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This final project research was conducted at the Kuala Pesilam Balai Gajah estate, Division I, PT. Bahruny, North Sumatra Province. This study took place from July to July 2021. This study aims to determine the pattern of weed control in the circle on production as well as rainfall and rainy days. This study uses a descriptive method by collecting secondary data from the garden: rainfall and production data. The results of this study can indicate that Indonesia's unstable palm oil production is caused by several factors, namely genetic factors, biotic factors (weeds) and abiotic factors (rainfall and rainy days). Production in 2020 is the highest production of oil palm for 4 years (2017-2020) with a total production of 5,971,760 Kilograms with an area of 336.96 hectares. The amount of rainfall is 2371 mm and rainy days is 117 days with weed control patterns on the disk carried out 4 times a year. Production in 2018 was the lowest production of oil palm for 4 years (2016-2020) with a total production of 4,032,338 kg, with an area of 267.96 Ha. The amount of rainfall is 1854 mm and rainy days is 112 rainy days with weed control patterns on the disc 2 times a year. The optimal rainfall for the growth and production of oil palm plants is 2,000 mm, but with 1846 mm of rainfall it does not mean it is not good for the growth and production of oil palm plants as long as there is no water deficit, so this rainfall is still included in the criteria for growing oil palm. Production in 2018 was the lowest production of oil palm for 4 years (2016-2020) with a total production of 4,032,338 kg, with an area of 267.96 Ha. The amount of rainfall is 1854 mm and rainy days is 112 rainy days with weed control patterns on the disc 2 times a year. The optimal rainfall for the growth and production of oil palm plants is 2,000 mm, but with 1846 mm of rainfall it does not mean it is not good for the growth and production of oil palm plants as long as there is no water deficit, so this rainfall is still included in the criteria for growing oil palm. Production in 2018 was the lowest production of oil palm for 4 years (2016-2020) with a total production of 4,032,338 kg, with an area of 267.96 Ha. The amount of rainfall is 1854 mm and rainy days is 112 rainy days with weed control patterns on the disc 2 times a year. The optimal rainfall for the growth and production of oil palm plants is 2,000 mm, but with 1846 mm of rainfall it does not mean it is not good for the growth and production of oil palm plants as long as there is no water deficit, so this rainfall is still included in the criteria for growing oil palm.

Ascochyta blight epidemics have been observed in many countries since the early 1900s but studies on an interaction between the amount of inoculum, environmental factors and the spatiotemporal development of Ascochyta blight are rare due to the historic emphasis on developing resistant cultivars and chemical control of the disease. I used generalised linear mixed models to investigate key environmental factors affecting the spatiotemporal development of Ascochyta blight from primary infection foci. Briefly, four replicate plots (20 m × 20 m) of a susceptible chickpea cultivar were planted at two different locations (Billa Billa and Tosari) in Queensland, Australia. Four naturally infested stubble pieces were placed at the centre of each newly emerged chickpea plot 14 days after sowing. The number of infected plants was counted in 1 m2 observation quadrats at the distances of 3, 6 and 9 m in a concentric arrangement. The number of infected plants increased with each assessment date, approaching 100% plant infections at the time of final assessment. The rate of disease progress was significantly faster at Tosari. The rate of disease progress significantly decreased as the distance from the primary infection foci increased. There was a significant positive effect of an optimum temperature, increasing rainfall and omni-directional wind. The influence of wind speed was not significant. The finding that single infection foci were enough to spread disease across whole plots indicate that limited inoculum is not a barrier in the development of an epiphytotic under conducive conditions.

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Aims: This study aimed to evaluate the control of Eleusine indica Gaertn. and Digitaria insularis (L.) Fedde through the combination of soil cover with green manure straw and herbicides applied in pre-emergence. Study Design: Each weed species was evaluated in different experiments. The experiments were set up in a greenhouse in a completely randomized design and arranged in a factorial scheme (5×4)+2, with four replications. Place and Duration of Study: Center of Agricultural Sciences, São Paulo, Brazil, from May 2019 to May 2020. Methodology: Seeds of Digitaria insularis and Eulesine indica were sown at a depth of 1 cm from the soil surface. Then, the pots were watered, and the straw of Cajanus cajan, Sorghum bicolor, Crotalaria juncea, Crotalaria spectabilis, and Crotalaria breviflora was deposited on the surface. The pre-emergence herbicides trifluralin (900 g ai ha−1), pendimethalin (1200 g ai ha−1), clomazone (1000 g ai ha−1), and s-metolachlor (1920 g ai ha−1) were applied one day after the weed seeds were sown. The percentage of weed control was evaluated at 10, 20, and 30 days after emergence (DAE). The plant shoot was cut at 30 DAE and the weight of dry biomass was determined. The control without herbicide and with soil cover crop and no herbicide and no soil cover were also evaluated. Results: Sorghum bicolor, Cajanus cajan, and Crotalaria breviflora were the most effective in controlling Eleusine indica when no herbicide was applied. Only Sorghum bicolor showed a satisfactory control of Digitaria insularis without the use of chemical management (above 80%). The association of pre-emergence herbicides with soil cover showed high control of weeds. Conclusion: The results showed that the association between chemical and cultural methods is an effective alternative to control Eulesine indica and Digitaria insularis.

Glyphosate application avoids some problems associated with manually controlling Carpobrotus. However, before it can be extended, we must understand whether residual glyphosate affects the restorat...

A flutuação populacional do percevejo-do-grão, Oebalus spp. (Hemiptera: Pentatomidae), em lavouras de arroz irrigado em Santa Catarina não é conhecida. Isto dificulta o planejamento e a adoção de estratégias para o manejo de pragas, como também a racionalização da aplicação de inseticidas para controle. Desta forma, objetivou-se monitorar a atividade de vôo de Oebalus spp. para conhecer a flutuação populacional e determinar as épocas de maior ocorrência das espécies e morfologias nas lavouras. Armadilhas luminosas foram instaladas em áreas de cultivo de arroz irrigado na Estação Experimental da Epagri em Itajaí, SC e no Centro de Treinamento da Epagri em Araranguá, SC. A partir de setembro de 2008 a abril de 2020, as armadilhas foram ligadas das 16:00 às 9:00h, uma vez por semana, exceto de maio a agosto de cada ano, quando permaneceram desligadas. A flutuação populacional do percevejo-do-grão em arroz irrigado caracteriza-se por dois momentos de maior incidência de indivíduos, em novembro/dezembro e em fevereiro, correspondendo aos períodos de ocorrência de percevejos hibernados e dos enxames de verão, respectivamente. A espécie Oebalus poecilus (Dallas) prevalece sobre Oebalus ypsilongriseus (DeGeer) e as populações com morfologias hibernal ou estival ocorrem alternadamente ao longo do ano, se sobrepondo apenas a partir de meados de fevereiro.

The control of rodent pests with novel rodenticides is an important strategy subsequently they are cost-effective in reduction of agriculture damage in the urban environment. The current field stud...

Fountain grass (Pennisetum alopecuroides) is a common ornamental grass because of its glossy foliage and showy inflorescence. However, there have been reports of populations growing outside of cultivation and demonstrating invasive tendencies. There is limited research of the chemical control of fountain grass in natural areas. The objective of this experiment was to evaluate the impact of glyphosate, sethoxydim, and fluazifop on fountain grass. Treatments consisted of 2250 and 4500 g⋅ha–1 glyphosate, 262.5 and 525 g⋅ha–1 sethoxydim, and 200 and 400 g⋅ha–1 fluazifop; a nontreated control group was also included. The percent herbicide injury was determined visually 1, 3, 4, 6, and 10 weeks after treatment (WAT). Both rates of glyphosate resulted in 100% of the foliage injured by 3 WAT. The application of flauzifop and sethoxydim led to intermediate results ranging from 15% to 23% injury by 6 WAT, with no significant difference between active ingredients or rates. Nontreated control plants exhibited little to no injury throughout the study. Flauzifop, sethoxydim, and glyphosate all caused visible injury to fountain grass. For complete, fast-acting control, glyphosate is recommended. Herbicide control coupled with restorative plantings of native plants can help reduce invasive plant pressure and improve biodiversity of natural areas.

In South African forest plantations, white grubs (Scarabaeidae larvae) can contribute to high transplant mortality following re-establishment. Currently registered insecticides are considered highl...

Little is known about best herbicidal weed option for weed eradication in soybean in agro-climatic circumstances of Sargodha, Punjab, Pakistan. A two year field study was accomplished at College of Agriculture experimental site Sargodha in spring seasons of 2018 and 2019 to evaluate the efficacy of different herbicides adjacent to major weeds present in soybean. The study consisted of 8 herbicide treatments including two pre-emergence herbicides (pendimethalin at 489.1 g a.i. ha-1, pendimethalin + S-metolachlor at 731.1 g a.i. ha-1) which are applied immediately after sowing and six post-emergence herbicides (oxyfluorfen at 237.1 g a.i. ha-1, metribuzin at 518.7 g a.i. ha-1, quizalofop-p-ethyl at 148.2 g a.i. ha-1, acetochlor at 741 g a.i. ha-1, halosulfuron at 37 g a.i. ha-1and topramezone at 21.5 g a.iha-1) which were used 25 days subsequent to sowing. In contrast to control, all herbicides have shown significant decline in weed density (up to 94%) and dry weight (up to 88%); and caused significant increases in plant height (up to 85%), pod bearing branches (up to 77%), number of pods per plant (up to 83%), 100-seed weight (up to 37%) and seed yield (up to 160%) of soybean. Among herbicides, topramezone at 21.5 g a.i ha-1 gave significantly the highest (1234 and 1272 kg ha-1 in the year 2018 and 2019) seed yield of soybean and HEIs (1.28 and 1.03 in year 2018 and 2019, respectively). However, oxyfluorfen at 237.1 g a.i. ha-1, pendimethalin + S-metolachlor at 731.1 g a.i. ha-1, pendimethalin at 489.1 g a.i. ha-1, quizalofop-p-ethyl at 148.2 g a.i.ha-1 followed it. The regression analysis depicted a significant negative moderate relationship of soybean seed yield with weed dry weight (R2 = 0.7074), and pods per plant (R2 = 0.7012) was proved to be the main yield component responsible for higher yield of soybean.

Made available in DSpace on 2020-12-12T02:48:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Digitaria insularis (sourgrass) is a monocotyledon weed of difficult control and high invasive behavior. Atrazine is widely applied in the Americas to control weeds in maize culture, but its efficiency against D. insularis is limited. The incorporation of atrazine into poly(epsilon-caprolactone) nanocapsules increased the herbicidal activity against susceptible weeds; however, the potential of this nanoformulation to control atrazine-tolerant weeds including D. insularis has not yet been tested. Here, we evaluated the post-emergent herbicidal activity of nanoatrazine against D. insularis plants during initial developmental stages. The study was carried out in a greenhouse, using pots filled with clay soil. Plants with two or four expanded leaves were treated with conventional or nanoencapsulated atrazine at 50 or 100% of the recommended dosage (1,000 or 2,000 g ∙ ha−1), followed by the evaluation of physiological, growth, and control parameters of the plants. Compared with conventional herbicide, both dosages of nanoatrazine induced greater and faster inhibition of D. insularis photosystem II activity at both developmental stages. Atrazine nanoencapsulation also improved the control of D. insularis plants, especially in the stage with two expanded leaves. In addition, nanoatrazine led to higher decreases of dry weight of four-leaved plants than atrazine. The use of the half-dosage of nanoatrazine was equally or more efficient in affecting most of the evaluated parameters than the conventional formulation at full dosage. Overall, these results suggest that the nanoencapsulation of atrazine potentiated its post-emergent herbicidal activity against D. insularis plants at initial developmental stages, favoring the control of this atrazine-tolerant weed. Agronomy Department Londrina State University Department of Environmental Engineering São Paulo State University (UNESP) Department of Animal and Plant Biology Londrina State University Department of Environmental Engineering São Paulo State University (UNESP) CNPq: 306583/2017-8

As a control measure against weeds, the use of herbicides is an effective and inexpensive alternative. However, there are no products recommended for the cultivation of cowpea in Brazil, making it necessary to search for alternative solutions. The objective of this study was to evaluate the effect of herbicides applied in the pre- and post-emergence on cowpea nodulation and production under conditions of the Amazonian savannah. Two experiments were carried out in a randomized block design with four replicates, using the cowpea cultivar BRS Aracê subjected to the pre-emergence herbicides: Metribuzin, Sulfentrazone, S-metolachlor, Pendimethalin, Oxadiazon, Alachlor, Metribuzin + Pendimethalin, Metribuzin + Alachlor and Quizalofop-p-ethyl, Bentazon, Fomesafen, Imazethapyr, Imazamox + Bentazon, Quizalofop-p-ethyl + Imazethapyr, Quizalofop-p-ethyl + Ima-zamox and Quizalofop-p-ethyl + Bentazon, and post-emergence herbicides: Quizalofop-p-ethyl, Bentazon, Fomesafen, Imazetha-pyr, Imazamox + Bentazon, Quizalofop-p-ethyl + Imazethapyr, Quizalofop-p-ethyl + Imazamox, and Quizalofop-p-ethyl + Bentazon. The number of nodules in each plant, the dry matter of nodules, dry matter of roots and the grain yield were evaluated. According to the results obtained, the management of weeds in pre- or post-emergence according to the herbicide used affects the nodulation and productivity of cowpea under the conditions of the Amazonian savannah. The herbicides Metribuzin in pre-emergence, and Fomesafen and the mixture of Quizalofop-p-ethyl + Imazethapyr in post-emergence are not recommended for weed control in cowpea. The application of Oxadiazon, Alachlor, and Pendimethalin in pre-emergence can be considered interesting because they do not inhibit the development of the root system or the nodulation of cowpea which provides a greater grain yield. Regarding weed control strategies at post-emergence, the application of the herbicide Imazethapyr and the combination of the herbicides quizalofop-p-ethyl + imazamox, Quizalofop-p-ethyl + Bentazon and Imazamox + Bentazon allow satisfactory levels of grain yield, root system development and nodulation of cowpea. RESUMEN Como medida de control contra las malezas, el uso de herbicidas es una alternativa efectiva y asequible. Sin embargo, no hay productos recomendados para el cultivo de frijol caupí en Brasil, por lo que es necesario buscar soluciones alternativas. El objetivo de este estudio fue evaluar el efecto de herbicidas aplicados en pre- y post-emergencia sobre la nodulación y productividad del frijol caupí bajo las condiciones de la sabana amazónica. Se realizaron dos experimentos en bloques al azar con cuatro repeticiones, utilizando el cultivar de frijol caupí BRS Aracê sometido a los herbicidas pre-emergentes: Metribuzina, Sulfentrazona, S-metolaclor, Pendimetalina, Oxadiazón, Alaclor, Metribuzina + Pendimetalina, Metribuzina + Alaclor y Quizalofop-p-etil, Bentazona, Fomesafen, Imazetapir, Imazamox + Bentazona, Quizalofop-p-etil + Imazetapir, Quizalofop-p-etil + Imazamox y Quizalofop-p-etil + Bentazona, y herbicidas post-emergentes: Quizalofop-p-etil, Bentazona, Fomesafen, Imazetapir, Imazamox + Bentazona, Quizalofop-p-etil + Imazetapir, Quizalofop-p-etil + Imazamox, Quizalofop-p-etil + Bentazona. Se evaluaron el número de nódulos por planta, la masa seca de nódulos, la masa seca de raíces y el rendimiento de grano. Según los resultados obtenidos en este estudio, el manejo de malezas en pre o post-emer-gencia de acuerdo con el herbicida utilizado afecta la nodulación y el rendimiento de grano de frijol caupí bajo condiciones de la sabana amazónica. Los herbicidas Metribuzina en pre-emergen-cia, y Fomesafen y la mezcla de Quizalofop-p-etil + Imazetapir en post-emergencia no se recomiendan para el control de malezas en frijol caupí. La aplicación de Oxadiazón, Alaclor y Pendimetalina en la pre-emergencia puede considerarse interesante porque no inhiben el desarrollo del sistema radicular o la nodulación de frijol caupí lo que proporciona un mayor rendimiento de grano. En lo relacionado con las estrategias de control de malezas posteriores a la emergencia, la aplicación del herbicida Imazetapir y la combinación de los herbicidas Quizalofop-p-etil + Imazamox, Quizalofop-p-etil + Bentazona e Imazamox + Bentazona permiten niveles satisfactorios de rendimiento de grano, desarrollo del sistema de raíces y nodulación de frijol caupí.

A field experiment was conducted at Regional Agricultural Research Station, Bangladesh Agricultural Research Institute (BARI), Ishwardi, Pabna during 2013-14 to find out an effective integrated management package for controlling root knot nematode, Meloidogyne incognita of pointed gourd. The following treatments were T1 = Spore suspension of T. harzanium added to around the roots of seedling, T2 = Dry neem leaves @100 g seedling-1, T3 = Furadan 5G @ 40 kg ha-1, T4 = Poultry litter @ 5 t ha-1, T5 = Mustard oil cake @ 800 kg ha-1, T6 = Furadan 5G + Dry neem leaves, T7 = Furadan 5G + Poultry litter, T8 = Furadan 5G + Mustard oil cake and T9 = Control were tested for their performance against the disease. Gall index ranged from 3.33-7.67. Significantly lower gall index (3.33) was recorded in treatment T7= Furadan 5G + Poultry litter and maximum gall index (7.67) was recorded in treatment T9= Control plot. The highest yield (24.97 t ha-1) was recorded in Furadan 5G + Poultry litter treated plot where are the lowest yield (7.53 t ha-1) was in Control plot. The incorporation of Poultry litter with Furadan 5G increased the efficiency of the treatment and gave satisfactory result to reduce root knot disease and to improve plant growth and yield of pointed gourd. Int. J. Agril. Res. Innov. Tech. 9(2): 51-56, December 2019

The effects of different measures within maize cropping technology, aimed to suppress weeds as a part of integrated weed management (IWM) system, are analysed and evaluated in this manuscript, in line with the results of longterm experiments. For sustainable maize (Zea mays L.) production, implementation of IWM system aiming to reduce reliance on chemical weed control within Europe is a key priority. This IWM system includes all possible solutions, such as preventive, direct, biological, mechanical and alternative measures. A cropping system approach is essential to manage weeds, utilize genetic potential of maize genotypes and reduce yield losses due to weed competition. Long-term experiments are nowadays rare, but they are an excellent and reliable method for comparing cropping systems regarding yield and reduction of weed infestation level. In the research program implemented at the Maize Research Institute Zemun Polje in Central Serbia, the effects of different cropping measures and their interactions as a part of IWMs were studied during ten years. Maize rotations with winter wheat (Triticum aestivum L.) and soybean (Glycine max (L.) Merr.), combined with herbicide application, showed the best effect on weed biomass reduction, 92.1% and 92.2%, respectively. Winter wheat was a better preceding crop for maize than soybean, especially in combination with herbicides applied in recommended as well as in half of recommended rate. Intensification of soil tillage significantly reduced maize weed infestation, especially abundance of perennial species: Johnson grass (Sorghum halepense (L.) Pers.), Canada thistle (Cirsium arvense (L.) Scop.) and field bindweed (Convolvulus arvensis L.). Other measures, such as type of fertilizer, maize row space and crop density, cover cropping and intercropping also affected weed biomass production in maize fields. Maize growing with reduced row spacing contributed to weed biomass reduction by 27.4%, while application of slow-release urea contributed to crop competitiveness. Weed biomass in sweet maize (Zea mays L. convar. saccharata) grown with common vetch as a cover crop was significantly reduced (48.5 g m-2) compared with the treatment without a cover crop (564.3 g m-2). Straipsnyje analizuojama kukurūzų įvairių auginimo priemonių ir auginimo technologijų įtaka piktžolių mažėjimui ilgalaikio eksperimento metu. Europoje tvaraus kukurūzų auginimo svarbiausias prioritetas yra integruota piktžolių kontrolės (IPK) sistema, kuria siekiama sumažinti priklausomumą nuo cheminės piktžolių kontrolės. IPK sistema apima visus įmanomus sprendimus, pavyzdžiui, prevencines tiesiogines, biologines, mechanines ir alternatyvias priemones. Augalininkystės sistemų metodas yra labai svarbus siekiant kontroliuoti piktžoles, išnaudoti kukurūzų genotipų genetinį potencialą ir sumažinti derliaus nuostolius dėl piktžolių. Šiais laikais ilgalaikiai eksperimentai vykdomi retai, tačiau jie yra puikus ir patikimas būdas augalininkystės sistemas palyginti pagal derlių ir pasėlių piktžolėtumo mažinimą. Centrinėje Serbijoje esančiame Kukurūzų tyrimų institute Zemun Polje įgyvendinant mokslinių tyrimų programą, kelerius metus kaip IPK dalis buvo tirta įvairių agrotechnikos priemonių įtaka ir jų sąveika. Siekiant sumažinti piktžolių biomasę efektyviausia buvo paprastųjų kukurūzų (Zea mays L.) sėjomaina su žieminiais kviečiais ir sojomis kartu su herbicidų panaudojimu – atitinkamai 92,1 ir 92,2 %. Žieminiai kviečiai buvo geresnis kukurūzų priešsėlis nei sojos, ypač kartu su herbicidais, panaudojus ir rekomenduojamą normą, ir pusę rekomenduojamos jų normos. Žemės dirbimas turėjo reikšmingos įtakos kukurūzų pasėlio piktžolėtumui, ypač daugiametėms piktžolėms: Sorghum halepense (L.) Pers., Cirsium arvense (L.) Scop. ir Convolvulus arvensis L. Kitos priemonės, pavyzdžiui, trąšų rūšis, kukurūzų tarpueilių plotis ir augalų tankumas, antsėlis bei įsėlis, taip pat turėjo įtakos piktžolių biomasei kukurūzų lauke. Kukurūzų auginimas mažesniu tarpueilių pločiu piktžolių biomasę sumažino 27,4 %, o lėtai atpalaiduojamo karbamido panaudojimas padidino augalų konkurencinę gebą. Saldžiųjų kukurūzų (Zea mays L. convar. saccharata), augintų su vikių antsėliu, pasėlyje piktžolių biomasė reikšmingai sumažėjo (48,5 g m-2), palyginus su variantu be antsėlio (564,3 g m-2).

Potential yield of sorghum [Sorghum biocolor (L.) Moench] in the semi-arid agro-ecologies of East Africa is curtailed by several biotic, abiotic and socio-economic constraints. Striga is one of the major biotic constraints that causes up to 90% yield losses in sorghum in the region. In these regions Striga hermonthica and S. asiatica, are widely distributed, and severely affecting sorghum production and productivity. Several Striga management strategies are available that can be integrated to synergistically combat the weed. The use of resistant sorghum genotypes that are compatible with Fusarium oxysporum f.sp. strigae (FOS), a biocontrol agent of Striga, together with host plant resistance could promote integrated Striga management (ISM). This strategy is yet to be explored in most SSA countries where sorghum serves as a staple food crop for millions of households. This review discusses the management options available to control S. hermonthica and S. asiatica in sorghum. Breeding sorghum for Striga resistance and compatibility to FOS are highlighted as key components of integrated Striga management.

Seeds are a fundamental and essential part of the persistent growth in agriculture production, as 90% of crops are produced from seeds that require constant treatment to prevent seed-borne and seasonal diseases and damage from insects. Seed treatment is a method of applying some definite agents to the seed before sowing to make seeds resistant to pathogens, insects, and other pests. Seed priming is an advanced seed treatment technique that is used to avoid the consequences of traditional treatment procedures. In priming, seeds are subjected to effective solutions depending on the characteristics of the seeds, which improves performance under controlled environments and in field conditions. Seed biopriming is a single, attractive, and cost-effective approach to induce disease resistance and increase germination. In a broader sense, it is a biological strategy and an effective alternative to chemical control that is unique in that it uses live beneficial microbes.

Rattail fescue (Vulpia myuros (L.) C.C. Gmel.) is a self-pollinating winter annual grassy weed of winter annual crops. The problems with V. myuros are mostly associated with no-till cropping systems where glyphosate application before sowing or emergence of the crop is the most important control measure. Ineffective V. myuros control has been reported following glyphosate applications. Experiments were performed to study the effectiveness of glyphosate on V. myuros, and determine the causes of the lower performance of glyphosate on V. myuros compared to other grass weeds. Estimated GR50 values demonstrated that V. myuros was less susceptible to glyphosate than Apera spica-venti regardless of the growth stage. Within each species, glyphosate efficacy at different growth stages was closely related to spray retention. However, the low susceptibility to glyphosate in V. myuros was not caused by lower retention as previously suggested. A significantly lower shikimic acid accumulation in V. myuros compared to A. spica-venti was associated with a higher activity of the EPSPS enzyme in V. myuros. Nevertheless, the relative responses in EPSPS activity to different glyphosate concentrations were similar in the two grass species, which indicate that EPSPS from V. myuros is as susceptible to glyphosate as EPSPS from A. spica-venti suggesting no alternation in the binding site of EPSPS. The results from the current study indicate that V. myuros is less susceptible to glyphosate compared to A. spica-venti, and the low susceptibility of V. myuros is caused by an increased EPSPS enzyme activity.

Fraise mowing is a maintenance practice that may serve as a non-chemical means of controlling the problematic weed annual bluegrass (Poa annua L.) in bermudagrass (Cynodon spp.) given reports of efficacy on other turfgrass species. However, an understanding of practitioner decision-making in implementing fraise mowing as a weed-control measure remains unknown. A field study was conducted in Knoxville, TN and repeated in space in Jay, FL during summer 2019 to assess bermudagrass regrowth and subsequent annual bluegrass control, following fraise mowing at depths of 1.5 and 3.0 cm compared to a non-treated check (0 cm). Bermudagrass recovered more quickly at the 1.5 cm depth than the 3.0 cm depth and was the swiftest in Florida. Fraise mowing at either depth resulted in a 41–97% reduction in annual bluegrass populations. A qualitative study was conducted in spring 2021, which engaged eight turfgrass managers from Tennessee and Florida via individual interviews in order to understand barriers and challenges to fraise mowing application. Turfgrass managers had positive views of fraise mowing but described challenges in implementation for weed control including cost, labor, area closure, and debris removal.

Made available in DSpace on 2022-05-01T09:31:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-07-01 Droplet size is one of the most important factors that affect spray deposition and weed control through the use of herbicides. The aim of this study was to evaluate the influence of the droplet size on the spray deposition and control of Euphorbia heterophylla and Urochloa ruziziensis by using glyphosate. The treatments included spraying glyphosate with fine, medium, coarse, very coarse, and ultra-coarse droplet sizes to determine the deposition, uniformity of distribution, visual control, and dry weight reduction (DWR). The treatments were compared with the values of the dose required to achieve 50% DWR or 50% visual control (C50) at 7, 14, 21, and 28 days after herbicide application. Fine and medium droplet sizes afforded high deposition values and low distribution uniformities in E. heterophylla. Fine and medium droplet sizes yielded the lowest C50 on visual control and DWR in E. heterophylla, respectively. The droplet size did not affect the spray deposition on U. ruziziensis plants; however, the larger droplets had less uniformity of distribution. In U. ruziziensis plants, spraying glyphosate with coarse and medium droplet sizes yielded the lowest values of C50 to visual control and DWR, respectively. Universidade Estadual Paulista “Júlio de Mesquita Filho” Faculdade de Engenharia Universidade Estadual Paulista “Júlio de Mesquita Filho” Faculdade de Ciências Agrárias e Tecnológicas Universidade Estadual Paulista “Júlio de Mesquita Filho” Faculdade de Ciências Agronômicas Universidade Estadual Paulista “Júlio de Mesquita Filho” Faculdade de Engenharia Universidade Estadual Paulista “Júlio de Mesquita Filho” Faculdade de Ciências Agrárias e Tecnológicas Universidade Estadual Paulista “Júlio de Mesquita Filho” Faculdade de Ciências Agronômicas

Due to natural tolerance to most widely used herbicides for grass weed control, prosulfocarb as pre-emergence or early post-emergence herbicide and mesosulfuron + iodosulfuron as post-emergence herbicide are the mainstays of any chemical control program for Vulpia myuros in Denmark. However, farmers often report variable efficacy of these herbicides on V. myuros compared to other grass weeds. Dose–response experiments were conducted to evaluate the performance of prosulfocarb and mesosulfuron + iodosulfuron on V. myuros. Prosulfocarb was sprayed at different plant growth stages to study the influence of plant growth stage on the performance of prosulfocarb on V. myuros in comparison with the more susceptible grass weed species Apera spica-venti. Doses causing 50% reduction in response variable (ED50) were estimated from the dose–response analysis. The ED50 values revealed a higher tolerance of V. myuros to prosulfocarb and mesosulfuron + iodosulfuron than A. spica-venti. The relative difference in the effectiveness of prosulfocarb between V. myuros and A. spica-venti was constant among plant growth stages studied. The highest levels of V. myuros control were achieved when prosulfocarb was sprayed pre-emergence (BBCH 00), while the control substantially declined at later growth stages. The results from the current study document the tolerance of V. myuros to prosulfocarb and mesosulfuron + iodosulfuron and highlight the importance of optimization of prosulfocarb spray timing for achieving maximum control of V. myuros.

The adoption of chemical fallow rotations in Pacific Northwest dryland winter wheat production has caused a weed species composition shift in which scouringrush has established in production fields. Thus, there has been interest in identifying herbicides that effectively control scouringrush in winter wheat–chemical fallow cropping systems. Field experiments were established in growers’ fields near Reardan, WA, in 2014, and The Dalles, OR, in 2015. Ten herbicide treatments were applied to mowed and nonmowed plots during chemical fallow rotations. Scouringrush stem densities were quantified the following spring and after wheat harvest at both locations. Chlorsulfuron plus MCPA-ester resulted in nearly 100% control of scouringrush through wheat harvest. Before herbicide application, mowing had no effect on herbicide efficacy. We conclude chlorsulfuron plus MCPA-ester is a commercially acceptable treatment for smooth and intermediate scouringrush control in winter wheat–chemical fallow cropping systems; however, the lack of a positive yield response when scouringrushes were controlled should factor into management decisions.

Trifluralin, a pre-emergent herbicide, is widely used in Brazil in the weed grass management in restoration areas. The objective was to evaluate the tolerance of Piptadenia gonoacantha to t...

Direct-seeded rice alternative to transplanted rice system is less labor intensive, easier to plant, and consume less water. The advantages of direct-seeded rice have been proved by many research workers, but yet it is not very much adapted by farmers. Weeds reduce cost effectiveness of direct-seeded rice. A study was conducted to evaluate the effect of different row spacing and weed management practices on the performance of aerobic rice at Agronomic Research Area, University of Agriculture, Faisalabad, during summer season of 2013. Fine rice variety ‘Super Basmati’ was used for experiment in a randomized complete block design with factorial arrangements with three replications. Hand drill sowing with row spacing comprised 15 cm, 22.5 cm, and 30 cm was practiced. Weed scouting hoeing (hand pulling is weed free treatment for comparison with the others and hoeing is a type of mechanical weeding) and pre-emergence herbicide, followed by post-emergence herbicide, were the weed management practices. Weeds data and rice yield parameters were measured. Maximum reduction in weed density (86%) and weed dry weight (79%) was recorded for pre-emergence, followed by for post-emergence herbicide in crop sown at 15 cm row spacing.

Whole-plant response experiments in pots and field experiments over two years were conducted to study the resistance levels and chemical control options of sterile oat (Avena sterilis L.) in typica...

Glyphosate-resistant (GR) weeds are the biggest concern for all cotton stakeholders worldwide. Currently, 43 weeds species are resistant to glyphosate and the number is increasing at an alarming rate. Soil residual/pre-emergence (PRE) herbicides like Pendimethalin and S-metolachlor can be effectively used for the control of GR weeds; however, their use is very limited at farmer’s side due to the adoption of herbicide-tolerant technology with complete reliance on glyphosate. The present study was conducted to evaluate the performance of PRE and post-emergence (POST) herbicides in glyphosate-tolerant (GT) cotton. The herbicide treatments were pendimethalin and S-metolachlor as PRE-residual, and glyphosate was applied as POST at 20 days after sowing (DAS) either alone or in combination with other herbicides like S-metolachlor, pendimethalin, and haloxyfop. A second application of glyphosate was made at 35 DAS. Results revealed that pendimethalin and S-metolachlor treatments gave 100% suppression of all dominant weeds and increased lint yield by 310–350% as compared to weedy control. In contrast, glyphosate applied once and twice, gave weed biomass reduction of only 10–86%, and increased lint yield by 136–185% over weedy control. This research established that PRE application of pendimethalin and S-metolachlor can be included in the weed management program of GT cotton.

The efficacy of five fungicide seed treatments as a management tool against blackleg on spring canola was evaluated under greenhouse and field conditions in North Dakota. Blackleg, caused by Leptosphaeria maculans, inflicts the greatest yield losses when infecting seedlings before they reach the six-leaf growth stage. In greenhouse studies, 10-day-old seedlings were inoculated with L. maculans spore suspensions and evaluated 12 days later and at maturity or inoculated 12, 20, or 28 days after planting and evaluated at maturity. In field trials conducted in 2017 and 2018, severity was assessed at maturity. In the greenhouse, all fungicide seed treatments reduced (P = 0.05) disease severity at the seedling stage, but only the protection provided by Obvius (fluxapyroxad + pyraclostrobin + metalaxyl) and Helix Vibrance (mefenoxam + fludioxonil + sedaxane + difenoconazole + thiamethoxam) reduced (P < 0.05) severity at the adult stage; however, none of them provide effective protection when plants were inoculated 20 days after planting or later. In field trials, none of the treatments significantly (P > 0.05) improved plant stand and yield or reduced disease incidence and severity. Although fungicide seed treatment is a valuable tool, it should not be used as the only method to manage blackleg disease.