species evaluated, but mefluidide generally was only equal to petroleum oil concentrate (phytobland petroleum oil plus emulsifiers in an 83:17 ratio) as an enhancing agent for bentazon and/or acifluorfen.


Weed Science ◽  
1984 ◽  
Vol 32 (3) ◽  
pp. 336-342 ◽  
Author(s):  
Steven A. Fennimore ◽  
L. W. Mitich ◽  
Steven R. Radosevich

The interference between dry bean (Phaseolus vulgarisL. var. Red Kidney), black nightshade (Solanum nigrum♯3SOLNI), and barnyardgrass (Echinochloa crus-galli♯ ECHCR) was examined in replacement series experiments. A modified replacement series experiment also was performed to examine the effects of no interference, and intraspecific and interspecific interference on the height, leaf area, and dry weight of bean, black nightshade, and barnyardgrass. In both types of competition experiments, bean germinated earlier than either weed species and caused significant reductions in weed height, leaf area, and dry weight. The impact of bean upon itself was always greater than the effect of either weed species. In laboratory studies, barnyardgrass and black nightshade seeds were subjected to eight concentrations of trifluralin (α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine). Black nightshade was 100 times more tolerant to trifluralin than barnyardgrass. Field studies, conducted at several locations in the Central Valley of California in which trifluralin-treated plots were compared with nontreated plots, demonstrated that trifluralin favors trifluralin-tolerant weeds (black nightshade), but trifluralin-sensitive weeds (barnyardgrass) have not been eliminated despite 20 yr of trifluralin use.


Weed Science ◽  
1984 ◽  
Vol 32 (3) ◽  
pp. 327-335 ◽  
Author(s):  
Alex G. Ogg ◽  
Jean H. Dawson

Under irrigated field conditions at Prosser, WA, Russian thistle [Salsola kali(L.) var.tenuifoliaTausch. ♯3SASKR] began to emerge by mid-March each year and usually had completed its emergence by May 1. Common lambsquarters (Chenopodium albumL. ♯ CHEAL) was the next to appear, usually during the third or fourth week of March. Barnyardgrass [Echinochloa crus-galli(L.) Beauv. ♯ ECHCG], redroot pigweed (Amaranthus retroflexusL. ♯ AMARE), hairy nightshade (Solarium sarrachoidesSendt. ♯ SOLSA), black nightshade (5.nigrumL. ♯ SOLNI), eastern black nightshade (S. ptycanthumDun.), and cutleaf nightshade (S. triflorumNutt. ♯ SOLTR) generally began to emerge during the first 2 weeks of April and emergence generally peaked mid-April to mid-May. Russian thistle and cutleaf nightshade had the most restricted emergence patterns, whereas seedlings of common lambsquarters, redroot pigweed, hairy nightshade, and black nightshade emerged each month from April through September. Shallow tillage at monthly intervals increased the overall emergence of common lambsquarters, redroot pigweed, black nightshade, and eastern black nightshade; decreased the emergence of barnyardgrass; and had no effect on the emergence of Russian thistle, cutleaf nightshade, or hairy nightshade.


1994 ◽  
Vol 8 (4) ◽  
pp. 766-771 ◽  
Author(s):  
Aaron Hager ◽  
Karen Renner

Several herbicides control common ragweed postemergence in soybean. However, weed response may be altered if herbicides are tank-mixed and the choice of additive may also influence the degree of weed control. Imazethapyr and thifensulfuron could be tank-mixed with bentazon for broadleaf weed control and visual crop injury reduced compared to a bentazon plus acifluorfen tank-mix. Experiments determined common ragweed control with these herbicides and herbicide combinations when applied with various additives. In the greenhouse, bentazon at 560 g ai/ha reduced common ragweed dry weight 95 to 97%. Common ragweed control with imazethapyr at 35 g/ha increased by 13 and 7% when 28% urea ammonium nitrate was applied with nonionic surfactant or petroleum oil adjuvant, respectively. Tank-mixing imazethapyr with bentazon did not change dry weight of common ragweed compared with bentazon. Bentazon plus thifensulfuron plus nonionic surfactant required the addition of 28% urea ammonium nitrate to reduce dry weight of common ragweed comparable to that with bentazon. In field research, bentazon at 1120 g/ha reduced common ragweed dry weight 78 to 81%. Tank-mixing bentazon with thifensulfuron at 4.5 g/ha or imazethapyr at 71 or 35 g/ha reduced common ragweed dry weight at 14 d after treatment by 89 to 91%, thus enhancing control compared to each herbicide applied alone. Adding 28% urea ammonium nitrate to bentazon plus imazethapyr or bentazon plus thifensulfuron tank-mixes did not increase control compared to these treatments applied with either nonionic surfactant or petroleum oil adjuvant. By 28 d after treatment only imazethapyr at 35 or 71 g/ha plus 28% urea ammonium nitrate plus nonionic surfactant or petroleum oil adjuvant and bentazon plus imazethapyr tank-mixes provided 85% or more control of common ragweed in 1991, and only imazethapyr at 71 g/ha plus 28% urea ammonium nitrate plus petroleum oil adjuvant or imazethapyr at 71 g/ha plus bentazon provided greater than 78% common ragweed control in 1992. Soybean yield was not different from the handweeded control only where bentazon plus 71 g/ha of imazethapyr or acifluorfen at 560 g/ha was applied.


Weed Science ◽  
2003 ◽  
Vol 51 (6) ◽  
pp. 1016-1021 ◽  
Author(s):  
Robin R. Bellinder ◽  
Marija Arsenovic ◽  
Denis A. Shah ◽  
Bradley J. Rauch

The efficacies of bentazon and fomesafen in controlling annual weeds in dry and edible pod beans in New York State were investigated in greenhouse and field experiments. Dose responses to bentazon and fomesafen were studied for four weed species (ragweed, velvetleaf, eastern black nightshade, and hairy nightshade) under greenhouse conditions. Herbicides were applied at cotyledon to two-, two- to four-, and four- to six–true leaf stages, both with and without a crop oil concentrate (bentazon) or a nonionic surfactant (fomesafen). Field studies were conducted for 2 yr for all weed species except eastern black nightshade, for which no adequate field populations were found. Field studies confirmed greenhouse results, indicating that weed control could be improved by the use of an adjuvant, but there were exceptions. In general, adjuvant usage improved the efficacy of fomesafen more than it did with bentazon. The minimum rates of herbicide required for effective and consistent control was dependent on the particular combination of weed species, herbicide and its rate of application, growth stage at which the application was made, and adjuvant usage.


1997 ◽  
Vol 11 (1) ◽  
pp. 105-109
Author(s):  
Steven J. Langton ◽  
R. Gordon Harvey ◽  
John W. Albright

Field studies conducted in 1991 to 1993 evaluated the efficacy of clomazone applied at various timings for weed control in soybean. Clomazone applied 45, 30, 15, or 0 days prior to planting (DPP) provided season-long control of velvetleaf and giant foxtail. In 1991 and 1992 clomazone alone 30 and 45 DPP failed to control redroot pigweed. Clomazone alone 45 DPP failed to control common lambsquarters. In 1991 and 1992 clomazone at 0.84 kg/ha plus metribuzin applied 45 DPP failed to control redroot pigweed. The addition of metribuzin plus chlorimuron to the above clomazone treatments resolved these weed control deficiencies. Weed control in 1993 was nearly complete across all clomazone treatments. In 1993 clomazone treatments which included metribuzin or metribuzin plus chlorimuron applied PPI or PRE reduced yield. Herbicide injury is the likely cause of this reduction because most treatments in 1993 provided 99% control of all weed species.


1998 ◽  
Vol 12 (3) ◽  
pp. 458-462 ◽  
Author(s):  
John A. Ackley ◽  
Henry P. Wilson ◽  
Thomas E. Hines

In field studies, in 1993, 1994, and 1995, clomazone at 390 g ai/ha and rimsulfuron at 35 g ai/ha were evaluated preplant incorporated (PPI) and postemergence (POST), respectively, for weed control and crop response in transplanted ‘Keystone RG3’ bell pepper. Clomazone did not injure bell pepper. Common lambsquarters and jimsonweed control was 77 to 95% by clomazone treatments but was variable by rimsulfuron treatments at 41 to 93% common lambsquarters control and 42 to 68% jimsonweed control; common ragweed control by both herbicides was unacceptable. Injury by rimsulfuron to bell pepper in the field was 19 to 47% at 21 DAT. In the greenhouse, injury to Keystone RG3 and three additional bell pepper varieties, ‘Camelot,’ ‘Jupiter,’ and ‘Memphis’ was similar at 44 to 62% by rimsulfuron at 17 to 35 g/ha POST, and bell pepper had lower height and dry weight than untreated controls. In the greenhouse, jimsonweed control was below 49% and black nightshade control was below 23% by 17 to 35 g/ha rimsulfuron. In these studies, clomazone controlled common lambsquarters and jimsonweed without injury to bell pepper. The solanaceous weeds treated in this study were not well controlled by rimsulfuron, and bell pepper was not sufficiently tolerant to rimsulfuron to permit its use in this crop.


Sign in / Sign up

Export Citation Format

Share Document