Efficacy and selectivity of post-emergent application of flumioxazin and oxyfluorfen in sunflower

Four efficacy and selectivity small plot field trials were carried out in four sunflower hybrids at two localities in Middle Bohemia during 2008 and 2009 with herbicides containing the active ingredients flumioxazin and fluorochloridone. For Chenopodium album, an efficacy of 97% was found after pre-emergent application of fluorochloridone + acetochlor; the efficacy of oxyfluorfen was 88–95%; the efficacy of flumioxazin was below 50% at both tested application rates (30 and 60 g/ha) and application timings (2 sunflower leaves and 4 to 6 sunflower leaves); efficacy of flumioxazin increased to 67% and 69%, when surfactants were added (isodecyl alcohol ethoxylate and heptamethyltrisiloxan). Full control of Amaranthus retroflexus was found after all pre-emergent and early post-emergent herbicide treatments; efficacy of late post-emergent herbicide treatments was below 93%. Full control of Mercurialis annua was found only after application of oxyfluorfen. Thlaspi arvense was fully controlled by fluorochloridone + acetochlor (pre-emergent) and oxyfluorfen (in both application terms). Selectivity of the four tested sunflower hybrids to fluorochloridone + acetochlor, bifenox and flumioxazin was acceptable (phytotoxicity 6 to 27%). Higher phytotoxicity (23–45%) was recorded when surfactants were added to flumioxazin. The highest phytotoxicity (68–81%) was recorded after the application of oxyfluorfen.  

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Seedling establishment early on an abandoned field

Plant Protection Science ◽

10.17221/8375-pps ◽

2001 ◽

Vol 37 (No. 3) ◽

pp. 121-127

Author(s):

J. Štolcová

Keyword(s):

Species Diversity ◽

Species Composition ◽

Seedling Establishment ◽

Dominant Species ◽

Chenopodium Album ◽

Amaranthus Retroflexus ◽

Abandoned Field ◽

Thlaspi Arvense ◽

Weed Infestation ◽

Small Plot

The effect of sporadic cultivation on seedling establishment on a field abandoned for 1–4 years was investigated in small-plot trials at Prague-Ruzyně in the spring periods 1993–1995. Cultivation included autumn ploughing, spring harrowing and rolling on all plots that were subsequently left to spontaneous weed infestation. Some plots were then mowed or shallowly cultivated in mid-June and late July, others were left without treatment. No significant differences in seedling establishment were found between plots with different treatments. The number of species varied between years, but without a trend to species enrichment or impoverishment. In all years most species were annuals, and species composition did not change in the course of the experiment. The dominant species were Amaranthus retroflexus, Lamium amplexicaule, Echinochloa crus-galli, Chenopodium album, Silene noctiflora and Thlaspi arvense. Species diversity during the experimental years increased due to decreasing dominance of A. retroflexus.

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Effects of application terms of three soil active herbicides on herbicide efficacy and reproductive ability for weeds in maize

Plant Soil and Environment ◽

10.17221/561/2014-pse ◽

2014 ◽

Vol 60 (No. 10) ◽

pp. 452-458 ◽

Cited By ~ 2

Author(s):

J. Andr ◽

V. Hejnák ◽

M. Jursík ◽

V. Fendrychová

Keyword(s):

Seed Production ◽

Yield Loss ◽

Chenopodium Album ◽

Weather Conditions ◽

Field Trials ◽

Amaranthus Retroflexus ◽

Growing Seasons ◽

Reproductive Ability ◽

Average Precipitation ◽

Mercurialis Annua

The aim of this work was to compare herbicide efficacy and reduction of weed reproduction after the application of three frequently used soil residual herbicides during pre-emergent (PRE) and early post-emergent (EPOST) application in maize. Plot field trials were carried out in Central Bohemia during two growing seasons (2010 and 2011). Good efficacy (88%, resp. 83%) was found in isoxaflutole + thiencarbazone (ISF + THC) and terbuthylazin + S-metolachlor (TBA + SMC) on Echinochloa crus-galli, especially in PRE application use. Efficacy on Amaranthus retroflexus was 91% at both tested application periods and there were no significant differences between experimental years. Significant differences in A. retroflexus control were recorded among all tested herbicides (ISF + THC > TBA + SMC > pendimethalin (PEM) + dimethenamid (DMA)). No significant differences between PRE and EPOST were recorded in efficacy on Chenopodium album. Significant differences in efficacy on C. album were recorded among all tested herbicides (ISF + THC > TBA + SMC > PEM + DMA). Mercurialis annua was the most tolerant tested weed, which was significantly better controlled at EPOST herbicide application (73%) compared to PRE application (32%). TBA + SMC showed a significantly higher efficacy on M. annua compared with other tested herbicides. Seed production of all tested weeds was strongly effected by weather conditions, which were significant during 2011, when there was higher than average precipitation during May and June. The most seeds were produced by A. retroflexus > C. album > E. crus-galli > M. annua. ISF + THC best reduced seed production of E. crus-galli, A. retroflexus and C. album, especially when applied at PRE. TBA + SMC best reduced seed production of M. annua. Weed competition on untreated control plots caused yield loss by 90%and 47% in 2011 and 2012, respectively, compared to treatments with the highest yield (ISF + THC).

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A COMPARISON OF MCP AND 2,4-D FOR THE CONTROL OF ANNUAL WEEDS IN GRAIN CROPS

Canadian Journal of Plant Science ◽

10.4141/cjps57-008 ◽

1957 ◽

Vol 37 (1) ◽

pp. 69-83 ◽

Cited By ~ 1

Author(s):

H. A. Friesen ◽

D. R. Walker

Keyword(s):

Chenopodium Album ◽

Amaranthus Retroflexus ◽

Seedling Stage ◽

Dichlorophenoxyacetic Acid ◽

Growth Stages ◽

Thlaspi Arvense ◽

Wild Mustard ◽

The Difference ◽

Lamb’S Quarters ◽

2,4 Dichlorophenoxyacetic Acid

Oats, flax and barley were sprayed with various formulations of MCP (2-methyl-4-chlorophenoxyacetic acid) and 2,4-D (2,4-dichlorophenoxyacetic acid) at a number of Experimental Farms in Western Canada in 1954 and 1955. Each formulation was applied at 4 and 8 ounces of acid equivalent per acre at each of two dates, viz., Date 1, when the weeds were in the seedling stage less than 3 inches in height; and Date 2, at a stage coinciding with the first appearance of buds on the major weed species.Stinkweed (Thlaspi arvense, L.), wild mustard (Brassica kaber (DC.) L.C. Wheeler var. pinnatifida (Stokes) L.C. Wheeler), lamb's quarters (Chenopodium album L.), Russian pigweed (Axyris amarantoides L.), and ball mustard (Neslia paniculata L.), were effectively controlled by each of the MCP and 2,4-D formulations used. Russian thistle (Salsola kali L.), and red-root pigweed (Amaranthus retroflexus L.), were not satisfactorily controlled by MCP, whereas hemp nettle (Galeopsis tetrahit L.) was not controlled by 2,4-D. Wild buckwheat (Polygonum convolvulus L.) was not controlled by any of the treatments. Each treatment was more effective when applied during the seedling stage of the weeds.On the basis of wood control and yield of grain the results of this study favour the use of MCP over 2,4-D with either oats or flax. Oats was significantly more tolerant to MCP, particularly if treated during the early growth stages when weed competition was most critical. With flax, the difference in tolerance was most pronounced in favour of MCP at the later date of treatment. The 2,4-D ester and low volatile ester resulted in a preponderance of plant deformities, lowered the yields of both oats and flax and delayed the maturity of flax significantly. Barley yields in this study were not adversely affected by any of the treatments.

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Sensitivity of sunflower cultivar PR63E82 to tribenuron and propaquizafop in different weather conditions

Plant Soil and Environment ◽

10.17221/343/2018-pse ◽

2018 ◽

Vol 64 (No. 10) ◽

pp. 479-483

Author(s):

Tichý Lukáš ◽

Jursík Miroslav ◽

Kolářová Michaela ◽

Hejnák Václav ◽

Andr Jiří ◽

...

Keyword(s):

Czech Republic ◽

Growth Retardation ◽

Weather Conditions ◽

Field Trials ◽

Ionic Surfactant ◽

Leaf Chlorosis ◽

Herbicide Treatments ◽

Small Plot ◽

Plant Injury

The aim of this work was to verify and assess the tolerance of the PR63E82 (ExpressSun) sunflower cultivar to tribenuron, propaquizafop and their tank-mix combination in two rates under various weather conditions. Three small-plot field trials were carried out on sunflower in Prague, Czech Republic, from 2015 to 2017. High phytotoxicity (25–56%) of tribenuron (TBM) + non-ionic surfactant was observed in 2015 and 2016 when the sunflower was sown in mid-April. In 2017, phytotoxicity was significantly lower (4–6%), probably due to a later sowing of sunflower (May), and hence higher temperatures. The main symptoms of TBM phytotoxicity were leaf chlorosis, necrosis and growth retardation. Propaquizafop (PQF) injury was minimal in 2015 and 2017. A higher phytotoxicity (10–13%) was recorded in 2016, probably due to a hail which occurred 2 days after T2 (second application term (sunflower BBCH 14)) application. Plant injury had puckered leaves and also made more side branches. TBM + PQF damaged sunflower plants most of the tested herbicide treatments (phytotoxicity 3–62%). High phytotoxicity caused stem branching, increased number of sunflower heads and decreased yield.

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AMINO ACID AND PROXIMATE ANALYSES OF WEED SEEDS

Canadian Journal of Plant Science ◽

10.4141/cjps77-033 ◽

1977 ◽

Vol 57 (1) ◽

pp. 243-249 ◽

Cited By ~ 13

Author(s):

RUSSELL TKACHUK ◽

V. JEAN MELLISH

Keyword(s):

Amino Acid ◽

Chenopodium Album ◽

Essential Amino Acids ◽

Amaranthus Retroflexus ◽

Thlaspi Arvense ◽

Wild Mustard ◽

Acid Protein ◽

Weed Seeds ◽

Lamb’S Quarters ◽

Amino Acid Balance

Weed seeds commonly found in Western Canadian cereals and oil seeds as dockage were examined for their amino acid, protein, oil and fiber contents. The weeds analyzed were Sinapis arvenis L.(wild mustard), Thlaspi arvense L. (stinkweed), Descurainia sophia (L.) Webb (flixweed), Polygonum convolvulus L. (wild buckwheat), Rumex pseudonatronatus L. (field dock), Avena fatua L. (wild oats), Setaria viridis (L.) Beauv. (green foxtail), Iva xanthifolia Nutt. (false ragweed), Chenopodium album L. (lamb’s-quarters), and Amaranthus retroflexus L. (redroot pigweed). Composite analysis showed that some of the weed seeds are high in protein and oil content. Amino acid analysis showed that many weeds have an excellent essential amino acid balance, and also a higher content of essential amino acids than do the commonly grown cereals. These results suggest that some weed seeds could be excellent sources of protein and oil for feed or food purposes.

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Early Season Broadleaf Weed Control in Onion

HortScience ◽

10.21273/hortsci.41.4.971d ◽

2006 ◽

Vol 41 (4) ◽

pp. 971D-972

Author(s):

Harlene M. Hatterman-Valenti ◽

Carrie E. Schumacher ◽

Collin P. Auwarter ◽

Paul E. Hendrickson

Keyword(s):

Weed Control ◽

Chenopodium Album ◽

Field Studies ◽

Amaranthus Retroflexus ◽

High Rate ◽

Early Season ◽

Common Lambsquarters ◽

Redroot Pigweed ◽

Herbicide Treatments ◽

Residual Control

Field studies were conducted at Absaraka, Carrington, and Oakes, N.D., in 2005 to evaluate early season broadleaf weed control and onion (Allium cepa L.) injury with herbicides applied preemergence to the crop. DCPA is a common preemergence herbicide used in onion. However, DCPA can be uneconomical in most high-weed situations, or the usage may be restricted due to possible groundwater contamination. Potential substitutes evaluated were bromoxynil, dimethenamid-P, and pendimethalin. Main broadleaf weeds were redroot pigweed (Amaranthus retroflexus L.) and common lambsquarters (Chenopodium album L.). In general, all herbicides, except bromoxynil, provided acceptable broadleaf weed control 4 weeks after treatment. The highest herbicide rate provided greater weed control compared with the lowest rate for each herbicide. However, onion height was also reduced with the highest herbicide rate. In addition, the two highest rates of dimethenamid-P reduced the onion stand compared with the untreated. A postemergence application of bromoxynil + oxyfluorfen + pendimethalin to onion at the four- to five-leaf stage controlled the few broadleaf weeds that escaped the preemergence treatments and provided residual control of mid- and late-season germinating broadleaf weeds at two of the three locations. Intense germination of redroot pigweed during July at the Oakes location reduced onion yield with all treatments compared with the hand-weeded check. In contrast, total onion yields with all herbicide treatments except the high rate of dimethenamid-P were similar to the hand-weeded check at Absaraka and Carrington.

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Weed Management in Transplanted Bell Pepper (Capsicum annuum) with Pretransplant Tank Mixes of Sulfentrazone, S-metolachlor, and Dimethenamid-p

HortScience ◽

10.21273/hortsci.43.5.1492 ◽

2008 ◽

Vol 43 (5) ◽

pp. 1492-1494 ◽

Cited By ~ 9

Author(s):

Darren E. Robinson ◽

Kristen McNaughton ◽

Nader Soltani

Keyword(s):

Weed Management ◽

Chenopodium Album ◽

Fruit Size ◽

Field Trials ◽

Amaranthus Retroflexus ◽

Ambrosia Artemisiifolia ◽

Bell Pepper ◽

Weed Species ◽

Marketable Yield ◽

Excellent Control

Pepper growers currently have limited access to many effective broadleaf herbicides. Field trials were conducted over a 3-year period in Ontario to study the effect of tank mixtures of sulfentrazone (100 or 200 g·ha−1 a.i.) with either s-metolachlor (1200 or 2400 g·ha−1 a.i.) or dimethenamid-p (750 or 1500 g·ha−1 a.i.) on transplanted bell pepper. Under weed-free conditions, there was no visual injury or reduction in plant height, fruit number, fruit size, or marketable yield of transplanted pepper with pretransplant applications of sulfentrazone applied in tank mixtures with s-metolachlor or dimethenamid-p. The tank mixture of sulfentrazone + s-metolachlor gave greater than 85% control of redroot pigweed (Amaranthus retroflexus) and eastern black nightshade (Solanum ptycanthum), but only 70% to 76% control of velvetleaf (Abutilon theophrasti), common ragweed (Ambrosia artemisiifolia), and common lambsquarters (Chenopodium album). The combination of sulfentrazone + dimethenamid-p provided good to excellent control of all weed species except velvetleaf. Based on this study, sulfentrazone and dimethenamid-p have potential for minor use registration in pepper.

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Effect of precipitation on the dissipation, efficacy and selectivity of three chloroacetamide herbicides in sunflower

Plant Soil and Environment ◽

10.17221/750/2012-pse ◽

2013 ◽

Vol 59 (No. 4) ◽

pp. 175-182 ◽

Cited By ~ 11

Author(s):

M. Jursík ◽

M. Kočárek ◽

K. Hamouzová ◽

J. Soukup ◽

V. Venclová

Keyword(s):

Active Ingredient ◽

Field Trial ◽

Chenopodium Album ◽

Soil Layer ◽

Growing Season ◽

Amaranthus Retroflexus ◽

Low Level ◽

Small Plot ◽

Higher Temperature ◽

The Mean

The aim was to compare the efficacy, selectivity to sunflower and dissipation of three chloracetamide herbicides (acetochlor, metolachlor and pethoxamid) in dependence on precipitation after application. A small plot field trial was carried out with sunflower in Central Bohemia in 2010 and 2011. The remaining concentration of active ingredient in the soil of all studied herbicides was lower in the year with a higher temperature and a low level of total natural precipitation at the beginning of the growing season. Higher leaching of metolachlor and pethoxamid was recorded in irrigated plots. No leaching was found in the case of acetochlor. The highest leaching was found for metolachlor (9.2–25.5% in soil layer 5–10 cm). The highest phytotoxicity was found for acetochlor (9.8%) > pethox-amid (4.6%) > metolachlor (1.8%). The mean phytotoxicity in the irrigated plots was 6.9%, compared with 3.9% in the non-irrigated plots. The efficacy of the tested herbicide was affected by wet conditions. The highest efficacy on Chenopodium album, Amaranthus retroflexus, Echinochloa crus-galli and Solanum physalifolium was recorded after application of acetochlor and irrigation.

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Weed Control in Sunflower (Helianthus annuus L.) with Soil-applied Herbicides Affected by a Prolonged and Limited rainfall

Poljoprivreda ◽

10.18047/poljo.27.2.1 ◽

2021 ◽

Vol 27 (2) ◽

pp. 3-14

Author(s):

Zvonko Pacanoski ◽

◽

Arben Mehmeti ◽

Keyword(s):

Weed Control ◽

Chenopodium Album ◽

Field Trials ◽

Early Spring ◽

Amaranthus Retroflexus ◽

Soil Conditions ◽

Weed Species ◽

Polygonum Aviculare ◽

Growing Seasons ◽

Solanum Nigrum L

The field trials were carried out in the Bitola and Titov Veles regions during two sunflower growing seasons (2018 and 2019) to estimate a weed control in sunflower with the soil‒applied herbicides, influenced by a prolonged and limited rainfall. Polygonum aviculare L., Solanum nigrum L., Chenopodium album L., Amaranthus retroflexus L., Portulaca oleracea L., and Echinochloa crus-galli (L.) P. Beauv. were the most dominant weeds in both regions. The efficacy of PRE-em herbicides varied among the weed species, treatments, periods of efficacy estimation, regions, and years. The overall performances of the PRE-em herbicides were correlated with weather and soil conditions. The inconsistent weather patterns between the two years of the study likely influenced the weed control. All weeds in 2018 in the Bitola region were poorly controlled (<77% and <62%, 28 and 56 days after application, respectively) due to a higher amount of rainfall (57 mm) during the 10 days of the 1st decade after herbicide application. The herbicide efficacy has only produced a marginal control of weeds in 2019 in the Titov Veles region as well (<68% and <59%, 28 and 56 days after application, respectively), due to the drought conditions observed in this region in early spring and in mid-spring. A PREem application followed by a heavy rainfall resulted in a sunflower injury in the Bitola region in 2018, ranging from 9 to 28% across the PRE-em treatments seven days after emergence. The injuries by oxyfluorfen and dimethenamid-P were more serious (24 and 28%, respectively). The sunflower achene yields for each treatment in both regions generally reflected an overall weed control and crop injury.

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Replace of the EPOST glyphosate with pre herbicides and application of different LPOST glyphosate rates for weed control in established vineyard

Acta agriculturae Slovenica ◽

10.14720/aas.2020.116.2.1910 ◽

2020 ◽

Vol 116 (2) ◽

pp. 299

Author(s):

Zvonko PACANOSKI ◽

Krum BOŠKOV ◽

Arben Beni MEHMETI

Keyword(s):

Weed Control ◽

Cynodon Dactylon ◽

Lolium Multiflorum ◽

Chenopodium Album ◽

Field Trials ◽

Early Summer ◽

Xanthium Strumarium ◽

Summer Period ◽

Herbicide Treatments ◽

Annual Weeds

Two-year field trials were conducted at two winegrowing districts (Kavadarci and Skopje in 2016 and 2017) to evaluate wheather oxyfluorfen, pendimethalin and flazasulfuron can replace early post-emergence (EPOST) application of glyphosate in established vineyard until its application in early summer period. The weed vegetation in vineyards in both years was consisted mainly of Chenopodium album L., Setaria viridis (L). Beauv., Papaver rhoeas L., Xanthium strumarium L., Lolium multiflorum Lam., Sorghum halepense (L.) Pers. and Cynodon dactylon (L.) Pers. Pendimethalin, oxyfluorfen and flazasulfuron efficiently reduced predominant annual weeds and S. halepense seedlings in 2017, but not in 2016. PRE herbicides, regardless year, had no significant effect on C. dactylon. Opposite, the efficacy of EPOST applied glyphosate was significantly lower in 2017 compared to 2016. LPOST glyphosate applied at 2.0 l ha-1 provided at least 94 % control of dominant annual broadleaf and grass weeds. LPOST application of glyphosate at 2.0 l ha-1 and glyphosate at 2.0 and 4.0 l ha-1 resulted in unsatisfactory weed control of predominant perennial S. halepense, and C. dactylon, respectively. LPOST glyphosate applied at 4.0 l ha-1 provided control of S. halepense by 84 % or more. LPOST glyphosate applied at 8.0 l ha-1 reduced the amount of S. halepense and C. dactylon at least 97 %. Grapevine yield of both varieties was not lower in all herbicide treatments in 2016 compared with 2017. However, yield in the PRE herbicide treatments fb 2.0 and 4.0 l ha-1 glyphosate was collectively 15-19 % and 17-19 % lower compare to PRE herbicide treatments fb 8.0 l ha-1 glyphosate and standard two applications of glyphosate, respectively for both years and districts. No impacts to grapevine growth were observed from PRE herbicide treatments at either district

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