Mustard tolerance to clopyralid applied alone or with ethametsulfuron

1994 ◽  
Vol 74 (3) ◽  
pp. 635-641
Author(s):  
H. A. Loeppky ◽  
R. E. Blackshaw

Mustard is a drought-tolerant crop well adapted to the Brown and Dark Brown soils of the Prairies; however, lack of broad-leaved weed control limits production. Two field studies were conducted at Indian Head, Saskatchewan and Lethbridge, Alberta to determine the response of brown and oriental mustard (Brassica juncea (L.) Coss), and yellow mustard (B. hirta Moench) to clopyralid. Clopyralid was applied at 0.10, 0.15, 0.20, 0.30, 0.60 kg a.i. ha−1 at the 4- or 10-leaf stage in one experiment. The other was a factorial experiment of clopyralid at 0.10, 0.20, and 0.30 kg a.i. ha−1 with ethametsulfuron at 0.01, 0.02, and 0.03 kg a.i. ha−1. Clopyralid applied at 0.15 kg a.i. ha−1, the lowest rate at which it is registered for weed control in canola, resulted in brown mustard yield reductions of 21%, oriental mustard yield reductions of 23% and yellow mustard yield reductions of 9% over 5 site years. This rate of clopyralid applied with ethametsulfuron reduced brown, oriental and yellow mustard yield by 30, 33 and 8%, respectively. Oil content was also reduced by clopyralid. Clopyralid cannot be used for weed control in mustards. Key words: Crop tolerance, growth stage, clopyralid, ethametsulfuron, seed yield, oil content

1990 ◽  
Vol 70 (1) ◽  
pp. 237-245 ◽  
Author(s):  
R. E. BLACKSHAW ◽  
H.-H. MUENDEL ◽  
D. A. DERKSEN

Field studies were conducted in 1986, 1987 and 1988 at Lethbridge, Alberta and in 1987 and 1988 at Indian Head, Saskatchewan to determine herbicides suitable for selective control of weeds in safflower (Carthamus tinctorius L.). Safflower exhibited acceptable tolerance to trifluralin, ethalfluralin, sethoxydim, fluazifop-p-butyl, clethodim, diclofop methyl, difenzoquat, imazamethabenz, chlorsulfuron, thiameturon, metsulfuron and DPX-A7881 over all years and locations. These herbicides offer the grower the option of preplant incorporated or postemergent herbicide application or a combination of the two. A mixture of thiameturon plus DPX-L5300 caused severe injury to safflower, reducing yield, oil content, and seed weight. Desmedipham, phenmedipham, and mixtures of these herbicides injured safflower at Lethbridge but not at Indian Head. Weeds reduced safflower yield by 39–73% over the 3 yr of the study. Control of weeds in safflower is essential to obtain optimum yields.Key words: Crop tolerance, seed yield, oil content, seed weight, weed competition


Weed Science ◽  
1994 ◽  
Vol 42 (4) ◽  
pp. 601-607 ◽  
Author(s):  
John W. Wilcut ◽  
John S. Richburg ◽  
E. Ford Eastin ◽  
Gerald R. Wiley ◽  
F. Robert Walls ◽  
...  

Field studies conducted at six locations in Georgia and one location in Virginia evaluated imazethapyr and imazethapyr mixtures for weed control, crop tolerance, and peanut yield. Imazethapyr applied early postemergence controlled bristly starbur, coffee senna, common cocklebur,Ipomoeaspecies, jimsonweed, prickly sida, and smallflower morningglory at least 91% and controlled yellow and purple nutsedge 88 and 98%, respectively. Paraquat plus bentazon applied early postemergence did not control the aforementioned weeds as well as imazethapyr or imazethapyr mixtures. Paraquat applied with imazethapyr reduced bristly starbur control 15% compared to imazethapyr alone but did not influence control of the other species. Imazethapyr control of bristly starbur was not improved by the addition of bentazon. Sicklepod control was less than 24% with imazethapyr and was at least 58% with imazethapyr plus paraquat Imazethapyr plus paraquat controlled sicklepod better than paraquat plus bentazon at three of the four locations evaluated. Imazethapyr did not control Florida beggarweed, while imazethapyr plus paraquat controlled at least 53%. Peanut injury was minimal 30 d after application for all treatments.


2017 ◽  
Vol 15 (1) ◽  
pp. e1001
Author(s):  
Rubia Rasool ◽  
Makhan S. Bhullar ◽  
Gurjeet S. Gill

Phalaris minor Retz. has evolved multiple herbicide resistance in wheat growing areas in northwestern India. An understanding of the effect of growth stage on herbicide tolerance of wheat and control of P. minor will help in selecting the most appropriate herbicide for different situations. The weed control and crop safety of four commonly used wheat herbicides (sulfosulfuron, pinoxaden, fenoxaprop plus metribuzin and mesosulfuron plus iodosulfuron), each applied at four different wheat growth stages was investigated in field studies for two years. P. minor plants were at 1, 2-3, 3-4 and 7-8 leaf stages when the herbicides were applied at Zadok 12-Z12, Z13, Z21 and Z23 stages of wheat, respectively. Sulfosulfuron application at Z12 and Z13 wheat stages (before first irrigation), provided >80% control of P. minor and produced wheat grain yield (4.5-4.7 t/ha) similar to the weed-free check (4.9 t/ha) in both years. Pinoxaden, fenoxaprop plus metribuzin and mesosulfuron plus iodosulfuron application at Z12 and Z13 wheat stages recorded significantly lower wheat grain yield (3.62-3.95 t/ha) due to poor weed control, crop toxicity or both. All the four herbicides were equally effective on P. minor when applied at Z21 wheat stage. At Z23 wheat stage, pinoxaden gave >90% control of P. minor and the highest wheat grain yield (4.82 t/ha). The results are expected to allow changes in the current recommendation of the timing of post-emergence herbicides for the management of P. minor in wheat.


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.


Weed Science ◽  
2003 ◽  
Vol 51 (6) ◽  
pp. 1002-1009 ◽  
Author(s):  
Dunk Porterfield ◽  
John W. Wilcut ◽  
Jerry W. Wells ◽  
Scott B. Clewis

Field studies conducted at three locations in North Carolina in 1998 and 1999 evaluated crop tolerance, weed control, and yield with CGA-362622 alone and in combination with various weed management systems in transgenic and nontransgenic cotton systems. The herbicide systems used bromoxynil, CGA-362622, glyphosate, and pyrithiobac applied alone early postemergence (EPOST) or mixtures of CGA-362622 plus bromoxynil, glyphosate, or pyrithiobac applied EPOST. Trifluralin preplant incorporated followed by (fb) fluometuron preemergence (PRE) alone or fb a late POST–directed (LAYBY) treatment of prometryn plus MSMA controlled all the weed species present less than 90%. Herbicide systems that included soil-applied and LAYBY herbicides plus glyphosate EPOST or mixtures of CGA-362622 EPOST plus bromoxynil, glyphosate, or pyrithiobac controlled broadleaf signalgrass, entireleaf morningglory, large crabgrass, Palmer amaranth, prickly sida, sicklepod, and smooth pigweed at least 90%. Only cotton treated with these herbicide systems yielded equivalent to the weed-free check for each cultivar. Bromoxynil systems did not control Palmer amaranth and sicklepod, pyrithiobac systems did not control sicklepod, and CGA-362622 systems did not control prickly sida.


1975 ◽  
Vol 85 (3) ◽  
pp. 533-539 ◽  
Author(s):  
A. Penny ◽  
J. F. Jenkyn

SUMMARYExperiments with winter wheat in 1972 and 1973 tested all combinations of ‘Nitro-Chalk’ ν. liquid N-fertilizer, 56 ν. 112 kg N/ha, 0 ν 5·6 1/ha of herbicide (2·8 kg acid equivalent/ha) and 0 ν 0·7 1/ha of mildew fungicide, all applied at growth stage 4–5 of the Feekes scale. The liquid fertilizer (26 % N) was a solution of ammonium nitrate and urea, the herbicide was a mixture of dichlorprop and MCPA and the mildew fungicide contained 75 % (w/v) of the active ingredient tridemorph.The herbicide and mildew fungicide were sprayed either alone or together and neither scorched the wheat leaves. Liquid N-fertilizer by itself slightly scorched the wheat leaves and scorch was increased by adding herbicide to it, but more by adding the fungicide and most by adding both; it was then severe, especially with 112 kg N/ha.Weed control after adding herbicide to the liquid fertilizer was at least as good as from herbicide sprayed alone.In July, foliar diseases were much more severe with 112 than with 56 kg N/ha, but effects of the other treatments, including fungicide, on foliar diseases, were then very small.With 56 kg N/ha, yields were slightly larger with ‘Nitro-Chalk’ alone than with the liquid N-fertilizer alone, but with 112 kg N/ha they were slightly larger with the liquid fertilizer; adding herbicide to the liquid fertilizer did not change these results. With either amount of N, adding mildew fungicide to the liquid fertilizer made it less good than ‘Nitro-Chalk’, presumably because of the damage from leaf scorch; adding both herbicide and fungicide to the liquid fertilizer increased the damage.


2009 ◽  
Vol 45 (4) ◽  
pp. 499-508 ◽  
Author(s):  
HEDI MIGHRI ◽  
AHMED AKROUT ◽  
JOSEPH CASANOVA ◽  
FELIX TOMI ◽  
MOHAMED NEFFATI

SUMMARYArtemisia herba-alba Asso has been successfully cultivated in the Tunisian arid zone. However, information regarding the effects of the harvest frequency on its biomass and essential oil yields is very limited. In this study, the effects of three different frequencies of harvesting the upper half of the A. herba-alba plant tuft were compared. The harvest treatments were: harvesting the same individual plants at the flowering stage annually; harvesting the same individual plants at the full vegetative growth stage annually and harvesting the same individual plants every six months. Statistical analyses indicated that all properties studied were affected by the harvest frequency. Essential oil yield, depended both on the dry biomass and its essential oil content, and was significantly higher from plants harvested annually at the flowering stage than the other two treatments. The composition of the β- and α-thujone-rich oils did not vary throughout the experimental period.


1992 ◽  
Vol 72 (1) ◽  
pp. 203-207 ◽  
Author(s):  
R. E. Blackshaw ◽  
D. A. Derksen

Greenhouse and field studies were conducted to determine the tolerance of cultivated mustards, Brassica juncea and B. hirta to the herbicide DPX-A7881 [methyl 2-(4-ethoxy-6-menthylamino-1,3,5-triazin-2-yl) (amino) (carbonyl) (amino) (sulfonyl) benzoate]applied at various rates and stages of growth. Cultivated mustards are tolerant to DPX-A7881 at rates required to control wild mustard (Sinapis arvensis L.) thus fallowing the previously impossible selective control of this weed in cultivated mustards.Key words: Crop tolerance, growth stage, seed yield, DPX-A7881, Ethametsulfuron


1990 ◽  
Vol 4 (1) ◽  
pp. 92-96 ◽  
Author(s):  
Joseph P. Reed ◽  
Franklin R. Hall ◽  
Donald L. Reichard

Field studies with flatfan, twinjet, flood and rotary atomizers were conducted in 1987 and 1988. The results indicated that tridiphane at 0.6 kg ai/ha plus atrazine at 1.7 kg ai/ha with 2.0 L/ha of soybean oil adjuvant was more effective in controlling giant foxtail and common lambsquarters when applied by the flatfan, twinjet, and rotary atomizers. Image analysis indicated that weed control by a postemergence herbicide was generally enhanced by better application coverage. Droplet size measurement by phase droplet particle/droplet analyzer demonstrated that the rotary atomizer produced a narrower range of droplet diameters between the Dv.1and Dv.9volumes than any of the other atomizers.


2018 ◽  
Vol 36 (0) ◽  
Author(s):  
L.H.S. ZOBIOLE ◽  
F.H. KRENCHINSKI ◽  
G. MORATELLI ◽  
N.V. COSTA

ABSTRACT: The effectiveness of a new product has a great importance to weed control, especially those that are difficult to control or resistant to, such as the sumatran fleabane (Conyza sumatrensis). The objective of this research was to evaluate the control of C. sumatrensis at different growth stages, using halauxifen-methyl in combination with other herbicides. The experimental design used was a randomized blocks in a 3x10 factorial scheme, with four replications. The plants of C. sumatrensis were evaluated at different growth: stage 1: plants with 8 leaves; Stage 2: plants with 19 leaves and stage 3: plants with 45 leaves fully expanded. The herbicides used were the association of glyphosate with the herbicides 2,4-D at 806, 943 and 1,209 g a.e. ha-1, halauxifen-methyl + diclosulam at 5.06 g a.e. ha-1 + 25.52 g a.i. ha-1 and 6.32 g a.e. ha-1 + 31.87 g a.i. ha-1, halauxifen-methyl + 2,4-D at 5.00 + 783 g a.e. ha-1 and 6,0 + 940 g a.e. ha-1 and halauxifen-methyl at 5.0 and 6.0 g a.e. ha-1 and untreated, totaling 10 treatments. The herbicides demonstrated satisfactory control of the plants in Stage 1 at 50 DAA, with the exception of the glyphosate + 2,4-D treatment at the lowest rate. However for Stages 2 and 3 the halauxifen-methyl + diclosulam in both rates, provided superior controls in relation to the other treatments. The control of sumatran fleabane was facilitated when their management occurs in the early stages of development, however independent of the development stage, the best controls obtained were with the treatment containing glyphosate + halauxifen-methyl + diclosulam at 1,440 g a.e. ha-1 + 6.32 g a.e. ha-1 + 31.87 g a.i. ha-1. Thus, combinations of herbicides containing halauxifen-methyl are another option to control C. sumatrensis in agricultural systems.


Sign in / Sign up

Export Citation Format

Share Document