Influence of Herbicides on the Development of Internal Necrosis of Sweetpotato

Field studies were conducted to determine the influence of herbicides on the development of internal necrosis (IN) in sweetpotato storage roots. In a slip propagation study, herbicide treatments included PRE application (immediately after covering seed roots with soil) of clomazone (0.42, 0.84 kg ai ha-1), flumioxazin (0.11, 0.21 kg ai ha-1), fomesafen (0.28, 0.56 kg ai ha-1), linuron (0.56, 1.12 kg ai ha-1),S-metolachlor (0.8, 1.6 kg ai ha-1), flumioxazin plusS-metolachlor (0.11 + 0.8 or 1.6 kg ha-1), and napropamide (1.12, 2.24 kg ai ha-1), and POST application (2 to 4 wk prior to cutting slips) of ethephon (0.84, 1.26 kg ai ha-1) and paraquat (0.14, 0.28 kg ai ha-1). In a field production study, flumioxazin, fomesafen, linuron, and paraquat were applied PREPLANT (one d prior to sweetpotato transplanting), clomazone,S-metolachlor, and napropamide were applied PRE [4 d after transplanting (DAP)], flumioxazin PREPLANT followed by (fb) S-metolachlor PRE, and ethephon applied POST (2 wk prior to harvest). Herbicide rates were similar to those used in the slip propagation study. Yield of sweetpotato in both studies was not affected by herbicide treatment. In both studies, IN incidence and severity increased with time and was greatest at 60 d after curing. No difference was observed between herbicide treatments for IN incidence and severity in the slip production study which indicates herbicide application at time of slip propagation does not impact the development of IN. In the field production study, the only treatment that increased IN incidence compared to the nontreated was ethephon with 53% and 2.3 incidence and severity, respectively. The presence of IN affected roots in nontreated plots indicates that some other pre- or post-curing factors other than herbicides are responsible for the development of IN. However, the ethephon application prior to sweetpotato root harvest escalates the development of IN.

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Effect of Herbicides on Soybean Thrips (Sericothrips variabilis) in Soybeans (Glycine max)

Weed Technology ◽

10.1017/s0890037x00025793 ◽

1990 ◽

Vol 4 (3) ◽

pp. 475-477 ◽

Cited By ~ 4

Author(s):

R. M. Huckaba ◽

H. D. Coble

Keyword(s):

Glycine Max ◽

Field Studies ◽

The Other ◽

Herbicide Treatment ◽

Herbicide Treatments ◽

Soybean Thrips

Field studies were conducted to determine the effect of several herbicides on soybean thrips numbers in soybean. Adult soybean thrips numbers in the preplant-incorporated and preemergent herbicide treatments were observed to be either greater than or equal to, but never less than, numbers in the control plots. Larval soybean thrips numbers were not observed to be affected by the preplant-incorporated or preemergent treatments. The postemergence herbicide treatment of naptalam plus dinoseb consistently reduced both adult and larval soybean thrips numbers. The other postemergent treatments did not affect numbers consistently.

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Response of flax and lentil to seeding rates, depths and spring application of dinitroanaline herbicides

Canadian Journal of Plant Science ◽

10.4141/cjps94-159 ◽

1994 ◽

Vol 74 (4) ◽

pp. 875-882 ◽

Cited By ~ 6

Author(s):

D. A. Wall

Keyword(s):

Population Density ◽

Seed Yield ◽

Linum Usitatissimum ◽

Field Studies ◽

Test Weight ◽

Seeding Rate ◽

Population Densities ◽

Herbicide Treatment ◽

Herbicide Treatments ◽

One Year

Two field studies were conducted at Morden, Manitoba in 1992 and 1993 to investigate the effect of seeding depth and seeding rate on flax and lentil recovery following spring application of dinitroanaline herbicides. In the first study, the effect of seeding depth on flax and lentil tolerance to ethalfluralin, pendimethalin and trifluralin, applied preplant soil incorporated at 1.1 kg a.i. ha−1 in the spring, was investigated. Deep seeding (6 cm) reduced flax population density by 59%, averaged over 2 yr, when compared with shallow seeding (3 cm). Ethalfluralin, pendimethalin and trifluralin, reduced flax population density, but the effect of herbicide was less when flax was seeded shallow. Trifluralin and ethalfluralin reduced flax yield more when the crop was seeded deep than when seeded shallow. Herbicide treatments had no effect on flax yield when the crop was seeded shallow. Ethalfluralin and trifluralin reduced lentil population density and seed yield in one year only. Pendimethalin did not reduce lentil population density or seed yield. Deep seeding did not affect lentil population density, seed yield or phytotoxicity of dinitroanalines in this crop. In a second study, flax and lentil were seeded at 15, 30, 45, 60 and 90 kg ha−1 at 3 and 6 cm planting depths to assess the effect of seeding depth and seeding rate on crop recovery following spring application of ethalfluralin. In ethalfluralin treated plots, seeding rate had to be increased from 60 to > 90 kg ha−1 to achieve similar population densities as 45 kg ha−1 in untreated plots. Flax yields were unaffected by ethalfluralin when the crop was seeded shallow, but yields were reduced significantly when the crop was seeded deep. Lentil population density increased linearly with seeding rate. Lentil population density was unaffected by seeding depth or herbicide treatment. Ethalfluralin did not reduce lentil yield in either year. Lentil yields increased with seeding rate up to 30 kg ha−1, with little further increase in yield for seeding rates between 30 and 90 kg ha−1. Key words:Lens culinaris, Linum usitatissimum, population density, seeding depth, seeding rate, yield, seed test weight, ethalfluralin, pendimethalin, trifluralin

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Weed Control in Glyphosate-Resistant Corn as Affected by Preemergence Herbicide and Timing of Postemergence Herbicide Application

Weed Technology ◽

10.1614/wt-04-288r.1 ◽

2006 ◽

Vol 20 (3) ◽

pp. 564-570 ◽

Cited By ~ 23

Author(s):

Robert G. Parker ◽

Alan C. York ◽

David L. Jordan

Keyword(s):

Grain Yield ◽

Weed Control ◽

Field Studies ◽

Herbicide Application ◽

Application Timing ◽

Common Lambsquarters ◽

Herbicide Treatments ◽

Prickly Sida ◽

Smooth Pigweed ◽

Or Applications

Field studies were conducted at three locations during both 2002 and 2003 to evaluate weed control and response of glyphosate-resistant (GR) corn to glyphosate or nicosulfuron plus atrazine applied POST at three application timings with and without alachlor plus atrazine applied PRE. The POST herbicides were applied timely (5- to 9-cm weeds) or applications were delayed 1 or 2 wk. All treatments, except the weedy check, were followed by glyphosate postemergence-directed (PDIR) 4 wk after the timely POST application. Common lambsquarters, common ragweed, Palmer amaranth, prickly sida, and smooth pigweed were controlled at least 94% regardless of PRE or POST treatments. Large crabgrass and fall panicum were controlled at least 96% by glyphosate regardless of PRE herbicide or POST application timing. In contrast, control by nicosulfuron plus atrazine POST in the absence of PRE herbicide decreased as application was delayed. Sicklepod was controlled at least 94% when POST herbicides were applied timely, but control by both POST herbicide treatments decreased with delayed application regardless of PRE herbicide. Tall morningglory was controlled 93% or greater by POST herbicides applied timely. Control by both POST herbicide treatments decreased as application was delayed, with glyphosate being affected more by timing than nicosulfuron plus atrazine. Corn grain yield was similar with glyphosate and nicosulfuron plus atrazine. Yield was unaffected by POST application timing when PRE herbicides were included. Without PRE herbicide, grain yield decreased as POST herbicide application was delayed.

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Preemergence Herbicides plus Postemergence Chloroxuron on Soybeans

Weed Science ◽

10.1017/s0043174500078723 ◽

1972 ◽

Vol 20 (6) ◽

pp. 548-553 ◽

Cited By ~ 7

Author(s):

J. V. Parochetti ◽

R. W. Feeny ◽

S. R. Colby

Keyword(s):

Glycine Max ◽

Weed Control ◽

Field Studies ◽

Ipomoea Purpurea ◽

The Third ◽

Herbicide Treatment ◽

Herbicide Treatments ◽

Preemergence Herbicides

Greenhouse and field studies were conducted with 3-[p-(p-chlorophenoxy)phenyl]-1,1-dimethylurea (chloroxuron). Tolerant soybean(Glycine max(L.) Merr.) and susceptible tall morningglory(Ipomoea purpurea(L.) Roth.) and ivyleaf morningglory(I. hederacea(L.) Jacq.) were studied with both root and foliar chloroxuron applications. Soybean tolerance to chloroxuron was reduced when treatments occurred in the unifoliate stage; greatest soybean tolerance was noted when soybeans were treated in either the cotyledonary or third trifoliage stage. Tall and ivyleaf morningglory were susceptible to chloroxuron until about 21 days of age (five true leaves), after which resistance increased. Root applications of chloroxuron were more phytotoxic than foliar applications for soybeans and both species of morningglory. In a 3-year study in the field, the following sequential herbicide treatments of either α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine (trifluralin), 4-(methylsulfonyl-2,6-dinitro-N,N-dipropylaniline (nitralin),S-propyl dipropylthiocarbamte (vernolate), or 3-(3,4-dichlorophenyl)-1-methoxy-1-methylurea (linuron) applied preemergence plus chloroxuron postemergence resulted in higher soybean yields than any single herbicide treatment. Weed control was better with the sequential combinations. All sequential combinations with chloroxuron caused soybean injury. Greatest soybean injury occurred when chloroxuron was applied in the first and second trifoliate stage than in the third trifoliate stage. Vernolate alone caused some injury in certain years.

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Phytotoxicity and Weed Control Efficacy of Three Non-labeled Herbicides for Field-grown Hemerocallis spp.

HortScience ◽

10.21273/hortsci.39.4.745d ◽

2004 ◽

Vol 39 (4) ◽

pp. 745D-745

Author(s):

Patricia R. Knight* ◽

Christine E. Coker ◽

Benedict Posadas ◽

John M. Anderson

Keyword(s):

Weed Control ◽

Control Treatment ◽

Separate Experiment ◽

Control Efficacy ◽

Random Design ◽

Herbicide Treatment ◽

Herbicide Treatments ◽

Number Percentage ◽

Field Production

The IR-4 program works to identify potential minor-use horticultural chemicals and evaluate them for phytotoxicity and efficacy. The objective of this experiment was to evaluate phytotoxicity and weed control of three unlabeled herbicides on field production of Hemerocallis spp. `Ming Toy'. Ten-cm pots of `Ming Toy' were planted into the field 16 July 2001. Each plot consisted of 3 plants per treatment with 6 replications in a completely random design. Each herbicide was analyzed as a separate experiment. Herbicide treatments consisted of clopyralid (0.14, 0.28, 0.56, or 1.1 kg·ha-1 a.i.), clethodim (125, 250, or 500 mL·L-1 a.i.), or bentazon (1.1, 2.2, or 4.4 kg·ha-1 a.i.). Data collected included weed number, percentage of weed coverage (% weed coverage), and phytotoxicity and foliar color ratings for `Ming Toy'. Clopyralid reduced total weed number 90 DAT although % weed coverage was similar or worse compared to the control treatment. Phytotoxicity 90 DAT was not significant for plants treated with clopyralid, but foliar color ratings were reduced. Application of clethodim to `Ming Toy' plots, regardless of rate, resulted in similar weed numbers compared to the control 49 DAT. Clethodim application, regardless of rate, reduced % weed coverage compared to the control treatment. Phytotoxicity 90 DAT was not significant, regardless of herbicide treatment, but foliar color ratings were lower for herbicide treated plants compared to the control. Bentazon, regardless of rate, reduced weed number and % weed coverage 49 DAT compared to the control. Phytotoxicity was similar to the control for plants treated with 1.1 kg·ha-1 a.i.

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Vine Removal Prior to Harvest, and Curing Duration and Temperature Affect the Incidence and Severity of Internal Necrosis in ‘Covington’ Sweetpotato

HortTechnology ◽

10.21273/horttech04408-19 ◽

2020 ◽

Vol 30 (5) ◽

pp. 544-551

Author(s):

Fernando Montero de Espinosa Baselga ◽

Jonathan R. Schultheis ◽

Michael D. Boyette ◽

Lina M. Quesada-Ocampo ◽

Keith D. Starke ◽

...

Keyword(s):

Ipomoea Batatas ◽

Field Studies ◽

Curing Temperature ◽

Storage Roots ◽

Physiological Disorder ◽

Potash Fertilizer ◽

Storage Room ◽

Postharvest Treatments ◽

Internal Necrosis ◽

Lower Temperature

Internal necrosis (IN) is a physiological disorder that affects Covington, the most commonly grown sweetpotato (Ipomoea batatas) cultivar in North Carolina. Because IN affects the quality of sweetpotato storage roots, studies have been conducted since the first report of IN in 2006. Field studies (three in 2016 and two in 2017) were conducted to evaluate preharvest and postharvest treatments on the occurrence of IN in ‘Covington’ storage roots. Four preharvest treatments consisted of combinations of high chlorine or minimal chlorine potash fertilizer and mowing vs. not mowing before harvest. For postharvest treatments, 30 storage roots were obtained at harvest from each preharvest treatment plot and immediately cured in 75 and 85 °F rooms for a duration of 0.5, 1, 2, 3, and 5 weeks in 2016, and 0.5, 1, and 2 weeks in 2017. Shorter curing durations (0.5 and 1 week) coincided with industry recommendations while longer durations mimicked the challenges that some commercial facilities face when cooling down temperatures of rooms after curing is supposed to be concluded. Once curing temperature and curing duration treatments were completed, roots were placed in a 58 °F storage room at 85% relative humidity until cut. A control comparison was included in which harvested roots were placed in a 58 °F storage room (no curing) immediately after harvest. The storage roots from all temperature treatments were then cut 49 to 80 days after harvest, and incidence and severity of IN visually rated. Preharvest potash fertilizer treatments had minimal or no effect on occurrence of IN. However, mowing vines before harvest in several studies reduced IN incidence when roots were cured for more than 0.5 week at temperatures of at least 75 °F. Lower temperature (75 vs. 85 °F) and shorter curing duration (0.5 vs. 1, 2, 3, or 5 weeks) resulted in reduced IN occurrence in ‘Covington’ sweetpotato.

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Timing of Chlorimuron and Imazaquin Application for Weed Control in No-Till Soybeans (Glycine max)

Weed Science ◽

10.1017/s0043174500071538 ◽

1991 ◽

Vol 39 (2) ◽

pp. 232-237 ◽

Cited By ~ 24

Author(s):

J. Boyd Carey ◽

Michael S. Defelice

Keyword(s):

Weed Control ◽

Field Studies ◽

Row Spacing ◽

Herbicide Application ◽

Poor Control ◽

Application Timing ◽

Common Lambsquarters ◽

No Till ◽

Giant Foxtail ◽

Herbicide Treatments

Field studies were conducted to evaluate the influence of herbicide application timing on weed control in no-till soybean production. Row spacing generally had no effect on weed control. Herbicide treatments containing chlorimuron plus metribuzin applied as many as 45 days prior to planting in 1988 and 1989 controlled broadleaf weeds throughout the growing season. Imazaquin applied 45 and 30 days prior to planting provided poor control of common cocklebur in 1989. Giant foxtail control was inconsistent with all herbicide treatments. Soybean yields subsequent to early preplant herbicide applications were greater than or equal to those in which applications were made at planting when late-season weed control was adequate. Herbicides applied preemergence did not control high densities of common lambsquarters in 1989.

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Impact of postemergence herbicides on soybean injury and canopy formation

Weed Technology ◽

10.1017/wet.2020.55 ◽

2020 ◽

Vol 34 (5) ◽

pp. 727-734

Author(s):

Grant L. Priess ◽

Jason K. Norsworthy ◽

Trenton L. Roberts ◽

Edward E. Gbur

Keyword(s):

Growth Stage ◽

Yield Loss ◽

Soil Surface ◽

Growing Season ◽

Field Studies ◽

Herbicide Application ◽

Canopy Volume ◽

Herbicide Treatments ◽

Soybean Canopy ◽

Postemergence Herbicides

AbstractField studies were conducted in 2017 and 2018 in Arkansas to evaluate the injury caused by herbicides on soybean canopy formation and yield. Fomesafen, acifluorfen, S-metolachlor + fomesafen, and S-metolachlor + fomesafen + chlorimuron alone and in combination with glufosinate were applied to glufosinate-resistant soybean at the V2 growth stage. Soybean injury resulting from these labeled herbicide treatments ranged from 9% to 25% at 2 wk after application. This level of injury resulted in a 4-, 5-, 6-, and 6-d delay in soybean reaching 80% groundcover following fomesafen, acifluorfen, S-metolachlor + fomesafen, and S-metolachlor + fomesafen + chlorimuron, respectively. There was a 2-d delay in soybean reaching a canopy volume of 15,000 cm3 following each of the four herbicide treatments. The addition of glufosinate to the herbicide applications resulted in longer delays in canopy formation with every herbicide treatment except glufosinate + fomesafen. Fomesafen, acifluorfen, S-metolachlor + fomesafen, and S-metolachlor + fomesafen + chlorimuron, each applied with glufosinate, delayed soybean from reaching 80% groundcover by 2, 7, 8, and 9 d, respectively, and delayed the number of days for soybean to reach a canopy volume of 15,000 cm3 by 2, 3, 2, and 2 d, respectively. No yield loss occurred with any herbicide application. A delay in percent groundcover in soybean allows sunlight to reach the soil surface for longer periods throughout the growing season, possibly promoting late-season weed germination and the need for an additional POST herbicide application.

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Influence of Residual Herbicides on Rate of Paraquat and Glyphosate in Stale Seedbed Soybean (Glycine max)

Weed Technology ◽

10.1017/s0890037x00038082 ◽

1993 ◽

Vol 7 (4) ◽

pp. 960-965 ◽

Cited By ~ 5

Author(s):

Andrew J. Lanie ◽

James L. Griffin ◽

Daniel B. Reynolds ◽

P. Roy Vidrine

Keyword(s):

Glycine Max ◽

Weed Control ◽

Field Studies ◽

Soybean Yield ◽

Herbicide Treatment ◽

Herbicide Treatments ◽

Hemp Sesbania ◽

Prickly Sida ◽

Residual Herbicide ◽

Control Tank

Field studies were conducted to evaluate weed control with paraquat and glyphosate applied at various rates alone and in combination with residual herbicides. Morningglory, prickly sida, and hemp sesbania control 28 d after treatment was similar regardless of herbicide treatment. In contrast, barnyardgrass control when paraquat was tank mixed with pendimethalin plus imazaquin was equal to that of paraquat alone but less than that for tank mixtures with metolachlor plus metribuzin plus chlorimuron or metolachlor plus metribuzin. Barnyardgrass control and soybean yield when paraquat was applied at 1050 g ai/ha in combination with metolachlor plus metribuzin plus chlorimuron or metolachlor plus metribuzin was greater than when the same residual herbicide treatments were applied with paraquat at 350 g/ha. Yield following glyphosate at 840 and 1120 g ai/ha in combination with residual herbicides was no greater than when glyphosate was applied alone, which was reflective of barnyardgrass control. Tank mixtures of glyphosate at 1680 g/ha with metolachlor plus metribuzin plus chlorimuron or metolachlor plus metribuzin resulted in soybean yield higher than for glyphosate alone. Regardless of the glyphosate and residual herbicide combination, soybean yield was no greater than when paraquat was applied at 350 g/ha in combination with metolachlor plus metribuzin plus chlorimuron.

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Johnsongrass (Sorghum halepense) Control with Imazethapyr and Haloxyfop in Conventional and Vertical-tilled Soybean (Glycine max)

Weed Science ◽

10.1017/s004317450009398x ◽

1996 ◽

Vol 44 (2) ◽

pp. 345-349 ◽

Cited By ~ 2

Author(s):

Hector J. Tassara ◽

Jose Santoro ◽

Mircza C. De Seiler ◽

Esteban Bojanich ◽

Claudio Rubione ◽

...

Keyword(s):

Leaf Area ◽

Growing Season ◽

Field Studies ◽

Sorghum Halepense ◽

Herbicide Application ◽

Growing Seasons ◽

Reduced Frequency ◽

Herbicide Treatments ◽

Tillage System ◽

Measuring Frequency

Field studies in conventional and vertical-tilled soybeans were conducted in 1992/93 and 1993/94 at four locations in Argentina to compare the efficacy of imazethapyr and haloxyfop for johnsongrass control. Control was evaluated by measuring frequency of johnsongrass-infested areas at the beginning of the 1992/93 and 1993/94 growing seasons. Relative johnsongrass leaf area and number of rhizome phytomers within infested areas also was evaluated. Herbicide application reduced frequency of infested areas in the 1992/93 growing season. Frequency of infested areas increased in check plots. No differences were found among herbicide treatments, suggesting that the effect of imazethapyr was as high as that observed for specific graminicides. Reduction in frequency of infested areas caused by herbicide treatments was accompanied to some extent by a decrease in intensity of infestation within infested patches assessed by measuring johnsongrass relative leaf area. Phytomer population levels, on the other hand, were reduced only after two consecutive years of herbicide application. No differences were found among herbicide treatments in terms of impact on both measures of weed abundance. Johnsongrass responded similarly to all treatments regardless of tillage system.

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