Weed TechnologyPub Date : 2023-05-22DOI: 10.1017/wet.2023.26
Erika J. Haug, A. Howell, Benjamin P. Sperry, C. Mudge, R. Richardson, K. Getsinger
{"title":"Simulated herbicide spray retention of commonly managed invasive emergent aquatic macrophytes","authors":"Erika J. Haug, A. Howell, Benjamin P. Sperry, C. Mudge, R. Richardson, K. Getsinger","doi":"10.1017/wet.2023.26","DOIUrl":"https://doi.org/10.1017/wet.2023.26","url":null,"abstract":"Abstract Invasive emergent and floating macrophytes can have detrimental impacts on aquatic ecosystems. Management of these aquatic weeds frequently relies upon foliar application of aquatic herbicides. However, there is inherent variability of overspray (herbicide loss) for foliar applications into waters within and adjacent to the targeted treatment area. The spray retention (tracer dye captured) of four invasive broadleaf emergent species (water hyacinth, alligatorweed, creeping water primrose, and parrotfeather) and two emergent grass-like weeds (cattail and torpedograss) were evaluated. For all species, spray retention was simulated using foliar applications of rhodamine WT (RWT) dye as a herbicide surrogate under controlled mesocosm conditions. Spray retention of the broadleaf species was first evaluated using a CO2-pressurized spray chamber overtop dense vegetation growth or no plants (positive control) at a greenhouse (GH) scale. Broadleaf species and grass-like species were then evaluated in larger outdoor mesocosms (OM). These applications were made using a CO2-pressurized backpack sprayer. Evaluation metrics included species-wise canopy cover and height influence on in-water RWT concentration using image analysis and modeling techniques. Results indicated spray retention was greatest for water hyacinth (GH, 64.7 ± 7.4; OM, 76.1 ± 3.8). Spray retention values were similar among the three sprawling marginal species alligatorweed (GH, 37.5 ± 4.5; OM, 42 ± 5.7), creeping water primrose (GH, 54.9 ± 7.2; OM, 52.7 ± 5.7), and parrotfeather (GH, 48.2 ± 2.3; OM, 47.2 ± 3.5). Canopy cover and height were strongly correlated with spray retention for broadleaf species and less strongly correlated for grass-like species. Although torpedograss and cattail were similar in percent foliar coverage, they differed in percent spray retention (OM, 8.5± 2.3 and 28.9 ±4.1, respectively). The upright leaf architecture of the grass-like species likely influenced the lower spray retention values in comparison to the broadleaf species. Nomenclature: Alligatorweed; Alternanthera philoxeroides (Mart.) Griseb.; cattail; Typha latifolia L.; creeping water primrose; Ludwigia grandiflora (Michx.) Greuter & Burdet; parrotfeather; Myriophyllum aquaticum (Vell.) Verdc.; torpedograss Panicum repens L.; water hyacinth; Eichhornia crassipes (Mart.) Solms","PeriodicalId":23710,"journal":{"name":"Weed Technology","volume":"37 1","pages":"243 - 250"},"PeriodicalIF":1.4,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43904518","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Weed TechnologyPub Date : 2023-05-15DOI: 10.1017/wet.2023.30
T. Bean, S. Stoddard, L. Sosnoskie, A. Osipitan, P. Devkota, Guy B. Kyser, B. Hanson
{"title":"Herbicide screening for weed control and crop safety in California melon production","authors":"T. Bean, S. Stoddard, L. Sosnoskie, A. Osipitan, P. Devkota, Guy B. Kyser, B. Hanson","doi":"10.1017/wet.2023.30","DOIUrl":"https://doi.org/10.1017/wet.2023.30","url":null,"abstract":"Abstract Weed management in cantaloupe and other melon crops is important to maximize fruit yield; however, there are few registered herbicides available in California. Several independent herbicide trials were conducted at University of California field stations in Davis (Yolo County), Five Points (Fresno County), and Holtville (Imperial County) from 2013 to 2019 to evaluate both registered and unregistered herbicides and incorporation methods (sprinklers, cultivation, or none) for crop safety and weed control in melons. Although specific treatments varied among locations depending on local practice and research objectives, ethalfluralin and halosulfuron were used in all experiments, and bensulide and S-metolachlor were evaluated in 4 of 6 site-years. Additional herbicides included clethodim, clomazone, DCPA, napropamide, pendimethalin, sethoxydim, and sulfentrazone. Among registered herbicides, halosulfuron, halosulfuron + ethalfluralin, and ethalfluralin + bensulide combinations provided consistently beneficial weed control across all site-years compared to the nontreated control. S-metolachlor performed as well as the best of the registered herbicides tested at each site-year; although moderate injury was noted at the Davis location, this did not reduce melon yield. The method used to incorporate preplant herbicides had a significant impact on weed control efficacy but varied by location. Mechanical incorporation of preplant herbicides resulted in improved weed control and yield compared to sprinklers. Early-season weed control, whether by herbicides or hand weeding, resulted in significant yield increase in most site-years. Nomenclature: Bensulide; clethodim; clomazone; DCPA; ethalfluralin; halosulfuron; napropamide; pendimethalin; S-metolachlor; sethoxydim; sulfentrazone; cantaloupe, Cucumis melo L.","PeriodicalId":23710,"journal":{"name":"Weed Technology","volume":"37 1","pages":"259 - 266"},"PeriodicalIF":1.4,"publicationDate":"2023-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45583089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Weed TechnologyPub Date : 2023-05-08DOI: 10.1017/wet.2023.28
Thierry E. Besançon, Wesley Bouchelle
{"title":"Weed control and highbush blueberry tolerance with indaziflam on sandy soils","authors":"Thierry E. Besançon, Wesley Bouchelle","doi":"10.1017/wet.2023.28","DOIUrl":"https://doi.org/10.1017/wet.2023.28","url":null,"abstract":"Abstract Northern highbush blueberry is an important fresh market product in New Jersey where the plant was first domesticated in the early 20th century. Because of the short period for safely and timely applying postemergence (POST) herbicides, reliance on residual herbicides that provide season-long control of weeds is essential for blueberry growers to minimize the detrimental effect of weed competition on berry yield and quality and bush growth. Field studies were conducted from 2018 to 2020 in Chatsworth, New Jersey, on ‘Bluecrop’, ‘Duke’, and ‘Elliott’ blueberry cultivars growing on sandy acidic soil to evaluate weed control and crop tolerance in response to repeated annual applications of indaziflam at 73 or 146 g ai ha–1 applied in fall or spring. The efficacy of indaziflam treatments were compared to those of fall-applied dichlobenil at 3,300 g ai ha–1 or a spring-applied mix of diuron at 1,800 g ai ha–1, oryzalin at 3,360 g ai ha–1, and mesotrione at 210 g ai ha–1. Indaziflam at the currently labeled rate of 73 g ai ha–1 provided ≥85% and season-long control of horseweed, Canadian toadflax, and large crabgrass with fall applications on dormant blueberry, whereas spring applications were less effective. Whereas minor (≤8%) and transient leaf crinkling was noted in response to spring-applied indaziflam at 146 g ai ha–1, a fall application never caused leaf crinkling greater than that observed in the nontreated weedy and weed-free controls, regardless of rate. No negative effects on plant growth or fruit production were observed from indaziflam applied at 73 or 146 g ai ha–1 in fall or spring. Findings of this study suggest that indaziflam applied at 73 (1× commercial use rate) and 146 g ai ha–1 is safe to use on blueberry grown on New Jersey sandy acidic soils despite restrictions for using this herbicide on such soils. Nomenclature: Dichlobenil; diuron; indaziflam; mesotrione; oryzalin; American burnweed Erechtites hieraciifolius (L.) Raf. ex DC.; carpetweed, Mollugo verticillata (L.); horseweed, Conyza canadensis (L.) Cronquist; large crabgrass, Digitaria sanguinalis (L.) Scop.; narrowleaf goldentop, Euthamia caroliniana (L.) Green ex Porter & Britton; Canada toadflax, Nuttallanthus canadensis (L.) D.A. Sutton; Pine Barren flatsedge, Cyperus retrorsus Chapm; northern highbush blueberry, Vaccinium corymbosum L.","PeriodicalId":23710,"journal":{"name":"Weed Technology","volume":"37 1","pages":"213 - 220"},"PeriodicalIF":1.4,"publicationDate":"2023-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43298583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Weed TechnologyPub Date : 2023-05-08DOI: 10.1017/wet.2023.29
Hannah E. Symington, N. Soltani, Allan C. Kaastra, D. Hooker, D. Robinson, P. Sikkema
{"title":"Multiple herbicide-resistant waterhemp control with Group 15 herbicides","authors":"Hannah E. Symington, N. Soltani, Allan C. Kaastra, D. Hooker, D. Robinson, P. Sikkema","doi":"10.1017/wet.2023.29","DOIUrl":"https://doi.org/10.1017/wet.2023.29","url":null,"abstract":"Abstract Waterhemp has evolved resistance to seven herbicide modes of action in the United States and to five in Canada, which limits weed control options for producers. The objective of this research was to quantify the level and duration of residual control of multiple herbicide-resistant (MHR) waterhemp with five Group 15 herbicides (acetochlor, dimethenamid-p, flufenacet, pyroxasulfone, and S-metolachlor) applied preemergence in a non-crop area. Four field trials were conducted over a 2-yr period (2021, 2022) in southwestern Ontario, Canada. By 4 wk after application (WAA) 91% of waterhemp had emerged in the nontreated control area. The numerical control of waterhemp with all Group 15 herbicides, with the exception of pyroxasulfone, was greatest at 4 WAA, then control declined. Flufenacet provided the lowest waterhemp control; dimethenamid-p and S-metolachlor provided intermediate control, and acetochlor and pyroxasulfone provided the highest control. Waterhemp control with pyroxasulfone peaked at 6 WAA with 99% and declined to 77% at 12 WAA. Flufenacet (low and high rates) was predicted to reduce waterhemp emergence by 50% for 42 to 44 d after application (DAA). Dimethenamid-p, S-metolachlor, and acetochlor (both formulations and three rates) were predicted to reduce waterhemp emergence by 80% for 36, 43, and 33 to 51 DAA, respectively; in contrast, pyroxasulfone was predicted to reduce waterhemp emergence by 80% for 82 DAA. This study concludes that of the Group 15 herbicides evaluated, flufenacet provides the lowest and shortest residual control of waterhemp, and pyroxasulfone provides the highest and longest residual control of waterhemp. Nomenclature: Giant foxtail; Setaria faberi Herrm.; pigweed; Amaranthus spp.; velvetleaf; Abutilon theophrasti Medik.; waterhemp; Amaranthus tuberculatus (Moq.) J.D. Sauer; woolly cupgrass; Eriochloa villosa (Thunb.) Kunth.","PeriodicalId":23710,"journal":{"name":"Weed Technology","volume":"37 1","pages":"251 - 258"},"PeriodicalIF":1.4,"publicationDate":"2023-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45223897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Weed TechnologyPub Date : 2023-04-13DOI: 10.1017/wet.2023.24
V. Choudhary, S. S. Reddy, Subhash K. Mishra, Y. Gharde, Sunil Kumar, M. Yadav, S. Barik, P.K. Singh
{"title":"First report on ALS herbicide resistance in barnyardgrass (Echinochloa crus-galli) from rice fields of India","authors":"V. Choudhary, S. S. Reddy, Subhash K. Mishra, Y. Gharde, Sunil Kumar, M. Yadav, S. Barik, P.K. Singh","doi":"10.1017/wet.2023.24","DOIUrl":"https://doi.org/10.1017/wet.2023.24","url":null,"abstract":"Abstract Bispyribac-sodium, a herbicide that inhibits acetolactate synthase (ALS), is frequently used in rice fields in India to control weeds, including the most common noxious weed, barnyardgrass. However, rice growers have recently reported reduced control of barnyardgrass with bispyribac-sodium. Hence, a large-scale survey was carried out to assess bispyribac-sodium resistance in Chhattisgarh and Kerala, two rice-growing states. Open-field pot experiments were conducted for 2 yr to confirm resistance to bispyribac-sodium. Of the 37 biotypes tested, 30% (11) survived the recommended label rate of bispyribac-sodium (25 g ai ha–1). The effective rate of bispyribac-sodium required to achieve 50% control (ED50) of putative resistant biotypes ranged from 18 to 41 g ha–1, whereas it was about 10 g ha–1 for susceptible biotypes. This suggests that putative biotypes were two to four times more resistant to bispyribac-sodium. At 6 d after herbicide application, an in vitro enzyme assay demonstrated higher ALS enzyme activity in putative resistant biotypes (66% to 75%) compared with susceptible biotypes (48% to 52%). This indicates the presence of an insensitive ALS enzyme in those biotypes and a target site mutation as a possible mechanism for resistance. Whole-plant bioassays also suggested that the resistance problem is more widespread in Chhattisgarh than in Kerala. This study confirmed the first case of evolved resistance in barnyardgrass to bispyribac-sodium in rice fields of India. Nomenclature: Bispyribac-sodium; barnyardgrass; Echinochloa crus-galli (L.) P. Beauv.; rice; Oryza sativa L.","PeriodicalId":23710,"journal":{"name":"Weed Technology","volume":"37 1","pages":"236 - 242"},"PeriodicalIF":1.4,"publicationDate":"2023-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46548226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Weed TechnologyPub Date : 2023-04-01DOI: 10.1017/wet.2023.22
Emily Duenk, N. Soltani, Robert T. Miller, D. Hooker, D. Robinson, P. Sikkema
{"title":"Effect of glufosinate rate and addition of ammonium sulfate on annual weed control in glyphosate/glufosinate/2,4-D–resistant soybean","authors":"Emily Duenk, N. Soltani, Robert T. Miller, D. Hooker, D. Robinson, P. Sikkema","doi":"10.1017/wet.2023.22","DOIUrl":"https://doi.org/10.1017/wet.2023.22","url":null,"abstract":"Abstract The development of glufosinate-resistant soybean cultivars has created opportunities for use of glufosinate applied postemergence for weed control. Four field experiments were conducted in 2021 and 2022 to ascertain the effect of glufosinate rate and the addition of ammonium sulfate on annual weed control in glyphosate/glufosinate/2,4-D–resistant soybean. An increased glufosinate rate of 500 from 300 g ai ha–1 improved control of common ragweed, common lambsquarters, redroot pigweed, and foxtail species and resulted in decreased density and dry biomass of common lambsquarters and foxtail species. The addition of ammonium sulfate to glufosinate increased control of common lambsquarters, 2 and 8 wk after application (WAA), and of foxtail species, 2, 4, and 8 WAA, but did not improve control of common ragweed and redroot pigweed. Increasing the dose of glufosinate from 300 to 500 g ai ha–1 improves control of common ragweed, redroot pigweed, common lambsquarters, and foxtail species; however, the benefit of the addition of ammonium sulfate to glufosinate is weed species-specific. Nomenclature: Glyphosate; glufosinate; common ragweed; Ambrosia artemisiifolia L.; common lambsquarters; Chenopodium album L.; green foxtail; Seteria viridis (L.) P. Beauv.; velvetleaf; Abutilon theophrasti Medik.; soybean; Glycine max (L.) Merr.","PeriodicalId":23710,"journal":{"name":"Weed Technology","volume":"37 1","pages":"141 - 146"},"PeriodicalIF":1.4,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49143839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Weed TechnologyPub Date : 2023-04-01DOI: 10.1017/wet.2023.25
Amar S. Godar, J. Norsworthy, T. Barber
{"title":"Enlist™ corn tolerance to preemergence and postemergence applications of synthetic auxin and ACCase-inhibiting herbicides","authors":"Amar S. Godar, J. Norsworthy, T. Barber","doi":"10.1017/wet.2023.25","DOIUrl":"https://doi.org/10.1017/wet.2023.25","url":null,"abstract":"Abstract Allowing the use of two additional modes of action (MOAs), Enlist™ corn is a novelty in the continuum of herbicide-resistant crop development efforts that have occurred since the 1990s. Knowledge of Enlist corn tolerance to labeled herbicides and other herbicides within the same MOA for various use and/or exposure scenarios is not well established. Four site-year field experiments for preemergence (PRE) and postemergence (POST) applications were conducted at sites in Fayetteville (2021 and 2022) and Tillar (2020 and 2021), Arkansas, to evaluate Enlist corn response following PRE or POST applications of synthetic auxin herbicides or those that inhibit acetyl-CoA carboxylase (ACCase). A non-Enlist and an Enlist corn hybrid were used for each herbicide treatment to establish differential tolerance. Injury response to PRE application varied among site-years; clethodim was the only herbicide that occasionally caused significant (7% to 17%) injury to Enlist corn. None of the PRE treatments affected plant height, stand, or yield of Enlist corn; these responses were generally similar or better for Enlist corn compared to non-Enlist corn. Enlist corn showed significant injury to POST applications of florpyrauxifen-benzyl (>10%), fluazifop-P-butyl and quizalofop-P-ethyl (>5%), and clethodim and sethoxydim (>75%) 1 wk after application (WAA). These initial injury responses to clethodim and sethoxydim were generally reflected in Enlist corn yield; however, the minimal injury from fluazifop-P-butyl and quizalofop-P-ethyl did not affect yield. Injury to non-Enlist corn with POST-applied ACCase-inhibiting herbicides 2 WAA was >80%, resulting in a proportionate yield reduction. Even though florpyrauxifen-benzyl caused more initial injury to non-Enlist corn, yield reduction in non-Enlist corn was occasionally less than of Enlist corn, with both hybrids experiencing >75% yield reduction. In summary, Enlist corn may occasionally show transient injury even to labeled herbicides when applied POST, and even though the injury from florpyrauxifen-benzyl is initially mild, it nonetheless results in substantial yield loss. Nomenclature: florpyrauxifen-benzyl; fluazifop-P-butyl; quizalofop-P-ethyl; corn, Zea mays L.","PeriodicalId":23710,"journal":{"name":"Weed Technology","volume":"37 1","pages":"147 - 155"},"PeriodicalIF":1.4,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49379225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Weed TechnologyPub Date : 2023-04-01DOI: 10.1017/wet.2023.19
Katelyn A. Venner, E. Ervin, S. Koo, J. Peppers, S. Askew
{"title":"Effect of core cultivation, fertility, and plant growth regulators on recovery of voided creeping bentgrass greens canopies following annual bluegrass control via methiozolin","authors":"Katelyn A. Venner, E. Ervin, S. Koo, J. Peppers, S. Askew","doi":"10.1017/wet.2023.19","DOIUrl":"https://doi.org/10.1017/wet.2023.19","url":null,"abstract":"Abstract Methiozolin is commonly used for the safe and selective removal of annual bluegrass from creeping bentgrass golf greens. Studies were conducted in 2013 and 2014 with the objective of assessing fertility programs consisting of synthetic fertilizers and biostimulants, with and without the plant growth regulator trinexapac-ethyl, to aid putting green canopy recovery following annual bluegrass removal via methiozolin. Additional studies were conducted to compare recovery of creeping bentgrass following an aggressive core aerification event with fertility programs with and without methiozolin. In all cases, the addition of 7 kg ha–1 of N-P-K from fertilizer or biostimulant biweekly to greens increased turfgrass recovery time by 1 to 3 wk compared to a standard green's fertility program alone. Creeping bentgrass treated with biostimulants recovered equivalent to or quicker than creeping bentgrass treated with synthetic fertilizer (SF) in all cases. In the presence of methiozolin treatments, trinexapac-ethyl reduced time to 90% recovery (T90) by 0.25 to 0.5 wk at two locations, and increased T90 recovery time by 0.1 wk at one location. Otherwise, plots treated with SF plus trinexapac-ethyl were equivalent to plots treated with SF only. Methiozolin slowed turfgrass recovery time at one location where severe drought stress occurred but not at the other location that did not experience drought stress. These results suggest that turf managers should increase fertilizer treatments but will not need to discontinue trinexapac-ethyl use to maximize creeping bentgrass recovery following annual bluegrass control with methiozolin. These data also suggest that methiozolin has the potential to negatively affect creeping bentgrass recovery when drought stress is experienced. Nomenclature: Methiozolin; trinexapac-ethyl; annual bluegrass; Poa annua L. POAAN; creeping bentgrass; Agrostis stolonifera L. AGSST","PeriodicalId":23710,"journal":{"name":"Weed Technology","volume":"37 1","pages":"185 - 191"},"PeriodicalIF":1.4,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44545300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Weed TechnologyPub Date : 2023-04-01DOI: 10.1017/wet.2023.34
Tao Li, Huawei Qian, Guohui Yuan, Jiequn Fan, Shuiliang Guo
{"title":"Germination ecology and response to herbicides of Ludwigia prostrata and their implication for weed control in paddy fields","authors":"Tao Li, Huawei Qian, Guohui Yuan, Jiequn Fan, Shuiliang Guo","doi":"10.1017/wet.2023.34","DOIUrl":"https://doi.org/10.1017/wet.2023.34","url":null,"abstract":"Abstract Prostrate water primrose is a troublesome weed in rice paddy fields. A study was conducted to determine the influence of environmental and agronomic factors on its emergence. The efficacy of herbicides on this species was also examined. The germination percentage of mature seeds remained above 90% within 180 d after harvest, indicating a low primary dormancy of this species. Light stimulated seed germination. Seeds buried deeper than 0.5 cm did not form seedlings. These results suggest that stale seedbed practices and deep tillage operations can mitigate the occurrence of this species in paddy fields. The optimum temperature for germination varied from 25/15 C to 35/25 C. The osmotic potential and salt concentration needed to inhibit 50% of maximum germination were –0.4 MPa and 197 mM, respectively. Seeds were tolerant to flooding and did not germinate at pH 8 to 10. The preemergence herbicides oxadiazon, oxadiargyl, and butachlor had excellent control efficacy on prostrate water primrose, with a 95.4% to 100% reduction in seedling number and a 99.2% to 100% reduction in biomass, respectively. The postemergence herbicides MCPA-Na + bentazone, bentazone, MCPA-Na, and fluroxypyr applied at the 2- to 3-leaf stage of prostrate water primrose provided a 90.6% to 100% reduction in seedling number and a 99.3% to 100% reduction in biomass. The results of this study can help in developing sustainable and effective integrated weed management strategies for controlling prostrate water primrose in paddy fields. Nomenclature: Bentazon; butachlor; fluroxypyr; MCPA-Na; oxadiargyl; oxadiazon; prostrate water primrose; Ludwigia prostrata Roxb","PeriodicalId":23710,"journal":{"name":"Weed Technology","volume":"37 1","pages":"197 - 204"},"PeriodicalIF":1.4,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49376926","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}