WorldWideScience

Sample records for weed control

  1. Site Specific Weed Control Technologies

    DEFF Research Database (Denmark)

    Christensen, Svend; Søgaard, Henning Tangen; Kudsk, Per;

    2009-01-01

    describe the basic parts of site specific weed control technologies, comprising of weed sensing systems, weed management models and precision weed control implements. A review of state-of-the-art technologies shows that several weed sensing systems and precision implements have been developed over the last...... of knowledge about the economic and environmental potential for increasing the resolution of weed control. The integration of site-specific information on weed distribution, weed species composition and density, and the effect on crop yield, is decisive for successful site-specific weed management.   Keywords......Site-specific weed control technologies are defined as machinery or equipment embedded with technologies that detect weeds growing in a crop and, taking into account predefined factors such as economics, takes action to maximise the chances of successfully controlling them. In the article, we...

  2. Controlling Landscape Weeds.

    Science.gov (United States)

    Nuss, James Robert, Jr.

    This agriculture extension service publication from Pennsylvania State University discusses the control of common grass and broadleaf weeds through the use of mulches and herbicides. The section on mulches discusses the different types of mulching materials, their advantages and disadvantages, herbicide-mulch combinations, and lists source of…

  3. Controlling Landscape Weeds.

    Science.gov (United States)

    Nuss, James Robert, Jr.

    This agriculture extension service publication from Pennsylvania State University discusses the control of common grass and broadleaf weeds through the use of mulches and herbicides. The section on mulches discusses the different types of mulching materials, their advantages and disadvantages, herbicide-mulch combinations, and lists source of…

  4. INTEGRATED WEED CONTROL IN MAIZE.

    Science.gov (United States)

    Latré, J; Dewitte, K; Derycke, V; De Roo, B; Haesaert, G

    2015-01-01

    Integrated pest management has been implemented as a general practice by EU legislation. As weed control actually is the most important crop protection measure in maize for Western Europe, the new legislation will have its impact. The question is of course which systems can be successfully implemented in practice with respect to labour efficiency and economical parameters. During 3 successive growing seasons (2007, 2008, 2009) weed control in maize was evaluated, the main focus was put on different techniques of integrated weed control and was compared with chemical weed control. Additionally, during 4 successive growing seasons (2011, 2012, 2013 and 2014) two objects based on integrated weed control and two objects based on mechanical weed control were compared to about twenty different objects of conventional chemical weed control. One of the objects based on mechanical weed control consisted of treatment with the flex-tine harrow before and after emergence in combination with chemical weed control at a reduced rate in 3-4 leave stage. The second one consisted of broadcast mechanical treatments before and after emergence followed by a final in-row application of herbicides and an inter-row cultivation at 6-7(8) leave stage. All trials were conducted on the Experimental farm of Bottelare HoGent-UGent on a sandy loam soil. Maize was growing in 1/3 crop rotation. The effect on weed growth as well as the economic impact of the different applications was evaluated. Combining chemical and mechanical weed control is a possible option in conventional farming but the disadvantages must be taken into account. A better planned weed control based on the real present weed-population in combination with a carefully thought-out choice of herbicides should also be considered as an IPM--approach.

  5. Weed Identification and Control in Vegetable Crops.

    Science.gov (United States)

    Ferretti, Peter A., Comp.

    This agriculture extension service publication from Pennsylvania State University examines weed control and identification in vegetable crops. Contents include: (1) Types of weeds; (2) Reducing losses caused by weeds, general control methods and home garden weed control; (3) How herbicides are used; (4) Specific weeds in vegetable plantings; and…

  6. Weed Identification and Control in Vegetable Crops.

    Science.gov (United States)

    Ferretti, Peter A., Comp.

    This agriculture extension service publication from Pennsylvania State University examines weed control and identification in vegetable crops. Contents include: (1) Types of weeds; (2) Reducing losses caused by weeds, general control methods and home garden weed control; (3) How herbicides are used; (4) Specific weeds in vegetable plantings; and…

  7. [Alfalfa Planting as weed control

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a letter to farming cooperators regarding the stipulations surrounding alfalfa plantings in lieu of small grain plantings to provide weed control,...

  8. Biotechnology in weed control

    Science.gov (United States)

    Biotechnology can be used to enhance the management of weeds in several ways. Crops have been made resistant to herbicides by inserting transgenes that impart herbicide resistance into the plant genome. Glyphosate and glufosinate-resistant crops are commercialized in North America and crops made res...

  9. Site-specific weed control technologies

    DEFF Research Database (Denmark)

    Christensen, S; Søgaard, H T; Kudsk, P

    2009-01-01

    Site-specific weed control technologies are defined as machinery or equipment embedded with technologies that detect weeds growing in a crop and, taking into account predefined factors such as economics, takes action to maximise the chances of successfully controlling them. In the article, we...... describe the basic parts of site specific weed control technologies, comprising of weed sensing systems, weed management models and precision weed control implements. A review of state-of-the-art technologies shows that several weed sensing systems and precision implements have been developed over the last...... two decades, though barriers prevent their breakthrough. Most important among these is the lack of a truly robust weed recognition method, owing to mutual shading among plants and limitations in the capacity of highly accurate spraying and weeding apparatuses.   Another barrier is the lack...

  10. A STUDY ON WEED CONTROL IN SOYBEAN

    Directory of Open Access Journals (Sweden)

    S. TJITROSEMITO

    1991-01-01

    Full Text Available Two field experiments on weed control in soybeans were carried out at BIOTROP, Bogor, Indonesia from February to June, 1989. The critical period for weed control was found to be between 20 - 40 days after planting of soybean (c. v. Wilis grown at a planting distance of 40 x 10 cm. It did not coincide with the fastest growth in terms of trifoliate leaf number. Further studies were suggested to understand the physiological growth of soybean related to weed control. Pendimethalin at 660- 1320 g a.e./ha applied one day after sowing did not cause any phytotoxic effect to soybean and had good weed control performance.

  11. The future for weed control and technology.

    Science.gov (United States)

    Shaner, Dale L; Beckie, Hugh J

    2014-09-01

    This review is both a retrospective (what have we missed?) and prospective (where are we going?) examination of weed control and technology, particularly as it applies to herbicide-resistant weed management (RWM). Major obstacles to RWM are discussed, including lack of diversity in weed management, unwillingness of many weed researchers to conduct real integrated weed management research or growers to accept recommendations, influence or role of agrichemical marketing and governmental policy and lack of multidisciplinary research. We then look ahead to new technologies that are needed for future weed control in general and RWM in particular, in areas such as non-chemical and chemical weed management, novel herbicides, site-specific weed management, drones for monitoring large areas, wider application of 'omics' and simulation model development. Finally, we discuss implementation strategies for integrated weed management to achieve RWM, development of RWM for developing countries, a new classification of herbicides based on mode of metabolism to facilitate greater stewardship and greater global exchange of information to focus efforts on areas that maximize progress in weed control and RWM. There is little doubt that new or emerging technologies will provide novel tools for RMW in the future, but will they arrive in time? © 2013 Her Majesty the Queen in Right of Canada Pest Management Science © 2013 Society of Chemical Industry.

  12. Critical Period of Weed Control in Aerobic Rice

    OpenAIRE

    Anwar, M. P.; A. S. Juraimi; Samedani, B.; Puteh, A.; Man, A.

    2012-01-01

    Critical period of weed control is the foundation of integrated weed management and, hence, can be considered the first step to design weed control strategy. To determine critical period of weed control of aerobic rice, field trials were conducted during 2010/2011 at Universiti Putra Malaysia. A quantitative series of treatments comprising two components, (a) increasing duration of weed interference and (b) increasing length of weed-free period, were imposed. Critical period was determined th...

  13. Soil solarization for weed control in carrot

    Directory of Open Access Journals (Sweden)

    MARENCO RICARDO ANTONIO

    2000-01-01

    Full Text Available Soil solarization is a technique used for weed and plant disease control in regions with high levels of solar radiation. The effect of solarization (0, 3, 6, and 9 weeks upon weed populations, carrot (Daucus carota L. cv. Brasília yield and nematode infestation in carrot roots was studied in São Luís (2º35' S; 44º10' W, MA, Brazil, using transparent polyethylene films (100 and 150 mm of thickness. The maximum temperature at 5 cm of depth was about 10ºC warmer in solarized soil than in control plots. In the study 20 weed types were recorded. Solarization reduced weed biomass and density in about 50% of weed species, including Cyperus spp., Chamaecrista nictans var. paraguariensis (Chod & Hassl. Irwin & Barneby, Marsypianthes chamaedrys (Vahl O. Kuntze, Mitracarpus sp., Mollugo verticillata L., Sebastiania corniculata M. Arg., and Spigelia anthelmia L. Approximately 40% of species in the weed flora were not affected by soil mulching. Furthermore, seed germination of Commelina benghalensis L. was increased by soil solarization. Marketable yield of carrots was greater in solarized soil than in the unsolarized one. It was concluded that solarization for nine weeks increases carrot yield and is effective for controlling more than half of the weed species recorded. Mulching was not effective for controlling root-knot nematodes in carrot.

  14. Effect of stale seedbed preparations and subsequent weed control in lettuce (cv. Iceboll) on weed densities

    NARCIS (Netherlands)

    Riemens, M.M.; Weide, van der R.Y.; Bleeker, P.O.; Lotz, L.A.P.

    2007-01-01

    The effects of stale seedbed preparations and several weed control methods on the emergence of weeds in lettuce were studied. The specific goal was to evaluate the use of a stale seedbed in combination with chemical or mechanical weed control methods in the field. Depending on location and year,

  15. Effect of stale seedbed preparations and subsequent weed control in lettuce (cv. Iceboll) on weed densities

    NARCIS (Netherlands)

    Riemens, M.M.; Weide, van der R.Y.; Bleeker, P.O.; Lotz, L.A.P.

    2007-01-01

    The effects of stale seedbed preparations and several weed control methods on the emergence of weeds in lettuce were studied. The specific goal was to evaluate the use of a stale seedbed in combination with chemical or mechanical weed control methods in the field. Depending on location and year, sta

  16. A Review on Reasons of Increasing Perennial Weeds and Control Technology of Perennial Weeds in Heilongjiang Province

    Institute of Scientific and Technical Information of China (English)

    ZHAO Changshan; HE Fuli; SHI Na; YAN Chunxiu

    2009-01-01

    The main reasons that perennial weeds has becoming the dominant weeds in Heilongjiang Province were summarized.The biological mechanism that explained why it was difficult to control perennial weeds was analyzed. During dormancy course,variation regularity of some inner matters in perennial weeds was researched and new tentative for controlling the perennial weeds was pointed out.

  17. Critical period of weed control In cumin (Cuminum cyminum)

    OpenAIRE

    azade hoseyni; alireza koochaki; mehdi nassiri mahalati

    2009-01-01

    In order to evaluate the critical period of weed control in Cumin, an experiment with Complete Randomized Block Design and three replications was conducted in experimental field of Faculty of Agriculture, Ferdowsi University of Mashhad, During 2004-2005 growing season. Treatments included different combinations of weed free and weed infested periods (20, 30, 40 and 80 days after germination) plus weedy check and weed free check. Critical period weed control was evaluated with Gompertz and Log...

  18. Integration of herbicides with manual weeding for controlling the weeds in rice under saline environment.

    Science.gov (United States)

    Hakim, M A; Juraimi, Abdul Shukor; Hanafi, M M; Rafii, Mohd Y; Ismail, Mohd Razi; Karim, S M Rezaul; Kausar, H

    2015-11-01

    The pot experiment was conducted to select appropriate integrated weed management method in rice under different salinity levels (0, 4 and 8 dS m(-1)). All the parameters including rice and weed measured were significantly influenced by weed control treatments at all salinity levels. Treatments including weed-free condition, Pretilachlor @0.375 kg ai ha(-1) + hand weeding, Propanil + Thiobencarb @ 0.9 kg ai ha(-1) and 1.8 kg ai ha(-1)+ hand weeding performed better under all salinity levels. Pretilachlor @ 0.375 kg ai ha(-1) with one round of hand weeding and propanil + thiobencarb 0.9 kg ai ha(-1) + 1.8 kg ai ha(-1) with one round of hand weeding were comparable to weed-free yields, and were superior to other treatments under salinity condition. Considering all the parameters, pretilachlor @ 0.375 kg ai ha(-1) + one round of hand weeding (at 65 DAT), propanil + thiobencarb 0.9 kg ai ha(-1) +1.8 kg ai ha(-1) + one round of hand weeding (at 65 DAT) gave the most effective control of weeds in rice under saline environments.

  19. The effect of sowing strategy, row distance and mechanical weed control on weeds and yield in organic winter wheat

    OpenAIRE

    Rasmussen, Ilse A.

    2002-01-01

    A series of field experiments were carried out in winter wheat grown under organic conditions in Denmark on fields with different weed pressure. The treatments were sowing strategy (normal sowing time, late sowing and false seedbed), row distance (12 cm and 24 cm row distance) and weed control method (untreated, mechanical weed control (weed harrowing at 12 cm supplemented with row hoeing at 24 cm), and herbicide weed control). Weed biomass was largest at the normal sowing time and was reduce...

  20. Effects of Planting Date, Time and Methods of Weed Control on Weed Density and Biomass in Cumin Fields

    Directory of Open Access Journals (Sweden)

    R. Ghorbani

    2011-01-01

    Full Text Available Abstract Two field experiments were carried out in order to evaluate the effect of planting date, method and date of weed control on weed density and biomass in the experimental research field, Faculty of Agriculture, Ferdowsi University of Mashhad, during 2006 and 2007. Treatments included planting date (30 December, 20 January and 30 February, weeding date (first true leaf, start of branching and beginning of flowering stages and weed control methods (hand weeding, fire treatment and control. The results showed that there were significant differences in the number of weeds between different sowing dates, weeding dates and control methods. The highest mean density and biomass of weeds were obtained on the planting date, 30 February, and when weed was controlled at the first leaf appearance stage with fire treatment. The most appropriate time for weed control was at the beginning of cumin flowering. Fire treatment reduced weed growth in the first half of growing season. However, hand weeding significantly reduced weed density and biomass in the second half of cumin growing season. The first planting date caused the lowest mean weed biomass and the highest cumin yield compared to later planting dates. Hand weeding treatment contained lower mean weed density and biomass compared to fire treatment, however, cumin yield was lower in hand weeding plots than fire treatment. Keywords: Cultural control, Cuminum cyminum, Fire, Hand weeding, Control time

  1. Effectiveness of the Primextra Gold in controlling weeds of ...

    African Journals Online (AJOL)

    Effectiveness of the Primextra Gold in controlling weeds of Cucumber ( Cucumis Sativus L. ) ... Journal of Applied Sciences and Environmental Management ... The efficacy of Primextra Gold herbicide in controlling weeds in cucumber was ...

  2. Developments in physical weed control in Northwest Europe

    Directory of Open Access Journals (Sweden)

    Riemens, Marieen

    2016-02-01

    Full Text Available In North West Europe there is an increasing need for advanced weed control methods. This paper gives an overview of the developments in physical weed control methods. Current innovations in interrow weeding focus on systems that take over the steering function of the driver in order to make them more precise and reduce crop losses. The latest developments in intrarow weeding techniques involve technologies that automatically detect and classify crop and weed plants and use this information to guide a weeding device. Several commercially available examples are presented.

  3. WEED SURVEYING OF PHACELIA (PHACELIA TANACETIFOLIA L.) AND EVALUATING THE EFFICIENCY OF THE WEED CONTROL.

    Science.gov (United States)

    Horváth, E; Szabó, R

    2014-01-01

    The experiment was set up in an area of 9 ha that was split into 4 plots: in plot 1 the row spacing was 12 cm and the seeding rate was 10 kg; in plot 2 the row spacing was 24 cm and the seeding rate was 10 kg; in plot 3 the row spacing was 24 cm and the seeding rate was 8 kg; in plot 4 the row spacing was 12 cm and the seeding rate was 8 kg. After the weed surveying, the total weed coverage was established as follows: in plot 1 the total weed coverage was 11.34%, in plot 2 it was 12.3%, in plot 3 it was 18%, and in plot 4 the total weed coverage was 15%. Based on the weed survey, on the test area the following dicotyledon weeds belonging to the T4 Raunkiaer plant life-form category occupied the highest percentage: heal-all, black-bindweed, goosefoot. The proportion of the perennial dicotyledons: field bindweed (G3), tuberous pea (G1), white campion (H3) was negligible. In all four cases the weed control was executed using the same herbicide in the same doses and with regard to the weed species it showed the same level of efficiency. The smaller row spacing and higher seeding rate has a beneficial effect on the weed suppressing capacity of the crop, the crop's weed suppressing capacity is better and the development of the weeds becomes worse.

  4. Weed Control in Black Walnut Plantations

    Science.gov (United States)

    Calvin F. Bey; Robert D. Williams

    1976-01-01

    Weeds must be controlled for at least 3 years to successfully establish walnut plantations. Whether by cultivating or applying chemicals, a strip or spot 4 feet wide is sufficient the first 2 years, followed by a 6-foot spot or strip for the third and fourth years.

  5. Weed Control Trials in Cottonwood Plantations

    Science.gov (United States)

    R. M. Krinard

    1964-01-01

    Weed control in the first year is essential for establishing a cottonwood plantation, for the young trees can neither survive nor grow well if they must compete with other plants. Once the light and moisture conditions are established in its favor, cottonwood becomes the fastest growing tree in the South.

  6. Acetic acid and weed control in onions

    Science.gov (United States)

    Weed control is a major challenge in conventional and organic production systems, especially for organically produced sweet onion (Allium cepa L.). Although corn gluten meal shows great promise as an organic preemergent herbicide for onions, research has shown the need for supplemental, postemergen...

  7. BIOLOGICAL CONTROL OF WEEDS BY MEANS OF PLANT PATHOGENS

    Directory of Open Access Journals (Sweden)

    Marija Ravlić

    2014-06-01

    Full Text Available Biological control is the use of live beneficial organisms and products of their metabolism in the pests control. Plant pathogens can be used for weed control in three different ways: as classical, conservation and augmentative (inoculative and inundated biological control. Inundated biological control involves the use of bioherbicides (mycoherbicides or artificial breeding of pathogens and application in specific stages of crops and weeds. Biological control of weeds can be used where chemical herbicides are not allowed, if resistant weed species are present or in the integrated pest management against weeds with reduced herbicides doses and other non-chemical measures, but it has certain limitations and disadvantages.

  8. Developments in physical weed control in Northwest Europe

    NARCIS (Netherlands)

    Riemens, M.M.

    2016-01-01

    In North West Europe there is an increasing need for advanced weed control methods. This paper gives an overview of the developments in physical weed control methods. Current innovations in interrow weeding focus on systems that take over the steering function of the driver in order to make them mor

  9. Pest Control in Corn and Soybeans: Weeds - Insects - Diseases.

    Science.gov (United States)

    Doersch, R. E.; And Others

    This document gives the characteristics and application rates for herbicides used to control annual weeds in corn, annual and perennial broadleaf weeds in corn, quackgrass and yellow nutsedge in corn, and annual weeds in soybeans. It also gives insecticide use information for corn and soybeans. A brief discussion of disease control in corn and…

  10. Biological weed control with soil fungi? Antagonistic effects of arbuscular mycorrhizal fungi on the growth of weeds

    NARCIS (Netherlands)

    Veiga, R.

    2012-01-01

    Excessive weed growth represents one of the major threats to crop production especially when reliance on herbicides is reduced. Biological weed control is an alternative, environmentally-sound method that, combined with other weed control practices, can contribute to an effective weed management in

  11. A century of progress in weed control in hardwood seedbeds

    Science.gov (United States)

    David B. South

    2009-01-01

    Weeds have existed in nurseries since before the time Bartram grew hardwoods during the 18th century. Hand weeding was the primary method of weed control during the first part of the 20th century. From 1931 to 1970, advances in chemistry increased the use of herbicides, and advances in engineering increased the reliance on machines for cultivation. Many managers now...

  12. Weed control through seedling abrasion with an organic fertilizer

    Science.gov (United States)

    Many tools exist to control weeds in organic crops, and each has utility in specific situations. Nevertheless, surveys of organic farmers indicate that weed management often is second only to labor supply as their main bottleneck for success. Consequently, new tactics for managing weeds are desirabl...

  13. Critical period of weed control In cumin (Cuminum cyminum

    Directory of Open Access Journals (Sweden)

    azade hoseyni

    2009-06-01

    Full Text Available In order to evaluate the critical period of weed control in Cumin, an experiment with Complete Randomized Block Design and three replications was conducted in experimental field of Faculty of Agriculture, Ferdowsi University of Mashhad, During 2004-2005 growing season. Treatments included different combinations of weed free and weed infested periods (20, 30, 40 and 80 days after germination plus weedy check and weed free check. Critical period weed control was evaluated with Gompertz and Logestic functions. Traits measured were yield and yield components, harvest index of cumin and also number and weight of weed species. Results showed the critical period was between 24-38 days after germination. With increasing interfereing period at early or late growth stages of cumin, the economic yield was reduced. By extending weeding periods at early stage of growth or during the growth period, dry weight of weeds were reduced, while extending weeding period at the end of growth stage and also weed free during growth period, early or late stages of growth had no significant effects on yield components except on number of umbels per plant. Harvest index was positively affected by early weeding. It appears that early weeding was somehow more effective on yield components for cumin.

  14. Applicator Training Manual for: Aquatic Weed Control.

    Science.gov (United States)

    Herron, James W.

    The aquatic weeds discussed in this manual include algae, floating weeds, emersed weeds, and submerged weeds. Specific requirements for pesticide application are given for static water, limited flow, and moving water situations. Secondary effects of improper application rates and faulty application are described. Finally, techniques of limited…

  15. Applicator Training Manual for: Aquatic Weed Control.

    Science.gov (United States)

    Herron, James W.

    The aquatic weeds discussed in this manual include algae, floating weeds, emersed weeds, and submerged weeds. Specific requirements for pesticide application are given for static water, limited flow, and moving water situations. Secondary effects of improper application rates and faulty application are described. Finally, techniques of limited…

  16. Chemical and mechanical weed control in soybean (Glycine max

    Directory of Open Access Journals (Sweden)

    Weber, Jonas Felix

    2016-02-01

    Full Text Available In this study we investigated the possibility of chemical and mechanical weed control strategies in soybean. Soybean field experiments were carried out in 2013 and 2014 in Southern Germany. Five treatments including common herbicide mixtures and four mechanical weed control treatments, implementing a harrow and a hoe, were tested at different locations. In the herbicide experiments two treatments were applied by PRE emergence herbicides (metribuzin, clomazone, dimethenamid and metribuzin, flufenacet, clomazone and another two treatments were sprayed with a combination of PRE + POST emergence herbicides (metribuzin, flufenacet, thifensulfuron and pendimethalin, thifensulfuron, bentazone, cycloxydim. Furthermore, a POST herbicide treatment was implemented (thifensulfuron, bentazone, thifensulfuron and fluazifop-P-butyl. In the mechanical weed control experiments, treatments were: three times hoeing, PRE emergence harrowing plus three times hoeing, hoeing and harrowing in rotation or three times harrowing. In both experiments an untreated control was included. A 90% weed control efficacy and 23% yield increase was observed in the POST herbicide treatment. PRE + POST treatments resulted in 92% to 99% weed control efficiency and 15% yield increase compared to the untreated control. In the mechanical weed control experiments the combination of PRE emergence harrowing and POST emergence hoeing resulted in 82% weed control efficiency and 34% higher yield compared to the untreated control. Less weed control efficiency (72% was observed in the harrow treatment, leading to 20% higher yield compared to the control. The suitability of both strategies for implementation in “Integrated Weed Management” has been investigated.

  17. A non-chemical system for online weed control.

    Science.gov (United States)

    Rueda-Ayala, Victor; Peteinatos, Gerassimos; Gerhards, Roland; Andújar, Dionisio

    2015-03-30

    Non-chemical weed control methods need to be directed towards a site-specific weeding approach, in order to be able to compete the conventional herbicide equivalents. A system for online weed control was developed. It automatically adjusts the tine angle of a harrow and creates different levels of intensity: from gentle to aggressive. Two experimental plots in a maize field were harrowed with two consecutive passes. The plots presented from low to high weed infestation levels. Discriminant capabilities of an ultrasonic sensor were used to determine the crop and weed variability of the field. A controlling unit used ultrasonic readings to adjust the tine angle, producing an appropriate harrowing intensity. Thus, areas with high crop and weed densities were more aggressively harrowed, while areas with lower densities were cultivated with a gentler treatment; areas with very low densities or without weeds were not treated. Although the weed development was relatively advanced and the soil surface was hard, the weed control achieved by the system reached an average of 51% (20%-91%), without causing significant crop damage as a result of harrowing. This system is proposed as a relatively low cost, online, and real-time automatic harrow that improves the weed control efficacy, reduces energy consumption, and avoids the usage of herbicide.

  18. The definition of electro impulses used in weed control

    Directory of Open Access Journals (Sweden)

    Judaev I.V.

    2008-01-01

    Full Text Available In modern agriculture the use of chemicals and machines in weed control is not environmental and soil friendly. The use of electro impulses is offered to traditional ways of weed control. The researches done on technical characteristics of such operation and influence of these results on ecology gave picture that the use of electro impulses in weed control is harmless for environment and that is very effective. The basis for the technical project at designing of the electro impulse installation used with standard wheel tractor obtained data about values of electric energy doses that can make damage in various kinds of weeds.

  19. Ecological Intensification Through Pesticide Reduction: Weed Control, Weed Biodiversity and Sustainability in Arable Farming

    Science.gov (United States)

    Petit, Sandrine; Munier-Jolain, Nicolas; Bretagnolle, Vincent; Bockstaller, Christian; Gaba, Sabrina; Cordeau, Stéphane; Lechenet, Martin; Mézière, Delphine; Colbach, Nathalie

    2015-11-01

    Amongst the biodiversity components of agriculture, weeds are an interesting model for exploring management options relying on the principle of ecological intensification in arable farming. Weeds can cause severe crop yield losses, contribute to farmland functional biodiversity and are strongly associated with the generic issue of pesticide use. In this paper, we address the impacts of herbicide reduction following a causal framework starting with herbicide reduction and triggering changes in (i) the management options required to control weeds, (ii) the weed communities and functions they provide and (iii) the overall performance and sustainability of the implemented land management options. The three components of this framework were analysed in a multidisciplinary project that was conducted on 55 experimental and farmer's fields that included conventional, integrated and organic cropping systems. Our results indicate that the reduction of herbicide use is not antagonistic with crop production, provided that alternative practices are put into place. Herbicide reduction and associated land management modified the composition of in-field weed communities and thus the functions of weeds related to biodiversity and production. Through a long-term simulation of weed communities based on alternative (?) cropping systems, some specific management pathways were identified that delivered high biodiversity gains and limited the negative impacts of weeds on crop production. Finally, the multi-criteria assessment of the environmental, economic and societal sustainability of the 55 systems suggests that integrated weed management systems fared better than their conventional and organic counterparts. These outcomes suggest that sustainable management could possibly be achieved through changes in weed management, along a pathway starting with herbicide reduction.

  20. Restoring interventions: eco-sustainable weed control

    Directory of Open Access Journals (Sweden)

    Facciotto G

    2006-01-01

    Full Text Available The creation and enlargement of ecological networks is paramount to conserve plant biodiversity, to offer refuge to the local fauna and to improve the environment in general. Such networks intend to conserve areas of great natural value, to restore degraded areas and to link them physically through the creation of ecological corridors. The work described was carried out in order to improve and enlarge an ecological corridor within the experimental farm “Mezzi” of CRA-ISP at Casale Monferrato (AL - Italy. One of its bigger problems, weed control, was solved by increasing the planting density, by sowing herbaceous crops and mulching with woody chips.

  1. Controlling weeds with fungi, bacteria and viruses: a review

    OpenAIRE

    Harding, Dylan P.; Raizada, Manish N

    2015-01-01

    Weeds are a nuisance in a variety of land uses. The increasing prevalence of both herbicide resistant weeds and bans on cosmetic pesticide use has created a strong impetus to develop novel strategies for controlling weeds. The application of bacteria, fungi and viruses to achieving this goal has received increasingly great attention over the last three decades. Proposed benefits to this strategy include reduced environmental impact, increased target specificity, reduced development costs comp...

  2. Critical period of weed control in aerobic rice.

    Science.gov (United States)

    Anwar, M P; Juraimi, A S; Samedani, B; Puteh, A; Man, A

    2012-01-01

    Critical period of weed control is the foundation of integrated weed management and, hence, can be considered the first step to design weed control strategy. To determine critical period of weed control of aerobic rice, field trials were conducted during 2010/2011 at Universiti Putra Malaysia. A quantitative series of treatments comprising two components, (a) increasing duration of weed interference and (b) increasing length of weed-free period, were imposed. Critical period was determined through Logistic and Gompertz equations. Critical period varied between seasons; in main season, it started earlier and lasted longer, as compared to off-season. The onset of the critical period was found relatively stable between seasons, while the end was more variable. Critical period was determined as 7-49 days after seeding in off-season and 7-53 days in main season to achieve 95% of weed-free yield, and 23-40 days in off-season and 21-43 days in main season to achieve 90% of weed-free yield. Since 5% yield loss level is not practical from economic view point, a 10% yield loss may be considered excellent from economic view point. Therefore, aerobic rice should be kept weed-free during 21-43 days for better yield and higher economic return.

  3. Critical Period of Weed Control in Aerobic Rice

    Directory of Open Access Journals (Sweden)

    M. P. Anwar

    2012-01-01

    Full Text Available Critical period of weed control is the foundation of integrated weed management and, hence, can be considered the first step to design weed control strategy. To determine critical period of weed control of aerobic rice, field trials were conducted during 2010/2011 at Universiti Putra Malaysia. A quantitative series of treatments comprising two components, (a increasing duration of weed interference and (b increasing length of weed-free period, were imposed. Critical period was determined through Logistic and Gompertz equations. Critical period varied between seasons; in main season, it started earlier and lasted longer, as compared to off-season. The onset of the critical period was found relatively stable between seasons, while the end was more variable. Critical period was determined as 7–49 days after seeding in off-season and 7–53 days in main season to achieve 95% of weed-free yield, and 23–40 days in off-season and 21–43 days in main season to achieve 90% of weed-free yield. Since 5% yield loss level is not practical from economic view point, a 10% yield loss may be considered excellent from economic view point. Therefore, aerobic rice should be kept weed-free during 21–43 days for better yield and higher economic return.

  4. Post-directed weed control in bell peppers

    Science.gov (United States)

    Organic pepper (Capsicum annuum L.) producers need appropriate herbicides that can effectively provide post-emergent weed control. Research was conducted in southeast Oklahoma (Atoka County, Lane, OK) to determine the impact of a potential organic herbicide on weed control efficacy, crop injury, an...

  5. Aquatic weed control within an integrated water management framework.

    NARCIS (Netherlands)

    Querner, E.P.

    1993-01-01

    Aquatic weed control, carried out by the water boards in the Netherlands, is required to maintain sufficient discharge capacity of the surface water system. Weed control affects the conditions of both surface water and groundwater. The physically based model MOGROW was developed to simulate the flow

  6. How to Identify and Control Water Weeds and Algae.

    Science.gov (United States)

    Applied Biochemists, Inc., Mequon, WI.

    Included in this guide to water management are general descriptions of algae, toxic algae, weed problems in lakes, ponds, and canals, and general discussions of mechanical, biological and chemical control methods. In addition, pictures, descriptions, and recommended control methods are given for algae, 6 types of floating weeds, 18 types of…

  7. Prevention and control of weeds, pests and diseases

    NARCIS (Netherlands)

    Sukkel, W.; Hommes, M.

    2009-01-01

    Weed control still requires major investments of money and labour in organic arable farming and field vegetable cultivation. For this reason, current research is focused to a large extent on the development of weed control strategies. These incorporate prevention as well as mechanical methods, and c

  8. How to Identify and Control Water Weeds and Algae.

    Science.gov (United States)

    Applied Biochemists, Inc., Mequon, WI.

    Included in this guide to water management are general descriptions of algae, toxic algae, weed problems in lakes, ponds, and canals, and general discussions of mechanical, biological and chemical control methods. In addition, pictures, descriptions, and recommended control methods are given for algae, 6 types of floating weeds, 18 types of…

  9. Determining treatment frequency for controlling weeds on traffic islands using chemical and non-chemical weed control

    DEFF Research Database (Denmark)

    Rask, Anne Merete; Larsen, S.U.; Andreasen, Christian

    2013-01-01

    Many public authorities rely on the use of non-chemical weed control methods, due to stringent restrictions on herbicide use in urban areas. However, these methods usually require more repeated treatments than chemical weed management, resulting in increased costs of weed management. In order...... to investigate the efficacy of four non-chemical weed control methods and glyphosate treatment, experiments were carried out on traffic islands in the growing seasons 2005 and 2006. Three trial sites were each divided into six treatment areas, which were either treated with glyphosate, flame, steam, hot air....../flame, hot water or left untreated. The treatments were carried out at regular, predetermined intervals throughout the growing season in 2004, whereas in 2005 and 2006 how many treatments that were required to keep weed cover below a predetermined acceptance level of 2% were investigated. Percentage weed...

  10. The Effect of Laser Treatment as a Weed Control Method

    DEFF Research Database (Denmark)

    Mathiassen, Solvejg K; Bak, Thomas; Christensen, Svend

    2006-01-01

    for weed control, however, require a systematic investigation of the relationship between energy density and the biological effect on different weed species, growth stages, etc. This paper investigates the effect of laser treatment directed towards the apical meristems of selected weed species...... chickweed), Tripleurospermum inodorum (scentless mayweed) and Brassica napus (oilseed rape). The experiment showed that laser treatment of the apical meristems caused significant growth reduction and in some cases had lethal effects on the weed species. The biological efficacy of the laser control method...... was related to wavelength, exposure time, spot size and laser power. The efficacy also varied between the weed species. The results indicate that the efficacy of laser treatments can be improved by a more precise pointing of the laser beam towards the apical meristems and optimisation of the energy density...

  11. Changes in weed infestation of common bean (Phaseolus vulgaris L. under conditions of strip intercropping and different weed control methods

    Directory of Open Access Journals (Sweden)

    Aleksandra Głowacka

    2012-12-01

    Full Text Available The experiment was conducted in the years 2004-2006 in a private farm in the village of Frankamionka in Zamość district. There were two experimental factors: I. Cultivation methods - sole cropping and strip intercropping; and II. Tending methods - mechanical, mechanical-chemical, and chemical weed control. The subject of the study was weed infestation of the Mela variety of common bean. Beans were sown between 30 April and 5 May. Weed infestation was assessed in the last week before harvesting by determining its floristic composition and the frequency of occurrence of particular weed species, as well as the air-dry weight of weeds. The dominant weed species were Galinsoga parviflora, Echinochloa crus-galli, Chenopodium album, and Amaranthus retroflexus, which comprised 84.7% of the total number of weeds. Strip intercropping markedly reduced the number of weeds per unit area (by 50%, as well as the dry weight of their aerial parts. The most effective method of weed control was the mechanical-chemical method, which resulted in the lowest occurrence of weeds. It also significantly reduced the weight of weeds.

  12. Determination of the critical period of weed control in corn using a thermal basis.

    OpenAIRE

    BEDMAR,FRANCISCO; Manetti,Pablo; MONTERUBBIANESI,GLORIA

    1999-01-01

    Field studies were conducted over 3 years in southeast Buenos Aires, Argentina, to determine the critical period of weed control in maize (Zea mays L.). The treatments consisted of two different periods of weed interference, a critical weed-free period, and a critical time of weed removal. The Gompertz and logistic equations were fitted to relative yields representing the critical weed-free and the critical time of weed removal, respectively. Accumulated thermal units were used to describe ea...

  13. Weed Control Sprayers: Calibration and Maintenance. Special Circular 81.

    Science.gov (United States)

    Myers, Arthur L.

    This manual covers aspects of calibration and maintenance of weed control sprayers including variables affecting application rate, the pre-calibration check, calculations, band spraying, nozzle tip selection, agitation, and cleaning. (BB)

  14. Weed Control Sprayers: Calibration and Maintenance. Special Circular 81.

    Science.gov (United States)

    Myers, Arthur L.

    This manual covers aspects of calibration and maintenance of weed control sprayers including variables affecting application rate, the pre-calibration check, calculations, band spraying, nozzle tip selection, agitation, and cleaning. (BB)

  15. Vinegar (20% acetic acid) broadcast application for broadleaf weed control in spring-transplanted onions

    Science.gov (United States)

    Organic weed control research was conducted in southeast Oklahoma to determine the effect of broadcast over-the-top applications of acetic acid (vinegar) on weed control efficacy, crop injury and onion yields. The experiment included 6 weed control treatments (2 application volumes, 2 hand-weeding ...

  16. Benefits of Precision Farming Technologies for Mechanical Weed Control in Soybean and Sugar Beet—Comparison of Precision Hoeing with Conventional Mechanical Weed Control

    Directory of Open Access Journals (Sweden)

    Christoph Kunz

    2015-04-01

    Full Text Available Weed infestations and associated yield losses require effective weed control measures in soybean and sugar beet. Besides chemical weed control, mechanical weeding plays an important role in integrated weed management systems. Field experiments were conducted at three locations for soybean in 2013 and 2014 and at four locations for sugar beet in 2014 to investigate if automatic steering technologies for inter-row weed hoeing using a camera or RTK-GNSS increase weed control efficacy, efficiency and crop yield. Treatments using precision farming technologies were compared with conventional weed control strategies. Weed densities in the experiments ranged from 15 to 154 plants m−2 with Chenopodium album, Polygonum convolvulus, Polygonum aviculare, Matricaria chamomilla and Lamium purpureum being the most abundant species. Weed hoeing using automatic steering technologies reduced weed densities in soybean by 89% and in sugar beet by 87% compared to 85% weed control efficacy in soybean and sugar beet with conventional weeding systems. Speed of weed hoeing could be increased from 4 km h−1 with conventional hoes to 7 and 10 km·h−1, when automatic steering systems were used. Precision hoeing technologies increased soybean yield by 23% and sugar beet yield by 37%. After conventional hoeing and harrowing, soybean yields were increased by 28% and sugar beet yield by 26%.

  17. Weed control and selectivity of flumioxazin in eucalyptus

    Directory of Open Access Journals (Sweden)

    Rafael Augusto Soares Tiburcio

    2012-12-01

    Full Text Available Flumioxazin is a registered herbicide for agricultural crops what is an important fact concerning integrated management for weeds in eucalyptus plantations. This study evaluated the efficiency of weed control and the phytotoxicity in eucalyptus plants caused by the herbicide flumioxazin applied alone or in tank mixture with sulfentrazone and isoxaflutole. The aim was to extend the use of thisherbicide in eucalyptus. The herbicide was applied to eucalyptus plants using precision backpack sprayer. It was evaluated, visually,the intoxication percentage and measured height and diameter of eucalyptus trees, the control plants and dry mass of weeds. It wasconcluded that flumioxazin is selective to the eucalyptus at the 125 g.ha-1 dosage, and its efficiency in controlling weeds pre-emergencewas better when mixed in the tank with isoxaflutole and sulfentrazone.

  18. Dynamics of weed populations : spatial pattern formation and implications for control

    NARCIS (Netherlands)

    Wallinga, J.

    1998-01-01

    Modelling studies were carried out to analyse spatio-temporal dynamics of annual weed populations and to identify the key factors that determine the long-term herbicide use of weed control programmes. Three different weed control programmes were studied.

    In the first weed

  19. Economics of supplemental weed control applications on spring-transplanted onions

    Science.gov (United States)

    Field research conducted to determine the relative benefits among alternative herbicides for weed control in onions (Allium cepa L.) measured weed control efficacy, impact of herbicides on crop injury, and the resulting weed competition on crop yields and marketable bulb size. Weed competition produ...

  20. Lawn Weeds and Their Control. North Central Regional Extension Publication No. 26.

    Science.gov (United States)

    Purdue Univ., Lafayette, IN. Cooperative Extension Service.

    This publication discusses lawn weed control for the twelve state north central region of the country. Written for use by homeowners, the publication focuses on weed identification and proper herbicide selection and application. Identification of weeds and safe and appropriate herbicide use are emphasized. Forty-six weed and turf plants are…

  1. Lawn Weeds and Their Control. North Central Regional Extension Publication No. 26.

    Science.gov (United States)

    Purdue Univ., Lafayette, IN. Cooperative Extension Service.

    This publication discusses lawn weed control for the twelve state north central region of the country. Written for use by homeowners, the publication focuses on weed identification and proper herbicide selection and application. Identification of weeds and safe and appropriate herbicide use are emphasized. Forty-six weed and turf plants are…

  2. Designing, modeling and controlling a novel autonomous laser weeding system

    DEFF Research Database (Denmark)

    Shahrak Nadimi, Esmaeil; Andersson, Kim Johan; Jørgensen, Rasmus Nyholm

    2009-01-01

    conveyor belts fully controlled by a Siemens PLC controller (programmable logic controller), a stereo vision system consisting of two cameras, a 2-axis laser beam deflection unit and a laser source. The main challenge in this project was to accurately estimate and reconstruct the weed growth center using...

  3. Controlling weeds with fungi, bacteria and viruses: a review.

    Science.gov (United States)

    Harding, Dylan P; Raizada, Manish N

    2015-01-01

    Weeds are a nuisance in a variety of land uses. The increasing prevalence of both herbicide resistant weeds and bans on cosmetic pesticide use has created a strong impetus to develop novel strategies for controlling weeds. The application of bacteria, fungi and viruses to achieving this goal has received increasingly great attention over the last three decades. Proposed benefits to this strategy include reduced environmental impact, increased target specificity, reduced development costs compared to conventional herbicides and the identification of novel herbicidal mechanisms. This review focuses on examples from North America. Among fungi, the prominent genera to receive attention as bioherbicide candidates include Colletotrichum, Phoma, and Sclerotinia. Among bacteria, Xanthomonas and Pseudomonas share this distinction. The available reports on the application of viruses to controlling weeds are also reviewed. Focus is given to the phytotoxic mechanisms associated with bioherbicide candidates. Achieving consistent suppression of weeds in field conditions is a common challenge to this control strategy, as the efficacy of a bioherbicide candidate is generally more sensitive to environmental variation than a conventional herbicide. Common themes and lessons emerging from the available literature in regard to this challenge are presented. Additionally, future directions for this crop protection strategy are suggested.

  4. Controlling weeds with fungi, bacteria and viruses: A review

    Directory of Open Access Journals (Sweden)

    Dylan Patrick Harding

    2015-08-01

    Full Text Available Weeds are a nuisance in a variety of land uses. The increasing prevalence of both herbicide resistant weeds and bans on cosmetic pesticide use has created a strong impetus to develop novel strategies for controlling weeds. The application of bacteria, fungi and viruses to achieving this goal has received increasingly great attention over the last three decades. Proposed benefits to this strategy include reduced environmental impact, increased target specificity, reduced development costs compared to conventional herbicides, and the identification of novel herbicidal mechanisms. This review focuses on examples from North America. Among fungi, the prominent genera to receive attention as bioherbicide candidates include Colletotrichum, Phoma, and Sclerotinia. Among bacteria, Xanthomonas and Pseudomonas share this distinction. The available reports on the application of viruses to controlling weeds are also reviewed. Focus is given to the phytotoxic mechanisms associated with bioherbicide candidates. Achieving consistent suppression of weeds in field conditions is a common challenge to this control strategy, as the efficacy of a bioherbicide candidate is generally more sensitive to environmental variation than a conventional herbicide. Common themes and lessons emerging from the available literature in regard to this challenge are presented. Additionally, future directions for this crop protection strategy are suggested.

  5. New possibilities for weed control in conventional soybeans

    Directory of Open Access Journals (Sweden)

    Petersen, Jan

    2014-02-01

    Full Text Available In field trials in was investigated, if the use of the in Germany new active ingredient imazamox enlarge the possibilities of post emergence weed control in soybeans. Furthermore new herbicide strategies were tested on efficacy and selectivity in soybeans. The use of imazamox was very selective and showed a relative broad spectrum of controlled weed species. However, efficacy of imazamox must be supported by a pre-emergence treatment and in most cases by a tank mix partner. For example cleavers (Galium aparine can not be controlled by imazamox. Tankmixtures of imazamox and bentazon indicated an antagonism. Efficacy to some weed species was reduced compared to solo application. The low dose concept – three applications of low doses at cotyledon stage of weeds led to some success. However, these strategies must be further investigated, before they can be recommended to commercial farming practice. All herbicide strategies tested showed some surviving weed species. This indicates that choice of herbicides, dose rates and application strategies must be done very careful and site specific.

  6. Critical Period of Weed Control in Corn (Zea mays L.

    Directory of Open Access Journals (Sweden)

    R Alizadeh

    2012-06-01

    Full Text Available In order to determine the critical peroid of weed control (CPWC in grain maize, a field study was conducted in 2008 in Agricultural Research Station of Esfahan province using a randomized complete block design with 12 treatments and three replications. The treatments consisted of two different periods of weed interference, a critical weed-free period and a critical time of weed removal were imposed at V3, V6, V9, V12, and R1 (based on phenological stages of corn development with a weedy check and a weed-free check. The CPWC was determined by fitting non-linear regression models of logistic and gompertz equations to the data in range of 2.5, 5, 10 and 15% of acceptable yield loss levels. The CPWC was from 1- to 13-leaf stage (2-54 DAE, 3- to 11-leaf stage (10-46 DAE, 5- to 8-leaf stage (20-35 DAE and 6-leaf stage (27 DAE in Esfahan condition to prevent yield losses of 2.5%, 5% , 10% and 15% respectively.

  7. Weed control using herbicides in short-rotation intensively cultured poplar plantations.

    Science.gov (United States)

    Edward A. Hansen; Daniel A. Netzer

    1985-01-01

    Summarizes a series of studies that investigated chemical weed control from time of planting to the end of the second growing season. The studies confirm the importance of weed control with preemergents at the time of planting and the importance of additional weed control before the start of the second growing season.

  8. Control of perennial weeds by mechanical methods and anaerobic soil disinfection

    NARCIS (Netherlands)

    Huiting, H.F.; Bleeker, P.O.; Riemens, M.M.

    2011-01-01

    Perennial weeds are difficult to control and ask for a specific approach. During the most recent years it has even become a great challenge to control these weeds in conventional farming systems, although in comparison effective perennial weed control in organic farming systems remains more difficul

  9. Weed control using ammonium nonanoate and cultivation in organic Vidalia sweet onion production

    Science.gov (United States)

    Ammonium nonanoate is registered for weed control in certified organic crop production and may be useful to control cool-season weeds in organic Vidalia® sweet onion. Cultivation with a tine weeder has been identified as a cost-effective means of weed control, but delays in cultivation cause some w...

  10. The critical period of weed control in corn Zea mays at Mashhad, Iran

    Directory of Open Access Journals (Sweden)

    majid abaspoor

    2009-06-01

    Full Text Available In order to determine the critical period of weed control in corn, an experiment was conducted at Research Station, Faculty of Agriculture, Ferdowsi University of Mashhad in year 2000. The experiment consisted of two discrete periods, a weed-free and a weed infested period. The weed-free period consisted of removing all weeds till 4th (19 days after planting, 7th (34 days after planting, 11th (48 days after planting, 13th (52 days after planting, and 17th (59 days after planting, leaf growth stages and weed free check for growing season (123 days after planting, and the critical time of weed infested consisted of removing all weeds from fourth (19 days after planting, 7th (34 days after planting, 11th (48 days after planting, 13th (52 days after planting, and 17th (59 days after planting, leaf growth stages and weedy infested check for growing season. All treatments were compared in a randomized complete block design with four replications. The results showed that by prolonging weed-infested period, dry matter and leaf surface area of weeds per square meter were increased, but by increasing weed-infested period, weed density was decreased. The lowest weed density (23 weed plants per m2 was shown at infested all period of corn growing season. By passing the growing season, C4 weed species such as red root pigweed and barnyard grass were dominant compared with C3 weed species. At weed infested all period of corn growing season, red root pigweed had the highest dry matter (93% of all weeds dry matter and leaf surface area (86% of all weeds leaf surface compared with other weed species. At the first treatment of critical weed-free (19 days after planting the regrowth of weeds were substantial which resulted in decreasing growth of corn. Grain yield of corn were significantly higher at 52, 59 and 123 days after planting in weed free treatments compared with 48, 52, 59 and 123 days after planting in weed infested treatments. However, there were no

  11. Herbaceous weed control in loblolly pine plantations using flazasulfuron

    Science.gov (United States)

    Andrew W. Ezell; Jimmie L. Yeiser

    2015-01-01

    A total of 13 treatments were applied at four sites (two in Mississippi and two in Texas) to evaluate the efficacy of flazasulfuron applied alone or in mixtures for providing control of herbaceous weeds. All sites were newly established loblolly pine (Pinus taeda L.) plantations. Plots were evaluated monthly until 180 days after treatment. No phytotoxicity on pine...

  12. Funding needed for assessments of weed biological control

    Science.gov (United States)

    John L. Maron; Dean E. Pearson; Stephen M. Hovick; Walter P. Carson

    2010-01-01

    Invasive non-native plants are a serious economic and ecological problem worldwide, and major efforts are therefore devoted to reducing weed abundance in agricultural and natural settings. Effective options for reducing invasive abundance and spread are few, although one common approach is biological control - the introduction of specialist herbivores or pathogens from...

  13. Acetic acid and weed control in onions (Allium cepa L.)

    Science.gov (United States)

    Weed control is a major challenge in conventional and organic production systems, especially for organically produced sweet onion (Allium cepa L.). Although corn gluten meal shows great promise as an organic preemergent herbicide for onions, research has shown the need for supplemental, postemergen...

  14. Potential of Air-Propelled Abrasives for Selective Weed Control

    Science.gov (United States)

    Novel forms of selective weed control are needed by many types of growers, but especially organic growers who are restricted from using synthetic herbicides. Abrasive grit made from corn cobs was expelled from a sand blaster at 517 kPa pressure and aimed at seedlings of common lambsquarters and corn...

  15. The Effect of Weeds Interference Time and Plant Density on Weeds Control and Broad Bean (Vicia faba L. Yield

    Directory of Open Access Journals (Sweden)

    M Dabaghzadeh

    2016-10-01

    m-2 of broad-beans, the highest frequency was recorded for mallow, clover and wild beet (15.2, 14.18 and 13.68 plants m-2. With the increased interference time period, from V9 broad-bean phenological stage on, the weed density was reduced due to "within species"(intra_species competition of weeds and "between species" (inter_species competition of weeds and the crop. As the time period of weeds interference increased, the dry weight reached its highest level, so that in full season weeding treatment, it reached 172.99 g m-2. Increasing the density of broad-bean from 8 to -14 plants m-2, decreased the weeds total dry weight from 92.42 to 83.76 g m-2 .Also increasing the weeds interference duration, reduced the seed yield, so that the highest yield, with the average of 2473.5 kg ha-1, was obtained in full season weeding treatments. Among the treatments of broad-bean density, the highest seed yield of 1342 kg ha-1 in average, was obtained from density treatment of 14 plants m-2. Among the treatments of interaction, weeds interference and Broad-bean density, Broad-bean density had a significant effect on the seed yield. The highest seed yield was observed in full season weeding treatment and the density of 14 plants m-2, with an average of 2699.87 kg ha-1, and the lowest seed yield was recorede in the treatment of full season interference and density of 14 plants m-2 with an average of 228.309 kg ha-1. Considering the results of this study, where weeding is not to be applied in V13 broad -bean phenological stage and next stages, the minimum density (8 plants m-2 is recommended, because density had no significant effect on broad-bean yield, this would reduce the cost of production. Conclusions It can be concluded that increasing the duration of weeds interference, reduced the seed yield and weeds density while it increased the weeds dry weight. Increased broad-bean density, also, reduced the density and dry weight of all the weeds. The best time to control weeds for

  16. Agronomic Weeds.

    Science.gov (United States)

    Hartwig, Nathan L.

    This agriculture extension service publication from Pennsylvania State University examines agronomic weed problems and control. Contents include a listing of the characteristics of weeds, a section on herbicides, and a section on the important weeds of agronomic crops in Pennsylvania. The herbicide section discusses systemic herbicides, contact…

  17. Agronomic Weeds.

    Science.gov (United States)

    Hartwig, Nathan L.

    This agriculture extension service publication from Pennsylvania State University examines agronomic weed problems and control. Contents include a listing of the characteristics of weeds, a section on herbicides, and a section on the important weeds of agronomic crops in Pennsylvania. The herbicide section discusses systemic herbicides, contact…

  18. Experience with GOLTIX® TITAN® controlling annual dicotyledonous weeds in beets

    Directory of Open Access Journals (Sweden)

    Fell, Martina

    2014-02-01

    Full Text Available The herbicide GOLTIX® TITAN® is the unique combination of two active ingredients, Metamitrone (525 g/L and Quinmerac (40 g/L. GOLTIX® TITAN® is used for the control of annual dicotyledonous weeds in sugar and fodder beets. Registration was granted for the post emergence splitting application with 3 x 2,0 L/ha (3 applications. This corresponds to the amount of 3150 g Metamitrone and 240 g Quinmerac per hectare at maximum application rate. The registration application for pre-emergence application has been submitted. Several field trials were carried out between 2009 and 2013. These trials revealed the optimized efficacy on important weeds in sugar beet production including Fool´s parsley (Aethusa cynapium, Cleavers (Gallium aparine and Fat-hen (Chenopodium album. Selectivity was examined in all of these trials and showed good results with all relevant mixtures at all application times. The two active ingredients have different modes of action; hence, the product plays an important role in resistance management. They can be applied flexibly and do not have any known negative influence on the environment. The successful formulation of this highly sophisticated sugar beet herbicide was confirmed by the available trial results. GOLTIX® TITAN® with its specified characteristics is the base for every weed control measure.

  19. The critical period of weed control in corn) Zea mays) at Mashhad, Iran

    OpenAIRE

    majid abaspoor; parviz rezvani moghadam

    2009-01-01

    In order to determine the critical period of weed control in corn, an experiment was conducted at Research Station, Faculty of Agriculture, Ferdowsi University of Mashhad in year 2000. The experiment consisted of two discrete periods, a weed-free and a weed infested period. The weed-free period consisted of removing all weeds till 4th (19 days after planting), 7th (34 days after planting), 11th (48 days after planting), 13th (52 days after planting), and 17th (59 days after planting), leaf gr...

  20. Weed control based on real time patchy application of herbicides using image analysis as a non-destructive estimation method for weed infestation and herbicide effects

    DEFF Research Database (Denmark)

    Asif, Ali

    There is an increasing concern about excessive use of herbicides for weed control in arable lands. Usually the whole field is sprayed uniformly, while the distribution of weeds often is non-uniform. Often there are spots in a field where weed pressure is very low and has no significant effect on ...... to estimate infestation of weeds at early growth stage. The image analysis method was further developed to estimate colour response of applying increasing doses of herbicides in selectivity experiments and to evaluate the weed-suppressing effect of mulches....

  1. Use of rhizobacteria and endophytes for biological control of weeds

    Directory of Open Access Journals (Sweden)

    Trognitz, Friederike

    2014-02-01

    Full Text Available Weeds cause severe yield losses in agriculture, with a maximum estimate of 34% of yield loss worldwide due to competition between the crops and the weeds for nutrition, light and humidity (OERKE, 2006. Invasive plants contribute partially to other problems. The pollen of common ragweed, Ambrosia artemisiifolia L., for example, is five times more allergenic than grass pollen; already ten pollen grains per m3 air can trigger allergy in sensitized patients, including rhinitis, conjunctivitis and asthma. This neophyte from America has extended the season of allergy in European patients to October. Common ragweed is currently most frequent in Hungary, France and Italy. In Austria, ragweed populations along roads have increased dramatically since 2000. The effective means to control this weed of the Asteraceae family are limited; a single plant can produce up to 6000 seeds which stay in the soil for 40 years. Control using selective herbicides is not possible within stands of the Asteraceae member sunflower. Efforts to use herbivore insects as biological control agents also failed due to the unavailability of insects specializing on this ragweed. The use of plant-associated rhizobacteria and endophytes as bio-herbicides offers a novel alternative to conventional methods. By analogy to experiences from other plant-microbe systems, the chances to find microbes of the desired characteristics are highest when isolating and testing specimens directly from ragweed plants. These organisms often have an extremely narrow host range that permits their use for the control of among several even closely related plant species growing together in a field.

  2. Determination of Optimum Weed Control Timing in Maize (Zea mays L.)

    OpenAIRE

    DOĞAN*, M. Nedim; ÜNAY, Aydın; BOZ, Özhan; ALBAY, Filiz

    2014-01-01

    In field experiments conducted in 2001 and 2002, the optimum timing for weed control in maize was investigated. Both experiments were designed according to randomized complete blocks, and Cyperus rotundus L., Amaranthus retroflexus L., Portulaca oleracea L. and Chenopodium album L. were naturally infested on experimental plots in both years. The study in 2001 was conducted to determine the critical period for weed control for maize. With this aim plots were maintained weed-free or weedy for ...

  3. Determination of Optimum Weed Control Timing in Maize (Zea mays L.)

    OpenAIRE

    DOĞAN*, M. Nedim; ÜNAY, Aydın; BOZ, Özhan; ALBAY, Filiz

    2004-01-01

    In field experiments conducted in 2001 and 2002, the optimum timing for weed control in maize was investigated. Both experiments were designed according to randomized complete blocks, and Cyperus rotundus L., Amaranthus retroflexus L., Portulaca oleracea L. and Chenopodium album L. were naturally infested on experimental plots in both years. The study in 2001 was conducted to determine the critical period for weed control for maize. With this aim plots were maintained weed-free or weedy for ...

  4. Controlling grass weeds on hard surfaces

    DEFF Research Database (Denmark)

    Rask, Anne Merete; Kristoffersen, Palle; Andreasen, Christian

    2012-01-01

    malezas gramíneas. El objetivo de este experimento fue optimizar el control de Poa annua y Lolium perenne, ambas especies muy difíciles de controlar sin herbicidas. La biomasa aérea de 72 plantas por tratamiento se cosechó y los pesos secos se registraron en intervalos regulares para investigar cómo las...... y también el índice de floración de las plantas de P. annua. Sin embargo, solamente murieron unas cuantas plantas. El primer tratamiento afectó la biomasa aérea más que el segundo tratamiento. Un intervalo entre tratamientos de siete días proporcionó la mayor reducción de regeneración de L. perenne...

  5. The role of plant-microbiome interactions in weed establishment and control.

    Science.gov (United States)

    Trognitz, Friederike; Hackl, Evelyn; Widhalm, Siegrid; Sessitsch, Angela

    2016-10-01

    The soil microbiome plays an important role in the establishment of weeds and invasive plants. They associate with microorganisms supporting their growth and health. Weed management strategies, like tillage and herbicide treatments, to control weeds generally alter soil structure going alongside with changes in the microbial community. Once a weed population establishes in the field, the plants build up a close relationship with the available microorganisms. Seeds or vegetative organs overwinter in soil and select early in the season their own microbiome before crop plants start to vegetate. Weed and crop plants compete for light, nutrition and water, but may differently interact with soil microorganisms. The development of new sequencing technologies for analyzing soil microbiomes has opened up the possibility for in depth analysis of the interaction between 'undesired' plants and crop plants under different management systems. These findings will help us to understand the functions of microorganisms involved in crop productivity and plant health, weed establishment and weed prevention. Exploitation of the knowledge offers the possibility to search for new biocontrol methods against weeds based on soil and plant-associated microorganisms. This review discusses the recent advances in understanding the functions of microbial communities for weed/invasive plant establishment and shows new ways to use plant-associated microorganisms to control weeds and invasive plants in different land management systems.

  6. Effects of nitrogen application method and weed control on corn yield and yield components.

    Science.gov (United States)

    Sepahvand, Pariya; Sajedi, Nurali; Mousavi, Seyed Karim; Ghiasvand, Mohsen

    2014-04-01

    The effects of nitrogen fertilizer application and different methods for weed control on yield and yield components of corn was evaluated in Khorramabad in 2011. The experiment was conducted as a split plot based on randomized complete block design in 3 replications. Nitrogen application was as main plot in 4 levels (no nitrogen, broadcasting nitrogen, banding nitrogen and sprayed nitrogen) and methods of weed control were in 4 levels (non-control weeds, application Equip herbicide, once hand control of weeds and application Equip herbicide+once time weeding) was as subplots. Result illustrated that effects of nitrogen fertilizer application were significant on grain and forage yield, 100 seeds weight, harvest index, grain number per row and cob weight per plant. Grain yield increased by 91.4 and 3.9% in application banding and broadcasting for nitrogen fertilizer, respectively, compared to the no fertilizer treatment. The results show improved efficiency of nitrogen utilization by banding application. Grain yield, harvest index, seed rows per cob, seeds per row and cob weight were increased by weed control. In the application of Equip herbicide+ hand weeding treatment corn grain yield was increased 126% in comparison to weedy control. It represents of the intense affects of weed competition with corn. The highest corn grain yield (6758 kg h(-1)) was related to the application banding of nitrogen fertilizer and Equip herbicide+once hand weeding.

  7. Critical period of weed control in oilseed rape in two Moroccan regions.

    Science.gov (United States)

    Maataoui, A; Bouhache, M; Benbella, M; Talouizte, A

    2003-01-01

    The determination of critical period of weed control in oilseed rape is necessary to know the weed control period. To determine the critical period, two fields experiments were carried out during 1995-96 growth season in Loukkos and Saïs regions at two oilseed densities (D1 = 24 and D2 = 36 plants m(-2)). Ten treatments corresponding to plots left weed free or weeded plots until four leaves, flowers bud, flowering, puds formation, and maturity stages of oilseed rape were tested. Density and biomass of weeds were determined at each oilseed stages. Results showed that weed density and biomass were higher in Saïs than in Loukkos sites. For a 10% yield loss, critical period of weed control in Loukkos was from 458 to 720 degree days after emergence (D degrees AE) and from 480 to 720 D degrees AE in oilseed conducted at densities D1 and D2, respectively. In Saïs, critical period of weed control was from 474 to 738 D degrees AE and from 468 to 675 D degrees AE in oilseed conducted at D1 and D2, respectively. It was concluded that the length of the critical period of weed control in oilseed rape grain yield seems to be dependant of the level of the infestation.

  8. Impact of the timing and duration of weed control on the establishment of a rubber tree plantation.

    Science.gov (United States)

    Guzzo, Caio D; Carvalho, Leonardo B de; Giancotti, Paulo R F; Alves, Pedro L C A; Gonçalves, Elaine C P; Martins, José V F

    2014-03-01

    Rubber tree production is reduced by weeds that compete for environmental resources; therefore, the timing and duration of weed control influences weed interference. The objectives of this study were to evaluate the growth of rubber tree (Hevea brasiliensis) plants, to determine the critical period for weed control, and to evaluate the growth recovery of rubber trees that coexisted with weeds for different periods of time after planting. Two groups of treatments were established under field conditions in the first year of the investigation: one group contained crescent periods of weed infestation, while the other contained crescent periods of weed control, also including a weed-free check and a total weedy check. In the second year of the investigation, the weeds were totally controlled. Urochloa decumbens was the dominant weed (over 90% groundcover). Crop growth was greatly reduced due to the weed interference. Plant height decreased more rapidly than did any other characteristic. Plant height, leaf dry mass, and leaf area decreased by 99%, 97% and 96%, respectively, and were the most reduced characteristics. Plant height also recovered more rapidly than did any characteristic when the period of weed control was lengthened. However, stem dry mass increased by 750%, making it the most recovered characteristic. The critical period for weed control was between 4 and 9½ months after planting in the first year; however, the rubber trees showed an expressive growth recovery when the weeds were controlled throughout the second year.

  9. Impact of the timing and duration of weed control on the establishment of a rubber tree plantation

    Directory of Open Access Journals (Sweden)

    CAIO D. GUZZO

    2014-03-01

    Full Text Available Rubber tree production is reduced by weeds that compete for environmental resources; therefore, the timing and duration of weed control influences weed interference. The objectives of this study were to evaluate the growth of rubber tree (Hevea brasiliensis plants, to determine the critical period for weed control, and to evaluate the growth recovery of rubber trees that coexisted with weeds for different periods of time after planting. Two groups of treatments were established under field conditions in the first year of the investigation: one group contained crescent periods of weed infestation, while the other contained crescent periods of weed control, also including a weed-free check and a total weedy check. In the second year of the investigation, the weeds were totally controlled. Urochloa decumbens was the dominant weed (over 90% groundcover. Crop growth was greatly reduced due to the weed interference. Plant height decreased more rapidly than did any other characteristic. Plant height, leaf dry mass, and leaf area decreased by 99%, 97% and 96%, respectively, and were the most reduced characteristics. Plant height also recovered more rapidly than did any characteristic when the period of weed control was lengthened. However, stem dry mass increased by 750%, making it the most recovered characteristic. The critical period for weed control was between 4 and 9½ months after planting in the first year; however, the rubber trees showed an expressive growth recovery when the weeds were controlled throughout the second year.

  10. Determination of critical period of weed control in rice (Oryza sativa L. in Lorestan province

    Directory of Open Access Journals (Sweden)

    abdolreza ahmadi

    2009-06-01

    Full Text Available Effects of different periods of weed control in paddy rice (Oryza sativa L. were studied in Veysian region of Lorestan province in 2004. The experiment was conducted in a randomized complete block design with four replications and 10 treatments of hand weeding in two series included weed free and weed infested plot up to 14, 28, 42 and 56 days after transplanting, plus weed free and weed infested control. Based on 5 and 10% acceptable yield loses, the critical periods were between 11 to 40 and 14 to 30 days after transplantation, respectively. Weed competition before and/or after these critical periods had negligible effects on grain yield of rice. This period, based on growing degree days (GDD was 198-768 GDD for 5% acceptable yield loss. Increasing periods of weed interference in the early stage of the crop resulted in a steady decline in grain yield. Yield losses equivalent to 47 kg/ha of grain resulted for each day that weed control was delayed between 14 and 28 days after transplanting.

  11. Weed control in sweet bell pepper using sequential postdirected applications of pelargonic acid

    Science.gov (United States)

    Pepper (Capsicum annuum) producers would benefit from additional herbicide options that are safe to the crop and provide effective weed control. Research was conducted in southeastern Oklahoma (Atoka County, Lane, OK) during 2010 and 2011 to determine the impact of pelargonic acid on weed control ef...

  12. Impact of mustard seed meal applications on direct-seeded cucurbits and weed control

    Science.gov (United States)

    Weed control in organic production systems can be a labor intensive and expensive process. Mustard seed meal (MSM) is phytotoxic and a potential pre-emergent and preplant-incorporated organic herbicide for controlling germinating and emerging weed seedlings: unfortunately, MSM may also adversely imp...

  13. Laboratory tests to assess optimal agricultural residue traits for an abrasive weed control system

    Science.gov (United States)

    One of the biggest challenges to organic agricultural production and herbicide resistant crops in industrialized countries today is the non-chemical control of weed plants. Studies of new tools and methods for weed control have been motivated by an increased consumer demand for organic produce and c...

  14. Broadcast applications of Acetic Acid: Weed control in spring-transplanted onions

    Science.gov (United States)

    Oklahoma producers are interested in sweet onion (Allium cepa L.) as an alternative crop for farm diversification, but weed control continues to be a primary obstacle. The weed control challenges for onion production are even greater for those considering organic crop production. The few organic h...

  15. Broadcast application of vinegar for broadleaf weed control in spring-transplanted onions

    Science.gov (United States)

    Vinegar (acetic acid) is a non-selective contact herbicide used in organic crop production. Research was conducted to determine if vinegar could be successfully applied over the top of onion plants to control broadleaf weeds. The experiment included 6 weed control treatments (2 application volumes...

  16. Growth of Loblolly Pine Treated With Hexazinone, Sulfometuron Methyl, and Metsulfuron Methyl For Herbaceous Weed Control

    Science.gov (United States)

    J.L. Michael

    1985-01-01

    Aerial application of 0.25 pounds active ingredient per acre of sulfometuron methyl [Oust(TM), formerly DPX-5648] of 2.0 pounds of hexazinone [Velpar L. (TM)] postmergent in May 1982, resulted in good weed control. Weeds controlled on the silly clay coastal plain soil included pokweed (Phytolacca americana L.) rugweed (Ambrosia sp...

  17. Weed control in distress – can all weeds still be controlled with herbicides in future?

    Directory of Open Access Journals (Sweden)

    Drobny, Hans G.

    2016-02-01

    Full Text Available The introduction and availability of highly active and selective herbicides in all important field crops, in the last decades, enabled the simplification and money saving in crop rotations and agronomic measures. This resulted in respective specialized and adapted weed populations, and consequently an increasing selection of resistant populations. Since the introduction of the ALS-inhibitors (starting 1985 and the 4-HPPD-inhibitors (2001, no new MoA-Classes were registered, and there are none in the registration process. Several established herbicides were not registered or re-registered in the EU, or were severely restricted in their application. The cost and the risk to develop and register a new selective herbicide in the EU are hardly justified, in relation to their market potential. The only solution on problem fields, with resistant populations, is to change the agronomic practices, like crop rotation, soil tillage, seeding time, etc., as a precautionary principle also on still „normal“ fields. The different advising institutions have to integrate these aspects into their recommendations, besides the proper herbicide management.

  18. EFFECT OF HERBICIDES ON WEED CONTROL AND YIELD OF WET SEEDED RICE (ORYZA SATIVA L.

    Directory of Open Access Journals (Sweden)

    MALLIKARJUN

    2014-06-01

    Full Text Available To study effect of herbicides on weed control and yield of wet seeded rice which involves three pre-emergent herbicides viz., butachlor, anilophos and oxyflurofen applied as alone and each these followed by two post emergent herbicides 2, 4- sodium salt, bispyribac sodium and one hand weeding at 25 days. The results revealed that sequential application of butachlor and anilophos fb bispyribac sodium, 2, 4-D sodium salt and one hand weeding at 25 days was recorded significantly lower weed population and dry weight of weeds viz., monocots, dicots and sedges in equal manner which ultimately indicates that higher weed control efficiency over rest of the treatments except weed free check and hand weeding thrice. further, grain and straw yield of rice was followed the same trend as well influenced by yield parameters like number of panicles per sq.m and number of seeds/ panicle ultimately sequential application butachlor and anilophos fb 2, 4-D sodium salt and bispyribac sodium and one hand weeding at 25 DAS resulted higher grain yield and profitable rice production.

  19. Weed control in dormant alfalfa (Medicago sativa L. with active ingredients’ metribuzin, imazetapyr and pronamide

    Directory of Open Access Journals (Sweden)

    Zvonko Pacanoski

    2017-03-01

    Full Text Available Field trials were conducted during 2008 – 2010 to evaluate weed control in dormant alfalfa (Medicago sativa L. with metribuzin, imazetapyr and pronamide. The weed population in all experimental years was consisted mainly of annual winter and spring grass and broadleaf weeds, and some perennial weeds. The number of weed species and weed density increased with the years of alfalfa growing, from second to the fourth year. Weed density in the untreated control plots was 201.0, 217.2 and 240.5 plants per m2 in 2008, 2009 and 2010, respectively. The most dominant weeds were Anthemis cotula, Capsell bursa-pastoris and Taraxacum officinale in 2008, Alopecurus myosuroides and Poa pratensis in 2009 and Millium vernale and Arabidopsis thaliana in 2010. Efficacy of herbicides in control of weeds was ranged of 91.8% (pronamide to 98.4% (metribuzin 1.0 kg*ha-1 in 2008, 93.1% (imazetapyr to 97.3% (metribuzin 1.0 kg*ha-1 in 2009 and 92.1% (imazetapyr to 97.3% (metribuzin 1.0 kg*ha-1 in 2010, respectively. Efficacy of herbicides in control of prevailing weeds during the 3 years field trial period was ranged of 48.5% to 100.0%. No visual alfalfa injured was determined by any rates during the experimental period, and consequently, none of the applied herbicides reduced first-harvest alfalfa yields. Alfalfa yield was markedly affected by herbicide efficacy in all experimental years, particularly in the second year, where yields of herbicide treatments were similar to that of the weed free control.

  20. Weed control methods effect on the hydraulic attributes of a Latosol

    Directory of Open Access Journals (Sweden)

    Luiz Fernando Pires

    2017-01-01

    Full Text Available Weed management plays a key role in the minimization of soil physical degradation processes such as compaction and hydric erosion. Different weed control managements can induce distinct changes in soil structure. One important soil physical attribute used for the analysis of modifications in soil structure is the soil water retention curve (SWRC. The objective of this work was to verify the use of physico-hydrical attributes to understand the effect of weed control managements on soil structure. Two soil layers (0–0.05 and 0.10–0.15 m and six weed control managements divided into two groups were analyzed: I. no soil disturbance and ground cover (no weed control, post-emergence herbicide, mechanical mower; and II. soil disturbance and no ground cover (hand-hoe weeding, rotary tiller, pre-emergence herbicide. An area of native forest was used as reference. The results showed that the volumetric water capacity derived from the SWRC can be an interesting tool to evaluate the impact of weed control managements on soil structure. Evaluations of the air-filled porosity variation for different pressure heads also presented interesting findings. Distinct results of the weed control managements were found for the different depths analyzed in relation to the forest.

  1. Weed Control Strategies for Organic Peanut Production and Transition: A Lesson in Basic Agronomy

    Science.gov (United States)

    Weed control in organic peanut production is difficult and costly. The only production inputs that consistently improved weed management in organic peanut production were modified production practices and intense cultivation with a tine weeder. Research trials evaluated row patterns, seeding rates...

  2. Air-propelled abrasive grit for postemergence in-row weed control in field corn

    Science.gov (United States)

    Organic growers need additional tools for weed control. A new technique involving abrasive grit propelled by compressed air was tested in field plots. Grit derived from corn cobs was directed at seedlings of summer annual weeds growing at the bases of corn plants when the corn was at differing early...

  3. Field Guide for the Biological Control of Weeds in Eastern North America

    Science.gov (United States)

    This field guide provides information about invasive weeds in Eastern North America and their associated biological control agents. Information about plant identification and ecology is provided through photographs and descriptions for each weed species. The guide also includes photographs of the bi...

  4. Releases of natural enemies in Hawaii since 1980 for classical biological control of weeds

    Science.gov (United States)

    P. Conant; J. N. Garcia; M. T. Johnson; W. T. Nagamine; C. K. Hirayama; G. P. Markin; R. L. Hill

    2013-01-01

    A comprehensive review of biological control of weeds in Hawaii was last published in 1992, covering 74 natural enemy species released from 1902 through 1980. The present review summarizes releases of 21 natural enemies targeting seven invasive weeds from 1981 to 2010. These projects were carried out by Hawaii Department of Agriculture (HDOA), USDA Forest Service (USFS...

  5. Controlling herbicide-susceptible, -tolerant and -resistant weeds with microbial bioherbicides

    Science.gov (United States)

    The management of weeds is a necessary but expensive challenge. Public concerns of health, safety, and sustainability have increased interest in reducing the use of synthetic chemicals for weed control. Alternatives to chemical herbicides, such as bioherbicides, may offer an alternative to herbicide...

  6. Effect of ecological management of weed control on economical income, yield and yield components of cotton (Gossypium hirsutum L.

    Directory of Open Access Journals (Sweden)

    A. Zare Feizabadi

    2016-04-01

    Full Text Available In order to compare of ecological management of weed control on economical income, yield and yield components of cotton (Gossypium hirsutum L., a Randomized Complete Block design with 12 treatments and four replications was conducted in Mahvelat of Khorasan Razavi province, Iran. Treatments consisted of weeding, harrowing, burning, two times weeding, weeding + harrowing, weeding + burning, harrowing + harrowing, harrowing + weeding, harrowing + burning, weeding+ harrowing+ burning, weed free and weedy as a check treatment. Investigated traits were plant height, number of boll in plant, 20 boll weight, 20 boll cotton lint weight, cotton lint yield per plant, cotton yield, number and biomass of weeds, outcome, net and gross income. The result showed that treatments had significant effect (p

  7. Rice Tolerance to Saflufenacil in Clomazone Weed Control Program

    Directory of Open Access Journals (Sweden)

    E. R. Camargo

    2011-01-01

    Full Text Available This research was conducted to evaluate (1 rice tolerance to saflufenacil applied preemergence (PRE and postemergence (POST and (2 the combination of saflufenacil and clomazone in light-textured soils. No injury from PRE application of saflufenacil was observed in 2009, and minimal injury for saflufenacil alone was observed in 2010. Injury as high as 68% was observed with combinations of 505 g ha−1 of clomazone applied PRE and 50 g ha−1 of saflufenacil applied POST in 2009 early evaluations. No interaction between clomazone and POST saflufenacil rates was observed in 2010. Rice injury intensified with increasing rates of saflufenacil applied POST. However, rice recovered with time for herbicide treatments applied PRE and POST in both years. Consequently, rice yield was not affected by any of the saflufenacil rates applied either PRE or POST in a clomazone weed control program.

  8. Designing, modeling and controlling a novel autonomous laser weeding system

    DEFF Research Database (Denmark)

    Shahrak Nadimi, Esmaeil; Andersson, Kim Johan; Jørgensen, Rasmus Nyholm

    2009-01-01

      Abstract: in this paper, the process of designing and developing a novel laser weeding test setup is explained. The main purpose of designing this system was to simulate the dynamic field conditions of a mobile vehicle capable of targeting weeds. This system consists of a rig containing three...

  9. Managing invasive plants in natural areas: Moving beyond weed control

    Science.gov (United States)

    Dean Pearson; Yvette Ortega

    2009-01-01

    Exotic invasive plants present one of the greatest challenges to natural resource management. These weeds can alter entire communities and ecosystems, substantially degrading important ecosystem services such as forage for wild and domestic herbivores, water and soil quality, recreational values, and wildlife habitat. Traditionally, weed management in natural areas has...

  10. Cover crop residue management for optimizing weed control

    NARCIS (Netherlands)

    Kruidhof, H.M.; Bastiaans, L.; Kropff, M.J.

    2009-01-01

    Although residue management seems a key factor in residue-mediated weed suppression, very few studies have systematically compared the influence of different residue management strategies on the establishment of crop and weed species. We evaluated the effect of several methods of pre-treatment and p

  11. The Use of Weed Control Robot (WCR for Achieve to the Sustainable Agriculture

    Directory of Open Access Journals (Sweden)

    Behzad Sani

    2013-10-01

    Full Text Available Today, weeds control is very difficult because they are resistant to the herbicide due to excessive use of chemical herbicides in agriculture. Many studies have shown that mechanical and biological control of weeds can be much less damage to the environment of chemical herbicides. Develop of biological herbicides in agriculture was slow due to high prices and this subject the researchers to move toward the elimination of agricultural weed mechanically. This work was originally done by a many number of workers because and workers' rights didn’t work was ultimately economic value. Now solve this subject by the use of robotic technology in agriculture has been studied and a many number of agricultural researchers with the help of computer scientists move towards making robots to remove the weeds. Of course this is difficult due to excessive weeds similar to the plants, but the final results will help to increase crop and save the environment by eliminating chemical herbicides.

  12. Efficacy of Apirus, Total, Atlantis and Chevalier Herbicides on Weed Control in Wheat

    Directory of Open Access Journals (Sweden)

    B. Malekian

    2016-07-01

    Full Text Available In order to investigate the effect of Apirus, Total, Atlantis and Chevalier herbicides at different doses on winter wheat, a two-year field experiment was conducted in Research Farm of College of Agriculture, Shiraz University, during 2011-2012 and 2012-2013 growing seasons. The experimental design was a randomized complete blocks with four replications. Treatments were Apirus at 24, 27 and 30 g ha-1, Total at 35, 40 and 45 g ha-1, Atlantis at 1.2, 1.5 and 1.8 L ha-1, Chevalier at 300, 400 and 500 g ha-1, and two weedy and weed free checks. The results showed that application of herbicides in both growing seasons reduced weed dry matter and weeds density compared to the weedy check. Among herbicide treatments, Total at 45 g ha-1, reduced weeds dry matter by 95.9 and 100% that was not significantly different from other doses. Application of Chevalier herbicide, especially at 300 g ha-1, decreased wheat yield compared to the weed free check and did not provide acceptable weed control. The present study showed that Total herbicide was more efficient than other treatments in terms of weed control even at limited doses, and it could be recommended to farmers under Shiraz climatic condition. Further researches for understanding efficacy of these herbicides in winter wheat in different weed densities are recommended.

  13. Efficacy evaluation of selected herbicides on weed control and productivity evaluation of Bt cotton in Punjab.

    Science.gov (United States)

    Singh, Kulvir; Rathore, Pankaj

    2015-07-01

    Field experiments were conducted during Kharif 2012 and 2013 to evaluate the efficacy of different herbicides for weed management in cotton. Highest seed cotton yield (3537.3 kg ha(-1)) was recorded in weed free plots followed by pendimethalin @1.0 kg a.i ha(-1) as Pre.em.+quizalofopethyl @50 g a.i ha(-1) post-em at 2-4 weed leaf stage + one hoeing (3318.9 kg ha") owing to improved number of bolls per plant and boll weight. Statistically least yield was recorded underweedy check (1435.4 kg ha(-1)). Application of pyrithiobac sodium could not express any visible toxic effect on crop indicating its selectivity for cotton, although none of the tested new chemicals i.e., pyrithiobac sodium@ 62.5g a.i ha(-1) and quizalofopethyl @50g a.i ha(-1) when applied alone could not outperform the existing recommended chemicals for weed management. Yield losses to the extent of 6.2-59.4% were recorded due to weed competition. Weed control efficiency (WCE) was highest under weed free check (86.8%) followed by pendimethalin @1.0 kg a.i ha(-1) as Pre. em.+quizalofopethyl @50g a.i ha(-1), at 2-4 weed leaf stage + one hoeing (73.7%), whereas minimum values were for weedy check (24.7%). Though net returns (r94660 ha(-1)) were highest for weed free check but higher B:C ratio (2:11) was observed for pendimethalin @1.0 kg a.i ha(-1) as Pre em.+quizalofopethyl @50 g a.i ha(-1) post-em at 2-4 weed leaf stage+one hoeing. Therefore, for reasons such as labor shortage besides their timely availability, using these herbicides in combination with cultural practices could be the practical solution foreconomically efficient and effective weed management.

  14. New weed control strategies in maize considering narrow crop rotations with maize, greater ALSresistance in common weeds and application restrictions with regard to active substance

    Directory of Open Access Journals (Sweden)

    Ewert, Katrin

    2014-02-01

    Full Text Available Many herbicides with different HRAC-groups are available for weed control in maize. Because of narrow maize crop rotation summer weeds and warmth loving weeds are encouraged. On the other hand the new confirmed cases of an ALS target site resistance in the weed species Echinochloa crus-galli and Amaranthus retroflexus in Brandenburg, Stellaria media in Saxony and Matricaria recutita and Tripleurospermum perforatum in Brandenburg and Thuringia, warn that in the future the sulfonylureas must be used only according to the management of herbicide resistance. In this way the selection of resistant weed biotypes will be prevented. Moreover in protected water areas it may be a requirement to reduce and to substitute the input of some active substances, for example terbuthylazine and bentazon. The control of E. crus-galli and P. convolvulus with non-sulfonylurea or/and non-terbuthylazine herbicides according to management of herbicide resistance will be discussed.

  15. Estimating economic thresholds for site-specific weed control using manual weed counts and sensor technology: an example based on three winter wheat trials.

    Science.gov (United States)

    Keller, Martina; Gutjahr, Christoph; Möhring, Jens; Weis, Martin; Sökefeld, Markus; Gerhards, Roland

    2014-02-01

    Precision experimental design uses the natural heterogeneity of agricultural fields and combines sensor technology with linear mixed models to estimate the effect of weeds, soil properties and herbicide on yield. These estimates can be used to derive economic thresholds. Three field trials are presented using the precision experimental design in winter wheat. Weed densities were determined by manual sampling and bi-spectral cameras, yield and soil properties were mapped. Galium aparine, other broad-leaved weeds and Alopecurus myosuroides reduced yield by 17.5, 1.2 and 12.4 kg ha(-1) plant(-1)  m(2) in one trial. The determined thresholds for site-specific weed control with independently applied herbicides were 4, 48 and 12 plants m(-2), respectively. Spring drought reduced yield effects of weeds considerably in one trial, since water became yield limiting. A negative herbicide effect on the crop was negligible, except in one trial, in which the herbicide mixture tended to reduce yield by 0.6 t ha(-1). Bi-spectral cameras for weed counting were of limited use and still need improvement. Nevertheless, large weed patches were correctly identified. The current paper presents a new approach to conducting field trials and deriving decision rules for weed control in farmers' fields. © 2013 Society of Chemical Industry.

  16. Evaluation of yield quality and weed infestation of common valerian (Valeriana officinalis L. in dependence on weed control method and forecrop.

    Directory of Open Access Journals (Sweden)

    Cezary Kwiatkowski

    2012-12-01

    Full Text Available A field experiment involving the cultivation of common valerian was conducted on loess soil in Abramów (Lublin region in the period 2007-2009. Qualitative parameters of herbal raw material obtained from this plant as well as in-crop weed infestation were evaluated depending on the protection method and forecrop. Hand-weeded plots, in which a hand hoe was used, were the control. In the other treatments, weeds were controlled using various herbicides and a mechanical implement (brush weeder. Potato and winter wheat + field pea cover crop were the forecrops for common valerian crops. A hypothesis was made that the use of a brush weeder and herbicides not registered for application in valerian crops would have a positive effect on this plant's productivity and weed infestation in its crops. It was also assumed that the introduction of a cover crop would allow the elimination of differences in the forecrop value of the crop stands in question. The best quantitative and qualitative parameters of common valerian raw material as well as the largest reduction of incrop weed infestation were recorded after the application of the herbicides which were not type approved. The use of the brush weeder in the interrows also had a beneficial effect on productivity of the plant in question, but secondary weed infestation at the end of the growing season of common valerian turned out to be its disadvantage. Traditional crop protection methods used in common valerian crops were less effective in weed infestation reduction and they resulted in lower plant productivity and raw material quality. Potato proved to be a better forecrop for common valerian than winter wheat + field pea; however, this positive effect was not confirmed statistically. The following annual weeds: Chenopodium album, Galinsoga parviflora, Stellaria media, were predominant in the common valerian crop. Traditional weed control methods resulted in the dominance of some dicotyledonous weeds, such

  17. EFFECT OF SETTING THE PARAMETERS OF FLAME WEEDER ON WEED CONTROL EFFECTIVENESS

    Directory of Open Access Journals (Sweden)

    Miroslav Mojžiš

    2013-12-01

    Full Text Available Unconventional ways of growing plants, when we return to non-chemical methods of controlling weeds, require new weed control methods. One of the few physical methods, which found wider application in practice, is a flame weeder with heat burners based on the use of gas (LPG. However, the process of practical use of this flame weeder has a number of factors that positively or negatively affect the effectiveness of weed control. A precise setting of flame weeders is influenced, for example by weed species, weed growth stage, weather, type of crop grown, but also heat transmission and heat absorption by plant. Many variables that enter into the process must be eliminated for their negative impacts on achieving the best results in fighting against weeds. In this paper, we have focused on naming these parameters, on field trials that confirm the justification of the precise setting of parameters, and recommendations for practice to achieve a higher efficiency of thermal weed control.

  18. Row Spacing Determines Critical Period of Weed Control in Crop: Cowpea (Vigna unguiculata) as a Case Study

    OpenAIRE

    Omobolanle Adewale Osipitan; Joseph Aremu Adigun; Rauf Olabisi Kolawole

    2016-01-01

    To further understand the importance of row spacing as an agronomic practice, a study was conducted to evaluate how levels of row spacing determines the critical period of weed control (CPWC) in cowpea (Vigna unguiculata). The experiment was laid out as a split-plot design with eight periods of weed interference as the main plots and three row spacing (60, 75 90 cm) as the subplots with three replications of each treatment combination. Period of weed interference consisted of weed removal for...

  19. Controlling annual weeds in cereals by deploying crop rotation at the landscape scale: Avena sterilis as an example.

    Science.gov (United States)

    González-Díaz, Lucía; van den Berg, Femke; van den Bosch, Frank; González-Andújar, José Luis

    2012-04-01

    Weed control through crop rotation has mainly been studied in a nonspatial context. However, weed seeds are often spread beyond the crop field by a variety of vectors. For weed control to be successful, weed management should thus be evaluated at the landscape level. In this paper we assess how seed dispersal affects the interactions between crop rotation and landscape heterogeneity schemes with regard to weed control. A spatially explicit landscape model was developed to study both short- and long-term weed population dynamics under different management scenarios. We allowed for both two- and three-crop species rotations and three levels of between-field weed seed dispersal. All rotation scenarios and seed dispersal fractions were analyzed for both completely homogeneous landscapes and heterogeneous landscapes in which more than one crop was present. The potential of implementing new weed control methods was also analyzed. The model results suggest that, like crop rotation at the field level, crop rotation implemented at the landscape level has great potential to control weeds, whereby both the number of crop species and the cropping sequence within the crop rotation have significant effects on both the short- and long-term weed population densities. In the absence of seed dispersal, weed populations became extinct when the fraction of each crop in the landscape was randomized. In general, weed seed densities increased in landscapes with increasing similarity in crop proportions, but in these landscapes the level of seed dispersal affected which three-crop species rotation sequence was most efficient at controlling the weed densities. We show that ignoring seed dispersal between fields might lead to the selection of suboptimal tactics and that homogeneous crop field patches that follow a specific crop rotation sequence might be the most sustainable method of weed control. Effective weed control through crop rotation thus requires coordination between farmers with

  20. Cultural control of weeds in herbicide-free annual forages

    Science.gov (United States)

    The adoption of zero tillage systems improves soil water conservation, allowing for increased crop intensification and diversification in the semiarid northern Great Plains. Zero tillage systems rely primarily on herbicides for weed management, increasing selection pressure for herbicide resistance...

  1. FruitGrowth - Gasburning in Orchards - Environment friendly weed control

    DEFF Research Database (Denmark)

    Bertelsen, Keld Kjærhus; Duzel, Jasmin; Nielsen, Søren Hundevadt

    Gas burning makes treatment of weed organic. The new ENVO-DAN burner saves 40% gas and treats ½ meter in width. It can be mounted on a standard lawn tractor, orchard tractor or a mobile robot.......Gas burning makes treatment of weed organic. The new ENVO-DAN burner saves 40% gas and treats ½ meter in width. It can be mounted on a standard lawn tractor, orchard tractor or a mobile robot....

  2. Non-chemical Control of Root Parasitic Weeds with Biochar

    Directory of Open Access Journals (Sweden)

    Hanan Eizenberg

    2017-06-01

    Full Text Available This study tested whether soil-applied biochar can impact the seed germination and attachment of root parasitic weeds. Three hypotheses were evaluated: (i biochar adsorbs host-exuded signaling molecules; (ii biochar activates plants’ innate system-wide defenses against invasion by the parasite; and (iii biochar has a systemic influence on the amount of seed germination stimulant produced or released by the host plant. Three types of experiments were performed: (I pot trials with tomato (Solanum lycopersicum infested with Phelipanche aegyptiaca PERS. (Egyptian broomrape and three different types of biochar at concentrations ranging from 0 to 1.5% weight, wherein tomato plant biomass, P. aegyptiaca biomass, and number of P. aegyptiaca-tomato root attachments were quantified; (II split-root biochar/no-biochar experiments under hydroponic growing conditions performed in polyethylene bags with tomato plant rootings, wherein P. aegyptiaca seed germination percentage and radicle attachment numbers were quantified; and (III germination trials, wherein the effect of biochar adsorption of GR-24 (artificial germination stimulant on P. aegyptiaca seed germination was quantified. Addition of biochar to the pot soil (Experiment I resulted in lower levels of P. aegyptiaca infection in the tomato plants, mainly through a decrease in the number of P. aegyptiaca attachments. This led to improved tomato plant growth. In Experiment II, P. aegyptiaca seed germination percentage decreased in the biochar-treated root zone as compared with the no-biochar control root zone; P. aegyptiaca radicle attachment numbers decreased accordingly. This experiment showed that biochar did not induce a systemic change in the activity of the stimulant molecules exuded by the tomato roots, toxicity to the radicles, or a change in the ability of the radicles to penetrate the tomato roots. The major cause for the decrease in germination percentage was physical adsorption of the

  3. The critical period of weed control in soybean (Glycine max (L.) Merr.) in north of Iran conditions.

    Science.gov (United States)

    Keramati, Sara; Pirdashti, Hemmatollah; Esmaili, Mohammad Ali; Abbasian, Arastoo; Habibi, Marjaneh

    2008-02-01

    A field study was conducted in 2006 at Sari Agricultural and Natural Resources University, in order to determine the best time for weed control in soybean promising line, 033. Experiment was arranged in randomized complete block design with 4 replications and two series of treatments. In the first series, weeds were kept in place until crop reached V2 (second trifoliolate), V4 (fourth trifoliolate), V6 (sixth trifoliolate), R1 (beginning bloom, first flower), R3 (beginning pod), R5 (beginning seed) and were then removed and the crop kept weed-free for the rest of the season. In the second series, crops were kept weed-free until the above growth stages after which weeds were allowed to grow in the plots for the rest of the season. Whole season weedy and weed-free plots were included in the experiment for yield comparison. The results showed that among studied traits, grain yield, pod numbers per plant and weed biomass were affected significantly by control and interference treatments. The highest number of pods per plant was obtained from plots which kept weed-free for whole season control. Results showed that weed control should be carried out between V2 (26 day after planting) to R1 (63 day after planting) stages of soybean to provide maximum grain yield. Thus, it is possible to optimize the timing of weed control, which can serve to reduce the costs and side effects of intensive chemical weed control.

  4. CHEMICAL WEED CONTROL IN OIL PUMPKIN (CUCURBITA PEPO L. VAR. OLEIFERA PIETSCH

    Directory of Open Access Journals (Sweden)

    Zdenko Besek

    2012-06-01

    Full Text Available A two-year experiment (2002 – 2003 was conducted in oil pumpkin (Cucurbita pepo var. oleifera at two localities (Vranjevo and Poljanice to evaluate the effectiveness of chemical weed control through application of herbicides, and to compare it with mechanical weed control. Main weeds were Amaranthus retroflexus, Setaria viridis and Echinochloa crus-galli. All herbicide treatments, except combination of prometrine + fluazifop-p butyl36, in 2002 appeared to be acceptable to high efficacy in control of annual grass- and broad-leaved weeds. The efficacy of all herbicide treatments in 2003 was lower. The best results of herbicide effectiveness were achieved with combination of linuron + dimethenamid (91.3%, trifluralin (90.1% + napropamide and clomazone + linuron (89%.

  5. Ecophysiological responses of a young blue gum (Eucalyptus globulus) plantation to weed control.

    Science.gov (United States)

    Eyles, Alieta; Worledge, Dale; Sands, Peter; Ottenschlaeger, Maria L; Paterson, Steve C; Mendham, Daniel; O'Grady, Anthony P

    2012-08-01

    Early weed control may improve the growth of forest plantations by influencing soil water and nutrient availability. To understand eucalypt growth responses to weed control, we examined the temporal responses of leaf gas-exchange, leaf nitrogen concentration (N) and water status of 7-month-old Eucalyptus globulus L. trees in a paired-plot field trial. In addition, we monitored the growth, leaf N and water status of the competing vegetation in the weed treatment. By the end of the 11-month experiment, complete weed control (WF treatment) of largely woody competitors increased the basal diameter of E. globulus by 14%. As indicated by pre-dawn water potentials of > - 0.05 MPa, interspecies competition for water resources was minimal at this site. In contrast, competition for N appeared to be the major factor limiting growth. Estimations of total plot leaf N (g m(-2) ground) showed that competing vegetation accounted for up to 70% of the total leaf N at the start of the trial. This value fell to 15% by the end of the trial. Despite increased leaf N(area) in WF trees 5 months after imposition of weed control, the photosynthetic capacity (A(1500)) of E. globulus was unaffected by treatment suggesting that the growth gains from weed control were largely unrelated to changes in leaf-level photosynthesis. Increased nutrient availability brought about by weed control enabled trees to increase investment into leaf-area production. Estimates of whole-tree carbon budget based on direct measurements of dark respiration and A(1500) allowed us to clearly demonstrate the importance of leaf area driving greater productivity following early weed control in a nutrient-limited site.

  6. Mechanical weed control on small-size dry bean and its response to cross-flaming

    Energy Technology Data Exchange (ETDEWEB)

    Martelloni, L.; Frasconi, C.; Fontanelli, M.; Raffaelli, M.; Peruzzi, A.

    2016-11-01

    Dry bean (Phaseolus vulgaris L.) can be a profitable crop for farmers; however controlling weeds effectively without a decrease in yield remains a problem. An example where mechanical weed control is difficult to conduct is dry bean ‘Toscanello’, which is a small sized high-income niche product growing low to the ground. Concerning intra-row weed control, also flame weeding could be an opportunity but the dry bean heat tolerance needs to be studied. The aims of this research were to study the weed control efficacy of a spring-tine harrow and an inter-row cultivator in this bean variety, and to test the tolerance of dry bean cultivated under weed-free conditions to cross-flaming applied with different liquefied petroleum gas (LPG) doses. Flame weeding was applied at BBCH 13 and BBCH 14 bean growth stages by pairs of burners producing direct double flame acting into the intra-row space, with bean plants placed in the middle. The results suggest that the spring-tine harrow used two times at BBCH 13 and 14, respectively, lead to a yield similar to that of the weedy control. The inter-row cultivator could be an opportunity for small-sized dry bean crops producers, enabling them to obtain a similar yield compared to the hand-weeded control. Concerning the bean tolerance to cross-flaming the results showed that bean flamed at BBCH 13 stage had little tolerance to cross-flaming. Bean flamed at BBCH 14 stage was tolerant until an LPG dose of 39 kg/ha, giving yield responses similar to those observed in the non-flamed control. (Author)

  7. Cruciferous weeds in oil seed rape – appearance and control

    Directory of Open Access Journals (Sweden)

    Klingenhagen, Günter

    2014-02-01

    Full Text Available Different cruciferous weeds were drilled in autumn 2011 and 2012 in a field near Münster. Beside common species like hedge mustard (Sisymbrium officinale Scop., shepherd`s purse (Capsella bursa-pastoris, pennycress (Thlaspiarvense, tall hedge mustard (Sisymbrium loeselii and flixweed (Descurainia sophia, we tried to establish weeds that are not common on arable land in Germany until now. These were: Yellow rocket (Barbarea vulgaris, hoary cress (Lepidium draba and Turkish rocket (Bunias orientalis. In autumn 2011 emergence of the sown weeds was poor. In the second year of experiment we got good emergence of the named weeds excluding hoary cress (Lepidium draba. In autumn 2011 and 2012 different herbicidecombinations were applied across the stripes. The best results were achieved with Colzor Trio (clomazone + dimethachlor + napropamid which was applied in pre-emergence state, a spray sequence Butisan Gold (metazachlor + quinmerac + dimethenamid-P applied in pre-emergence followed by Salsa (ethametsulfuronmethyl + Trend (adjuvant in post-emergence and Clearfield-Vantiga (metazachlor + quinmerac + imazamox + Dash (adjuvant, also applied in post-emergence state of the weeds.

  8. Response of faba bean to phosphate fertilizer and weed control on nitisols of ethiopian highlands

    Directory of Open Access Journals (Sweden)

    Getachew Agegnehu

    Full Text Available The effects of phosphorus fertilizer and weed control on yield and major yield components of faba bean (Vicia faba L. were studied on Nitisols of Ethiopian highlands. Factorial combinations of four levels of phosphorus fertilizer (0, 10, 20 and 30 kg P ha-1 as triple super phosphate (TSP and two levels of weeding (W1 = no weeding and W2 = hand weeding once six weeks after crop emergence were laid out in randomized complete block design with three replications. Results indicated that highly significant positive responses of number of pods per plant, total biomass and seed yields of faba bean to phosphorus fertilizer and weeding treatments were noted. Phosphorus level × weed control interaction over three years significantly (P ≤ 0.05 affected faba bean seed yield at Rob Gebeya but not at Welmera. Phosphorus application at the rates of 10, 20 and 30 kg P ha-1 resulted in mean seed yield increases compared to the control of 20, 41 and 53%, respectively on the average of locations; 13, 33 and 51%, respectively at Welmera, and 26, 48 and 55%, respectively at Rob Gebeya.Weeding once increased mean seed yields of faba bean by 25% on the average (35 and 17% at Welmera and Rob Gebeya, respectively compared to unweeded check. Seed yield was positively correlated with total biomass and number of pods per plant (r = 0.95*** and 0.75***, respectively at Welmera, and (r = 0.94*** and 0.55**, respectively at Rob Gebeya. The results of economic analysis indicated that the highest marginal rate of return was obtained from weeding once six weeks after crop emergence and application of 20 kg P ha-1, which is economically the most feasible alternative on Nitisols of central Ethiopian highlands.

  9. Introduction to Weeds and Herbicides.

    Science.gov (United States)

    Hartwig, Nathan L.

    This agriculture extension service publication from Pennsylvania State University is an introduction to weed control and herbicide use. An initial discussion of the characteristics of weeds includes scientific naming, weed competition with crops, weed dispersal and dormancy, and conditions affecting weed seed germination. The main body of the…

  10. Introduction to Weeds and Herbicides.

    Science.gov (United States)

    Hartwig, Nathan L.

    This agriculture extension service publication from Pennsylvania State University is an introduction to weed control and herbicide use. An initial discussion of the characteristics of weeds includes scientific naming, weed competition with crops, weed dispersal and dormancy, and conditions affecting weed seed germination. The main body of the…

  11. Damage and Control of Poisonous Weeds in Western Grassland of China

    Institute of Scientific and Technical Information of China (English)

    ZHAO Bao-yu; SHI Zhi-cheng; LIU Zhong-yan; LU Hao; WANG Zhan-xin; SUN Li-sha; WAN Xue-pan; GUO Xi; ZHAO Yan-tao; WANG Jian-jun

    2010-01-01

    Western grassland is the main source of living and means of production of western inhabitants. For many years,desertification and poisonous-weeds growth in grassland were resulted from over-grazing, over-reclaiming, over-spading and population growth. Western natural ecological environment is destroyed severly. Meanwhile, it has restricted the sustainable development of animal husbandry. The fast spreading poisonous-weeds, which caused grassland ecology unbalance, is one of the considerable bioecology problems and an important index of grassland degeneration. Based on analysis and induction of previous data, this article introduced the situation of poisonous-weeds disaster of western grassland in recent decades, category and distribution of poisonous-weeds, integrated control and reasonable utilization.

  12. Robotic weeding and automated weed measurements

    DEFF Research Database (Denmark)

    Christensen, S.; Søgaard, H.T.; Jørgensen, R.N.

    2003-01-01

    The goal of decreasing herbicide usage has so far focused on reducing the herbicide dosage or replacing chemical weed control by hoeing and harrowing. The conventional weed control strategy is to apply the same dose of herbicide or the same intensity of hoeing and harrowing in the whole field....... The strategy may be changed in the coming years because experiments in Germany, USA, Australia, and Denmark have shown that site-specific weed management can reduce herbicide usage significantly. One of the promising technologies for site specific weed management is robotic weeding. This paper reviews...... the state-of-the-art of automated weed measurement methods and the research projects concerning autonomous platform and information system for crop and weed monitoring and robotic weeding....

  13. Agronomic evaluation of cowpea as a function of weed control with herbicides and different combinations

    Directory of Open Access Journals (Sweden)

    Wando Wilson de Oliveira Souza

    2016-12-01

    Full Text Available ABSTRACT Cultivation of the cowpea is important in various regions of Brazil, but competition from weeds is one of the factors which limit productivity. The aim of this study therefore was to evaluate the pre-plant selectivity and efficiency of different herbicides, and combinations of herbicides, in the cowpea [Vigna unguiculata (L. Walp.]. An experiment was carried out in a randomised block design, in lots split over time and with three replications, using a 4 x 7 factorial scheme, where the treatments consisted of: glyphosate, glyphosate + imazethapyr, glyphosate + flumioxazin, glyphosate + imazethapyr + flumioxazin, glyphosate + ready mix (imazethapyr & flumioxazin, and two control treatments (one with no weeding and one with manual weeding. The treatments were evaluated in combination with four different sowing times, i.e. immediately after application of the herbicides, and at five, ten and fifteen days after application (DAA. The combination of glyphosate + flumioxazin at 15 DAA, gave the highest mean productivity, 1,105.32 kg ha-1, followed by manual weeding with 1,027.37 kg ha-1. The herbicide mixtures of glyphosate + imazethapyr + flumioxazin caused phyto-toxicity in the cowpea crop, limiting the production components. The best strategies for weed control in this crop are manual weeding with seeding at 10 DAA, as well as the application of a glyphosate + flumioxazin mixture with seeding at 15 DAA.

  14. Assessing the impact of revegetation and weed control on urban sensitive bird species.

    Science.gov (United States)

    Archibald, Carla L; McKinney, Matthew; Mustin, Karen; Shanahan, Danielle F; Possingham, Hugh P

    2017-06-01

    Nature in cities is concentrated in urban green spaces, which are key areas for urban biodiversity and also important areas to connect people with nature. To conserve urban biodiversity within these natural refugia, habitat restoration such as weed control and revegetation is often implemented. These actions are expected to benefit biodiversity, although species known to be affected by urbanization may not be interacting with restoration in the ways we anticipate. In this study, we use a case study to explore how urban restoration activities impact different bird species. Birds were grouped into urban sensitivity categories and species abundance, and richness was then calculated using a hierarchical species community model for individual species responses, with "urban class" used as the hierarchical parameter. We highlight variable responses of birds to revegetation and weed control based on their level of urban sensitivity. Revegetation of open grassy areas delivers significant bird conservation outcomes, but the effects of weed control are neutral or in some cases negative. Specifically, the species most reliant on remnant vegetation in cities seem to remain stable or decline in abundance in areas with weed control, which we suspect is the result of a simplification of the understorey. The literature reports mixed benefits of weed control between taxa and between locations. We recommend, in our case study site, that weed control be implemented in concert with replanting of native vegetation to provide the understory structure preferred by urban sensitive birds. Understanding the impacts of revegetation and weed control on different bird species is important information for practitioners to make restoration decisions about the allocation of funds for conservation action. This new knowledge can be used both for threatened species and invasive species management.

  15. Organic Weed Control in White Lupin (Lupinus albus L.)

    Science.gov (United States)

    Legumes such as white lupin (Lupinus albus L.) provide a valuable nitrogen source in organic agriculture. With organic farming becoming an increasing sector of US agriculture and white lupin interest increasing in the southeastern USA because winter hardy cultivars are available, non-chemical weed c...

  16. Selectivity and weed control efficacy of some herbicides applied to sprinkler irrigated rice (Oryza sativa L.)

    Energy Technology Data Exchange (ETDEWEB)

    Cavero, J.; Zaragoza, C.; Cirujeda, A.; Anzalone, A.; Faci, J. M.; Blanco, O.

    2011-07-01

    Sprinkler irrigation can reduce the irrigation water needed to grow rice. However, most available information on weed control with herbicides is related to flood irrigated rice because this is the main growing method. Field experiments were conducted at Zaragoza (Spain) during two years to study weed control and tolerance of sprinkler irrigated rice to several herbicides. The main weeds were Atriplex prostrata Boucher ex DC., Cyperus rotundus L., Echinochloa crus-galli (L.) Beauv. and Sonchus oleraceus L. Rice cv Guadiamar was tolerant to preemergence (PRE) application of clomazone at 0.36 kg ha{sup -}1 and oxadiazon at 0.5 kg ha{sup -}1. PRE application of pendimethalin at 1.32 kg ha{sup -}1 combined with clomazone at 0.36 kg ha{sup -}1 decreased rice yield. Postemergence (POST) application of bentazon at 1.6 kg ha{sup -}1 + MCPA at 0.25 kg ha{sup -}1 did not injure rice but POST application of azimsulfuron at 0.025 kg ha{sup -}1 produced visual crop injury. Only treatments that controlled grassy weeds since rice was planted and by more than 80% at harvest time lead to acceptable rice yield (> 5,000 kg ha{sup -}1). Clomazone applied PRE at 0.36 kg ha{sup -}1 provided good control of grassy weeds (> 80%) and the highest rice yield, so it is recommended as a selective and efficacious PRE treatment for weed control of annual weeds in sprinkler irrigated rice. The perennial purple nutsedge was difficult to control at high plant densities (> 150 plants m{sup -}2) and the recommended herbicide is azimsulfuron applied at POST at 0.02 kg ha{sup -}1. (Author) 37 refs.

  17. Eradication of Major Weeds

    Science.gov (United States)

    Indian Journal of Adult Education, 1975

    1975-01-01

    Strategies for weed control in cropped and non-cropped areas are presented together with an operational plan for implementing a program for weed control at the national level. The program includes training personnel and community education procedures. (EC)

  18. Eradication of Major Weeds

    Science.gov (United States)

    Indian Journal of Adult Education, 1975

    1975-01-01

    Strategies for weed control in cropped and non-cropped areas are presented together with an operational plan for implementing a program for weed control at the national level. The program includes training personnel and community education procedures. (EC)

  19. Research on the weed control degree and glyphosate soil biodegradation in apple plantations (Pioneer variety

    Directory of Open Access Journals (Sweden)

    Ersilia ALEXA

    2010-05-01

    Full Text Available In this study we follow control degree of glyphosate herbicide on weeds in apple plantations (Pioneer variety of the Research Station Timisoara. It was also followed glyphosate biodegradation capacity in the soil by determining the amount of CO2 released by the action of microorganisms on C14 glyphosate marked isotope. Laboratory analysis of glyphosate residues in soil was made using a Liquid Scintillation TRIATHLER. Glyphosate biodegradation ability in the presence of soil microorganisms is high, so glyphosate residues remaining in soil, in terms of its use in weed combating, are minimal. Study of glyphosate biodegradation capacity in the experimental field indicates that the CO2 fraction accumulated after 50 days is 28.02% for samples exposed in the experimental field. Weather conditions, especially temperature variations between day and night, influences the activity of soilmicroorganisms and affect biodegraded glyphosate percentage.Chemical method of weed control consisted in: herbicide used was Roundup 3 l/ha (glyphosate isopropyl amine salt 360 g/l and are based on chemical application on weeds, on the rows of trees, on their uptake and translocation in their organs having as principal scope the total destruction of weeds. The experimental results obtained reveal a weed combat degree of 82.98% , in the case of chemical variant, compared with control variant. The species combated mainly due to glyphosate herbicide, which is no longer found in the final mapping are: Capsella bursa-pastoris, Chenopodium album, Echinochloa crus-galli, Plantago major, Polygonum aviculare. Total combated weeds /m2 with glyphosate is 126.67.

  20. Effect of chemical and mechanical weed control on cassava yield, soil quality and erosion under cassava cropping system

    Science.gov (United States)

    Islami, Titiek; Wisnubroto, Erwin; Utomo, Wani

    2016-04-01

    Three years field experiments were conducted to study the effect of chemical and mechanical weed control on soil quality and erosion under cassava cropping system. The experiment were conducted at University Brawijaya field experimental station, Jatikerto, Malang, Indonesia. The experiments were carried out from 2011 - 2014. The treatments consist of three cropping system (cassava mono culture; cassava + maize intercropping and cassava + peanut intercropping), and two weed control method (chemical and mechanical methods). The experimental result showed that the yield of cassava first year and second year did not influenced by weed control method and cropping system. However, the third year yield of cassava was influence by weed control method and cropping system. The cassava yield planted in cassava + maize intercropping system with chemical weed control methods was only 24 t/ha, which lower compared to other treatments, even with that of the same cropping system used mechanical weed control. The highest cassava yield in third year was obtained by cassava + peanuts cropping system with mechanical weed control method. After three years experiment, the soil of cassava monoculture system with chemical weed control method possessed the lowest soil organic matter, and soil aggregate stability. During three years of cropping soil erosion in chemical weed control method, especially on cassava monoculture, was higher compared to mechanical weed control method. The soil loss from chemical control method were 40 t/ha, 44 t/ha and 54 t/ha for the first, second and third year crop. The soil loss from mechanical weed control method for the same years was: 36 t/ha, 36 t/ha and 38 t/ha. Key words: herbicide, intercropping, soil organic matter, aggregate stability.

  1. Ecologically sustainable weed management

    DEFF Research Database (Denmark)

    Liebman, Matt; Baraibar, Bàrbara; Buckley, Yvonne

    2016-01-01

    will be effective in various locations. Implementing new approaches for weed management will require multidisciplinary teams comprised of scientists, engineers, economists, sociologists, educators, farmers, land managers, industry personnel, policy makers, and others willing to focus on weeds within whole farming......Weed management is a critically important activity on both agricultural and non-agricultural lands, but it is faced with a daunting set of challenges: environmental damage caused by control practices, weed resistance to herbicides, accelerated rates of weed dispersal through global trade......, and greater weed impacts due to changes in climate and land use. Broad-scale use of new approaches is needed if weed management is to be successful in the coming era. We examine three approaches likely to prove useful for addressing current and future challenges from weeds: diversifying weed management...

  2. Are herbicides a once in a century method of weed control?

    Science.gov (United States)

    Davis, Adam S; Frisvold, George B

    2017-11-01

    The efficacy of any pesticide is an exhaustible resource that can be depleted over time. For decades, the dominant paradigm - that weed mobility is low relative to insect pests and pathogens, that there is an ample stream of new weed control technologies in the commercial pipeline, and that technology suppliers have sufficient economic incentives and market power to delay resistance - supported a laissez faire approach to herbicide resistance management. Earlier market data bolstered the belief that private incentives and voluntary actions were sufficient to manage resistance. Yet, there has been a steady growth in resistant weeds, while no new commercial herbicide modes of action (MOAs) have been discovered in 30 years. Industry has introduced new herbicide tolerant crops to increase the applicability of older MOAs. Yet, many weed species are already resistant to these compounds. Recent trends suggest a paradigm shift whereby herbicide resistance may impose greater costs to farmers, the environment, and taxpayers than earlier believed. In developed countries, herbicides have been the dominant method of weed control for half a century. Over the next half-century, will widespread resistance to multiple MOAs render herbicides obsolete for many major cropping systems? We suggest it would be prudent to consider the implications of such a low-probability, but high-cost development. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  3. Weed control changes and genetically modified herbicide tolerant crops in the USA 1996–2012

    Science.gov (United States)

    Brookes, Graham

    2014-01-01

    Crops that have been genetically modified (GM) to be tolerant to herbicides have been widely grown in the USA since 1996. The rapid and widespread adoption of this technology reflects the important economic and environmental benefits that farmers have derived from its use (equal to $21.7 billion additional farm income and a 225 million kg reduction in herbicide active ingredient use 1996–2012). During this time, weed control practices in these crops relative to the ‘conventional alternative’ have evolved to reflect experience of using the technology, the challenges that have arisen and the increasing focus in recent years on developing sustainable production systems. This paper examines the evidence on the changing nature of herbicides used with these crops and in particular how farmers addressed the challenge of weed resistance. The evidence shows that use of the technology has resulted in a net reduction in both the amount of herbicide used and the associated environmental impact, as measured by the EIQ indicator when compared to what can reasonably be expected if the area planted to GM HT crops reverted to conventional production methods. It also facilitated many farmers being able to derive the economic and environmental benefits associated with switching from a plough-based to a no tillage or conservation tillage production system. In terms of herbicide use, the technology has also contributed to a change the profile of herbicides used. A broad range of, mostly selective herbicides has been replaced by one or 2 broad-spectrum herbicides (mostly glyphosate) used in conjunction with one or 2 other (complementary) herbicides. Since the mid-2000s, the average amount of herbicide applied and the associated environmental load, as measured by the EIQ indicator, have increased on both GM HT and conventional crops. A primary reason for these changes has been increasing incidence of weed species developing populations resistant to herbicides and increased

  4. Weed control changes and genetically modified herbicide tolerant crops in the USA 1996-2012.

    Science.gov (United States)

    Brookes, Graham

    2014-01-01

    Crops that have been genetically modified (GM) to be tolerant to herbicides have been widely grown in the USA since 1996. The rapid and widespread adoption of this technology reflects the important economic and environmental benefits that farmers have derived from its use (equal to $21.7 billion additional farm income and a 225 million kg reduction in herbicide active ingredient use 1996-2012). During this time, weed control practices in these crops relative to the 'conventional alternative' have evolved to reflect experience of using the technology, the challenges that have arisen and the increasing focus in recent years on developing sustainable production systems. This paper examines the evidence on the changing nature of herbicides used with these crops and in particular how farmers addressed the challenge of weed resistance. The evidence shows that use of the technology has resulted in a net reduction in both the amount of herbicide used and the associated environmental impact, as measured by the EIQ indicator when compared to what can reasonably be expected if the area planted to GM HT crops reverted to conventional production methods. It also facilitated many farmers being able to derive the economic and environmental benefits associated with switching from a plough-based to a no tillage or conservation tillage production system. In terms of herbicide use, the technology has also contributed to a change the profile of herbicides used. A broad range of, mostly selective herbicides has been replaced by one or 2 broad-spectrum herbicides (mostly glyphosate) used in conjunction with one or 2 other (complementary) herbicides. Since the mid-2000s, the average amount of herbicide applied and the associated environmental load, as measured by the EIQ indicator, have increased on both GM HT and conventional crops. A primary reason for these changes has been increasing incidence of weed species developing populations resistant to herbicides and increased awareness of

  5. What do farmers' weed control decisions imply about glyphosate resistance? Evidence from surveys of US corn fields.

    Science.gov (United States)

    Wechsler, Seth J; McFadden, Jonathan R; Smith, David J

    2017-04-26

    The first case of glyphosate-resistant weeds in the United States was documented in 1998, 2 years after the commercialization of genetically engineered herbicide-resistant (HR) corn and soybeans. Currently, over 15 glyphosate-resistant weed species affect US crop production areas. These weeds have the potential to reduce yields, increase costs, and lower farm profitability. The objective of our study is to develop a behavioral model of farmers' weed management decisions and use it to analyze weed resistance to glyphosate in US corn farms. On average, we find that weed control increased US corn yields by 3700 kg ha(-1) (worth approximately $US 255 ha(-1) ) in 2005 and 3500 kg ha(-1) (worth approximately $US 575 ha(-1) ) in 2010. If glyphosate resistant weeds were absent, glyphosate killed approximately 99% of weeds, on average, when applied at the label rate in HR production systems. Average control was dramatically lower in states where glyphosate resistance was widespread. We find that glyphosate resistance had a significant impact on weed control costs and corn yields of US farmers in 2005 and 2010. Published 2017. This article is a U.S. Government work and is in the public domain in the USA. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  6. CONVISO® SMART – a new solution to control monocotyledonous and dicotyledonous weeds in ALStolerant sugar beets

    Directory of Open Access Journals (Sweden)

    Balgheim, Natalie

    2016-02-01

    Full Text Available CONVISO SMART is a new system to control monocotyledonous and dicotyledonous weeds in ALS-inhibitor tolerant sugar beets. This system consists of an ALS-inhibiting herbicide and a sugar beet variety which is tolerant against the complementary herbicide due to classic breeding mechanisms. The herbicide CONVISO is a combination of the two active ingredients foramsulfuron and thiencarbazonemethyl. Whereas foramsulfuron is the leaf active compound, thiencarbazone-methyl is leaf as well as soil active. The product will be formulated as an oily dispersion (OD. The registration was requested with an application rate of 1 x 1 l/ha or 2 x 0.5 l/ha in ALS-inhibitor tolerant sugar beets. Application should be done from BBCH 10 – 14 of the weeds, especially of Chenopodium album as well as from BBCH 12 – 18 of the sugar beet. The estimated introduction of this system on the German market will be 2018. CONVISO is well active against the most important weeds in sugar beets, including Polygonum and Chenopodium species. Furthermore several difficult to control weeds as Aethusa cynapium and Mercurialis annua will be controlled by CONVISO. The addition of special herbicides to control those difficult weeds will no longer be necessary. The tolerance of the variety against CONVISO is very strong, which will be shown by the results of the weed free selectivity trials. Due to the high tolerance of the variety against CONVISO and the not occurring of negative herbicide effects, the full yield potential can be utilized.

  7. Use of multicopy transposons bearing unfitness genes in weed control: four example scenarios.

    Science.gov (United States)

    Gressel, Jonathan; Levy, Avraham A

    2014-11-01

    We speculate that multicopy transposons, carrying both fitness and unfitness genes, can provide new positive and negative selection options to intractable weed problems. Multicopy transposons rapidly disseminate through populations, appearing in approximately 100% of progeny, unlike nuclear transgenes, which appear in a proportion of segregating populations. Different unfitness transgenes and modes of propagation will be appropriate for different cases: (1) outcrossing Amaranthus spp. (that evolved resistances to major herbicides); (2) Lolium spp., important pasture grasses, yet herbicide-resistant weeds in crops; (3) rice (Oryza sativa), often infested with feral weedy rice, which interbreeds with the crop; and (4) self-compatible sorghum (Sorghum bicolor), which readily crosses with conspecific shattercane and with allotetraploid johnsongrass (Sorghum halepense). The speculated outcome of these scenarios is to generate weed populations that contain the unfitness gene and thus are easily controllable. Unfitness genes can be under chemically or environmentally inducible promoters, activated after gene dissemination, or under constitutive promoters where the gene function is utilized only at special times (e.g. sensitivity to an herbicide). The transposons can be vectored to the weeds by introgression from the crop (in rice, sorghum, and Lolium spp.) or from planted engineered weed (Amaranthus spp.) using a gene conferring the degradation of a no longer widely used herbicide, especially in tandem with an herbicide-resistant gene that kills all nonhybrids, facilitating the rapid dissemination of the multicopy transposons in a weedy population.

  8. Study on different densities of cumin and chickpea intercropping with emphasis on weed control

    Directory of Open Access Journals (Sweden)

    reza abasi ali kamar

    2009-06-01

    Full Text Available In order to study the effect of different densities of intercropping cumin and chickpea, an experiment was conducted in the farm of Agriculture College of Mashhad. This experiment was conducted as a strip design based on RCBD with four replications. Main plots included weed control treatments (I- one time control in growing season on emergence stage. II- without control and subplots included 5 different densities (I- 120 pl/m2 cumin. II- 90 pl/m2 cumin + 15 pl/m2 chickpea. III- 60 pl/m2 cumin + 30 pl/m2 chickpea. IV- 30 pl/m2 cumin + 45 pl/m2 chickpea. V- 60 pl/m2 chickpea.. The results showed a significant difference in all growth indices in all one time weed control and without weed control treatments. As the densities decreased, both crop's growth indices decreased. The decrease of chickpea yield in all densities in both weed control treatments, showed significant difference. Crop growth rate (CGR and leaf area index (LAI in cumin despite of chickea has affected positively by intercropping. Total land equivalent ratio (LER in all treatments was more than one and partial LER only in 90 pl/m2 was more than one that shows the positive effect of intercropping on cumin yield.

  9. Allelopathy--a natural alternative for weed control.

    Science.gov (United States)

    Macías, Francisco A; Molinillo, José M G; Varela, Rosa M; Galindo, Juan C G

    2007-04-01

    Allelopathy studies the interactions among plants, fungi, algae and bacteria with the organisms living in a certain ecosystem, interactions that are mediated by the secondary metabolites produced and exuded into the environment. Consequently, allelopathy is a multidisciplinary science where ecologists, chemists, soil scientists, agronomists, biologists, plant physiologists and molecular biologists offer their skills to give an overall view of the complex interactions occurring in a certain ecosystem. As a result of these studies, applications in weed and pest management are expected in such different fields as development of new agrochemicals, cultural methods, developing of allelopathic crops with increased weed resistance, etc. The present paper will focus on the chemical aspects of allelopathy, pointing out the most recent advances in the chemicals disclosed, their mode of action and their fate in the ecosystem. Also, attention will be paid to achievements in genomics and proteomics, two emerging fields in allelopathy. Rather than being exhaustive, this paper is intended to reflect a critical vision of the current state of allelopathy and to point to future lines of research where in the authors' opinion the main advances and applications could and should be expected.

  10. Foliar Potassium Fertilizer Additives Affect Soybean Response and Weed Control with Glyphosate

    OpenAIRE

    Nelson, Kelly A.; Peter P. Motavalli; Stevens, William E.; Kendig, John A.; David Dunn; Manjula Nathan

    2012-01-01

    Research in 2004 and 2005 determined the effects of foliar-applied K-fertilizer sources (0-0-62-0 (%N-%P2O5-%K2O-%S), 0-0-25-17, 3-18-18-0, and 5-0-20-13) and additive rates (2.2, 8.8, and 17.6 kg K ha−1) on glyphosate-resistant soybean response and weed control. Field experiments were conducted at Novelty and Portageville with high soil test K and weed populations and at Malden with low soil test K and weed populations. At Novelty, grain yield increased with fertilizer additives at 8.8 kg K ...

  11. A new strategy for controlling invasive weeds: selecting valuable native plants to defeat them

    OpenAIRE

    2015-01-01

    To explore replacement control of the invasive weed Ipomoea cairica, we studied the competitive effects of two valuable natives, Pueraria lobata and Paederia scandens, on growth and photosynthetic characteristics of I. cairica, in pot and field experiments. When I. cairica was planted in pots with P. lobata or P. scandens, its total biomass decreased by 68.7% and 45.8%, and its stem length by 33.3% and 34.1%, respectively. The two natives depressed growth of the weed by their strong effects o...

  12. Diversifying cereal-based rotations to improve weed control. Evaluation with the AlomySys model quantifying the effect of cropping systems on a grass weed

    Directory of Open Access Journals (Sweden)

    Colbach Nathalie

    2010-09-01

    Full Text Available Simplified rotations often select weed flora consisting of one or several dominant species. In rotations consisting mainly of winter cereals, one of the most frequent weeds in Atlantic European countries is blackgrass (Alopecurus myosuroides Huds.. In order to reduce environmental impacts and avoid the selection of herbicide-resistant populations, alternative weed management strategies are necessary. The objective of the present study was to develop a methodology for using a weed dynamics model called ALOMYSYS for evaluating prospective diversified crop rotations based on expert opinion. These prospective rotations were developed for a particular region aiming at reducing herbicide use while keeping weed infestation similar to that in current cropping systems. The prospective systems were also evaluated economically by calculating costs and margins for the farmer. The simulations showed that the more diverse the rotation, the better blackgrass was controlled and the less herbicides (rates and frequencies were necessary. Optimal herbicide spraying conditions and mouldboard ploughing were also less essential in diverse rotations. It was though essential to reason herbicide programs over the whole rotation and not simply as function of the preceding crop. The economic evaluation identified the interest of spring or winter pea either replacing or preceding oilseed rape (OSR in OSR/wheat/barley rotations.

  13. Control of aquatic weeds through pollutant reduction and weed utilization: a weed management approach in the lower Kafue River of Zambia

    Science.gov (United States)

    Sinkala, Thomson; Mwase, Enala T.; Mwala, Mick

    The aquatic weed situation in the Kafue River in Zambia continues to be a major challenge to the sustainable utilization of the water resources of the river. The general methods for managing the weeds, especially the water hyacinth, include use of bio-agents, chemicals, mechanical and physical approaches. These have had very little impact. This paper reports on a project that is investigating weed management strategies which involve use of cleaner production (CP) approach and the utilization of the weed for economic purposes. In addition, the ecological implications of these methods are being assessed. Effluent assessments indicated that apart from nitrates and phosphates, other effluent parameters met the Environmental Council of Zambia standards. Results further show that all the 24 areas surveyed for CP have uncontrolled socio-economic activities which generate both point and non-point sources of pollution that enter the water bodies. To minimize pollution, efforts include devising policy and technical strategies with the involvement of the affected riparian community. Production of mushroom by the communities using the water hyacinth substrate has been demonstrated. Up to 2.1 kg of mushroom was harvested from a single flush over a period of 4-5 weeks. Vegetables grown on soils treated with water hyacinth manure performed better than those grown using commercial fertiliser. The economics of the production are however, yet to be confirmed. If weed usage is proven economically and ecologically viable, the riverine community is envisaged to play a big role in aquatic weed management. High numbers of invertebrates known to be sensitive to pollution have been recorded in the weed-infested Kafue River implying that the water is of “good” quality for these aquatic invertebrates. This observed quality of water may be due to water hyacinth playing a role by sieving pollutants from the river.

  14. Ecologically sustainable weed management

    NARCIS (Netherlands)

    Liebman, Matt; Baraibar, Bàrbara; Buckley, Yvonne; Childs, Dylan; Christensen, Svend; Cousens, Roger; Eizenberg, Hanan; Heijting, Sanne; Loddo, Donato; Merotto, Aldo; Renton, Michael; Riemens, Marleen

    2016-01-01

    Weed management is a critically important activity on both agricultural and non-agricultural lands, but it is faced with a daunting set of challenges: environmental damage caused by control practices, weed resistance to herbicides, accelerated rates of weed dispersal through global trade, and

  15. Direct control of perennial weeds between crops - Implication for organic farming

    DEFF Research Database (Denmark)

    Melander, Bo; Holst, Niels; Rasmussen, Ilse Ankjær;

    2012-01-01

    Perennial weeds can be a major constraint to organic crop production and direct control actions applied between crops can then be necessary to reduce the problems. We conducted two experiments, one on a sandy loam and one on a sandy soil in Denmark, with the aim of studying the efficacy of differ......Perennial weeds can be a major constraint to organic crop production and direct control actions applied between crops can then be necessary to reduce the problems. We conducted two experiments, one on a sandy loam and one on a sandy soil in Denmark, with the aim of studying the efficacy......, power take-off driven implements with rotating weeding devices demonstrated similar control efficacies against a mixed stand composing C. arvense, Tussilago farfara, Elytrigia repens and Artemisia vulgaris. One pass was conducted a week after barley harvest followed by another pass 3 weeks later...... and ending the strategy with mouldboard ploughing in the succeeding spring. Grain yields did not differ among the treatments in the two experiments as a result of the generally high effectiveness exerted by the control strategies. Especially post-harvest control strategies based on rotating weed devices...

  16. Direct control of perennial weeds between crops - Implication for organic farming

    DEFF Research Database (Denmark)

    Melander, Bo; Holst, Niels; Rasmussen, Ilse Ankjær

    2012-01-01

    Perennial weeds can be a major constraint to organic crop production and direct control actions applied between crops can then be necessary to reduce the problems. We conducted two experiments, one on a sandy loam and one on a sandy soil in Denmark, with the aim of studying the efficacy of differ......Perennial weeds can be a major constraint to organic crop production and direct control actions applied between crops can then be necessary to reduce the problems. We conducted two experiments, one on a sandy loam and one on a sandy soil in Denmark, with the aim of studying the efficacy......, power take-off driven implements with rotating weeding devices demonstrated similar control efficacies against a mixed stand composing C. arvense, Tussilago farfara, Elytrigia repens and Artemisia vulgaris. One pass was conducted a week after barley harvest followed by another pass 3 weeks later...... and ending the strategy with mouldboard ploughing in the succeeding spring. Grain yields did not differ among the treatments in the two experiments as a result of the generally high effectiveness exerted by the control strategies. Especially post-harvest control strategies based on rotating weed devices...

  17. Chemical Control of Curled Dock (Rumex crispus L. and Other Weeds in Noncropped Areas

    Directory of Open Access Journals (Sweden)

    Tsvetanka Dimitrova

    2008-01-01

    Full Text Available Rumex crispus L. is an invasive species widespread in our country and in particular in the region of North Bulgaria. It is characterized by high biological and ecological plasticity. Owing to its great reproductive potential, the weed has been assigned to the list of economically most important weeds in the country. With the purpose of studying the possibility of chemical weed control in noncropped areas with heavy natural background infestation with R. crispus L. and other dicotyledonous weeds, two field trials were carried out. A ready-to-use herbicide mixture 2,4-D 140.2 g/l-1 + Triclopyr 144 g/l-1, trade product Genoxon 3X (X0050, was tested at two doses of active ingredient, 3552 and 2842 ml/ha-1. It was found that: (1 population density of Rumex crispus L. can be successfully reduced by treatment at the stage of early stem formation; herbicideefficacy with 3552 and 2882 ml/ha-1 doses on the 21st day after treatment was 100% and 90.5%, respectively, at the end of vegetation 94.4 and 85.7%, respectively; (2 herbicidal efficacy was lower when R. crispus L. was treated at the 5 - 6 leaf stage, being 100 – 94.1%and 80 – 76.5% respectively for the indicated doses and time of recording; (3 at the studied doses the herbicide controlled both annual dicotyledonous weeds (Amaranthus spp., Chenopodium album L., Portulaca oleracea L. and perennial dicotyledonous ones (Cirsiumarvense L., Sonchus arvensis L., Convolvulus arvensis L., Carduus acanthoides L., but it was not toxic to monocotyledonous weeds.

  18. Allelopathic cover crop of rye for integrated weed control in sustainable agroecosystems

    Directory of Open Access Journals (Sweden)

    Vincenzo Tabaglio

    2013-02-01

    Full Text Available The allelopathic potential of rye (Secale cereale L. is mainly due to phytotoxic benzoxazinones, compounds that are produced and accumulated in young tissues to different degrees depending on cultivar and environmental influences. Living rye plants exude low levels of benzoxazinones, while cover crop residues can release from 12 to 20 kg ha–1. This paper summarizes the results obtained from several experiments performed in both controlled and field environments, in which rye was used as a cover crop to control summer weeds in a following maize crop. Significant differences in benzoxazinoid content were detected between rye cultivars. In controlled environments, rye mulches significantly reduced germination of some broadleaf weeds. Germination and seedling growth of Amaranthus retroflexus and Portulaca oleracea were particularly affected by the application of rye mulches, while Chenopodium album was hardly influenced and Abutilon theophrasti was advantaged by the presence of the mulch. With reference to the influence of agronomic factors on the production of benzoxazinoids, nitrogen fertilization increased the content of allelochemicals, although proportionally less than dry matter. The field trial established on no-till maize confirmed the significant weed suppressiveness of rye mulch, both for grass and broadleaf weeds. A significant positive interaction between nitrogen (N fertilization and notillage resulting in the suppression of broadleaf weeds was observed. The different behavior of the weeds in the presence of allelochemicals was explained in terms of differential uptake and translocation capabilities. The four summer weeds tested were able to grow in the presence of low amounts of benzoxazolin-2(3H-one (BOA, between 0.3 and 20 mmol g–1 fresh weight. Although there were considerable differences in their sensitivity to higher BOA concentrations, P. oleracea, A. retroflexus, and Ch. album represented a group of species with a consistent

  19. Effect of reduced doses of mesosulfuron + iodosulfuron to control weeds in no-till wheat under Mediterranean conditions

    Energy Technology Data Exchange (ETDEWEB)

    Barros, J. F. C.; Basch, G.; Freixial, R.; Carvalho, M.

    2009-07-01

    Field experiments were carried out over three years (2004-05, to 2006-07) to study the efficacy of a post-emergence dual-purpose herbicide (mesosulfuron - methyl (3%) + iodosulfuron - methyl - sodium (0.6%) + mefenpyr - diethyl (9%) to control Lolium rigidum Gaud. and broad-leaved weeds in no-till wheat (Triticum aestivum L.). A ready herbicide mixture was used at three doses (6+1.2, 9+1.8 and 12+2.4 g a.i. ha{sup 1}) on two dates (beginning of tillering for L. rigidum and 2-3 pair of leaves for broad-leaved weeds, and complete tillering for L. rigidum and 5-6 pair of leaves for broad-leaved weeds) with three different application volumes (100, 200 and 300 L ha{sup -}1). The results of the present study reveal that using lower than the recommended dose (12+2.4 g ha{sup -}1), the herbicide mixture controls L. rigidum better than it controls some broad-leaved weeds. Effective weed control, which was achieved mainly through the application at the first weed development stage, provided higher grain yields. The lower control efficacy of more developed L. rigidum and broad-leaved weeds and a longer period of competition between crop and weeds are responsible for the significantly lower crop yields for the delayed application. Within each application timing significant differences were obtained among the dose/volume combinations, with the exception of the first application regarding L. rigidum control, indicating that a reduction in herbicide dose is possible, but only for certain dose/volume combinations. Nonetheless, weed control was maintained across an array of dose/volume combinations, especially with L. rigidum, thus, our results demonstrate that reduced doses can effectively control weeds if applied early. (Author) 31 refs.

  20. Row Spacing Determines Critical Period of Weed Control in Crop: Cowpea (Vigna unguiculata as a Case Study

    Directory of Open Access Journals (Sweden)

    Omobolanle Adewale Osipitan

    2016-10-01

    Full Text Available To further understand the importance of row spacing as an agronomic practice, a study was conducted to evaluate how levels of row spacing determines the critical period of weed control (CPWC in cowpea (Vigna unguiculata. The experiment was laid out as a split-plot design with eight periods of weed interference as the main plots and three row spacing (60, 75 90 cm as the subplots with three replications of each treatment combination. Period of weed interference consisted of weed removal for 14, 35, 54, and 77 days after emergence (DAE, and weed infestation for 14, 35, 54, and 77 DAE. Results indicated that the mean yield of cowpea was higher at narrow spacing (60 cm than at wide spacing (90 cm under season-long weed infestation plots but no difference in yield was found among the row spacing in the season-long weed removal plots. There was no difference in the beginning of the CPWC among the row spacing. However, 90 cm row spacing requires longer period of weed removal to avoid unacceptable yield loss when compared to 60 cm row spacing. The end of the CPWC coincides with the period of canopy closure by the crop. This finding suggests that it took the crop longer time to close canopy at wide row spacing (90 cm compare to reduced row spacing. The differences in the duration of weed control intervention in crop row spacing suggest the importance of integrating decisions regarding row spacing and period of weed control in weed management strategies.

  1. A sterile-female technique proposed for control of Striga hermonthica and other intractable weeds: Advantages, shortcomings, and risk management

    Science.gov (United States)

    Weeds have posed intractable challenges to farmers since the dawn of agriculture. This article describes in detail a proposed control strategy based on the introduction of genes conferring female-sterility into the genomes of intractable target weeds. Spread of these genes through target populations...

  2. Split-season herbaceous weed control for full-season seedling performance

    Science.gov (United States)

    Jimmie L. Yeiser; Andrew W. Ezell

    2010-01-01

    Results from four loblolly pine (Pinus taeda L.) sites, one in each of MS and TX in 2001 and again in 2002, are presented. Twelve herbicide treatments and an untreated check were tested. Herbicide treatments were applied early (mid-March), late (mid-May), both timings, or not at all to achieve, early- late-, full-season, or no weed control. When...

  3. The issues of weed infestation with environmentally hazardous plants and methods of their control

    Science.gov (United States)

    Bogdanov, V. L.; Posternak, T. S.; Pasko, O. A.; Kovyazin, V. F.

    2016-09-01

    The authors analyze expansion of segetal and ruderal vegetation on agricultural lands in Leningrad and Tomsk oblasts, typical for the European and Asian parts of Russia. The spreading conditions, composition of species, biological features and ecological requirements of the most aggressive species are identified. Some effective ways of weed control are suggested.

  4. Evaluating subsoiling and herbaceous weed control on shortleaf pine planted in retired farm land

    Science.gov (United States)

    John D. Kushla

    2010-01-01

    In March 2005, shortleaf pine was planted on retired fields of the Mississippi Agriculture and Forestry Experiment Station in Holly Springs. The objectives were to evaluate subsoiling and herbaceous weed control on first year seedling stocking, survival, and size. First year seedling measurements were made on stocking, survival, and size. Only results for first year...

  5. Automatic Weed Control System For Transplanted Processing Tomatoes Using X-ray Stem Sensing

    Science.gov (United States)

    A stem detection system was developed for automatic weed control in transplanted tomato fields. A portable x-ray source projected an x-ray beam perpendicular to the crop row and parallel to the soil surface. The plant’s main stem absorbs x-ray energy, decreasing the detected signal and allowing ste...

  6. Diapause in Abrostola asclepiadis (Lepidoptera: Noctuidae) may make for an ineffective weed biological control agent

    Science.gov (United States)

    Pale and black swallow-wort (Vincetoxicum rossicum and V. nigrum; Apocynaceae, subfamily Asclepiadoideae) are perennial vines from Europe that are invasive in various terrestrial habitats in the northeastern USA and southeastern Canada. A classical weed biological control program has been in develop...

  7. Potential Use of Abrasive Air-Propelled Agricultural Residues for Weed Control

    Science.gov (United States)

    A new postemergence weed control tactic is proposed for organic production systems that results in plant abrasion and death upon assault from abrasive grits propelled by compressed air. Grit derived from granulated walnut shells was delivered by a sand blaster at 517 kPa at distances of 30 to 60 cm ...

  8. Ten-Year Growth of Five Planted Hardwood Species Mechanical Weed Control on Sharkey Clay Soil

    Science.gov (United States)

    Roger M. Krinard; Harvey E. Kennedy

    1983-01-01

    Five hardwood species planted on Sharkey clay soil showed little practical difference in growth whether plots were mowed or diskedfor weed control in years 6 to 10, although disking had given better growth in the first 5 years. After 10 years, cottonwood (Populus deltoides Bartr. ex Marsh.) stem volume was at least three times greater than other species. Changes in...

  9. Status of biological control projects on terrestrial invasive alien weeds in California

    Science.gov (United States)

    In cooperation with foreign scientists, we are currently developing new classical biological control agents for five species of invasive alien terrestrial weeds. Cape-Ivy. A gall-forming fly, Parafreutreta regalis, and a stem-boring moth, Digitivalva delaireae, have been favorably reviewed by TAG...

  10. Impact of weed control on arbuscular mycorrhizal fungi in a tropical agroecosystem: a long-term experiment.

    Science.gov (United States)

    Ramos-Zapata, José A; Marrufo-Zapata, Denis; Guadarrama, Patricia; Carrillo-Sánchez, Lilia; Hernández-Cuevas, Laura; Caamal-Maldonado, Arturo

    2012-11-01

    Cover crop species represent an affordable and effective weed control method in agroecosystems; nonetheless, the effect of its use on arbuscular mycorrhizal fungi (AMF) has been scantily studied. The goal of this study was to determine root colonization levels and AMF species richness in the rhizosphere of maize plants and weed species growing under different cover crop and weed control regimes in a long-term experiment. The treatment levels used were (1) cover of Mucuna deeringian (Muc), (2) "mulch" of Leucaena leucocephala (Leu), (3) "mulch" of Lysiloma latisiliquum (Lys), (4) herbicide (Her), (5) manual weeding (CD), (6) no weeding (SD), and (7) no maize and no weeding (B). A total of 18 species of AMF belonging to eight genera (Acaulospora, Ambispora, Claroideoglomus, Funneliformis, Glomus, Rhizophagus, Sclerocystis, and Scutellospora) were identified from trap cultures. Muc and Lys treatments had a positive impact on AMF species richness (11 and seven species, respectively), while Leu and B treatments on the other hand gave the lowest richness values (six species each). AMF colonization levels in roots of maize and weeds differed significantly between treatment levels. Overall, the use of cover crop species had a positive impact on AMF species richness as well as on the percentage of root colonized by AMF. These findings have important implications for the management of traditional agroecosystems and show that the use of cover crop species for weed control can result in a more diverse AMF community which should potentially increase crop production in the long run.

  11. Use of Essential Oils of Cinnamon, Lavender and Peppermint for Weed Control

    Directory of Open Access Journals (Sweden)

    Fabio Caporali

    2007-06-01

    Full Text Available The indiscriminate use of synthetic chemical compounds for weed control has been often responsible of damage to both the environment and the human health. To challenge these problems, in the last years research has increased its effort to find out alternative farming strategies. A feasible alternative could be the identification of natural substances with allelopathic effects for the realization of natural herbicides. Some research has already highlighted the possibility of using essential oils, extracted from aromatic plants, for weed control. The advantage in the utilization of such natural compounds is the quickly breaking down process into the environment and so the possible application in sustainable agriculture like organic farming. Objective of this research was the evaluation of the inhibition effect exerted by the essential oils of cinnamon, peppermint and lavender on seeds germination of some of the most common weeds species of the Mediterranean environment (pigweed, wild mustard and ryegrass. The results have highlighted a control in the weeds germination. Among the essential oils tested, cinnamon oil has exerted the highest inhibition effect compared with lavender and peppermint ones. The dicotyledonous species have been more susceptible compared with the monocotyledonous, even if it has been recorded only for redroot pigweed a dose able to inhibit totally the seed germination.

  12. Organic weed conrol and cover crop residue integration impacts on weed control, quality, and yield and economics in conservation tillage tomato - A case study

    Science.gov (United States)

    The increased use of conservation tillage in vegetable production requires more information be developed on the role of cover crops in weed control, tomato quality and yield. Three conservation-tillage systems utilizing crimson clover, brassica and cereal rye as winter cover crops were compared to ...

  13. Humic substances and its distribution in coffee crop under cover crops and weed control methods

    Directory of Open Access Journals (Sweden)

    Bruno Henrique Martins

    2016-08-01

    Full Text Available ABSTRACT Humic substances (HS comprise the passive element in soil organic matter (SOM, and represent one of the soil carbon pools which may be altered by different cover crops and weed control methods. This study aimed to assess HS distribution and characteristics in an experimental coffee crop area subjected to cover crops and cultural, mechanical, and chemical weed control. The study was carried out at Londrina, in the state of Paraná, southern Brazil (23°21’30” S; 51°10’17” W. In 2008, seven weed control/cover crops were established in a randomized block design between two coffee rows as the main-plot factor per plot and soil sampling depths (0-10 cm, 10-20 cm, 20-30 cm and 30-40 cm as a split-plot. HS were extracted through alkaline and acid solutions and analyzed by chromic acid wet oxidation and UV-Vis spectroscopy. Chemical attributes presented variations in the topsoil between the field conditions analyzed. Cover crop cutting and coffee tree pruning residues left on the soil surface may have interfered in nutrient cycling and the humification process. Data showed that humic substances comprised about 50 % of SOM. Although different cover crops and weed control methods did not alter humic and fulvic acid carbon content, a possible incidence of condensed aromatic structures at depth increments in fulvic acids was observed, leading to an average decrease of 53 % in the E4/E6 ratio. Humin carbon content increased 25 % in the topsoil, particularly under crop weed-control methods, probably due to high incorporation of recalcitrant structures from coffee tree pruning residues and cover crops.

  14. A new strategy for controlling invasive weeds: selecting valuable native plants to defeat them

    Science.gov (United States)

    Li, Weihua; Luo, Jianning; Tian, Xingshan; Soon Chow, Wah; Sun, Zhongyu; Zhang, Taijie; Peng, Shaolin; Peng, Changlian

    2015-06-01

    To explore replacement control of the invasive weed Ipomoea cairica, we studied the competitive effects of two valuable natives, Pueraria lobata and Paederia scandens, on growth and photosynthetic characteristics of I. cairica, in pot and field experiments. When I. cairica was planted in pots with P. lobata or P. scandens, its total biomass decreased by 68.7% and 45.8%, and its stem length by 33.3% and 34.1%, respectively. The two natives depressed growth of the weed by their strong effects on its photosynthetic characteristics, including suppression of leaf biomass and the abundance of the CO2-fixing enzyme RUBISCO. The field experiment demonstrated that sowing seeds of P. lobata or P. scandens in plots where the weed had been largely cleared produced 11.8-fold or 2.5-fold as much leaf biomass of the two natives, respectively, as the weed. Replacement control by valuable native species is potentially a feasible and sustainable means of suppressing I. cairica.

  15. Integrated control of annual weeds by inter-row hoeing and intra-row herbicide treatment in spring oilseed rape

    Directory of Open Access Journals (Sweden)

    Nilsson, Anders

    2014-02-01

    Full Text Available The aim of this project is to develop an integrated weed control strategy against annual weeds in spring oilseed rape by means of a combined mechanical and chemical weed control which will be performed concurrently and separately. The project encompasses field experiments in which different combinations of inter-row hoeing and intra-row herbicide treatments will be evaluated and compared to conventional weed control treatments with broadcast spraying of herbicides, and experiments in which an implement for concurrent inter-row hoeing and intra-row herbicide treatment will be refined and evaluated. In 2012, an implement for intra-row spraying combined with row hoeing was developed and evaluated in two field experiments in spring oilseed rape in the southern part of Sweden. The effects of inter-row hoeing, intra row spraying, and combination of the two methods were compared with conventional broadcast spraying. Preliminary results showed that the best weed control effects were obtained with the combination of inter-row hoeing and intra-row spraying in both experiments. Regarding crop yield, the yield was significantly higher in the combined treatment in one of the experiments while no effects on the yields were obtained in the other experiment. We envisage that the inter-row hoeing and intra-row herbicide treatment will diminish the overall use of herbicides to less than one third in comparison with the more conventional chemical weed control methods, while having the same weed control effect.

  16. Strip Tillage and Early-Season Broadleaf Weed Control in Seeded Onion (Allium cepa

    Directory of Open Access Journals (Sweden)

    Sarah Gegner-Kazmierczak

    2016-03-01

    Full Text Available Field experiments were conducted in 2007 and 2008 near Oakes, North Dakota (ND, USA, to evaluate if strip tillage could be incorporated into a production system of seeded onion (Allium cepa to eliminate the standard use of a barley (Hordeum vulgare companion crop with conventional, full width tillage, yet support common early-season weed control programs. A split-factor design was used with tillage (conventional and strip tillage as the main plot and herbicide treatments (bromoxynil, DCPA, oxyfluorfen, and pendimethalin as sub-plots. Neither tillage nor herbicide treatments affected onion stand counts. Common lambsquarters (Chenopodium album densities were lower in strip tillage compared to conventional tillage up to three weeks after the post-emergence applied herbicides. In general, micro-rate post-emergence herbicide treatments provided greater early-season broadleaf weed control than pre-emergence herbicide treatments. Onion yield and grade did not differ among herbicide treatments because the mid-season herbicide application provided sufficient control/suppression of the early-season weed escapes that these initial weed escapes did not impact onion yield or bulb diameter. In 2007, onion in the strip tillage treatment were larger in diameter resulting in greater total and marketable yields compared to conventional tillage. Marketable onion yield was 82.1 Mg ha−1 in strip tillage and 64.9 Mg ha−1 in conventional tillage. Results indicate that strip tillage use in direct-seeded onion production was beneficial, especially when growing conditions were conducive to higher yields and that the use of strip tillage in onion may provide an alternative to using a companion crop as it did not interfere with either early-season weed management system.

  17. Effect of tillage on the efficacy of CGA362622 on weed control in maize

    African Journals Online (AJOL)

    STORAGESEVER

    2008-12-03

    Dec 3, 2008 ... help in managing herbicide resistance weeds and may also increase weed density as well as reduce crop yield. (Anderson, 2004). Higher dose of .... This change in weed compo- sition agrees with Richley et al. (1977) ...

  18. Water retention and s index of an oxisol subjected to weed control methods in a coffee crop

    Directory of Open Access Journals (Sweden)

    Raphael Henrique da Silva Siqueira

    2014-10-01

    Full Text Available Weed control in different crops affects the chemical, physical, and biological properties of the soil and consequently its structural quality. The objective of this study was to evaluate, using water retention characteristics and the S index, the physical quality of an Oxisol (Red-Yellow Latosol, subjected to weed control during the cultivation of coffee. The following weed control methods were evaluated: harrowing, brushcutting, residue crushing, manual weeding, post-emergence herbicide application, pre-emergence herbicide application, and maintenance of soil cover with peanut forage, Brachiaria grass, and spontaneous vegetation (no weed treatment. The following properties were determined for physical characterization of the soil: bulk density, total porosity, macroporosity, microporosity, water retention, and the S index. The weed control method significantly affected the physical properties and water retention in the subsurface layer of the Oxisol. Soil bulk density, total porosity, macroporosity, and microporosity were significantly correlated with the S index. According to the S index, the physical quality of the soil was classified as very good for the various weed control methods investigated.

  19. Foliar Potassium Fertilizer Additives Affect Soybean Response and Weed Control with Glyphosate

    Directory of Open Access Journals (Sweden)

    Kelly A. Nelson

    2012-01-01

    Full Text Available Research in 2004 and 2005 determined the effects of foliar-applied K-fertilizer sources (0-0-62-0 (%N-%P2O5-%K2O-%S, 0-0-25-17, 3-18-18-0, and 5-0-20-13 and additive rates (2.2, 8.8, and 17.6 kg K ha−1 on glyphosate-resistant soybean response and weed control. Field experiments were conducted at Novelty and Portageville with high soil test K and weed populations and at Malden with low soil test K and weed populations. At Novelty, grain yield increased with fertilizer additives at 8.8 kg K ha−1 in a high-yield, weed-free environment in 2004, but fertilizer additives reduced yield up to 470 kg ha−1 in a low-yield year (2005 depending on the K source and rate. At Portageville, K-fertilizer additives increased grain yield from 700 to 1160 kg ha−1 compared to diammonium sulfate, depending on the K source and rate. At Malden, there was no yield response to K sources. Differences in leaf tissue K (P=0.03, S (P=0.03, B (P=0.0001, and Cu (P=0.008 concentrations among treatments were detected 14 d after treatment at Novelty and Malden. Tank mixtures of K-fertilizer additives with glyphosate may provide an option for foliar K applications.

  20. Optimization of foramsulfuron doses for post-emergence weed control in maize (Zea mays L.)

    Energy Technology Data Exchange (ETDEWEB)

    Pannacci, E.

    2016-11-01

    Four field experiments were carried out from 2011 to 2014 in order to evaluate the effects of foramsulfuron, applied at the recommended (60.8 g a.i./ha) and reduced doses (1/3 and 2/3), on the efficacy against several of the most important weeds in maize. For each “year-weed” combination, dose-response curves were applied to estimate the dose of foramsulfuron required to obtain 90% and 95% weed control (ED90 and ED95). Foramsulfuron phytotoxicity on maize and crop yield were assessed. Foramsulfuron at 1/3 of the recommended dose (20.3 g a.i./ha) provided 95% efficacy against redroot pigweed (Amaranthus retroflexus L.), green foxtail (Setaria viridis (L.) Beauv.), wild mustard (Sinapis arvensis L.) and black nightshade (Solanum nigrum L.). Velvetleaf (Abutilon theophrasti Medik.), common lambsquarters (Chenopodium album L.) and barnyardgrass (Echinochloa crus-galli (L.) Beauv.) were satisfactorily controlled (95% weed efficacy) with ED95 ranged from 20 to 50 g/ha of foramsulfuron (about from 1/3 to 5/6 of the recommended dose) depending on growth stage. The recommended dose was effective against pale smartweed (Polygonum lapathifolium L.) at 2-4 true leaves (12-14 BBCH scale), but this dose did not kill plants larger than 2-4 true leaves. The ranking among weed species based on their susceptibility to foramsulfuron was: redroot pigweed = green foxtail = wild mustard = black nightshade > velvetleaf = common lambsquarters = barnyardgrass > pale smartweed. Dose of foramsulfuron can be reduced below recommended dose depending on weed species and growth stage. Foramsulfuron showed a good crop selectivity and had no negative effect on maize yield. (Author)

  1. Optimization of foramsulfuron doses for post-emergence weed control in maize (Zea mays L.

    Directory of Open Access Journals (Sweden)

    Euro Pannacci

    2016-08-01

    Full Text Available Four field experiments were carried out from 2011 to 2014 in order to evaluate the effects of foramsulfuron, applied at the recommended (60.8 g a.i./ha and reduced doses (1/3 and 2/3, on the efficacy against several of the most important weeds in maize. For each “year-weed” combination, dose-response curves were applied to estimate the dose of foramsulfuron required to obtain 90% and 95% weed control (ED90 and ED95. Foramsulfuron phytotoxicity on maize and crop yield were assessed. Foramsulfuron at 1/3 of the recommended dose (20.3 g a.i./ha provided 95% efficacy against redroot pigweed (Amaranthus retroflexus L., green foxtail (Setaria viridis (L. Beauv., wild mustard (Sinapis arvensis L. and black nightshade (Solanum nigrum L.. Velvetleaf (Abutilon theophrasti Medik., common lambsquarters (Chenopodium album L. and barnyardgrass (Echinochloa crus-galli (L. Beauv. were satisfactorily controlled (95% weed efficacy with ED95 ranged from 20 to 50 g/ha of foramsulfuron (about from 1/3 to 5/6 of the recommended dose depending on growth stage. The recommended dose was effective against pale smartweed (Polygonum lapathifolium L. at 2-4 true leaves (12-14 BBCH scale, but this dose did not kill plants larger than 2-4 true leaves. The ranking among weed species based on their susceptibility to foramsulfuron was: redroot pigweed = green foxtail = wild mustard = black nightshade > velvetleaf = common lambsquarters = barnyardgrass > pale smartweed. Dose of foramsulfuron can be reduced below recommended dose depending on weed species and growth stage. Foramsulfuron showed a good crop selectivity and had no negative effect on maize yield.

  2. Long-term benefits to the growth of ponderosa pines from controlling southwestern pine tip moth (Lepidoptera: Tortricidae) and weeds.

    Science.gov (United States)

    Wagner, Michael R; Chen, Zhong

    2004-12-01

    The southwestern pine tip moth, Rhyacionia neomexicana (Dyar) (Lepidoptera: Tortricidae), is a native forest pest that attacks seedlings and saplings of ponderosa pine, Pinus ponderosa Dougl. ex Laws, in the southwestern United States. Repeated attacks can cause severe deformation of host trees and significant long-term growth loss. Alternatively, effective control of R. neomexicana, vegetative competition, or both in young pine plantations may increase survival and growth of trees for many years after treatments are applied. We test the null hypothesis that 4 yr of R. neomexicana and weed control with insecticide, weeding, and insecticide plus weeding would not have any residual effect on survival and growth of trees in ponderosa pine plantation in northern Arizona 14 yr post-treatment, when the trees were 18 yr old. Both insecticide and weeding treatment increased tree growth and reduced the incidence of southwestern pine tip moth damage compared with the control. However, weeding alone also significantly increased tree survival, whereas insecticide alone did not. The insecticide plus weeding treatment had the greatest tree growth and survival, and the lowest rate of tip moth damage. Based on these results, we rejected our null hypothesis and concluded that there were detectable increases in the survival and growth of ponderosa pines 14 yr after treatments applied to control R. neomexicana and weeds.

  3. Critical period of weed control in winter canola (Brassica napus L.) in a semi-arid region.

    Science.gov (United States)

    Aghaalikhani, M; Yaghoobi, S R

    2008-03-01

    In order to determine the critical period of weed control in winter canola (Brassica napus L. cv. Okapi) an experiment was carried out at research field of Tarbiat Modarres University, Tehran, Iran on 2004-2005 growing season. Fourteen experimental treatments which divided into two sets were arranged in Randomized complete blocks design with four replications. In the first set, the crop was kept weed-free from emergence time to two-leaf stage (V2), four-leaf stage (V4), six-leaf stage (V6), eight-leaf stage (V8), early flowering (IF), 50% of silique set (50% SS) and final harvest (H). In the second set, weeds where permitted to grow with the crop until above mentioned stages. In this study critical period of weed control was determined according to evaluate seed bank emerged weed biomass effect on canola grain yield loss using Gompertz and logistic equations. Result showed a critical time of weed control about 25 days after emergence (between four to six-leaf stages) with 5% accepted yield loss. Therefore, weed control in this time could provide the best result and avoid yield loss and damage to agroecosystem.

  4. The biological control of aquatic weeds in South Africa: Current status and future challenges

    Directory of Open Access Journals (Sweden)

    Martin P. Hill

    2017-03-01

    Full Text Available Background: Aquatic ecosystems in South Africa are prone to invasion by several invasive alien aquatic weeds, most notably, Eichhornia crassipes (Mart. Solms-Laub. (Pontederiaceae (water hyacinth; Pistia stratiotes L. (Araceae (water lettuce; Salvinia molesta D.S. Mitch. (Salviniaceae (salvinia; Myriophyllum aquaticum (Vell. Conc. Verd. (parrot’s feather; and Azolla filiculoides Lam. (Azollaceae (red water fern. Objective: We review the biological control programme on waterweeds in South Africa. Results: Our review shows significant reductions in the extent of invasions, and a return on biodiversity and socio-economic benefits through the use of this method. These studies provide justification for the control of widespread and emerging freshwater invasive alien aquatic weeds in South Africa. Conclusions: The long-term management of alien aquatic vegetation relies on the correct implementation of biological control for those species already in the country and the prevention of other species entering South Africa.

  5. Study of different herbicide molecules for the control of durum wheat weed

    Directory of Open Access Journals (Sweden)

    Michele Perniola

    Full Text Available In order to enhance the chances to rotate the herbicide molecules, the effectiveness of a new molecule, pinoxaden, was tested, comparing it with other herbicides used in wheat weed control. The trial was carried out comparing the following herbicide mixtures: 1 no weed control treatment; 2 Tribenuron Methyl (TM; 3 Clodinafop (C; 4 Tribenuron Methyl + Clodinafop (TM+C; 5 Pinoxaden + clodinafop + propargile (PCP; 6 Pinoxaden + clodinafop + propargile + Triasulfuron (PCP+T; 7 Pinoxaden + clodinafop + propargile + absolute Ioxinil and Mecoprop (PCP+IM. The new PCP+T herbicides mixture didn’t differ statistically from the traditional TMC treatment in terms of effectiveness, but the agronomic result of the new mixture was totally satisfactory, even taking into account that the marketing of this mixture is not aimed to compete with other existing herbicides but to widen the chance to rotate active principles in time and space, in order to control the onset of resistance phenomena.

  6. The influence of strip cropping and weed control methods on weed diversity in dent maize (Zea mays L., narrow-leafed lupin (Lupinus angustifolius L. and oats (Avena sativa L.

    Directory of Open Access Journals (Sweden)

    Aleksandra Głowacka

    2014-01-01

    Full Text Available The experiment was conducted in 2008–2010 at the Experimental Station of the Faculty of Agricultural Sciences in Zamość, University of Life Sciences in Lublin. The research design included two factors: I. Method of cultivation – sole cropping and strip cropping (the cultivation of three plants: maize, narrow-leafed lupin and oats, in neighboring strips; II. Weed control method – mechanical and chemical. The subject of this study was weed infestation in maize, narrow-leafed lupin and oats. The greatest diversity of weeds was found in the narrow-leafed lupine crop, while the lowest diversity in maize. The dominant weed species in maize, lupine and oats were Echinochloa crus-galli, Chenopodium album and Galinsoga parviflora which ranged from 34% to 99% of the total number of weeds. Strip cropping clearly reduced the number of weeds per unit area in the narrow-leafed lupin and oat crops as well as the aboveground dry weight of weeds in all plant species. Chemical weed control significantly decreased both the number and weight of weeds in comparison with the mechanical method.

  7. Broomrape Weeds. Underground Mechanisms of Parasitism and Associated Strategies for their Control: A Review.

    Science.gov (United States)

    Fernández-Aparicio, Mónica; Reboud, Xavier; Gibot-Leclerc, Stephanie

    2016-01-01

    Broomrapes are plant-parasitic weeds which constitute one of the most difficult-to-control of all biotic constraints that affect crops in Mediterranean, central and eastern Europe, and Asia. Due to their physical and metabolic overlap with the crop, their underground parasitism, their achlorophyllous nature, and hardly destructible seed bank, broomrape weeds are usually not controlled by management strategies designed for non-parasitic weeds. Instead, broomrapes are in current state of intensification and spread due to lack of broomrape-specific control programs, unconscious introduction to new areas and may be decline of herbicide use and global warming to a lesser degree. We reviewed relevant facts about the biology and physiology of broomrape weeds and the major feasible control strategies. The points of vulnerability of some underground events, key for their parasitism such as crop-induced germination or haustorial development are reviewed as inhibition targets of the broomrape-crop association. Among the reviewed strategies are those aimed (1) to reduce broomrape seed bank viability, such as fumigation, herbigation, solarization and use of broomrape-specific pathogens; (2) diversion strategies to reduce the broomrape ability to timely detect the host such as those based on promotion of suicidal germination, on introduction of allelochemical interference, or on down-regulating host exudation of germination-inducing factors; (3) strategies to inhibit the capacity of the broomrape seedling to penetrate the crop and connect with the vascular system, such as biotic or abiotic inhibition of broomrape radicle growth and crop resistance to broomrape penetration either natural, genetically engineered or elicited by biotic- or abiotic-resistance-inducing agents; and (4) strategies acting once broomrape seedling has bridged its vascular system with that of the host, aimed to impede or to endure the parasitic sink such as those based on the delivery of herbicides via

  8. Broomrape weeds. Underground mechanisms of parasitism and associated strategies for their control: a review.

    Directory of Open Access Journals (Sweden)

    Monica eFernandez-Aparicio

    2016-02-01

    Full Text Available Broomrapes are plant-parasitic weeds which constitute one of the most difficult-to-control of all biotic constraints that affect crops in Mediterranean, central and eastern Europe, and Asia. Due to their physical and metabolic overlap with the crop, their underground parasitism, their achlorophyllous nature, and hardly destructible seed bank, broomrape weeds are usually not controlled by management strategies designed for non-parasitic weeds. Instead, broomrape are in a current state of intensification and spread due to lack of broomrape-specific control programs, unconscious introduction to new areas and may be decline of herbicide use and global warming to a lesser degree. We reviewed relevant facts about the biology and physiology of broomrape weeds and the major feasible control strategies. The points of vulnerability of some underground events, key for their parasitism such as crop-induced germination or haustorial development are reviewed as inhibition targets of the broomrape-crop association. Among the reviewed strategies are those aimed 1 to reduce broomrape seed bank viability, such as fumigation, herbigation, solarization and use of broomrape-specific pathogens; 2 diversion strategies to reduce the broomrape ability to timely detect the host such as those based on promotion of suicidal germination, on introduction of allelochemical interference, or on down-regulating host exudation of germination-inducing factors; 3 strategies to inhibit the capacity of the broomrape seedling to penetrate the crop and connect with the vascular system, such as biotic or abiotic inhibition of broomrape radicle growth, crop resistance to broomrape penetration either natural, genetically engineered or elicited by biotic- or abiotic-resistance-inducing agents and 4 strategies acting once broomrape seedling has bridged its vascular system with that of the host, aimed to impede or to endure the parasitic sink such as those based on the delivery of herbicides

  9. Seed preferences by rodents in the agri?environment and implications for biological weed control

    OpenAIRE

    Fischer, Christina;Türke, Manfred

    2016-01-01

    Summary Post?dispersal seed predation and endozoochorous seed dispersal are two antagonistic processes in relation to plant recruitment, but rely on similar preconditions such as feeding behavior of seed consumers and seed traits. In agricultural landscapes, rodents are considered important seed predators, thereby potentially providing regulating ecosystem services in terms of biological weed control. However, their potential to disperse seeds endozoochorously is largely unknown. We exposed s...

  10. Broomrape Weeds. Underground Mechanisms of Parasitism and Associated Strategies for their Control: A Review

    Science.gov (United States)

    Fernández-Aparicio, Mónica; Reboud, Xavier; Gibot-Leclerc, Stephanie

    2016-01-01

    Broomrapes are plant-parasitic weeds which constitute one of the most difficult-to-control of all biotic constraints that affect crops in Mediterranean, central and eastern Europe, and Asia. Due to their physical and metabolic overlap with the crop, their underground parasitism, their achlorophyllous nature, and hardly destructible seed bank, broomrape weeds are usually not controlled by management strategies designed for non-parasitic weeds. Instead, broomrapes are in current state of intensification and spread due to lack of broomrape-specific control programs, unconscious introduction to new areas and may be decline of herbicide use and global warming to a lesser degree. We reviewed relevant facts about the biology and physiology of broomrape weeds and the major feasible control strategies. The points of vulnerability of some underground events, key for their parasitism such as crop-induced germination or haustorial development are reviewed as inhibition targets of the broomrape-crop association. Among the reviewed strategies are those aimed (1) to reduce broomrape seed bank viability, such as fumigation, herbigation, solarization and use of broomrape-specific pathogens; (2) diversion strategies to reduce the broomrape ability to timely detect the host such as those based on promotion of suicidal germination, on introduction of allelochemical interference, or on down-regulating host exudation of germination-inducing factors; (3) strategies to inhibit the capacity of the broomrape seedling to penetrate the crop and connect with the vascular system, such as biotic or abiotic inhibition of broomrape radicle growth and crop resistance to broomrape penetration either natural, genetically engineered or elicited by biotic- or abiotic-resistance-inducing agents; and (4) strategies acting once broomrape seedling has bridged its vascular system with that of the host, aimed to impede or to endure the parasitic sink such as those based on the delivery of herbicides via

  11. Weed control and yield potential for a promising rice line, STG06L-35-061, selected from crosses between weed-suppressive indicas and commercial long-grain rice

    Science.gov (United States)

    Sustainable weed control is an ongoing challenge in rice production. Indica rice lines such as PI 312777 that can suppress Echinochloa crus-galli and other troublesome C4 grass weeds have been evaluated extensively in Arkansas for more than a decade. In an ongoing breeding/selection program, we are...

  12. Phytotoxic potential of Drimys brasiliensis Miers for use in weed control

    Directory of Open Access Journals (Sweden)

    Simoni Anese

    2015-10-01

    Full Text Available This study aims to evaluate the phytotoxicity potential of leaf and root extracts of Drimys brasiliensis on the germination and seedling growth of Panicum maximum and Euphorbia heterophylla and its influence on metaxylem cell size in the seedling roots of the latter specie. The leaf and root extracts were fractionated by partition chromatography, and the hexane and ethyl acetate fractions obtained from each organ were evaluated at different concentrations for phytotoxic activity in several bioassays. In seedling growth tests, we compared the effects of these fractions with the herbicide oxyfluorfen. The hexane fraction of the root extracts showed a higher inhibitory potential on the germination and growth of weeds and reduced the average size of the metaxylem cells of E. heterophylla roots by more than 50%.The inhibitory effects of the root hexane fraction on seedling growth was similar to the herbicide, indicating that D. brasiliensis is a possible alternative form of control for the weed species examined.

  13. Control of an Autonomous Vehicle for Registration of Weed and Crop in Precision Agriculture

    DEFF Research Database (Denmark)

    Nielsen, Kirsten Mølgaard; Andersen, Palle; Pedersen, Tom Søndergaard

    2002-01-01

    The paper describes the development of an autonomous electrical vehicle to be used for weed mapping in precision agriculture with special focus on the conceptual framework of the control system. The lowest layer of the control system is the propulsion and steering control, the second layer...... coordinates the movements of the wheel units, the third layer is path execution and perception and the upper layer performs planning and reasoning. The control system is implemented on an autonomous vehicle. The vehicle has been tested for path following and position accuracy. Based on the results a new...... vehicle is under construction....

  14. Field sprayer for inter and intra-row weed control: performance and labor savings

    Directory of Open Access Journals (Sweden)

    J. Carballido

    2013-07-01

    Full Text Available Studies of new tools and methods for weed control have been motivated by increased consumer demand for organic produce, consumer and regulatory demands for a reduction in environmentally harmful herbicide use, and the decreased availability of farm workers willing to perform manual tasks, such as hand weeding. This study describes the performance of a new sprayer system for commercial production that integrates two herbicide applications in a single pass, selective herbicide (SH application in narrow bands over the crop row, and a non-selective herbicide (NSH application between crop rows. A real-time kinematic (RTK global positioning system (GPS was used for auto-guidance in seeding and spraying operations. Conventional broadcast SHs and experimental treatments were applied at a constant nominal speed of 5.5 km h-1 for comparison. Trials in commercial sugar beet fields demonstrated the following: (i average hand-weeding time can be reduced by 53% (ii the new sprayer system reduced SH use by 76%, and (iii sugar beet density did not change significantly during treatment. These results demonstrate the feasibility of using the new RTK-GPS controller sprayer system for differential and efficient herbicide application in inter- and intra-row zones in row crop production.

  15. Weed Control and Corn (Zea mays Response to Planting Pattern and Herbicide Program with High Seeding Rates in North Carolina

    Directory of Open Access Journals (Sweden)

    Mitchell K. Williams

    2014-01-01

    Full Text Available Effective weed control in corn (Zea mays L. is important to optimize yield. Concern over environmental impact of atrazine and selection for glyphosate resistance has increased the need to develop alternative strategies that use herbicides other than atrazine and glyphosate and appropriate cultural practices to control weeds. Research was conducted during 2011 and 2012 to determine weed and corn response to herbicide programs containing dicamba, glufosinate, and glyphosate applied postemergence alone or with atrazine in single- and twin-row planting patterns. Planting pattern had no effect on common ragweed (Ambrosia artemisiifolia L. and Texas panicum (Panicum texanum L. population and did not interact with herbicide program. Effective weed control hastened maturity in some but not all instances. Under weed-free conditions, corn grain yield was higher in 5 of 7 trials when planted in twin rows versus single rows at equivalent corn populations (141,000 plants ha−1. These results suggest that while planting pattern may not impact weed control dramatically, planting corn in twin rows may be an effective alternative to single-row planting patterns because of increased yield under high corn populations.

  16. Chemical atributes of an oxisol submitted to weed control in coffee

    OpenAIRE

    2015-01-01

    In coffee culture, the inadequate control of invasive plants can degrade the soil used then managements practices to contribute to the improvement of quality physical, chemical and biological of the soil. Should be used the aim of this work were evaluated the influence of various weed control methods on some chemical properties of a Red-Yellow Latosol (RYL) cultivated with coffee. The experimental design was randomized block with strip plots, making a 9x2 factorial, nine control methods and t...

  17. Spring-Interseeded Winter Rye Seeding Rates Influence Weed Control and Organic Soybean Yield

    Directory of Open Access Journals (Sweden)

    Kelly A. Nelson

    2011-01-01

    Full Text Available Field research in 2002 and 2003 evaluated spring-interseeded winter rye (Secale cereale L. at 67, 134, or 200 kg ha−1 at two soybean (Glycine max (L. Merr. row spacings (19- and 76-cm on weed control, yield, and gross margins. Based on regression analysis, wide-row (76-cm soybean grain yield and gross margins were greatest when winter rye was interseeded at 114 and 106 kg ha−1, respectively. Yields and gross margins for wide-row soybean were 8 to 55% greater than narrow-row (19-cm soybean seeded at 494,000 or 742,000 seeds ha−1 which was probably due to flexibility for implementing cultivation. As interseeded rye rates increased from 67 to 200 kg ha−1, yields and gross margins for narrow-rows decreased. Soybean row spacing had minimal impacts on specific weed species and total weed biomass or density. The use of wide-row soybean and spring-interseeded rye at 67 kg ha−1 was more cost-effective compared to narrow rows.

  18. Herbicides as weed control agents: state of the art: II. Recent achievements.

    Science.gov (United States)

    Kraehmer, Hansjoerg; van Almsick, Andreas; Beffa, Roland; Dietrich, Hansjoerg; Eckes, Peter; Hacker, Erwin; Hain, Ruediger; Strek, Harry John; Stuebler, Hermann; Willms, Lothar

    2014-11-01

    In response to changing market dynamics, the discovery of new herbicides has declined significantly over the past few decades and has only seen a modest upsurge in recent years. Nevertheless, the few introductions have proven to be interesting and have brought useful innovation to the market. In addition, herbicide-tolerant or herbicide-resistant crop technologies have allowed the use of existing nonselective herbicides to be extended into crops. An increasing and now major challenge is being posed by the inexorable increase in biotypes of weeds that are resistant to herbicides. This problem is now at a level that threatens future agricultural productivity and needs to be better understood. If herbicides are to remain sustainable, then it is a must that we adopt diversity in crop rotation and herbicide use as well as increase the use of nonchemical measures to control weeds. Nevertheless, despite the difficulties posed by resistant weeds and increased regulatory hurdles, new screening tools promise to provide an upsurge of potential herbicide leads. Our industry urgently needs to supply agriculture with new, effective resistance-breaking herbicides along with strategies to sustain their utility.

  19. Bermudagrass: Spring weed control programs and biotype research

    Science.gov (United States)

    Research conducted from 2008 through 2012 evaluated bermudagrass control with Sencor (metribuzin) and Command (clomazone) plus Direx (diuron). Averaged across experiments, bermudagrass was controlled 54, 41, and 43% four weeks after Sencor application at 3 lb/A in mid-February, early-March, and mid-...

  20. Benzoxazinoids in rye allelopathy - from discovery to application in sustainable weed control and organic farming.

    Science.gov (United States)

    Schulz, Margot; Marocco, Adriano; Tabaglio, Vincenzo; Macias, Francisco A; Molinillo, Jose M G

    2013-02-01

    The allelopathic potency of rye (Secale cereale L.) is due mainly to the presence of phytotoxic benzoxazinones-compounds whose biosynthesis is developmentally regulated, with the highest accumulation in young tissue and a dependency on cultivar and environmental influences. Benzoxazinones can be released from residues of greenhouse-grown rye at levels between 12 and 20 kg/ha, with lower amounts exuded by living plants. In soil, benzoxazinones are subject to a cascade of transformation reactions, and levels in the range 0.5-5 kg/ha have been reported. Starting with the accumulation of less toxic benzoxazolinones, the transformation reactions in soil primarily lead to the production of phenoxazinones, acetamides, and malonamic acids. These reactions are associated with microbial activity in the soil. In addition to benzoxazinones, benzoxazolin-2(3H)-one (BOA) has been investigated for phytotoxic effects in weeds and crops. Exposure to BOA affects transcriptome, proteome, and metabolome patterns of the seedlings, inhibits germination and growth, and can induce death of sensitive species. Differences in the sensitivity of cultivars and ecotypes are due to different species-dependent strategies that have evolved to cope with BOA. These strategies include the rapid activation of detoxification reactions and extrusion of detoxified compounds. In contrast to sensitive ecotypes, tolerant ecotypes are less affected by exposure to BOA. Like the original compounds BOA and MBOA, all exuded detoxification products are converted to phenoxazinones, which can be degraded by several specialized fungi via the Fenton reaction. Because of their selectivity, specific activity, and presumably limited persistence in the soil, benzoxazinoids or rye residues are suitable means for weed control. In fact, rye is one of the best cool season cover crops and widely used because of its excellent weed suppressive potential. Breeding of benzoxazinoid resistant crops and of rye with high

  1. Biological control of weeds release sites : Kulm Wetland Management District

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Table of release sites of insects for biological control of invasive plants at Kulm Wetland Management District (WMD). Insects were released on Kulm WMD to...

  2. Effects of Weed Control and Cow Dung Manure on Growth ...

    African Journals Online (AJOL)

    control and cow dung manure treatments on growth of Quality Protein Maize. The trial consisted of factorial ... Maize (Zea mays L.) is one of the most important staple food crops in West and ... food production (Kamara and Sanginga, 2001). Of.

  3. Weed control by direct injection of plant protection products according to specific situations

    Directory of Open Access Journals (Sweden)

    Krebs, Mathias

    2016-02-01

    Full Text Available Precision Farming in agriculture allows a site-specific management of the crop. The aim of plant protection is to apply plant protection products (PPP according to the site specific requirements on the field. Within the context of a research program to promote innovation, a sprayer with direct injection of plant protection products was developed. The direct injection offers site specific spraying of different individual PPP in a single pass. The sprayer prototype is equipped with a special spray boom combining three nozzle lines. In order to prevent delay times, the nozzle lines are preloaded before spraying. First results for weed control from test stand measurements and field trials showed that the injection pumps work with high accuracy. The prototype can be used without delay times site specific with up to three different herbicides. Field trials for site-specific weed control in winter wheat demonstrate the applicability of the system under practical conditions. By treatment of subareas herbicides and therefore costs could be saved. A reduction in yield compared with the conventionally treated field areas could not be ascertained. Also an efficacy reduction through washout of active ingredient from target surfaces due to simultaneous use of all three nozzle lines with up to 1050 l/ha application rate could not be detected. At high water spray rates, the efficacy effect occurs delayed. Overall, the newly developed direct injection system proved fieldabillity during the first tests. So weed control can be carried out situation-responsive, which can save herbicides and environmental impacts are reduced.

  4. Lawn Weed Control with Herbicides. Home and Garden Bulletin No. 123.

    Science.gov (United States)

    Agricultural Research Service (USDA), Washington, DC.

    Information and diagrams are given for identification and treatment of weed grasses and broadleaf weeds. Herbicides are suggested for use against each weed and instructions are given for proper application. Information is given for buying herbicides, and applying sprays and cleaning sprayers. (BB)

  5. Seed preferences by rodents in the agri-environment and implications for biological weed control.

    Science.gov (United States)

    Fischer, Christina; Türke, Manfred

    2016-08-01

    Post-dispersal seed predation and endozoochorous seed dispersal are two antagonistic processes in relation to plant recruitment, but rely on similar preconditions such as feeding behavior of seed consumers and seed traits. In agricultural landscapes, rodents are considered important seed predators, thereby potentially providing regulating ecosystem services in terms of biological weed control. However, their potential to disperse seeds endozoochorously is largely unknown. We exposed seeds of arable plant species with different seed traits (seed weight, nutrient content) and different Red List status in an experimental rye field and assessed seed removal by rodents. In a complementary laboratory experiment, consumption rates, feeding preferences, and potential endozoochory by two vole species (Microtus arvalis and Myodes glareolus) were tested. Seed consumption by rodents after 24 h was 35% in the field and 90% in the laboratory. Both vole species preferred nutrient-rich over nutrient-poor seeds and M. glareolus further preferred light over heavy seeds and seeds of common over those of endangered plants. Endozoochory by voles could be neglected for all tested plant species as no seeds germinated, and only few intact seeds could be retrieved from feces. Synthesis and applications. Our results suggest that voles can provide regulating services in agricultural landscapes by depleting the seed shadow of weeds, rather than facilitating plant recruitment by endozoochory. In the laboratory, endangered arable plants were less preferred by voles than noxious weeds, and thus, our results provide implications for seed choice in restoration approaches. However, other factors such as seed and predator densities need to be taken into account to reliably predict the impact of rodents on the seed fate of arable plants.

  6. Integrated Weed Control for Land Stewardship at Legacy Management's Rocky Flats Site in Colorado - 13086

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Jody K. [Stoller LMS Team, Contractor to the U.S. Department of Energy Office of Legacy Management, 11025 Dover Street, Suite 1000, Westminster, Colorado 80021 (United States)

    2013-07-01

    Land stewardship is one of nine sustainability programs in the U.S. Department of Energy's Environmental Management System. Land stewardship includes maintaining and improving ecosystem health. At the Rocky Flats Site near Westminster, Colorado, land stewardship is an integral component of the Office of Legacy Management's post-closure monitoring and management at the site. Nearly 263 hectares (650 acres) were disturbed and re-vegetated during site cleanup and closure operations. Proactive management of revegetation areas is critical to the successful reestablishment of native grasslands, wetlands, and riparian communities. The undisturbed native plant communities that occur at the site also require active management to maintain the high-quality wetlands and other habitats that are home to numerous species of birds and other wildlife such as elk and deer, rare plant communities, and the federally listed threatened Preble's meadow jumping mouse. Over the past several decades, an increase of Noxious weeds has impacted much of Colorado's Front Range. As a result, weed control is a key component of the land stewardship program at Rocky Flats. Thirty-three species of state-listed Noxious weeds are known to occur in the Central and Peripheral Operable Units at Rocky Flats, along with another five species that are considered invasive at the site. Early detection and rapid response to control new invasive species is crucial to the program. An integrated weed control/vegetation management approach is key to maintaining healthy, sustainable plant communities that are able to resist Noxious weed invasions. Weed mapping, field surveys, and field-staff training sessions (to learn how to identify new potential problem species) are conducted to help detect and prevent new weed problems. The integrated approach at Rocky Flats includes administrative and cultural techniques (prevention), mechanical controls, biological controls, and chemical controls. Several

  7. Chitosan/tripolyphosphate nanoparticles loaded with paraquat herbicide: an environmentally safer alternative for weed control.

    Science.gov (United States)

    Grillo, Renato; Pereira, Anderson E S; Nishisaka, Caroline S; de Lima, Renata; Oehlke, Kathleen; Greiner, Ralf; Fraceto, Leonardo F

    2014-08-15

    Paraquat is a fast acting nonselective contact herbicide that is extensively used worldwide. However, the aqueous solubility and soil sorption of this compound can cause problems of toxicity in nontarget organisms. This work investigates the preparation and characterization of nanoparticles composed of chitosan and sodium tripolyphosphate (TPP) to produce an efficient herbicidal formulation that was less toxic and could be used for safer control of weeds in agriculture. The toxicities of the formulations were evaluated using cell culture viability assays and the Allium cepa chromosome aberration test. The herbicidal activity was investigated in cultivations of maize (Zea mays) and mustard (Brassica sp.), and soil sorption of the nanoencapsulated herbicide was measured. The efficiency association of paraquat with the nanoparticles was 62.6 ± 0.7%. Encapsulation of the herbicide resulted in changes in its diffusion and release as well as its sorption by soil. Cytotoxicity and genotoxicity assays showed that the nanoencapsulated herbicide was less toxic than the pure compound, indicating its potential to control weeds while at the same time reducing environmental impacts. Measurements of herbicidal activity showed that the effectiveness of paraquat was preserved after encapsulation. It was concluded that the encapsulation of paraquat in nanoparticles can provide a useful means of reducing adverse impacts on human health and the environment, and that the formulation therefore has potential for use in agriculture.

  8. A new perspective with weed management

    Science.gov (United States)

    No-till cropping systems are increasing land productivity. Herbicides are a crucial tool for weed management in no-till, but weed resistance is decreasing control efficacy and increasing input costs. Producers are seeking a broader perspective with weed management. One approach is to disrupt weed...

  9. Bioactive compound from mangoes leaves extract as potential soil bioherbicide to control amaranth weed (Amaranthus spinosus Linn.

    Directory of Open Access Journals (Sweden)

    Rifauldin Syahri

    2017-04-01

    Full Text Available Bioherbicide is important approach for sustainable farming practices. One of plant that has potentially as bioherbicide, which is environmentally safe, is mango. Mango leaf extract is useful as bioherbicide because it produces allelochemical compounds, which could inhibit the weed growth. This research was designed to study the effect of several mangoes species leaves extract to control dominant weed (amaranth. Split plot design was implemented using mango species (S as the main plot; S1 (Mangifera odorata Griff., S2 (Mangifera foetida Lour and S3 (Mangifera indica L.. While the sub plots were concentrations of mango’s leaf extract (K, that included 0, 500, 1000, 1500, and 2000 ppm. Results of the research showed that all parameters of weed growth (amaranth were inhibited along with the increase of concentration of the mango’s leaf extract. The results also showed the significant inhibition of amaranth’s dry weight. Among three species of mangoes, M. indica L. showed the best inhibition mechanism to the amaranth weed, which significantly suppressed the weed growth on just 1000 ppm concentration.

  10. Growth analysis and yield of two varieties of groundnut (Arachis hypogaea L.) as influenced by different weed control methods.

    Science.gov (United States)

    Olayinka, Bolaji U; Etejere, Emmanuel O

    Field trials were carried out to evaluate the effects of seven weed management strategies on the growth and yield of two groundnut varieties (Samnut 10 and MK 373) for two successive seasons (2010-2011). The experimental layout was a split plot complete randomized block design with three replications. The two groundnut varieties showed identical pattern of results for leaf area index, dry matter accumulation, relative growth rate, net assimilation rate and crop growth rate as well as yield. All the weed control treatments significantly enhanced the growth and yield compared with the weedy check. The weed free check had the highest growth but the highest yield was recorded from rice straw mulch at 0.1 m depth + one hand weeding at 6 weeks after sowing (WAS) due to increase in number of matured pods per plant, seed weight per plant and 100-seed weight. The results showed that rice straw mulch at 0.1 m depth + one hand weeding at 6 WAS was better agronomical practice for enhancing growth and yield of groundnut. This enhancement could be as a result of its positive influence on physiological parameters such as leaf area index, dry matter accumulation, relative growth rate, net assimilation rate and crop growth rate. Its use is also ecofriendly as it limits the need for synthetic herbicide.

  11. Complex Outcomes from Insect and Weed Control with Transgenic Plants: Ecological Surprises?

    Directory of Open Access Journals (Sweden)

    Thomas Bøhn

    2017-09-01

    Full Text Available Agriculture is fundamental for human survival through food production and is performed in ecosystems that, while simplified, still operate along ecological principles and retain complexity. Agricultural plants are thus part of ecological systems, and interact in complex ways with the surrounding terrestrial, soil, and aquatic habitats. We discuss three case studies that demonstrate how agricultural solutions to pest and weed control, if they overlook important ecological and evolutionary factors, cause “surprises”: (i the fast emergence of resistance against the crop-inserted Bt-toxin in South Africa, (ii the ecological changes generated by Bt-cotton landscapes in China, and (iii the decline of the monarch butterfly, Danaus plexippus, in North America. The recognition that we work with complex systems is in itself important, as it should limit the belief in reductionist solutions. Agricultural practices lacking eco-evolutionary understanding result in “surprises” like resistance evolution both in weeds and pest insects, risking the reappearance of the “pesticide treadmill”—with increased use of toxic pesticides as the follow-up. We recommend prioritization of research that counteracts the tendencies of reductionist approaches. These may be beneficial on a short term, but with trade-off costs on a medium- to long-term. Such costs include loss of biodiversity, ecosystem services, long-term soil productivity, pollution, and reduced food quality.

  12. Controle pós-emergente de plantas daninhas em cenoura Post-emergence weed control in carrot crop

    Directory of Open Access Journals (Sweden)

    Jeferson Zagonel

    1999-03-01

    Full Text Available O experimento foi conduzido em Piraí do Sul-PR no ano de 1995 em solo de textura argilo arenosa, tendo como objetivo avaliar a eficiência e a seletividade do herbicida propaquizafop no controle pós-emergente de plantas daninhas na cultura da cenoura. O delineamento experimental utilizado foi de blocos ao acaso com seis tratamentos e quatro repetições, quais sejam: propaquizafop (100, 125 e 150 g i.a./ha; fluazifop-p-butil (188 g i.a./ha; testemunha capinada e testemunha sem capina. A cultivar de cenoura utilizada foi Nantes Tim Tom semeada em 15 de junho, com espaçamento de 0,25 x 0,05 m, em parcelas com área útil de 5,00 x 1,00 m. As plantas daninhas predominantes foram Brachiaria plantaginea (capim-papuã, Digitaria horizontalis (capim-milhã e Eleusine indica (capim pé-de-galinha. As avaliações foram efetuadas aos 15, 30 e 45 dias após a aplicação dos tratamentos. Observou-se que o herbicida propaquizafop, nas doses de 100, 125 e 150 g i.a./ha foi eficiente no controle sobre capim-papuã, capim-milhã e capim pé-de-galinha. O controle de plantas daninhas realizado através de herbicidas proporcionou a mesma produção obtida com o controle manual. A perda na produção ocasionada pela presença de plantas daninhas foi da ordem de 76,4%. Não foram observados efeitos fitotóxicos nas plantas de cenoura que pudessem ser atribuídos aos produtos utilizados.The presented field trial was conducted in 1995 in Piraí do Sul, Paraná State, Brazil, on a sand-clay texture soil, to evaluate the efficiency and selectivity of propaquizafop on carrot crop weed control. The experiment was laid out in a randomized block design with six treatments and four replications, and 5.00 x 1.00 m plots. The treatmens were: propaquizafop (100, 125 and 150 g a.i/ha; fluazifop-p-butil (188 g a.i/ha; control with weeding and control without weeding. The carrot cultivar Nantes Tim Tom was sown on June 15 with plants spaced 0.25 x 0.05 m. The prevalent weeds

  13. The Effect of Nozzle Types and Time of Herbicide Incorporation in Soil on Corn (Zea mays L. Weed Control

    Directory of Open Access Journals (Sweden)

    K Gerami

    2012-09-01

    Full Text Available This experiment was conducted to study the effect of nozzle types and the time of herbicide incorporation in soil on weed control, using split plot design by randomized block design. The main plots were soil and herbicide mixing time and the subplots were nozzle types with three replications. This study was performed in Karaj station of Seed and Plant Improvement Institute, located 25 km west of Tehran, in 2008. Treatments were including: T-Jet standard nozzle, Flood-Jet nozzle and Air induction nozzle as well as mixing with the soil immediately, three, six and nine hours after spraying. The parameters were measured includes: the number of weeds before spraying, 15 days and 30 days after spraying; dry weed at two stages of 15 and 30 days after the spraying; and yield of corn. The results revealed that the spraying quality coefficient was greater for T-jet nozzle compared to the other types. However Flood-jet nozzle had a wide range of corn weeds control in comparison to other treatments. Regardless of the nozzle type, the immediate incorporation of herbicide in soil after spraying significantly increased the yield. The time of herbicide incorporation in soil and poison intermixture with soil, from zero to 4.5 hours after spraying was superior to the other times. This was mainly due to different weeds reactions to the times of herbicide incorporation in soil after spraying, and also treatments effect on yield and weed dry weight. Combined data analysis showed that treatment combination of T-Jet nozzle (with time of herbicide incorporation in soil immediately and three hours after spraying, Flood-jet nozzle (with time of herbicide incorporation in soil immediately after spraying and air induction nozzle (with time of herbicide incorporation in soil immediately, three and six hours after spraying produced the highest yield than the other treatment combinations.

  14. Effect of Tillage in Day or Night and Application of Reduced Dosage of Imazethapyr and Trifluralin on Weed Control, Yield and Yield Components of Chickpea

    Directory of Open Access Journals (Sweden)

    A Abbasian

    2015-07-01

    Full Text Available This Experiment was arranged as a strip-plot on the base of a completely randomized block design with three replications to study the effect of tillage (whether in day or night or in day by light-proof cover and application of reduced dosage of imazethapyr and trifluralin on weed control, yield and yield components of chickpea. Main plots consisted of tillage methods and subplots consisted of trifluralin (at doses of 480, 960 and 1440 g ai /ha and imazethapyr (at doses of 50, 100 and 150 g ai /ha, plus weed free and weedy checks. Results showed weed biomass in day tillage, night tillage and in light-proof cover tillage were respectively 86, 127 and 148 g m-2. Therefore tillage at night or by light-proof cover in day time showed not enough efficiency in weed control. Weed biomass increased when application dose of herbicides decreased. Chickpea grain yield showed significant differences when different doses of herbicides applied. The minimum and the maximum seed yield were obtained respectively in weed free (by 208 g m-2 and weedy checks (by 123 g m-2. Reduced dosage of imazethapyr and trifluralin could control weeds good enough by no significant decrease in chickpea yield. Efficacy of imazethapyr to control weeds grown in chickpea was significantly better than that of trifluralin

  15. Evaluation of an autonomous GPS-based system for intra-row weed control by assessing the tilled area

    DEFF Research Database (Denmark)

    Nørremark, Michael; Griepentrog, Hans W.; Nielsen, Jon;

    2012-01-01

    -1 and at even plant spacing. A double pass, once on each side of the row in opposite directions, provided higher soil disturbance intensity and resulted in tillage of 31–58% of the intra-row area with highest coverage at a speed of 0.32 m s-1. The intra-row weed control effect was predicted to be up...

  16. Enhanced degradation of atrazine under field conditions correlates with a loss of weed control in the glasshouse.

    Science.gov (United States)

    Krutz, L Jason; Zablotowicz, Robert M; Reddy, Krishna N; Koger, Clifford H; Weaver, Mark A

    2007-01-01

    Enhanced degradation of atrazine has been reported in the literature, indicating the potential for reduced residual weed control with this herbicide. Experiments were conducted to determine the field dissipation of atrazine in three cropping systems: continuous Zea mays L. (CC) receiving atrazine applications each year, Gossypium hirsutum L.-Z. mays rotation (CCR) receiving applications of atrazine once every 2 years and a no atrazine history soil (NAH). Subsequent laboratory and greenhouse experiments were conducted with soil collected from these cropping systems to determine atrazine degradation, mineralization and residual weed control. Field dissipation of atrazine followed first-order kinetics, and calculated half-life values for atrazine combined over 2003 and 2005 increased in the order of CC (9 d) = CCR (10 d) atrazine was approximately twofold greater in NAH soil than in CC or CCR soil. Biometer flask mineralization studies suggested that enhanced degradation of atrazine was due to rapid catabolism of the s-triazine ring. Glasshouse efficacy studies revealed a loss of residual weed control in CC and CCR soil compared with NAH soil. These data indicate that, under typical Mississippi Delta field conditions and agronomic practices, the persistence of atrazine may be reduced by at least 50% if the herbicide is applied more than once every 24 months. Glasshouse studies suggest that under these conditions a loss of residual weed control is possible.

  17. Introduction to Agronomy, Grain Crops, Weeds and Controls. A Learning Activity Pac in Agricultural Education Courses in Wisconsin.

    Science.gov (United States)

    Wisconsin State Dept. of Public Instruction, Madison. Div. of Instructional Services.

    This learning activity pac contains information to help the teachers of high school vocational agriculture in the instructional area of agronomy. Each of the two main sections, grain crops and weeds and controls, includes teacher and student units for the section lessons. Teacher units include special instructions--equipment needed (film…

  18. Proceedings of the XIII International Symposium on Biological Control of Weeds; September 11-16, 2011; Waikoloa, Hawaii, USA

    Science.gov (United States)

    Yun Wu; Tracy Johnson; Sharlene Sing; S. Raghu; Greg Wheeler; Paul Pratt; Keith Warner; Ted Center; John Goolsby; Richard Reardon

    2013-01-01

    A total of 208 participants from 78 organizations in 19 countries gathered at the Waikoloa Beach Marriott on the Big Island of Hawaii on September 11-16, 2011 for the XIII International Symposium on Biological Control of Weeds. Following a reception on the first evening, Symposium co-chairs Tracy Johnson and Pat Conant formally welcomed the attendees on the morning of...

  19. CONTROL DE MALEZA EN DISTRITOS DE RIEGO CON EQUIPOS LIGEROS WEED CONTROL IN IRRIGATION DISTRICTS WITH LIGHT WEIGHT EQUIPMENT

    Directory of Open Access Journals (Sweden)

    José Ramón Lomelí Villanueva

    2010-12-01

    Full Text Available En México el control mecánico de maleza, tradicionalmente se realizaba con maquinaria inadecuada lo cual provocaba daños en los taludes y modificaciones de la sección hidráulica. Para resolver este problema, actualmente se utilizan los equipos ligeros que permiten el desarrollo de una cubierta vegetal, que no interfiere con el flujo del agua y su sistema radical retiene el suelo, lo cual reduce la erosión y mantiene en condiciones estables los taludes. El presente trabajo aborda los aspectos relativos a características y criterios para la selección de los implementos y la secuencia para su utilización. El costo de las operaciones para el control de maleza en canales, drenes y caminos se ha reducido un 39,21% con respecto a utilizar maquinaria inadecuada. La versatilidad de los equipos ligeros permite emplear el implemento más adecuado para cada tipo de maleza. En México, el inventario actual es de 263 equipos ligeros que tienen un potencial de aplicación para el control de la maleza, en la totalidad de los caminos, el 90% de canales y el 70% de drenes de los Distritos de Riego.In Mexico, the mechanical weed control was traditionally carried out with inadequate equipment which caused damage to the slopes and changes in the hydraulic section. In order to solve this problem, light weight equipment is currently being used to allow the development of a vegetation cover to retain soil with no interference with water flow, reducing erosion and maintaining stable conditions in the slopes. This paper addresses aspects related to characteristics and criteria for selecting and sequencing tools for use. The costs of weed control in irrigation channels, drains and roads have been reduced 39.21% compared to using inadequate equipment. The versatility of light weight equipment allows the use of the most appropriate implement for each weed. In Mexico, the current inventory includes 263 light weight devices with which a potential weed control of 90

  20. Efeito de diferentes períodos de controle das plantas daninhas na produtividade da cultura da cebola Effect of different weed control periods on onion crop yield

    Directory of Open Access Journals (Sweden)

    D.J. Soares

    2004-12-01

    Full Text Available Foi realizado um experimento em Monte Alto-SP, visando estudar os efeitos de diferentes períodos de controle das plantas daninhas sobre a produção de bulbos da cultura da cebola (Allium cepa, cultivar 'Mercedes', no sistema de transplantio. O delineamento experimental utilizado foi o de blocos ao acaso, com quatro repetições. Parte dos tratamentos experimentais foi disposta num esquema fatorial 4 x 6, em que constituíram variáveis quatro períodos em que se fez o controle (0-0, 0-7, 0-14 e 0-21 DAT e seis períodos em que se reiniciou o controle das plantas daninhas prolongando até a colheita: 28, 42, 56, 70, 84 e 98 DAT. Duas testemunhas foram adotadas: uma com controle e outra sem controle das plantas daninhas durante todo o ciclo da cultura. Lycopersicon esculentum, Portulaca oleracea, Eragrostis pilosa e Galinsoga parviflora foram as plantas daninhas mais importantes na área. Não houve interação entre os diferentes períodos de controle das plantas daninhas. O controle inicial destas plantas deve se prolongar até 14 DAT e ser reiniciado aos 28 DAT, a fim de prevenir reduções significativas na produtividade em relação à testemunha no limpo A convivência com as plantas daninhas durante todo o ciclo da cebola reduziu a produtividade em 94,5%.An experiment was carried out in Monte Alto, SP to study the effects of different of weed control periods on the yield of onion (Allium cepa bulb, 'Mercedes' cultivar, under the transplanting system. The experiment was arranged in a completely randomized block design, with four replications. The treatments were arranged in 4 x 6 factorial design with four initial weed removal periods (after transplanting until 0, 7, 14 and 21 days and six final weed removal periods (from 28, 42, 56, 70, 84 or 98 days after transplanting until harvest. Two controls were adapted with and without weed control throughout the onion cycle. Lycopersicon esculentum, Portulaca oleracea, Eragrostis pilosa and

  1. The development of a phosphite-mediated fertilization and weed control system for rice

    Science.gov (United States)

    Manna, Mrinalini; Achary, V. Mohan M.; Islam, Tahmina; Agrawal, Pawan K.; Reddy, Malireddy K.

    2016-01-01

    Fertilizers and herbicides are two vital components of modern agriculture. The imminent danger of phosphate reserve depletion and multiple herbicide tolerance casts doubt on agricultural sustainability in the future. Phosphite, a reduced form of phosphorus, has been proposed as an alternative fertilizer and herbicide that would address the above problems to a considerable extent. To assess the suitability of a phosphite-based fertilization and weed control system for rice, we engineered rice plants with a codon-optimized ptxD gene from Pseudomonas stutzeri. Ectopic expression of this gene led to improved root growth, physiology and overall phenotype in addition to normal yield in transgenic plants in the presence of phosphite. Phosphite functioned as a translocative, non-selective, pre- and post-emergent herbicide. Phosphite use as a dual fertilizer and herbicide may mitigate the overuse of phosphorus fertilizers and reduce eutrophication and the development of herbicide resistance, which in turn will improve the sustainability of agriculture. PMID:27109389

  2. Possibilities of chemical weed control in Lupinus albus and Lupinus luteus-screening of herbicides.

    Science.gov (United States)

    Dewitte, K; Latré, J; Haesaert, G

    2006-01-01

    Weed control in sweet lupins is still a problem. Especially the phytotoxicity of herbicides in sweet lupins is not enough studied. Therefore a screening with 16 selected herbicides and 4 lupin varieties has been set up. During the growing season 2005, 10 of the tested herbicides were applied in pre-emergence, 6 in post-emergence. Pre-emergence: Most of the active matters tested in pre-emergence were not phytotoxic for lupins. Pendimethalin (1000 g/ha), linuron (500 g/ha), chlorotoluron (1500 g/ha), prosulfocarb (2400 g/ha), clomazone (72 g/ha), isoxaben (100 g/ha), metamitron (1050 g/ha) and dimethenamid-P (720 g/ha) were applied without causing any significant phytotoxic symptoms. Only the lupins treated with aclonifen (1200 g/ha) showed a significant growth inhibition, 3 weeks after treatment. Significantly more chlorosis was noticed when the lupins were treated with aclonifen or with diflufenican, in preemergence. Post-emergence: In post-emergence, diflufenican (50 g/ha) did not cause any crop damage. Florasulam (5 g/ha) caused almost 100% necrosis in L. albus as well as in L. luteus. Bentazon (652 g/ha), thifensulfuron-methyl (15 g/ha) and metribuzin (175 g/ha) caused obvious necrosis and growth inhibition of the crop. The growth inhibition was significantly more severe for lupins treated with bentazon than if they were treated with thifensulfuron-methyl or metribuzin. Three weeks after treatment, clomazone (90 g/ha) and diflufenican (50 g/ha), did not cause any crop injury at all. The results indicated an interesting range of active matters which can be applied in pre-emergence, but weed control in post-emergence stays difficult.

  3. Controlling herbicide-resistant weeds: consider incorporating alfalfa in a corn/soybean rotation

    Science.gov (United States)

    Herbicide resistant weeds (HRW) are a serious problem in the U.S. In 1968, the first confirmed case of herbicide resistance in weeds was reported in Washington state. In the 46 years since, the number of HRW in the U.S. has increased dramatically. A major reason for the recent increase in HRW has be...

  4. 麻类作物田杂草种类与防除技术%Classification and Control Techniques of Weeds in Hemp Crops Field

    Institute of Scientific and Technical Information of China (English)

    孟桂元; 邬腊梅; 周静; 柏连阳

    2011-01-01

    Weeds were always growing associate with hemp crops in the field resulting in a competition of water, light and fertilizer, which could seriously affect the growth,yield and quality of hemp crops. Therefore,effectively controlling weeds in the field of hemp crops is particularly necessary. In this paper, the current situation of hemp crop production, weed species , infestation of main weeds, and weed control techniques were outlined in the fields of herm crops in China.%杂草常伴随麻类作物滋生,与其争光争肥争水,严重影响其生长、降低产量和品质.因此,有效防除麻田杂草尤为必要.文章概述了我国麻类作物生产现状,主要麻类作物田杂草危害、杂草种类及防除技术.

  5. Chemical and Mechanical Weed Control Methods and Their Effects on Photosynthetic Pigments and Grain Yield of Kidney Bean

    Directory of Open Access Journals (Sweden)

    A.S Ghatari

    2015-11-01

    Full Text Available To evaluate the integrated management of weeds in red kidney bean, a split-plot experiment using randomized complete block design with three replications was conducted in 2013 in the Damavand County. In this experiment, the mechanical control treatments consisted of two levels (no cultivation and one cultivation asseigned to main plots and controlling chemical treatments consisted of six levels (non-application of herbicides, pre-emergence herbicide application of Pursuit with full dose of 1 liter per hectare, pre-emergence herbicide application of Pursuit a dose decreased 0.5 liters per hectare, post-emergence herbicide application of Pursuit dose reduced to 0.3 liters per hectare + 2 thousand citogate, post-emergence herbicide application of Pursuit with a reduced dose of 0.5 liters per hectare + 2 thousand citogate, post-emergence herbicide application of Pursuit full dose of 1 liter per hectar + 2 thousand citogate to subplots. The results showed that the effects of interaction between herbicide application and cultivation for traits of carotenoids, chlorophyll a, chlorophyll b and total chlorophyll contents, density of weeds and their dry weights were significant at 1 %, and grain yield at the 5% probability levels. The highest bean seed yield with an average of 5461.6 kg.ha-1 and lowest weed dry weight with an average of 345.9 kg.ha-1 were related to pre-emergence herbicide and cultivation with a dose of 1 liter per hectare treatment. The difference between full and reduced doses of chemical weed control was non-significant. It could be concluded that integrated mechanical and chemical weed control not only may increase seed yield but also reduce, environmental hazards.

  6. Downy Brome (Bromus tectorum L. and Broadleaf Weed Control in Winter Wheat with Acetolactate Synthase-Inhibiting Herbicides

    Directory of Open Access Journals (Sweden)

    Patrick W. Geier

    2013-04-01

    Full Text Available A study was conducted for three seasons in northwest Kansas, USA to evaluate acetolactate synthase (ALS-inhibiting herbicides for downy brome (Bromus tectorum L. and winter annual broadleaf weed control in winter wheat. Herbicides included pyroxsulam at 18.4 g ai ha−1, propoxycarbazone-Na at 44 g ai ha−1, premixed propoxycarbazone-Na & mesosulfuron-methyl at 27 g ai ha−1, and sulfosulfuron at 35 g ai ha−1. The herbicides were applied postemergence in fall and spring seasons. Averaged over time of application, no herbicide controlled downy brome more than 78% in any year. When downy brome densities were high, control was less than 60%. Pyroxsulam controlled downy brome greater than or similar to other herbicides tested. Flixweed (Descurainia sophia L., blue mustard [Chorispora tenella (Pallas DC.], and henbit (Lamium amplexicaule L. control did not differ among herbicide treatments. All herbicides tested controlled flixweed and blue mustard at least 87% and 94%, respectively. However, none of the herbicides controlled henbit more than 73%. Fall herbicide applications improved weed control compared to early spring applications; improvement ranged from 3% to 31% depending on the weed species. Henbit control was greatly decreased by delaying herbicide applications until spring compared to fall applications (49% vs. 80% control. Herbicide injury was observed in only two instances. The injury was ≤13% with no difference between herbicides and the injury did not impact final plant height or grain yield.

  7. Weed Control in Corn (Zea mays L. as Influenced by Preemergence Herbicides

    Directory of Open Access Journals (Sweden)

    Travis W. Janak

    2016-01-01

    Full Text Available Field studies were conducted in central and south-central Texas from 2013 through 2015 to evaluate crop tolerance and efficacy of various preemergence herbicides alone and in combination for weed control in field corn. Acetochlor and pendimethalin alone, S-metolachlor plus mesotrione, and the three-way combination of S-metolachlor plus atrazine plus mesotrione provided the most consistent control of annual grasses including browntop panicum (Panicum fasciculatum L., Texas millet (Urochloa texana L., barnyardgrass (Echinochloa crus-galli L., and sprawling signalgrass (Brachiaria reptans L.. Palmer amaranth [Amaranthus palmeri (S. Wats.] control was at least 90% with fluthiacet-methyl plus pyroxasulfone, atrazine plus either acetochlor, alachlor, dimethenamid-P, S-metolachlor, or S-metolachlor plus mesotrione, saflufenacil plus dimethenamid-P, and S-metolachlor plus mesotrione. Hophornbeam copperleaf (Acalypha ostryifolia L. was difficult to control; however, acetochlor, saflufenacil or pyroxasulfone alone, saflufenacil plus dimethenamid-P, and S-metolachlor plus mesotrione provided at least 90% control. Acetochlor or saflufenacil alone, thiencarbazone-methyl plus isoxaflutole, dimethenamid-P plus atrazine, rimsulfuron plus mesotrione, and saflufenacil plus dimethenamid-P controlled common sunflower (Helianthus annuus L. at least 90%. Corn injury was minimal (≤3% with all herbicides. In general, corn grain yield was greatest with herbicide treatments containing more than one active ingredient compared with a single active ingredient.

  8. Effect of Row Intercropping Patterns on Yield, Yield Components, and Weed Control of Fenugreek (Trigonellafoenumgreacum L. and Anise (Pimpinellaanisum L.

    Directory of Open Access Journals (Sweden)

    F Mardani

    2016-02-01

    Full Text Available Introduction Due to population growth and food shortage agricultural production is on increasing demand. In this order increasing cultivation area and yield per unit area are two ways of obtaining higheragricultural production (20. There is another important way that without incurring additional costs and use of water and fertilizer could result in higher production. This approach is increasing agricultural production per unit area by growing more than one crop in a year. Intercropping will be successful when competition for sources issless than competition within a species. Plants in the mixture can be chosen in a way that a species benefits from environmental changes caused by other species in mixed cultures directly (7, 15. Intercropping inhibits the growth and development of weeds and leads to increased production. Since the system will reduce the pesticide use, environmental pollution will be also less proportionally (37. Materials and Methods In order to evaluate the yield, yield components and potential weeds control under intercropping fenugreek and anise, an experiment was carried out based on a randomized complete block design with three replicationsat the Agricultural Research Field of Yasouj University during growing season of 2012-2013. Treatments included pure cultures of fenugreek and anise, single-row, double-row and three-tier intercropping of fenugreek and anise at no weed control and weed control conditions. Results and Discussion The results showed that different intercropping treatments had significant effects on pod number per plant, grain weight and grain and biological yield of fenugreek and also, on number of lateral branches, number of grains per plant and grain and biological yield of anise. There were nosignificant effects on plant height, number of lateral branches, number of grain per pod, harvest index of fenugreek, as well as plant height, number of umbel let per plant, seed weight and harvest index of anise. The

  9. Chapter Three - Weed Dynamics and Management in Wheat

    DEFF Research Database (Denmark)

    Jabran, Khawar; Mahmood, Khalid; Melander, Bo

    2017-01-01

    pest of wheat causing in total 24% losses in wheat grain yield. In this chapter, we discuss the (i) weed flora in different wheat-growing regions of world; (ii) the yield losses caused by weeds in wheat; (iii) the preventive and cultural options for weed management; (iv) physical weed control; (v......) chemical weed control; and (vi) integrated weed management strategy in wheat. A critical analysis of recent literature indicated that broadleaved weeds are the most common group of weeds in wheat fields followed by grass weeds, while sedges were rarely noted in wheat fields. Across the globe, the most...... important weeds in wheat fields were Avena fatua L., Chenopodium album L., Phalaris minor Retz., Galium aparine L., Stellaria media (L.) Vill., and Veronica persica Poir., respectively. Adoption of wise weed management strategies may help control weeds and avoid yield losses. Both preventive measures...

  10. Control Effect of 80%Nicosulfuron·Atrazine Water-dispersible Granules on Weeds in Spring Maize Field

    Institute of Scientific and Technical Information of China (English)

    Yueqi SHEN; Rende Ql

    2014-01-01

    This study aimed to investigate the control effect of different concentrations of 80% nicosulfuron·atrazine water-dispersible granules on weeds in spring maize field. [Method] Maize field was sprayed with 300, 375, 450, 750 g/hm2 80% nicosulfuron·atrazine water-dispersible granules respectively, with 40 g/L nico-sulfuron suspending concentrate and 38% atrazine suspending concentrate as con-trol agents. Artificial weeding and control (CK) plots were set. [Result] Fresh weight control efficiency of 375-750 g/hm2 80% nicosulfuron ·atrazine water-dispersible granules was significantly higher than that of 40 g/L nicosulfuron suspending con-centrate and 38% atrazine suspending concentrate; no obvious phytotoxicity symp-toms were observed after application of 300-450 g/hm2 80% nicosulfuron·atrazine water-dispersible granules; 750 g/hm2 80% nicosulfuron·atrazine water-dispersible granules posed certain impact on the growth of maize seedlings. Compared with control plots, various doses of 80% nicosulfuron·atrazine water-dispersible granules signifi-cantly improved the yield of maize. [Conclusion] ln the present study, 375-450 g/hm2 80% nicosulfuron·atrazine water-dispersible granules exhibited high control effect on weeds in maize field and were safe for the growth of maize seedlings.

  11. Weed Control and Grain Sorghum (Sorghum bicolor Tolerance to Pyrasulfotole plus Bromoxynil

    Directory of Open Access Journals (Sweden)

    Dan D. Fromme

    2012-01-01

    Full Text Available Field studies were conducted during the 2008 and 2009 growing seasons at five locations in the Texas grain sorghum producing regions to evaluate pyrasulfotole plus bromoxynil combinations for weed control and grain sorghum response. All pyrasulfotole plus bromoxynil combinations controlled Amaranthus palmeri, Cucumis melo, and Proboscidea louisianica at least 94% while control of Urochloa texana was never better than 69%. Pyrasulfotole plus bromoxynil combinations did result in early season chlorosis and stunting; however, by the end of the growing season no visual injury or stunting differences were noted when compared to the untreated check. Early season grain sorghum chlorosis and stunting with pyrasulfotole plus bromoxynil combinations did not affect grain sorghum yields with the exception of pyrasulfotole at 0.03 kg ai/ha plus bromoxynil at 0.26 kg ai/ha plus atrazine at 0.58 kg ai/ha applied early postemergence followed by pyrasulfotole plus bromoxynil applied mid-postemergence which reduced yield at one of two locations in 2008. Grain sorghum yield increased following all pyrasulfotole plus bromoxynil treatments compared to the untreated check in 2009.

  12. WEED CONTROL METHODS AFFECT GROWTH, YIELD AND ECONOMIC RETURNS IN GROUNDNUT

    National Research Council Canada - National Science Library

    Bolaji Umar Olayinka; Emmanuel Obukohwo Etejere

    2016-01-01

    ... (Arachis hypogeal L cv Samnut 10 and MK 373). The results showed that Brachiaria deflexa, Cleome viscosa, Cochlospermum planchoni, Dactyloctenium aegyptium and Daniellia oliveri were the most preponderant in all twenty-six weed species encountered...

  13. Undercover predators: Vegetation mediates foraging, trophic cascades, and biological control by omnivorous weed seed predators

    OpenAIRE

    Blubaugh, Carmen K

    2015-01-01

    Weed pressure is the most costly challenge that vegetable growers face, requiring more labor investment than other production inputs. Vertebrate and invertebrate seed predators destroy a large percentage of weed propagules on the soil surface, and their ecosystem services may ease labor requirements for farmers in herbicide-free systems. Cover provided by living vegetation is an important predictor of seed predator activity, and my dissertation takes a comprehensive approach to understanding ...

  14. Secondary invasions of noxious weeds associated with control of invasive Tamarix are frequent, idiosyncratic and persistent

    Science.gov (United States)

    González, Eduardo; Sher, Anna A.; Anderson, Robert M.; Bay, Robin F.; Bean, Daniel W.; Bissonnete, Gabriel J.; Cooper, David J.; Dohrenwend, Kara; Eichhorst, Kim D.; El Waer, Hisham; Kennard, Deborah K.; Harms-Weissinger, Rebecca; Henry, Annie L.; Makarick, Lori J.; Ostoja, Steven M.; Reynolds, Lindsay V.; Robinson, W. Wright; Shafroth, Patrick B.; Tabacchi, Erich

    2017-01-01

    Control of invasive species within ecosystems may induce secondary invasions of non-target invaders replacing the first alien. We used four plant species listed as noxious by local authorities in riparian systems to discern whether 1) the severity of these secondary invasions was related to the control method applied to the first alien; and 2) which species that were secondary invaders persisted over time. In a collaborative study by 16 research institutions, we monitored plant species composition following control of non-native Tamarix trees along southwestern U.S. rivers using defoliation by an introduced biocontrol beetle, and three physical removal methods: mechanical using saws, heavy machinery, and burning in 244 treated and 79 untreated sites across six U.S. states. Physical removal favored secondary invasions immediately after Tamarix removal (0–3 yrs.), while in the biocontrol treatment, secondary invasions manifested later (> 5 yrs.). Within this general trend, the response of weeds to control was idiosyncratic; dependent on treatment type and invader. Two annual tumbleweeds that only reproduce by seed (Bassia scoparia and Salsola tragus) peaked immediately after physical Tamarix removal and persisted over time, even after herbicide application. Acroptilon repens, a perennial forb that vigorously reproduces by rhizomes, and Bromus tectorum, a very frequent annual grass before removal that only reproduces by seed, were most successful at biocontrol sites, and progressively spread as the canopy layer opened. These results demonstrate that strategies to control Tamarix affect secondary invasions differently among species and that time since disturbance is an important, generally overlooked, factor affecting response.

  15. IMPORTANCE OF CRITICAL PERIOD OF WEED COMPETITION FOR CROP GROWING

    Directory of Open Access Journals (Sweden)

    Marijana Ivanek-Martinčić

    2010-06-01

    Full Text Available A concept of critical period of weed competition has been introduced for more than 40 years ago. The concept is based on the assumption that weeds are not equally harmful to a crop during the whole season and that there is a period in crop development in which weeds impact on the yield is the biggest. This period is called critical period of weed competition (CPWC, critical period of weed interference, or critical period of weed control. There is a difference in CPWC between crops, but CPWC for a certain crop can vary a lot because it depends on many factors which can affect the crop or weeds competition ability. The critical period of weed competition identification is essential for integrated weed control and precise planning of a weed control strategy as well as for rationale use of herbicides and other weed control measures.

  16. Weed Control and Peanut Tolerance with Ethalfluralin-Based Herbicide Systems

    Directory of Open Access Journals (Sweden)

    W. J. Grichar

    2012-01-01

    Full Text Available Field studies were conducted from 2007 through 2009 to determine weed efficacy and peanut (Arachis hypogaea L. response to herbicide systems that included ethalfluralin applied preplant incorporated. Control of devil's claw (Proboscidea louisianica (Mill. Thellung, yellow nutsedge (Cyperus esculentus L., Palmer amaranth (Amaranthus palmeri S. Wats., and puncturevine (Tribulus terrestris L. was most consistent with ethalfluralin followed by either imazapic or imazethapyr applied postemergence. Peanut stunting was 19% when paraquat alone was applied early-postemergence. Stunting increased to greater than 30% when ethalfluralin applied preplant incorporated was followed by S-metolachlor applied preemergence and paraquat applied early-postemergence. Stunting (7% was also observed when ethalfluralin was followed by flumioxazin plus S-metolachlor applied preemergence with lactofen applied mid-postemergence. Ethalfluralin followed by paraquat applied early-postemergence reduced peanut yield when compared to the nontreated check. Ethalfluralin applied preplant incorporated followed by imazapic applied mid-postemergence provided the greatest yield (6220 kg/ha. None of the herbicide treatments reduced peanut grade (sound mature kernels plus sound splits when compared with the nontreated check.

  17. Flowers & Weeds.

    Science.gov (United States)

    Flannery, Maura C.

    1996-01-01

    Describes the topics and teaching strategies employed in an Issues in Biology course. Discusses flowers, plant breeding, potatoes and tomatoes, the chocolate tree, weeds, Arabidopis, gene transfers, and plant genes/human genes. Contains 22 references. (JRH)

  18. Flowers & Weeds.

    Science.gov (United States)

    Flannery, Maura C.

    1996-01-01

    Describes the topics and teaching strategies employed in an Issues in Biology course. Discusses flowers, plant breeding, potatoes and tomatoes, the chocolate tree, weeds, Arabidopis, gene transfers, and plant genes/human genes. Contains 22 references. (JRH)

  19. Bio-control potential of Cladosporium sp. (MCPL-461), against a noxious weed Parthenium hysterophorus L.

    Science.gov (United States)

    Kumar, Anuj; Verma, V C; Gond, S K; Kumar, V; Kharwar, R N

    2009-03-01

    The phenological survey of Parthenium hysterophorus L., in and around the campus of Banaras Hindu University (BHU) was done for about two years (2004-06). During Nov 2004, a few Parthenium plants were found diseased, and symptoms were restricted to the flowers, buds, and inflorescences. The disease causes sterility and reduces seed viability, which was observed with seed germination test from infected and healthy plants. The fungal pathogen was isolated and identified as Cladosporium sp. (MCPL-461). The severity of pathogen to the reproductive organs led to serious damages of the Parthenium plants. Thus in vitro and in vivo experiments were conducted to determine the bio-control potential of Cladosporium sp. (MCPL 461) against Parthenium weed. A combinatorial effort of Cladosporium sp. (MCPL 461) bio-control potential was evaluated with different culture media, incubation periods and spores strength. Spore suspension of 10(5) to 10(12) spores ml(-1) were used to spray on healthy Parthenium plants, and it was found that severe infection symptoms were appeared at 10(10) to 10(12) spores ml(-1) suspension. LD50 was found at 10(7) spores ml(-1). To enhance the myco-herbicide activity 3% sucrose was added to the spore suspension, which further resolute the bio-control efficacy of the isolates. Only 20-30% seeds of infected plants could germinate. However the safety of non-targeted and wild plants was also tested with Lantana camera, Chromolaena odorata and found that suspension up to 10(12) spores ml(-1) were not sufficient for disease outbreak in them.

  20. Efeito de período de controle de plantas daninhas na cultura de amendoim Effects of weed control periods on peanut crop

    Directory of Open Access Journals (Sweden)

    R.A. Pitelli

    2002-12-01

    Full Text Available Dois experimentos foram conduzidos com o objetivo de avaliar os efeitos de diferentes períodos de controle das plantas daninhas, sobre algumas características produtivas da cultura do amendoim. Os experimentos foram instalados no município de Taquaritinga-SP, em duas épocas de semeadura, sendo uma no cultivo "das secas", semeada durante o mês de março, e outra no cultivo "das águas", semeada durante o mês de setembro. Os tratamentos foram períodos de controle das plantas daninhas entre 017, 0-31, 0-45, 0-59, 0-73, 17-31, 17-45, 17-59, 17-73, 31-45, 31-59, 31-73, 45-59, 45-73 e 59-73 dias após a emergência da cultura. Foram mantidas duas testemunhas, uma sem controle e outra com controle das plantas daninhas durante todo o ciclo da cultura. A principal planta daninha, nos dois experimentos, foi Digitaria horizontalis. A comunidade infestante e a cultura foram influenciadas pela época de semeadura, modificando suas relações de interferência. No cultivo da época "das águas", os efeitos da convivência da comunidade infestante foram mais drásticos, afetando com maior intensidade a produtividade da cultura. Dentre as características produtivas avaliadas, o número de vagens por planta foi o principal fator na redução da produtividade. No cultivo "das águas", o controle somente foi necessário após os 45 dias iniciais de convivência, e na cultura "das secas", após os 59 dias, caracterizando os períodos anteriores à interferência. Nas duas épocas de semeadura o controle das plantas daninhas, realizado até 17 dias após a emergência, foi suficiente para garantir a produtividade da cultura semelhante à testemunha capina, caracterizando o período total de prevenção à interferência.Field trials were carried out to study the effect of weed control periods on some yield components of the peanut crop. Two experiments were carried out in Taquaritinga-SP, Brazil, one during the "dry season" (seeds sown in March, and the

  1. IAA Producing Enterobacter sp. I-3 as a Potent Bio-herbicide Candidate for Weed Control: A Special Reference with Lettuce Growth Inhibition

    OpenAIRE

    Park, Jae-Man; Radhakrishnan, Ramalingam; Kang, Sang-Mo; Lee, In-Jung

    2015-01-01

    Development of bio-herbicides is an emerging method to weed management in agricultural field. Very few studies were conducted on identification of microbial bio-herbicides to weed control. The present study was aimed to isolate and identify the effective bio-herbicide potential bacterium from soil and assess their role on plant growth inhibition. Three-hundred and one rhizobacteria were isolated from agriculture field soil samples collected from various parts of Republic of Korea. Two bacteri...

  2. What's a Weed? Knowledge, Attitude and Behaviour of Park Visitors about Weeds.

    Directory of Open Access Journals (Sweden)

    Michael Ansong

    Full Text Available Weeds are a major threat to biodiversity globally degrading natural areas of high conservation value. But what are our attitudes about weeds and their management including weeds in national parks? Do we know what a weed is? Do we consider weeds a problem? Do we support their management? Are we unintentionally spreading weeds in parks? To answer these questions, we surveyed visitors entering a large popular national park near the city of Brisbane, Australia. Park visitors were knowledgeable about weeds; with >75% correctly defining weeds as 'plants that grow where they are not wanted'. About 10% of the visitors, however, provided their own sophisticated definitions. This capacity to define weeds did not vary with people's age, sex or level of education. We constructed a scale measuring visitors' overall concern about weeds in parks using the responses to ten Likert scale statements. Over 85% of visitors were concerned about weeds with older visitors, hikers, and those who could correctly define weeds more concerned than their counterparts. The majority think visitors unintentionally introduce seeds into parks, with many (63% having found seeds on their own clothing. However, over a third disposed of these seeds in ways that could facilitate weed spread. Therefore, although most visitors were knowledgeable and concerned about weeds, and support their control, there is a clear need for more effective communication regarding the risk of visitors unintentionally dispersing weed seeds in parks.

  3. What's a Weed? Knowledge, Attitude and Behaviour of Park Visitors about Weeds.

    Science.gov (United States)

    Ansong, Michael; Pickering, Catherine

    2015-01-01

    Weeds are a major threat to biodiversity globally degrading natural areas of high conservation value. But what are our attitudes about weeds and their management including weeds in national parks? Do we know what a weed is? Do we consider weeds a problem? Do we support their management? Are we unintentionally spreading weeds in parks? To answer these questions, we surveyed visitors entering a large popular national park near the city of Brisbane, Australia. Park visitors were knowledgeable about weeds; with >75% correctly defining weeds as 'plants that grow where they are not wanted'. About 10% of the visitors, however, provided their own sophisticated definitions. This capacity to define weeds did not vary with people's age, sex or level of education. We constructed a scale measuring visitors' overall concern about weeds in parks using the responses to ten Likert scale statements. Over 85% of visitors were concerned about weeds with older visitors, hikers, and those who could correctly define weeds more concerned than their counterparts. The majority think visitors unintentionally introduce seeds into parks, with many (63%) having found seeds on their own clothing. However, over a third disposed of these seeds in ways that could facilitate weed spread. Therefore, although most visitors were knowledgeable and concerned about weeds, and support their control, there is a clear need for more effective communication regarding the risk of visitors unintentionally dispersing weed seeds in parks.

  4. What’s a Weed? Knowledge, Attitude and Behaviour of Park Visitors about Weeds

    Science.gov (United States)

    Ansong, Michael; Pickering, Catherine

    2015-01-01

    Weeds are a major threat to biodiversity globally degrading natural areas of high conservation value. But what are our attitudes about weeds and their management including weeds in national parks? Do we know what a weed is? Do we consider weeds a problem? Do we support their management? Are we unintentionally spreading weeds in parks? To answer these questions, we surveyed visitors entering a large popular national park near the city of Brisbane, Australia. Park visitors were knowledgeable about weeds; with >75% correctly defining weeds as ‘plants that grow where they are not wanted’. About 10% of the visitors, however, provided their own sophisticated definitions. This capacity to define weeds did not vary with people’s age, sex or level of education. We constructed a scale measuring visitors’ overall concern about weeds in parks using the responses to ten Likert scale statements. Over 85% of visitors were concerned about weeds with older visitors, hikers, and those who could correctly define weeds more concerned than their counterparts. The majority think visitors unintentionally introduce seeds into parks, with many (63%) having found seeds on their own clothing. However, over a third disposed of these seeds in ways that could facilitate weed spread. Therefore, although most visitors were knowledgeable and concerned about weeds, and support their control, there is a clear need for more effective communication regarding the risk of visitors unintentionally dispersing weed seeds in parks. PMID:26252004

  5. Weeding Your Collection.

    Science.gov (United States)

    Kerby, Ramona

    2002-01-01

    Offers guidelines for weeding as part of school library collection development. Highlights include developing a weeding policy; and the CREW (Continuous Review Evaluation and Weeding) method, including reasons for weeding, scheduling, and guidelines for fiction and for nonfiction. (LRW)

  6. Critical Period of Weed Control in Three Winter Oilseed Rape (Brassica napus L.) Cultivars

    OpenAIRE

    HAMZEI, Javad; NASAB, Adel Dabbagh Mohammady; KHOIE, Farrokh Rahimzadeh; JAVANSHIR, Aziz

    2007-01-01

    Field experiments were carried out at the Agricultural Research Station, Faculty of Agriculture, University of Tabriz, in 2004-2005 and 2005-2006. Three winter oilseed rape cultivars (Okapi, Licord, and SLM046) with 12 weed interference durations were evaluated in a factorial experiment based on a randomized complete block design with 3 replications. The experiments consisted of 2 sets of treatments. In the first set, the crop was kept weed-free until the growth stages of 4-leaf, 8-leaf, stem...

  7. MaisTer® Power: a Terbuthylazin free new solution to control monocotyledonous and dicotyledonous weeds in maize.

    Directory of Open Access Journals (Sweden)

    Wegener, Martin

    2014-02-01

    Full Text Available MaisTer® power is a combination of the well-known active ingredients Foramsulfuron (31,5 g/L, Iodosulfuron (1,04 g/L and the new developed ai Thiencarbazone-methyl (10,0 g/L and the new safener Cyprosulfamide (15,0 g/L. All three active ingredients belong to the group of the ALS inhibitors. The product can be applied with a dose rate of 1,5 L/ha or 1,0 L/ha. Foramsulfuron and Iodosulfuron will be taken up via the leaves of the plants whereas Thiencarbazone-methyl can penetrate the plants via the roots and the leaves. By using a dose rate of 1,5 L/ha a very good residual activity against new flushes of grass or broadleaf weeds will be observed. All relevant grass and broadleaf weeds in maize will be controlled after the application of MaisTer power including Polygonum species. If a dose rate of 1,0 L/ha is used it could make sense to add a tank mix partner like Aspect to complete the spectrum against some weeds like Chenopodium album or Polygonum convolvulus.

  8. Spent coffee grounds as air-propelled abrasive grit for weed control

    Science.gov (United States)

    Spent coffee grounds (SCG) represent a significant food waste residue. Value-added uses for this material would be beneficial. Gritty agricultural residues, such as corncob grit, can be employed as abrasive air-propelled agents for organically-compatible postemergence shredding of weed seedlings sel...

  9. Cover crops increase foraging activity of omnivorous predators in seed patches and facilitate weed biological control

    Science.gov (United States)

    Omnivores are important consumers of both weed seeds and insect pests, and habitat provisions like cover crops are suggested to promote their ecosystem services in agricultural systems. However, few studies establish direct links between cover, food, and pest suppression because they are entangled a...

  10. Short-term and long-term effects of weed control and fertilization on growth and wood anatomy of a Populus deltoides clone

    Directory of Open Access Journals (Sweden)

    Silvia Estela Monteoliva

    2015-04-01

    Full Text Available Aims of study: The short- and long-term effects of weed control and fertilization on growth and wood anatomy of 10-y-old Populus deltoides were investigated. Weed control and fertilization usually leads to an increase the growth rate of trees, and consequently, a possible modification in the quality of produced wood. Area of study: We analyzed trees from an experimental plantation in Buenos Aires, Argentina (34° 50’ S Lat; 60° 30’ W Long. Methods: 32 trees from three treatments: mechanical weed control (M, chemical and mechanical weed control (CHM and fertilized plus chemical and mechanical weed control (CHM-F were analyzed. Basal area, fibre morphology, cell wall area and vessel size were measured in the growth ring 1, 3 and 10. Results: differences on wood anatomy among treatments were mainly observed at the third year (short-term effect. Long-term negative effects were not observed. Fertilized trees had greater proportion and quality of wood closer to pith. Research highlights: fibre and vessel differences seen in CHM and CHM-F compared to controls in year 3 could be interpreted as evidence of maturation in cambial development (thicker, longer and wider fibres and greater vessels. The CHM-F treatment had a greater proportion of wood that showed characteristics of more mature wood.

  11. 36 CFR 222.8 - Cooperation in control of estray or unbranded livestock, animal diseases, noxious farm weeds, and...

    Science.gov (United States)

    2010-07-01

    ... estray or unbranded livestock, animal diseases, noxious farm weeds, and use of pesticides. 222.8 Section... unbranded livestock, animal diseases, noxious farm weeds, and use of pesticides. (a) Insofar as it involves... farm weeds. (2) The Animal and Plant Health Inspection Service and other Federal or State agencies and...

  12. Design and Simulation Analysis of Vertical Weed Control Device Between Seedlings in Paddy Field%水田株间立式除草装置的设计

    Institute of Scientific and Technical Information of China (English)

    杨松梅; 王金武; 刘永军; 王金峰; 赵佳乐

    2014-01-01

    Mechanical weed control is the best method to solve serious environmental pollution , weed resistance and other hazards caused by large use of herbicide .As the weeds between seedlings were difficult to control , a kind of vertical intra-row weed control device in paddy field was designed and its structure and working principle were described .Its 3 D model was constructed using PRO/E and kinematics simulation was carried by using ADAMS , obtaining weeding trajecto-ry of weeding spring tooth .The simulation results were analyzed , gainingλ2=1 .65 , k=8 and optimal parameter values , which provides the theoretical basis of the key components for the development of weeding machine for paddy fields .%机械除草是解决除草剂大量使用而造成环境严重污染、杂草抗药性增强等危害的最佳方法。针对株间杂草难以控制的问题,设计了一种水田株间立式除草装置,并对其结构及工作原理进行了阐述。运用 Pro/E 软件建立了三维模型,并通过ADAMS软件对株间立式除草刀盘进行运动学仿真,获得株间立式除草弹齿的除草轨迹。对仿真结果进行分析,得出了最佳速比为1.65、齿数k=8时最接近各参数要求的结论,为水田除草机整机关键部件的研制提供了理论依据。

  13. EFFECTIVENESS OF GLYPHOSATE AND 2.4 D AMIN HERBICIDES TO CONTROL WEEDS UNDER Shorea selanica Bl. PLANTATION IN CARITA TRIAL GARDEN, BANTEN

    Directory of Open Access Journals (Sweden)

    Ari Wibowo

    2007-03-01

    Full Text Available A trial was carried out in Carita, West Java, to identify the effectiveness of Glyphosate and 2.4 D Amin Herbicide to control weeds under Shorea selanica Bl. plantation. The trial was conducted through the application of Glyphosate and 2.4 D Amin Herbicide with dosages of 5, 6, 7, 8 and 9 liter per ha and compared with Glyphosate herbicide 5 liter per ha, manual treatment, and control (no treatment. The result showed that Glyphosate and 2.4 D Amin Herbicide could be used to control weeds in order to maintaining S. selanica Bl. plantation. Minimum dosage of 6 liter/ha was effective to control weeds such as Chromolaena odorata DC, Mikania micrantha Will, Lantana camara L, Imperata cylindrica Beauv., Melastoma malabathricum L, and Boreria latifolia Bl. Furthermore, there was no symptom of poison on S. selanica Bl. plantation after herbicide application with all dosages applied.

  14. Milestone – a selective herbicide for the control of important grasses and broadleaved weeds in winter oilseed rape

    Directory of Open Access Journals (Sweden)

    Zotz, Agnes

    2016-02-01

    Full Text Available MilestoneTM herbicide contains the active substance propyzamide (500 g/L and aminopyralid (5.3 g a.e./L and is formulated as a suspension concentrate (SC. Registration for Milestone for the use in winter oilseed rape was granted in Germany in July 2014. The active substance propyzamide is well known from the product KerbTM FLO (containing 500 g/L propyzamide, suspension concentrate, SC which is widely used in winter oilseed rape (WITTROCK et al., 2008. Aminopyralid is formulated in the commercial product Runway (clopyralid + picloram + aminopyralid. Milestone is applied with a use rate of 1.5 L/ha as a post-emergence herbicide from growth stage BBCH 14 of the crop at the beginning of November until February. Kerb FLO is applied with a use rate of 1.875 L/ha at the same timing. The efficacy of Milestone and Kerb FLO was tested in randomised and replicated plot trials in Germany, France and the United Kingdom. Milestone and Kerb FLO showed comparable and very high control levels against monocotyledonous species such as Alopecurus myosuroides, Apera spica-venti, Bromus species and volunteer cereals. Milestone shows a broader spectrum of activity vs. Kerb FLO against dicotyledonous weeds such as Matricaria chamomilla, Papaver rhoeas and Centaurea cyanus. The use of Milestone in dense crops (as the situation was in autumn 2014 for many areas in Germany shows very high efficacy levels as well. The comparison of various application timings between end of October until beginning of December confirms the application date early November for best results. Milestone controls herbicide-resistant weed populations and can be considered an important part of a resistance management program not only in winter oilseed rape but as a component of an integrated weed management strategy in cropping systems.

  15. Is the validation of chemical weed control in linseed possible within the framework of a minor use procedure?

    Directory of Open Access Journals (Sweden)

    Tümmler, Christine

    2014-02-01

    Full Text Available In 1999 more than 68,000 hectares linseed was cultivated in Brandenburg. Today the production has decreased to 5,000 hectares throughout Germany. Fifty percent of the production sites are still in Brandenburg with its sandy soils. According to §§ 18, 18a PflSchG (1998 the herbicides Callisto and Ciral are approved for the control of annual mono- and dicotyledonous weeds until the end of 2014. Various products have been tested for their herbicidal activity and phytotoxic disturbance of the crop because linseed is hard to grow on many sites without chemical weed control. Until 2008 the herbicide Concert dominated linseed production because of its ability to include a wide range of different weeds through splitting application. The §18, §18a approval for Concert ended because the manufacturer recalled Concert and released Concert SX, a generic equivalent with the same active ingredients. The ingredients thifensulfuron and metsulfuron in Concert SX have been known to cause delayed blooming. In experiments with Concert SX more phytotoxic damage to the linseed crop like growth inhibition and thinning of inventory could be determined at some test sites. Since 2008 for postemergance application only Ciral is available, but insufficient effects on Galium aparine, Polygonum aviculare, Fallopia convolvulus, Viola arvensis, Chenopodium album, and Fumaria officinalis could be detected. Therefore other herbicides e.g. sulfonylurea were given particular attention in the last few years. The experimental results show that only a few of the tested herbicides, due to the phytotoxic disturbance of the linseed crop, can be used in order to widen the range of herbicides following the regulations of Artikel 51 VO 1107/2009.

  16. The Invasive American Weed Parthenium hysterophorus Can Negatively Impact Malaria Control in Africa.

    Directory of Open Access Journals (Sweden)

    Vincent O Nyasembe

    Full Text Available The direct negative effects of invasive plant species on agriculture and biodiversity are well known, but their indirect effects on human health, and particularly their interactions with disease-transmitting vectors, remains poorly explored. This study sought to investigate the impact of the invasive Neotropical weed Parthenium hysterophorus and its toxins on the survival and energy reserves of the malaria vector Anopheles gambiae. In this study, we compared the fitness of An. gambiae fed on three differentially attractive mosquito host plants and their major toxins; the highly aggressive invasive Neotropical weed Parthenium hysterophorus (Asteraceae in East Africa and two other adapted weeds, Ricinus communis (Euphorbiaceae and Bidens pilosa (Asteraceae. Our results showed that female An. gambiae fitness varied with host plants as females survived better and accumulated substantial energy reserves when fed on P. hysterophorus and R. communis compared to B. pilosa. Females tolerated parthenin and 1-phenylhepta-1, 3, 5-triyne, the toxins produced by P. hysterophorus and B. pilosa, respectively, but not ricinine produced by R. communis. Given that invasive plants like P. hysterophorus can suppress or even replace less competitive species that might be less suitable host-plants for arthropod disease vectors, the spread of invasive plants could lead to higher disease transmission. Parthenium hysterophorus represents a possible indirect effect of invasive plants on human health, which underpins the need to include an additional health dimension in risk-analysis modelling for invasive plants.

  17. Weed Research in Mint

    Science.gov (United States)

    Weeds present in peppermint and spearmint reduce mint oil yield and quality. Flumioxazin combinations with clomazone and pendimethalin applied to dormant peppermint controlled prickly lettuce and flixweed without significant injury to the crop. Low rates of flumioxazin and sulfentrazone applied imm...

  18. Green Weeding

    Science.gov (United States)

    Penniman, Sarah; McColl, Lisa

    2008-01-01

    Gone are the days of tiptoeing to the dumpsters with boxes of weeded books in tow. Lots of libraries are now taking advantage of the many low-cost services and solutions that promise to help extend the lives of collection discards. Some of these options can be very profitable. Some create goodwill within the local community. Some may seem more…

  19. Effects of pollutant accumulation by the invasive weed saltcedar (Tamarix ramosissima) on the biological control agent Diorhabda elongata (Coleoptera: Chrysomelidae)

    Energy Technology Data Exchange (ETDEWEB)

    Sorensen, Mary A. [Department of Entomology, University of California, Riverside, CA 92521 (United States)], E-mail: mary.sorensen@ucr.edu; Parker, David R. [Department of Environmental Science, University of California, Riverside, CA 92521 (United States); Trumble, John T. [Department of Entomology, University of California, Riverside, CA 92521 (United States)

    2009-02-15

    Hydroponic greenhouse studies were used to investigate the effect of four anthropogenic pollutants (perchlorate (ClO{sub 4}{sup -}), selenium (Se), manganese (Mn), and hexavalent chromium (Cr (VI))) on the biological control agent Diorhabda elongata Brulle. Contaminant concentrations were quantified for experimental Tamarix ramosissima Ledab. plants and D. elongata beetles. Growth of larvae was significantly reduced by Se contamination, but was not affected by the presence of perchlorate, Mn, or Cr (VI). All of the contaminants were transferred from plants to D. elongata beetles. Only Cr (VI) was accumulated at greater levels in beetles than in their food. Because T. ramosissima grows in disturbed areas, acquires salts readily, and utilizes groundwater, this plant is likely to accumulate anthropogenic pollutants in contaminated areas. This study is one of the first to investigate the potential of an anthropogenic pollutant to influence a weed biological control system. - The presence of Se, but not perchlorate, Mn, or Cr (VI), in foliage of the invasive weed saltcedar was shown to reduce growth of the biological control agent Diorhabda elongata.

  20. Long-term yield effects of establishment method and weed control in willow for short rotation coppice (SRC)

    DEFF Research Database (Denmark)

    Larsen, Søren Ugilt; Jørgensen, Uffe; Kjeldsen, Jens Bonderup

    2014-01-01

    establishment methods; 1) vertical planting of standard 0.2 m cuttings; 2) horizontal planting of 0.1 m billets; 3) horizontal planting of 0.2 m billets; 4) horizontal planting of 1.8 m rods. All establishment methods were combined with mechanical and chemical weed control during the establishment year. Dry......, respectively) and lowest for 0.1 m billets (5.6 Mg ha−1 year−1). No differences were found in 2nd rotation. Over 1st and 2nd rotation, mechanical weed control resulted in significantly lower yield than chemical control when combined with 0.1 m billets. Cuttings and 1.8 m rods were compared over 1st, 2nd, 3rd...... matter (DM) yield was measured over 6 harvest rotations corresponding to 16 years. In 1st rotation, yield differed significantly between establishment methods with highest yield for 1.8 m rods (10.4 Mg ha−1 year−1), intermediate yield for cuttings and 0.2 m billets (8.6 and 8.5 Mg ha−1 year−1...

  1. Linking Farmer Weed Management Behavior with Weed Pressure: More than Just Technology

    NARCIS (Netherlands)

    Riemens, M.M.; Groeneveld, R.M.W.; Kropff, M.J.; Lotz, L.A.P.; Renes, R.J.; Sukkel, W.; Weide, van der R.Y.

    2010-01-01

    Most studies on weed population dynamics in farming systems have focused on the effects of different weed control strategies. Those studies usually assume that farmers, operating within a particular system, have a uniform management style. However, it is likely that weed management decision making

  2. [Effects of weeding methods on weed community and its diversity in a citrus orchard in southwest Zhejiang].

    Science.gov (United States)

    Yao, He-Jin; Jin, Zong-Lai; Yang, Wei-Bin; Zhao, Jian-Hua; Zhang, Fan

    2010-01-01

    By using the research methods of ecological community, the effects of different weed management strategies including chemical weeding, manual weeding, and their combination on the weed community and its diversity in a citrus chard of main orange producing region in Quzhou City, Zhejiang Province were studied from June 2005 to May 2008. In control plots, there were 75 species and 25 families of weeds; after chemical weeding, manual weeding, and their combination, there were 46 species and 17 families, 59 species and 20 families, and 51 species and 18 families of weeds, respectively. The Margalef's species richness index, Shannon's diversity index, and Shannon's evenness index were the lowest after chemical weeding, but the highest after manual weeding, suggesting that chemical weeding had the greatest effects on the weed diversity in the citrus orchard. It was suggested that to sufficiently control the weeds while to maintain the weed diversity in the orchard weeds in southwest Zhejiang, the combination of chemical and manual weeding would be the best management strategy.

  3. Controle de plantas daninhas na cultura do milho com gliricídia em consorciação Weed control in maize crop with gliricidia intercropping

    Directory of Open Access Journals (Sweden)

    B.B. Araújo Jr.

    2012-12-01

    Full Text Available A gliricídia (Gliricidia sepium é leguminosa perene, cultivada para propósitos múltiplos, que apresenta crescimento rápido e várias substâncias com propriedades alelopáticas. Existem indicações de que a consorciação com gliricídia também pode trazer benefícios no controle das plantas daninhas do milho. O objetivo deste trabalho foi avaliar o controle das plantas daninhas no milho (híbrido duplo AG 1051 com gliricídia em consorciação. Utilizou-se o delineamento em blocos completos casualizados, com oito repetições. Os tratamentos consistiram em: cultivo do milho com capinas (duas, aos 20 e 40 dias após a semeadura, sem capinas e em consorciação com a gliricídia. A gliricídia foi semeada a lanço, com 25 sementes m-2, por ocasião da semeadura do milho, entre as fileiras deste. Quinze espécies de plantas daninhas foram catalogadas na área experimental, sendo Commelina benghalensis a mais frequente. Os rendimentos de espigas verdes (empalhadas e despalhadas obtidos com a consorciação foram iguais ou superiores a 85% dos rendimentos obtidos com capinas. Além disso, o rendimento de grãos no consórcio chegou a 80% do rendimento de grãos do milho capinado. Portanto, a consorciação com a gliricídia pode ser uma alternativa viável para as produções de milho verde e de grãos, embora essa consorciação não tenha influenciado a densidade e a biomassa seca das plantas daninhas.Gliricidia (Gliricidia sepium, a perennial leguminous species presenting fast growth and several allelopathic substances, is cultivated for multiple purposes. There are good evidences that gliricidia intercropped with maize efficiently controls weeds. This work aimed to evaluate the use of gliricidia intercropped with maize as a method of weed control in maize (hybrid AG 1051. The experiment was carried out in a randomized complete block design with eight replications. The treatments consisted of: maize cropping with hand-hoeing weed control

  4. Weed species shifts in glyphosate-resistant crops.

    Science.gov (United States)

    Owen, Micheal D K

    2008-04-01

    The adoption of glyphosate-based crop production systems has been one of the most important revolutions in the history of agriculture. Changes in weed communities owing to species that do not respond to current glyphosate-based management tactics are rapidly increasing. Clearly, glyphosate-resistant crops (GRCs) do not influence weeds any more than non-transgenic crops. For most crops, the trait itself is essentially benign in the environment. Rather, the weed control tactics imposed by growers create the ecological selection pressure that ultimately changes the weed communities. This is seen in the adoption of conservation tillage and weed management programs that focus on one herbicide mode of action and have hastened several important weed population shifts. Tillage (disturbance) is one of the primary factors that affect changes in weed communities. The intense selection pressure from herbicide use will result in the evolution of herbicide-resistant weed biotypes or shifts in the relative prominence of one weed species in the weed community. Changes in weed communities are inevitable and an intrinsic consequence of growing crops over time. The glyphosate-based weed management tactics used in GRCs impose the selection pressure that supports weed population shifts. Examples of weed population shifts in GRCs include common waterhemp [Amaranthus tuberculatus (Moq ex DC) JD Sauer], horseweed (Conyza canadensis L), giant ragweed (Ambrosia trifida L) and other relatively new weed problems. Growers have handled these weed population shifts with varying success depending on the crop. Copyright (c) 2008 Society of Chemical Industry.

  5. [Effects of conservation tillage and weed control on soil water and organic carbon contents in winter wheat field].

    Science.gov (United States)

    Han, Hui-Fang; Ning, Tang-Yuan; Li, Zeng-Jia; Tian, Shen-Zhong; Wang, Yu; Zhong, Wei-Lei; Tian, Xin-Xin

    2011-05-01

    Taking a long-term (since 2004) straw-returning winter wheat field as the object, an investigation was made in the wheat growth seasons of 2008-2009 and 2009-2010 to study the effects of different tillage methods (rotary tillage, harrow tillage, no-tillage, subsoil tillage, and conventional tillage) and weed management on the soil water and organic carbon contents. No matter retaining or removing weeds, the weed density under subsoil tillage and no-tillage was much higher than that under rotary tillage, harrow tillage, and conventional tillage. From the jointing to the milking stage of winter wheat, retaining definite amounts of weeds, no matter which tillage method was adopted, could significantly increase the 0-20 cm soil water content, suggesting the soil water conservation effect of retaining weeds. Retaining weeds only increased the soil organic carbon content in 0-20 cm layer at jointing stage. At heading and milking stages, the soil organic carbon contents in 0-20, 20-40, and 40-60 cm layers were lower under weed retaining than under weed removal. Under the conditions of weed removal, the grain yield under subsoil tillage increased significantly, compared with that under the other four tillage methods. Under the conditions of weed retaining, the grain yield was the highest under rotary tillage, and the lowest under conventional tillage.

  6. Dominus: Nematode and pathogen control and improved weed control with fomesafen

    Science.gov (United States)

    Few new chemical fumigants have been developed in recent years. One of the exceptions is a biofumigant with the active ingredient allylisothiocyanate (AITC), registered as the commercial product Dominus® (Isagro, USA). Excellent control of fungal plant pathogens and nematodes has been achieved wit...

  7. 苇田杂草发生原因及防除措施%The Causes and Control Measures of Ashimita Weeds

    Institute of Scientific and Technical Information of China (English)

    王洋

    2014-01-01

    阐述目前盘锦苇田主要杂草的分布概况,分析导致杂草发生与迅速蔓延的主要因素,提出苇田杂草的防除措施和强化苇田管理的对策,为盘锦芦苇产业的持续发展提供科学依据和实用技术。%The paper not only discussed the main distribution of ashimita weeds in Panjin, analyzed the main factors which led to weed occurrence and spread rapidly but also presented the measures of ashimita weeds control and the field management. It provided a scien-tific basis and practical technology for sustainable development of the reed industry in Panjin.

  8. Ornamental and Turf Pest Control for Commercial Applicators: Pest Control of Ornamental Plants; NCR 12, Lawn Diseases in the Midwest; NCR 26, Lawn Weeds and their Control. Manual 89.

    Science.gov (United States)

    Craig, W. S., Comp.; And Others

    This training manual provides information needed to meet the minimum EPA standards for certification as a commercial applicator of pesticides in the ornamental and turf pest control category. The text discusses pest control of ornamental plants, lawn diseases, and lawn weeds and their control. (CS)

  9. Biological control of weeds: research by the United States Department of Agriculture-Agricultural Research Service: selected case studies.

    Science.gov (United States)

    Quimby, Paul C; DeLoach, C Jack; Wineriter, Susan A; Goolsby, John A; Sobhian, Rouhollah; Boyette, C Douglas; Abbas, Hamed K

    2003-01-01

    Research by the USDA-Agricultural Research Service (ARS) on biological control of weeds has been practiced for many years because of its inherent ecological and economic advantages. Today, it is further driven by ARS adherence to Presidential Executive Order 13112 (3 February 1999) on invasive species and to USDA-ARS policy toward developing technology in support of sustainable agriculture with reduced dependence on non-renewable petrochemical resources. This paper reports examples or case studies selected to demonstrate the traditional or classical approach for biological control programs using Old World arthropods against Tamarix spp, Melaleuca quinquenervia (Cav) ST Blake and Galium spurium L/G aparine L, and the augmentative approach with a native plant pathogen against Pueraria lobata Ohwi = P montana. The examples illustrated various conflicts of interest with endangered species and ecological complexities of arthropods with associated microbes such as nematodes.

  10. About the value of species diversity in arable weeds for weed management

    Directory of Open Access Journals (Sweden)

    Gerowitt, Bärbel

    2016-02-01

    Full Text Available Arable weeds accompany arable land use – we define them based on their affiliation to ar able systems. They are adapted to such a degree that most of them cannot exist without arable land use. Weeds are part of the total biodiversity on arable fields, as primary producers they are basic for important functions within the ecosystem. This paper elaborates the relevance of species diversity in arable weeds for their management. Arable systems can be regarded for the number of different methods for preventive and direct weed control which are realized. Historical arable land use is roughly divided into three periods, which differ concerning the diversity of weed management and the occurring diversity in weed species. Obviously divers weed management in arable systems and diversity in weed species depend on each other, this is illustrated with a simple abstract picture. Arable systems, which are characterised by simpleness, favor the domination of few species which ensure an effective use of the resources within the ecosystem. One consequence under continuous pressure of an overused tool in weed management is that the genetic diversity within a dominating weed population is exploited to ensure this resource use. Current herbicides represent this tool – the results are herbicide resistant biotypes within the weed populations. Species diversity in arable weeds as a rationale within arable production can assist to prevent this development.

  11. Variação da competição interespecífica em milho em função do controle de plantas daninhas em faixas Variation of interspecific weed competition in corn as a function of banded weed control

    Directory of Open Access Journals (Sweden)

    A. Merotto Jr.

    2001-08-01

    Full Text Available O controle de plantas daninhas em faixas é mais uma estratégia que pode ser utilizada no manejo integrado de plantas daninhas (MIPD para aumentar a racionalização do uso do ambiente no cultivo de plantas. Os objetivos deste trabalho foram determinar o efeito do controle de plantas daninhas em faixas na linha ou na entrelinha e avaliar suas conseqüências sobre a competição interespecífica na cultura do milho. Os tratamentos constaram do estabelecimento de um gradiente de infestação de Brachiaria plantaginea, obtido com a variação da intensidade do controle em pré-emergência, e do controle de plantas daninhas em pós-emergência realizado em faixas na linha, na entrelinha ou em área total. O controle de plantas daninhas em pós-emergência em faixas não foi suficiente para reduzir os efeitos da competição interespecífica sobre o rendimento de grãos de milho, mesmo em baixas densidades de plantas daninhas. Os prejuízos causados pela presença de plantas daninhas na linha da cultura são duas a três vezes maiores em comparação com a presença destas plantas na entrelinha ou em área total da cultura. O controle de plantas daninhas na linha da cultura necessita de complementação com práticas culturais ou outros métodos de controle destas plantas na entrelinha.Banded weed control is one of the methods used for integrated weed management (IWM to increase the rationalization of environmental use in crop activities management. The aim of this work was to determine the effect of in-and between-row weed control and the effects of weed competition on corn. The treatments consisted in the establishment of a range of Brachiaria plantaginea densities by varying the intensity of weed control in pre-emergence, complemented with post-emergence weed control in-row, between row and broadcast. Banded weed control was not efficient in decreasing weed competition and reducing corn grain yield, even at low weed infestation. In-row weed

  12. Weed control and green ear yield in maize Controle de plantas daninhas e rendimento de espigas verdes de milho

    Directory of Open Access Journals (Sweden)

    P.S.L. Silva

    2004-03-01

    Full Text Available The objective of this work was to evaluate the influence of weeding frequency on cultivar Centralmex green corn yield. Two experiments were conducted in Mossoró-RN (Brazil, with the use of sprinkler irrigation. A random block design with four replicates was used. It was observed that the total number and weight (TW of unhusked green ears, the number and weight of marketable unhusked ears and the number and weight of marketable husked ears were reduced under no weeding treatment. The number timing of weedings did not influence green corn yield, except for one weeding at 60 DAP, which was equivalent to the "no weeding" treatment, for TW. When maize is marketed considering the total number of green ears, higher net income is obtained when one weeding is carried out 45 days after planting.O objetivo deste trabalho foi avaliar as influências da freqüência de capinas sobre o rendimento de milho-verde do cultivar Centralmex. Dois experimentos foram realizados em Mossoró-RN, com irrigação por aspersão. Utilizou-se o delineamento de blocos ao acaso, com quatro repetições. Verificou-se que a ausência de capinas reduz o número e o peso (PT totais de espigas verdes empalhadas, o número e o peso de espigas empalhadas comercializáveis e o número e o peso de espigas despalhadas comercializáveis. O número e a época de realização das capinas não influenciaram o rendimento de milho-verde, exceto uma capina aos 60 DAP, que é equivalente ao tratamento "sem capina", para PT. Quando o milho é comercializado considerando-se o número total de espigas verdes, maior receita líquida é obtida com a realização de uma capina, aos 45 dias após o plantio.

  13. Effect of different doses of post-emergence-applied iodosulfuron on weed control and grain yield of malt barley (Hordeum distichum L., under Mediterranean conditions

    Directory of Open Access Journals (Sweden)

    Barros José Calado

    2016-01-01

    Full Text Available A study was carried out over a two year period (2009/2010 and 2012/2013 on an experimental farm in the Alentejo region (Beja, in southern Portugal where rainfed malt barley (Hordeum distichum L. is sown at the end of autumn or beginning of winter (November- December. The aim of this experiment was to study the efficiency of the herbicide iodosulfuron-methyl-sodium to control post-emergence broadleaved weeds in this cereal crop. The malt barley crop was established using no-till farming. This technology provides the necessary machine bearing capacity of the soil to assure the post-emergence application of herbicides at two different weed development stages. The herbicide iodosulfuron-methyl-sodium was applied at three doses (5.0, 7.5, and 10.0 g a. i. · ha-1 and at two different broadleaved weed development stages (3 to 4 and 6 to 7 pairs of leaves, that also corresponded to two different crop development stages (beginning of tillering and complete tillering. The results indicated that early herbicide application timing provided a significantly higher efficiency for all the applied herbicide doses, but this better weed control was not reflected in a higher crop grain yield. The lack of a higher crop grain yield was probably due to a crop phytotoxicity of the herbicide, when used at an early application timing.

  14. Herbicidas no transplante de mudas de sisal (Agave sisalana perr. Weed control and herbicide selectivity to sisal (Agave sisalana perr.

    Directory of Open Access Journals (Sweden)

    Antonio Luiz de Barros Salgado

    1980-01-01

    Full Text Available Com o objetivo de verificar a eficiência de hebraicas no controle de plantas daninhas e sua seletividade à cultura do sisal, foi instalado, em setembro de 1976, um experimento de campo em solo argiloso, com os seguintes tratamentos (i.a./hectare trifluralin a 0,84 e 0,96kg em pré-plantio com incorporação; alachlor a 2,40 e 3,26kg; metribuzin a 0,70 e 0,84kg; bromacil a 1,60 e 2,40kg; terbacil a 1,60 e 2,40kg; diuron a 2,40 e 3,20kg; simazine a 3,20 e 4,00kg; fluometuron a 1,20 e 1,60kg, todos em pré-emergência; uma testemunha carpida e outra sem capina. Foram feitas avaliações de controle do mato aos 67 e 114 dias e da condição da cultura aos 600 dias após a aplicação. Aos 114 dias, o controle de gramíneas foi acima de 90% pelo trifluralin, bromacil e terbacil, em torno de 80% pelo simazine, e inferior a 75% pelos demais; para dícotiledôneas, o controle foi de 90 a 100% pelo bromacil e terbacil, e de 80 a 85%o pelo simazine. Nenhum dos tratamentos afetou a cultura durante o período considerado, que foi de 600 dias. Aos 550 dias, fez-se avaliação da área coberta por reinfestação do mato, tendo o terbacil controlado ainda 75 e 95% do total, respectivamente, para as doses menor e maior; o trifluralin, 60 e 70% e, os demais, abaixo de 45%. Na avaliação final da cultura, aos 600 dias, foram considerados: população de plantas, número de plantas com perfilhos e condição da cultura. Os tratamentos que realizaram melhor controle do mato apresentaram também os melhores índices de desenvolvimento da cultura, atestando sua seletividade.The weed control with herbicides and its selectivity to sisal were studied on a clay soil field trial. The treatments (in a.i./ha were: 0.84 and 0.96kg of pre-plant incorporated trifluralin; 2.40 and 3.26kg of alachlor; 0.70 and 0.84kg of metribuzin; 1.60 and 2.40kg of bromacil; 1.60 and 2.40kg of terbacil; 2.40 and 3.20k- of diuron; 3.20 and 4.00kg of simazine; 1.20 and 1.60kg of fluometuron

  15. 220 213 Effects of Weeds on the Profitabili

    African Journals Online (AJOL)

    2008-12-02

    Dec 2, 2008 ... Groundnut (Arachis hypogaea) Crops in Mixed Cropping Systems. 1A.T. Yahaya, 1K.M. Baba, 1U. ... outweighed any possible benefit associated with weeds. ..... for weed control such as crop rotation and cover cropping.

  16. Exploring cost-effective maize integrated weed management ...

    African Journals Online (AJOL)

    Exploring cost-effective maize integrated weed management approaches under intensive farming systems. ... Log in or Register to get access to full text downloads. ... Kamuliand Iganga districts with one hand-hoe weeding (1hh) as the control.

  17. IMPORTANCE OF CRITICAL PERIOD OF WEED COMPETITION FOR CROP GROWING

    OpenAIRE

    Marijana Ivanek-Martinčić; Zvonimir Ostojić; Klara Barić

    2010-01-01

    A concept of critical period of weed competition has been introduced for more than 40 years ago. The concept is based on the assumption that weeds are not equally harmful to a crop during the whole season and that there is a period in crop development in which weeds impact on the yield is the biggest. This period is called critical period of weed competition (CPWC), critical period of weed interference, or critical period of weed control. There is a difference in CPWC between crops, but CPWC ...

  18. Weed Interference Affects Dry Bean Yield and Growth

    Directory of Open Access Journals (Sweden)

    Hossein GHAMARI

    2012-08-01

    Full Text Available Dry bean is one of the most important pulse crops in Iran. Field study was conducted in 2011 to evaluate effects of weed competition from a natural flora on growth and yield of dry bean (Phaseolus vulgaris L.. The treatments consisted of weed infestation and weed removal periods (10, 20, 30, 40 and 50 days after crop emergence. Control plots kept weed-infested and weed-free throughout growing season. To assess the weed competition effect on crop characteristics, Richards, Gompertz and logistic equations were fitted to the data. The most abundant weed species were Chenopodium album and Amaranthus retroflexus. Increase in duration of weed interference decreased the stem height of dry bean. At the end of the growing season, dry bean was 20 cm taller in season-long weed-free treatment compared to the season-long weed-infested treatment. As the number of days of weed interference increased, a declining trend of LAI and number of pods was observed. The minimum number of pods was obtained in season-long weed-infested treatment (5.01 pods/plant. Weed interference during the whole growing season, caused a 60% reduction in yield. Considering 5% and 10% acceptable yield lost, the critical period of weed competition was determined from 20 to 68 and 23 to 55 days after planting (DAE, respectively.

  19. Weeds in a Changing Climate: Vulnerabilities, Consequences, and Implications for Future Weed Management.

    Science.gov (United States)

    Ramesh, Kulasekaran; Matloob, Amar; Aslam, Farhena; Florentine, Singarayer K; Chauhan, Bhagirath S

    2017-01-01

    role in developing future management programs for future weed threats. This review has presented a comprehensive discussion of the recent research in this area, and has identified key deficiencies which need further research in crop-weed eco-systems to formulate suitable control measures before the real impacts of climate change set in.

  20. Weeds in a Changing Climate: Vulnerabilities, Consequences, and Implications for Future Weed Management

    Science.gov (United States)

    Ramesh, Kulasekaran; Matloob, Amar; Aslam, Farhena; Florentine, Singarayer K.; Chauhan, Bhagirath S.

    2017-01-01

    role in developing future management programs for future weed threats. This review has presented a comprehensive discussion of the recent research in this area, and has identified key deficiencies which need further research in crop-weed eco-systems to formulate suitable control measures before the real impacts of climate change set in. PMID:28243245

  1. Focus on ecological weed management : what is hindering adoption?

    NARCIS (Netherlands)

    Bastiaans, L.; Paolini, R.; Baumann, D.T.

    2008-01-01

    Despite increased concerns regarding the heavy reliance of many cropping systems on chemical weed control, adoption of ecological weed management practices is only steadily progressing. For this reason, this paper reflects on both the possibilities and limitations of cultural weed control practices.

  2. Onion and weed response to mustard (Sinapis alba) seed meal

    Science.gov (United States)

    Weed control in organic onion production is often difficult and expensive, requiring numerous cultivations and extensive hand-weeding. Onion safety and weed control with mustard seed meal (MSM) derived from Sinapis alba was evaluated in greenhouse and field trials. MSM applied at 110, 220, and 440 g...

  3. Herbicide-resistant weeds: Management strategies and upcoming technologies

    Science.gov (United States)

    Herbicides have contributed to substantial increase in crop yields over the past seven decades. Over reliance on herbicides for weed control has led to rapid evolution of herbicide-resistant (HR) weeds. Increased awareness of herbicide resistance and adoption of diversified weed control tactics by f...

  4. Image-based thresholds for weeds in maize fields

    DEFF Research Database (Denmark)

    Asif, Ali; Streibig, Jens Carl; Christensen, Svend

    2015-01-01

    Recent development of site-specific weed management strategies suggests patch application of herbicides to avoid their excessive use in crops. The estimation of infestation of weeds and control thresholds are important components for taking spray decisions. If weed pressure is below a certain level...... in some parts of the field and if late germinating weeds do not affect yield, it may not be necessary the spray such places from an economic point of view. Consequently, it makes sense to develop weed control thresholds for patch spraying, based on weed cover early in the growing season. In Danish maize...... field experiments conducted from 2010 to 2012, we estimated competitive ability parameters and control thresholds of naturally established weed populations in the context of decision-making for patch spraying. The most frequent weed was Chenopodium album, accompanied by Capsella bursa-pastoris, Cirsium...

  5. Controle de plantas daninhas em soja com doses reduzidas de herbicidas Soybean weed control with reduced rates of herbicides

    Directory of Open Access Journals (Sweden)

    Nilson G. Fleck

    1995-01-01

    . It was obtained Alexandergrass control around 95% for all the treatments, with small but not significant variations among them. Soybean seed yield was equivalent for the hoeing check, haloxyfop-methvl at 90 and 60 g/ha and sethoxydim at 220, 110, and 55+55 g/ha. The additional treatments were equivalents among them, but all surpassed the weeded check, which produced the lowest yield. These results evidence the possibility of using reduced herbicides rates, which may reach yield levels as high as those attained with full rates.

  6. Avaliação de herbicidas no controle de plantas daninhas em mandioquinha-salsa Herbicide efficiency in controlling weeds in peruvian carrot

    Directory of Open Access Journals (Sweden)

    Maria Aparecida Nogueira Sediyama

    2008-12-01

    Full Text Available Avaliou-se a eficiência de herbicidas aplicados em pré e pós-emergência no controle de plantas daninhas e na produção de mandioquinha-salsa na Fazenda Experimental da EPAMIG, em Oratórios (MG, de maio a dezembro de 2002. Utilizou-se o delineamento de blocos casualizados com quatro repetições e 15 tratamentos incluindo duas testemunhas, com e sem capina. Em cada tratamento, foi usado um herbicida em pré e outro em pós-emergência das plantas, aplicados aos três e aos 45 dias após o plantio (DAP respectivamente. A eficiência de controle e a toxidez dos herbicidas foram avaliadas aos 60 DAP e a produção de matéria seca de plantas daninhas aos 60 e 130 DAP. Na colheita, avaliou-se produção de raízes, coroa e parte aérea. A emergência de plantas foi máxima aos 45 DAP e, posteriormente, houve redução no estande, quando se utilizaram os herbicidas atrazine + óleo mineral e oxadiazon, em pós-emergência. Esses herbicidas, apesar de eficientes no controle de plantas daninhas, causaram toxidez à cultura. Na produção de raízes, destacaram-se os tratamentos: atrazine +fluazifop-p-butil; diuron + fluazifop-p-butil; diuron + Oxadiazon; linuron + fluazifop-p-butil; metolachlor + metribuzin + linuron e oxadiazon + diuron, com bom controle de plantas daninhas e rendimentos de raízes comerciais semelhantes ao da testemunha mantida no limpo (8,62 t ha-1.The efficiency of herbicides applied in pre- and post-emergence for weed control in Peruvian carrot production was evaluated at the EPAMIG Experimental Farm, Oratórios, Minas Gerais State, from May to December, 2002. The experiment was arranged in a randomized block design, with four replications and 15 treatments, including two controls (with and without weeding. Pre- and post-emergence herbicides were used in each treatment applied at 3 and 45 days after planting (DAP, respectively. Efficiency and toxicity were evaluated at 60 DAP and weed dry matter yield at 60 and 130 DAP. At

  7. Sistemas de control de malezas en maiz (Zea mays L.: efecto de metodos de control, densidad y distribucion del cultivo Weed control systems in corn: effects of control methods, density and plant distribution

    Directory of Open Access Journals (Sweden)

    G. Martinez

    1982-12-01

    realización de una escarda adicional no mejora significativamente el control de malezas, no afectando tampoco la incidencia de enfermedades, ni el desarrollo del cultivo, por lo cual resulta innecesaria. Las escardas tienen como principal efecto eliminar la interfe rencia presentada por las malezas y si éstas son eliminadas de otra manera, la realización de aquéllas no apareja beneficios significativos.An experiment was conducted at the Research Station of the University of Chapingo (Mexico (2250 m above sea level, average annual rainfall 550 mm( loamy soil, 1,7% O.M., where different cultural practices were combined in order to design a weed control system for corn. The work was done under rainfed conditions and the variables included were: two population densities (44.400 and 66.600 pl/ha, two plant distributions (normal and equidistant and seven weed control methods (cyanazine + alachlor (1,2 + 1,92 kg/ha, atrazine + alachlor (1,2 + 1,44 kg/ha, one cultivation, two cultivations, a weeded check, a weeded check + two cultivations and a weedy check. The main weed species were: pigweed (Amaranthus sp., Lopezia mexicana Jacq., hairy galinsoga (Galin-soga parviflora Cay., Encelia mexicana Mart., Sporobulus poiretti (Roem. et Sch. Hich., and large crabgrass (Digitaria sanguinalis (L. Scop.. The increase in plant population had no effect on the degree of weed control, incidence of diseases and crop growth. The equidistant distribution improved weed control over the normal one, but it also had a nigher incidence of diseases; this, is turn, may have caused the lack of differences in vegetative growth, a lower amount of cobs per ha and the lack of difference in grain yield between the two distributions. Atrazine + alachlor was better than cyanazine + alachlor in terms of weed control, although the difference was statistically observed only for the visual ratings. There were no differences between both chemical treatments in terms of incidence of diseases or their effect on crop

  8. Evaluation of the Upland Weed Control Potentiality of Green Tea Waste-Rice Bran Compost and Its Effect on Spinach Growth

    Directory of Open Access Journals (Sweden)

    M. A. I. Khan

    2007-01-01

    Full Text Available This study evaluated the upland weed control potentiality, germination inhibition ability and growth suppression efficiency of the five combinations of green tea waste rice bran compost (GRC. GRC was prepared by mixing green tea waste and rice bran at five ratios, and allowed to decompose for 5 mo. Application of GRC suppressed weed growth up to 93.4% in number and 95.4% in dry weight in 2004, and 80.7% in number and 73.4% in dry weight of weeds in 2005, as compared with the untreated control (only soil under the greenhouse condition. Among the five combinations of GRC, rice bran alone (RC showed the significantly highest and green tea waste alone (GC showed the lowest weed suppressing activity in both years. The weed control potentiality of GRC was increased by the increase of rice bran percentages in the mixture. The exudates of GRC inhibited the hypocotyl and radicle elongation of lettuce seedlings when examined by the sandwich method. The water extracts of GRC also inhibited the germination and radicle elongation of the test species in the seed germination tests. The growth inhibitory activity of RC was greater than that of GC, and radicle elongation was more sensitive than seed germination and hypocotyl elongation in all bioassays. The inhibitory activity of GRC water extract varied with the test species and was higher for the dicotyledonous species than monocotyledonous species. The inhibitory effect on seed germination and seedling growth increased as the extract concentration increased. The concentration dependent responses of test species to the water extract of GRC indicated that it might contain phytotoxic substances that were responsible for growth inhibition. Moreover, GRC promoted spinach growth significantly compared with the untreated control. These results suggest that the use of 30% green tea waste + 70% rice bran mixture compost (GRC-3 might be useful to control the upland weeds and enhance spinach growth among the five

  9. Weed Control Efficiency of wild Safflower (Carthamus oxyacanthus M. Bieb in Replacement Series Technique of Barley (Hordeum vulgare L. and Common Vetch (Vicia sativa L.

    Directory of Open Access Journals (Sweden)

    abdolreza ahmadi

    2017-01-01

    Full Text Available Introduction In agronomy, natural outlook has been expressed in different forms which stable agriculture is an example. Stable agriculture is ascribed to the authentic management of agricultural resources, which in addition to fulfilling the ever-changing needs of humans, maintains the health of environment and capacity of water and soil resources. Application of herbicides, besides being costly, resulted in the selection of herbicide resistant weed species and has become an environmental contamination factor. However, reduction of herbicide consumption is one of the goals of modern agriculture, with several methods being suggested, including intercropping. In natural conditions of production, environment conservation of weed existence requires cost. One of the important preparations in weed control from the perspective of sustainable agriculture, is using intercropping system. The aim of this study was to determine the role of crop diversity on weed and crop production based on the beneficial effects of intercropping system than pure. Materials and methods In order to study effects of mixed and sole cropping of barley with common vetch on their biologic yield and utilization indices, an experiment was conducted in Agricultural college of the University of Lorestan, during the growing season of 2013-2014 with 24 treatments using the method of rows replacement series technique by the randomized complete block design in a factorial arrangement with three replications. First factor included 6 levels of intercropping: sole cropping of common vetch (100%, 55-45 (Common vetch-barley, 35-65, 45-55, 65-35 and sole cropping of barley and second factor included 4 levels of weed wild safflower, control, 10, 15 and 20 plants per m2. In this experiment WCE, LER and CR were measured. The data were subjected to analysis of variance (ANOVA using Mstat-C computer software. Mean comparisons were performed using Duncan’s multiple range test at two levels of

  10. WEED CONTROL IN GENETICALLY MODIFIED GLYPHOSATE-TOLERANT SOYBEAN MANEJO DE PLANTAS DANINHAS EM SOJA GENETICAMENTE MODIFICADA TOLERANTE AO GLYPHOSATE

    Directory of Open Access Journals (Sweden)

    Júlio Cezar Durigan

    2011-04-01

    Full Text Available The transgenic production systems, as well as conventional systems, require, in addition to chemical control, the adoption of other weed management strategies. This study was developed to evaluate the weed chemical control in glyphosate tolerant soybean, associated to cover crops cultivated in the autumn/winter. The experiment was carried out under field conditions at the FCAV/Unesp, Jaboticabal, São Paulo State, Brazil. A randomized split-plot block design was used, with four replications. St. Lucia Grass (Brachiaria brizantha ‘Marandu’, forage millet (Pennisetum americanum ‘BN2’, and a treatment with spontaneous growth vegetation were evaluated for plots, and, for subplots, the herbicides glyphosate, chlorimuron - ethyl plus lactofen, and fluazifop-p-butyl, in a sequential spraying, and two controls without any application. Grass cover contributed to the chemical control, suppressing weeds, and the single application of 720 g a.e. ha-1 of glyphosate, independently of the cover crop cultivated in the autumn/winter, was sufficient for adequately controlling Acanthospermum hispidum, Alternanthera tenella, Amaranthus sp., Bidens pilosa, Xanthium strumarium, Cenchrus echinatus, Digitaria sp., and Eleusine indica, with results similar to the treatment (chlorimuron-ethyl + lactofen + fluazifop-p-buthyl. When compared to the weeded control, the herbicides did not affect plants height, dry matter of the aerial parts, mass of 100 grains, and grain yield. Soybean plants grown over St. Lucia Grass and forage millet presented a higher height, however, no other feature was influenced by the cover crop.

    KEY-WORDS: Brachiaria brizantha; Pennisetum americanum; no-tillage; Roundup Ready; spontaneous vegetation.

    Os sistemas de produção transgênicos, assim como os

  11. Obsolescence, Weeding, and the Utilization of Space.

    Science.gov (United States)

    Lancaster, F. W.

    1988-01-01

    Suggests an objective approach to weeding library materials and discusses ways of measuring obsolescence and of controlling variables to provide a true picture of aging. Weeding is shown to improve space utilization and the quality of a collection. (5 references) (MES)

  12. Weed management strategies for castor bean crops

    Directory of Open Access Journals (Sweden)

    Augusto Guerreiro Fontoura Costa

    2014-04-01

    Full Text Available Castor bean crops are agriculturally relevant due to the quality and versatility of their oil, both for the chemical industry and for biodiesel production. Proper weed management is important for both the cultivation and the yield of castor bean crops; therefore, the intention of the present work is to review pertinent information regarding weed management, including the studies regarding weed interference periods, chemical controls for use in different crop production systems and herbicide selectivity, for castor bean crops. Weed science research for castor bean crops is scarce. One of the main weed management challenges for castor bean crops is the absence of herbicides registered with the Ministry of Agriculture, Livestock and Food Supply (MALFS. Research for viable herbicides for weed control in castor bean crops should be directed by research and/or rural extension institutions, associations and farmers cooperatives, as well as by manufactures, for the registration of these selective herbicides, which would be primarily used to control eudicotyledons in castor bean crops. New studies involving the integration of weed control methods in castor bean also may increase the efficiency of weed management, for both small farmers using traditional crop methods in the Brazilian Northeast region, as well as for areas with the potential for large scale production, using conservation tillage systems, such as the no-tillage crop production system.

  13. Cover crop-based ecological weed management: exploration and optimization

    NARCIS (Netherlands)

    Kruidhof, H.M.

    2008-01-01

    Keywords: organic farming, ecologically-based weed management, cover crops, green manure, allelopathy, Secale cereale, Brassica napus, Medicago sativa Cover crop-based ecological weed management: exploration and optimization. In organic farming systems, weed control is recognized as one of the mai

  14. CRITICAL PERIOD OF MUNGBEAN (PHASEOLUS RADIATUS L. TO WEED COMPETITION

    Directory of Open Access Journals (Sweden)

    I.H. UTOMO*

    1989-01-01

    Full Text Available A field experiment was conducted to study the critical period of weed control on the crop of mungbean (Phaseolus radiatus L.. The studies were done in the field of BIOTROP Experimental Station with the natural existing weed population. It was found that the critical period of mungbean to weed competition was from 3-6 weeks after planting.

  15. CRITICAL PERIOD OF MUNGBEAN (PHASEOLUS RADIATUS L.) TO WEED COMPETITION

    OpenAIRE

    I.H. UTOMO*

    1989-01-01

    A field experiment was conducted to study the critical period of weed control on the crop of mungbean (Phaseolus radiatus L.). The studies were done in the field of BIOTROP Experimental Station with the natural existing weed population. It was found that the critical period of mungbean to weed competition was from 3-6 weeks after planting.

  16. Cover crop-based ecological weed management: exploration and optimization

    NARCIS (Netherlands)

    Kruidhof, H.M.

    2008-01-01

    Keywords: organic farming, ecologically-based weed management, cover crops, green manure, allelopathy, Secale cereale, Brassica napus, Medicago sativa Cover crop-based ecological weed management: exploration and optimization. In organic farming systems, weed control is recognized as one of the

  17. Transgenic glyphosate-resistant oilseed rape (Brassica napus) as an invasive weed in Argentina: detection, characterization, and control alternatives.

    Science.gov (United States)

    Pandolfo, Claudio E; Presotto, Alejandro; Carbonell, Francisco Torres; Ureta, Soledad; Poverene, Mónica; Cantamutto, Miguel

    2016-12-01

    The presence of glyphosate-resistant oilseed rape populations in Argentina was detected and characterized. The resistant plants were found as weeds in RR soybeans and other fields. The immunological and molecular analysis showed that the accessions presented the GT73 transgenic event. The origin of this event was uncertain, as the cultivation of transgenic oilseed rape cultivars is prohibited in Argentina. This finding might suggest that glyphosate resistance could come from unauthorized transgenic oilseed rape crops cultivated in the country or as seed contaminants in imported oilseed rape cultivars or other seed imports. Experimentation showed that there are alternative herbicides for controlling resistant Brassica napus populations in various situations and crops. AHAS-inhibiting herbicides (imazethapyr, chlorimuron and diclosulam), glufosinate, 2,4-D, fluroxypyr and saflufenacil proved to be very effective in controlling these plants. Herbicides evaluated in this research were employed by farmers in one of the fields invaded with this biotype and monitoring of this field showed no evidence of its presence in the following years.

  18. Control of amphibious weed ipomoea (Ipomoea carnea by utilizing it for the extraction of volatile fatty acids as energy precursors

    Directory of Open Access Journals (Sweden)

    M. Rafiq Kumar

    2015-01-01

    Full Text Available Volatile fatty acids (VFAs, comprising mainly of acetic acid and lesser quantities of propionic and butyric acids, are generated when zoomass or phytomass is acted upon by acidogenic and acetogenic microorganisms. VFAs can be utilized by methanogens under anaerobic conditions to generate flammable methane–carbon dioxide mixtures known as ‘biogas’. Acting on the premise that this manner of VFA utilization for generating relatively clean energy can be easily accomplished in a controlled fashion in conventional biogas plants as well as higher-rate anaerobic digesters, we have carried out studies aimed to generate VFAs from the pernicious weed ipomoea (Ipomoea carnea. The VFA extraction was accomplished by a simple yet effective technology, appropriate for use even by laypersons. For this acid-phase reactors were set, to which measured quantities of ipomoea leaves were charged along with water inoculated with cow dung. The reactors were stirred intermittently. It was found that VFA production started within hours of the mixing of the reactants and peaked by the 10th or 11th day in all the reactors, effecting a conversion of over 10% of the biomass into VFAs. The reactor performance had good reproducibility and the process appeared easily controllable, frugal and robust.

  19. Evaluation of Broadleaf Weeds Control with Selectivity of Post-Emergence Herbicides in Sugar Beet (Beta vulgaris L.

    Directory of Open Access Journals (Sweden)

    Ali Asghar CHITBAND

    2014-12-01

    Full Text Available The reduction of herbicide applications is a main research priority in recent years. In order to study the effect of individual post-emergence application of sugar beet broad-leaf herbicides at four to six true-leaf stage of weeds, experiments were conducted during 2013. Treatments included untreated control and several rates of desmedipham + phenmedipham + ethofumesate, chloridazon and clopyralid on Portulaca oleracea, Solanum nigrum, Amaranthus retroflexus and Chenopodium album. A completely randomized layout with three replications was used for each herbicide. Three weeks after spraying (WAS, plants were harvested and measured their dry weight. These herbicides were more effective to control Portulaca oleracea than other weeds, thereupon minimum dose required for a satisfactory efficacy of 90% reduction of Portulaca oleracea aboveground dry matter (ED90 were 299.22, 1138.31 and 129.44 g a.i ha-1 of desmedipham + phenmedipham + ethofumesate, chloridazon and clopyralid, respectively. Solanum nigrum was more affected by clopyralid application (132.40 g a.i ha-1, and did not make significant difference in Portulaca oleracea. Chloridazon had lower effect for control of Chenopodium album due to existence of powdery covering on abaxial side of the leaves. Biomass ED50 or ED90, based on log-logistic dose–response curves, for Chenopodium album was considerably higher than other species. These results showed that tank mixtures with other herbicides may be required for satisfactory weed control and reduction in applied herbicides doses.

  20. Evaluation of Broadleaf Weeds Control with Selectivity of Post-Emergence Herbicides in Sugar Beet (Beta vulgaris L.)

    OpenAIRE

    Ali Asghar CHITBAND; Ghorbani, Reza; Mohammad Hassan RASHED MOHASSEL; Majid ABBASPOOR; Abbasi, Rahmat

    2014-01-01

    The reduction of herbicide applications is a main research priority in recent years. In order to study the effect of individual post-emergence application of sugar beet broad-leaf herbicides at four to six true-leaf stage of weeds, experiments were conducted during 2013. Treatments included untreated control and several rates of desmedipham + phenmedipham + ethofumesate, chloridazon and clopyralid on Portulaca oleracea, Solanum nigrum, Amaranthus retroflexus and Chenopodium album. A completel...

  1. 杂草抗药性及其治理策略研究进展%Research Progress on Weed Resistance to Herbicides and Control Methods

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    The mechanisms and factors that influence the evolution of herbicide resistance in weeds are reviewed along with the weed control practices available for the control of herbicide -resistant weeds.Weed resistance to herbicides can be of two types,namely target -site resistance that includes the alteration of the site of action,gene amplification and over-expression,and non -target -site resistance that includes enhancement of metabolic detoxification,limited uptake and translocation,and compartmentalization.The evolution of weed resistance is influenced by many factors,such as resistance mutation frequency,herbicide selective pressure,weed fitness and weed seed bank life.Additionally,gene mutation and genetic characteristics are directly related to its evolution.It is advisable to investigate and identify resistant weeds in fields regularly,apply herbicides properly (with rotation or mixture of active ingredients),and to integrate agronomic man-agement practices to prevent evolution of weed resistance to herbicides in the future.Additionally,fundamental research on allelopathy in plants should be emphasized for providing theoretical bases for developing safer herbicides.%综述了杂草抗药性产生机理、杂草抗药性演化影响因素,并对其治理途径进行阐述,为杂草抗药性治理提供参考。除草剂抗药机制分为靶标抗性、非靶标抗性,其中靶标抗性包括除草剂作用位点改变、基因倍增及过量表达;非靶标抗性主要包括代谢解毒能力增强、屏蔽作用或与作用位点的隔离作用等。杂草抗药性演化受多种因素共同影响,不仅包括抗药性突变频率、除草剂选择压、杂草适合度及杂草种子库寿命四大因素,还与基因突变和遗传特征直接相关。在未来的杂草治理中,要经常进行田间杂草调查与鉴定,正确使用除草剂(交替使用、混用),并辅以合理的农艺管理措施来减缓杂草抗药性的演化速

  2. Weed biocontrol in landscape restoration

    Science.gov (United States)

    Weed biological control programs in natural areas are often undertaken with the goal of restoring native plant communities and/or ecosystem services to a pre-invasion level. These objectives may be achieved in some areas with biological control alone; however, in other sites integration of biologica...

  3. Control Effects of Two-Batch-Duck Raising with Rice Framing on Rice Diseases, Insect Pests and Weeds in Paddy Field

    Directory of Open Access Journals (Sweden)

    Kai-ming Liang

    2012-10-01

    Full Text Available Rice-duck farming system is one of the means of organic rice farming, in which the weeds, diseases and insects could be effectively controlled with minimal or no pesticide and herbicide application. Whereas in conventional rice-duck farming system the controlling effect on diseases, insect pests and weeds was slowly disappeared after the rice heading stage at which ducks were driven out of the paddy field. To fill up the blank period of pasture activities of ducks, this study put forward two new rice-duck farming systems innovated from the conventional rice-duck farming system, in these new systems, two batches of ducks were raised with rice within one rice planting season. The results revealed that the overall controlling effect of ducks on rice diseases, insect pest and weeds was significantly enhanced in the two new rice-duck farming systems without agrochemicals application. It might be suggested that these two new systems have potential application as biocontrol agent for the organic rice agriculture.

  4. Marijuana (Weed, Pot) Facts

    Science.gov (United States)

    ... That People Abuse » Marijuana (Weed, Pot) Facts Marijuana (Weed, Pot) Facts Listen Marijuana is a green, brown, or gray mix of dried, shredded leaves and flowers from the marijuana plant. Marijuana can be rolled up and smoked ...

  5. Weed seed production, crop planting pattern, and mechanical weeding in wheat

    NARCIS (Netherlands)

    Mertens, S.K.; Jansen, J.

    2002-01-01

    Experiments were carried out to investigate weed seed production in widely spaced spring wheat crops that received aggressive mechanical weed control (hoeing and harrowing) compared with that in narrowly spaced crops receiving less aggressive mechanical control (harrowing only). Three species (wild

  6. Research Progress on Weed-controlling by Using Allelochemicals%利用化感物质防除杂草研究进展

    Institute of Scientific and Technical Information of China (English)

    赵强; 董晓宁; 井伟龙; 赵海福

    2012-01-01

    该文阐述了化感作用的作用机理,国内外植物化感抑草的研究现状,进而指出了植物化感作用在抑制杂草方面的优越性及存在的问题,同时对其未来的发展进行了展望.%By elaborating the mechanism of action of allelopathy and the research status of weed-controlling of allelopathy at home and abroad,further pointing out superiority and existing problems of allelopathy in the management of weeds,at the same time looking into the future.

  7. Crop–weed competition

    DEFF Research Database (Denmark)

    Gallandt, Eric R.; Weiner, Jacob

    2015-01-01

    on crops. Longer term management of crop–weed competition can be achieved through crop rotations, specifically crop sequences that reduce the weed seed bank, and therefore seedling density, and prevent proliferation of perennial weeds. Key ConceptsKey Concepts * Plant growth requires sunlight, water...

  8. Horny Goat Weed

    Science.gov (United States)

    Horny goat weed is an herb. The leaves are used to make medicine. As many as 15 horny goat weed species are known as “yin yang huo” in Chinese medicine. Horny goat weed is used for weak back and knees, joint ...

  9. Occurrence, genetic control and evolution of non-target-site based resistance to herbicides inhibiting acetolactate synthase (ALS) in the dicot weed Papaver rhoeas.

    Science.gov (United States)

    Scarabel, Laura; Pernin, Fanny; Délye, Christophe

    2015-09-01

    Non-target-site resistance (NTSR) to herbicides is a major issue for the chemical control of weeds. Whilst predominant in grass weeds, NTSR remains largely uninvestigated in dicot weeds. We investigated the occurrence, inheritance and genetic control of NTSR to acetolactate synthase (ALS) inhibitors in Papaver rhoeas (corn poppy) using progenies from plants with potential NTSR to the imidazolinone herbicide imazamox. NTSR to imazamox was inherited from parents over two successive generations. NTSR to tritosulfuron (a sulfonylurea) was observed in F1 generations and inherited in F2 generations. NTSR to florasulam (a triazolopyrimidine) emerged in F2 generations. Our findings suggest NTSR was polygenic and gradually built-up by accumulation over generations of loci with moderate individual effects in single plants. We also demonstrated that ALS alleles conferring herbicide resistance can co-exist with NTSR loci in P. rhoeas plants. Previous research focussed on TSR in P. rhoeas, which most likely caused underestimation of NTSR significance in this species. This may also apply to other dicot species. From our data, resistance to ALS inhibitors in P. rhoeas appears complex, and involves well-known mutant ALS alleles and a set of unknown NTSR loci that confer resistance to ALS inhibitors from different chemical families.

  10. The Evaluation and the Comparison of the Effect of Mechanical Weeding Systems on Rice Weed

    Directory of Open Access Journals (Sweden)

    Fazlollah Eskandari Cherati

    2012-08-01

    Full Text Available In order to study the influence of different methods of controlling weeds such as mechanical weeding and mechanical weeder efficiency analysis in mechanical cultivation conditions, in farming year of 2011 an experiment was done in a farm in coupling and development of technology center in Haraz, Iran. The treatments consisted of (I control treatment: where no weeding was done, (II use of mechanical weeding without engine and (III power mechanical weeding. Results showed that experimental treatments had significantly different effects (p = 0.05 on yield traits and number of filled grains per panicle, while treatments had the significant effects on grain weight and dry weight of weeds in the first, second and third weeding methods at 1% of confidence level. Treatment (II had its most significant effect on number of filled grains per panicle and yield performance standpoint, which was 3705.97 kg/ha in its highest peak. Treatment (III was ranked as second influential with 3559.8 kg/ha. In addition, under (I treatments, 2364.73 kg/ha of yield produced. The minimum dry weights of weeds in all weeding methods were related to the treatment (II, (III and (I, respectively. The correlation coefficient analysis showed that total yield had a significant positive correlation with the panicle grain yield per plant (r = 0.55* and the number of grains/panicle (r = 0.57* and the number of filled grains (r = 0.63*. Total rice yield also had negative correlation of r = -0.64* with weed dry weight at second weed sampling time (17 DAT. The weed dry weight at third and fourth sampling times (24 and 40 DAT had negative correlations of -0.65** and r = -0.61* with rice yield, respectively.

  11. An ultrasonic system for weed detection in cereal crops.

    Science.gov (United States)

    Andújar, Dionisio; Weis, Martin; Gerhards, Roland

    2012-12-13

    assessed by discriminant analysis. The ultrasonic readings permitted the separation between weed infested zones and non-infested areas with up to 92.8% of success. This system will potentially reduce the cost of weed detection and offers an opportunity to its use in non-selective methods for weed control.

  12. An Ultrasonic System for Weed Detection in Cereal Crops

    Directory of Open Access Journals (Sweden)

    Dionisio Andújar

    2012-12-01

    discrimination were assessed by discriminant analysis. The ultrasonic readings permitted the separation between weed infested zones and non-infested areas with up to 92.8% of success. This system will potentially reduce the cost of weed detection and offers an opportunity to its use in non-selective methods for weed control.

  13. GWN-3189 B – A new selective herbicide based on Triallate for control of herbicide resistant grass weed in cereals

    Directory of Open Access Journals (Sweden)

    Mühlschlegel, Friedrich

    2014-02-01

    Full Text Available With substantial work on the formulation, Gowan offers a new herbicide (GWN-3189 B based on Triallate for use on winter wheat, winter barley, winter rye, winter triticale and spring barley. GWN-3189B will be applied from pre-emergence to early post-emergence of the crop and offers a broad spectrum against grass-weeds. GWN-3189 B is selective on all cereal species. As soil herbicide GWN-3189 B offers interesting alternatives in grass-weed resistance management. The efficacy on grass weed, especially on Alopecurus myosuroides (blackgrass, Apera spica venti (silky bentgrass and Lolium multiflorum (italian ryegrass is demonstrated with results of field trials performed in France, Great Britain and Germany.

  14. Weed supression by smother crops and selective herbicides

    Directory of Open Access Journals (Sweden)

    Severino Francisco José

    2004-01-01

    Full Text Available Using a smother crop is thought to suppress weed density and to add other beneficial effects in sustainable agricultural systems. Weed suppression ought to be considered an essential component of integrated weed management. However, very little is known about the effects of green manure plants on weeds. This study evaluated the influence of three green manure species on weed suppression and selectivity of herbicides. A field experiment was designed to determine the effect of the green manure species Crotalaria juncea, Arachis pintoi and pigeon pea on the weeds Brachiaria decumbens, guineagrass and hairy beggarticks, and on the natural weed infestation in the inter rows area of an avocado orchard. The weed species were suppressed differently by each green manure species. Soil samples collected from the field experiment presented a residual effect, of at least 30 d, in suppressing weed seed bank recruitment; this residual effect was caused by the residues of the green manure present in the soil. When the green manure was incorporated into the top 5 cm of soil or left on the surface, in a greenhouse experiment, the emergence of weed seeds was significantly inhibited, depending on the species, and on the amount and depth of green manure incorporation. Greenhouse experiments indicate that pre-emergence herbicides cause lower phytotoxicity than post-emergence Arachis pintoi. Smother crops using green manure species, when well established in an area, provide additional weed control to the cropping system and are effective and valuable tools in integrated weed management.

  15. 杂草科学管理——理论基础与实施途径%Scientific Management of Weed:Theory and Implementation

    Institute of Scientific and Technical Information of China (English)

    涂修亮; 陈英明

    2002-01-01

    Scientific management of weeds is theoretically based on ecology.The implementation methods inclade:Intensifying the weed biology and ecology research, especially those of the heavy weeds;Intensifying the research of developing competition between the crop and the weed;Utilizing a allelopathy the gene engineering and breeding against the weeds;Utilizing allelopathy between the crop and the weed, and utilizing biological and agricultural measurements to control the weeds.

  16. 苏州市麦田草害现状及防除对策%Current Status and Control Strategies of Weeds in Wheat Field of Suzhou City

    Institute of Scientific and Technical Information of China (English)

    张国彪; 沈晴

    2014-01-01

    加重江苏省苏州市麦田杂草发生的原因包括免耕栽培的推广、稻草全量还田、草相变化、除草剂使用不科学等。要实现控草目标,必须坚持综合治理,立足“一封一杀”的化除策略并科学把好麦田化除技术关。%Weed problems in wheat field of Suzhou City have become more serious in association with changes in the cul -tural practices , including the promotion of no -tillage cultivation , leaving all the straw in the field from rotational rice crop, weed population shifts , and improper use of herbicides .For effective weed control , farmers should adhere to inte-grated practices based on prevention and management , including the judicious use of chemical methods available in wheat .

  17. INTEGRATION OF MECHANICAL AND CULTURAL CONTROL TREATMENTS TO MANAGE INVASIVE SHRUB Chromolaena odorata AND OTHER WEEDS UNDER DROUGHT CONDITIONS IN PASTURE AREA

    Directory of Open Access Journals (Sweden)

    M. Rusdy

    2013-03-01

    Full Text Available A field experiment was conducted on Chromolaena odorata dominated pasture with the objectives of evaluating efficacy of integrated of mechanical and cultural control on weed suppression and determining botanical composition of plant species after treatment started. The treatments were, T1 slashing of Chromolaena every month, T2 digging up of Chromolanea, and exposed to dry (mulching, T3 digging up of Chromolaena followed by burning, T4 digging up of Chromolaena followed by burning and sowing with Centrosema pubescens and T5 digging up of Chromolaena followed by burning and planting with Brachiaria decumbens. Results of experiment showed that under drought conditions, digging up Chromolaena was very effective in suppressing regrowth of Chromolaena but it was not effective to other weeds. Among treatments, digging out of Chromolaena followed by burning and planting with Brachiaria decumbens was the most effective and slashing of Chromolaena every month was the least effective in suppressing weeds. Botanical composition was shifted with treatments. Stachytarpheta jamaicensis and Chromolaena were the dominant species in monthly slashed Chromolaena plots, Stachytarpheta and Calopogonium muconoides were the dominant species in mulched plots while Mimosa pudica, Brachiaria and Centrosema were the dominant species in burnt plots.

  18. INTEGRATION OF MECHANICAL AND CULTURAL CONTROL TREATMENTS TO MANAGE INVASIVE SHRUB Chromolaena odorata AND OTHER WEEDS UNDER DROUGHT CONDITIONS IN PASTURE AREA

    Directory of Open Access Journals (Sweden)

    M. Rusdy

    2014-10-01

    Full Text Available A field experiment was conducted on Chromolaena odorata dominated pasture with the objectivesof evaluating efficacy of integrated of mechanical and cultural control on weed suppression anddetermining botanical composition of plant species after treatment started. The treatments were, T1slashing of Chromolaena every month, T2 digging up of Chromolanea, and exposed to dry (mulching,T3 digging up of Chromolaena followed by burning, T4 digging up of Chromolaena followed byburning and sowing with Centrosema pubescens and T5 digging up of Chromolaena followed byburning and planting with Brachiaria decumbens. Results of experiment showed that under droughtconditions, digging up Chromolaena was very effective in suppressing regrowth of Chromolaena but itwas not effective to other weeds. Among treatments, digging out of Chromolaena followed by burningand planting with Brachiaria decumbens was the most effective and slashing of Chromolaena everymonth was the least effective in suppressing weeds. Botanical composition was shifted with treatments.Stachytarpheta jamaicensis and Chromolaena were the dominant species in monthly slashedChromolaena plots, Stachytarpheta and Calopogonium muconoides were the dominant species inmulched plots while Mimosa pudica, Brachiaria and Centrosema were the dominant species in burntplots.

  19. Qualitative suggestions about chemical weed control of poplar in the nursery and possible improvement on the basis of experimental trials over fifteen years

    Directory of Open Access Journals (Sweden)

    Gennaro M

    2009-06-01

    Full Text Available In this work the results of over fifteen years of experimentation are summarized, concerning the possibility of use of herbicides included in several chemical classes and with various mechanisms of action on poplar clones of different species, European and North American. The active ingredients were tested mainly singly or in commercial mixtures as well, applied before emergence (interpreted here as sprout of poplar cuttings not yet occurred and before weed infestation or after emergence (interpreted here as cuttings with sprouts 20-25 cm long and after weed colonisation. Almost 50% of the 43 tested formulations has proved to be unserviceable in poplar nursery because of the hard damage induced on plantlets, i.e. dicotyledonicides and those with a wide action range, especially applied after emergence. It was the case of acetolactate synthase inhibitors and synthetic auxins. About 25% of formulations has proved to be utilizable with limited risks and 20% without risk. After emergence, the lowest damage was caused by graminicide compounds included in the class of acetyl-CoA carboxylase inhibitors (e.g. diclofop-methyl, cycloxydim; before emergence, very good applicative opportunities were showed by microtubule assembly inhibitors, especially propyzamide, and the cellulose synthesis inhibitor isoxaben. Among the herbicides utilizable with some risk after emergence, the photosynthesis inhibitors pyridate and phenmedipham (singly or in mixture were interesting since they are the only ones that allow the control of broad-leaved weeds in the presence of herbaceous poplar shoots. Before emergence, flufenacet and isoxaflutole were remarkable as well, the latter being active versus hardly limited weeds. In summary, besides the two aforesaid compounds, the graminicide cycloxydim and - more cautiously - clodinafop and propaquizafop may be hopefully introduced in poplar nurseries after emergence, in association with the wide action range mixture of

  20. Extracts from Field Margin Weeds Provide Economically Viable and Environmentally Benign Pest Control Compared to Synthetic Pesticides.

    Science.gov (United States)

    Mkenda, Prisila; Mwanauta, Regina; Stevenson, Philip C; Ndakidemi, Patrick; Mtei, Kelvin; Belmain, Steven R

    2015-01-01

    Plants with pesticidal properties have been investigated for decades as alternatives to synthetics, but most progress has been shown in the laboratory. Consequently, research on pesticidal plants is failing to address gaps in our knowledge that constrain their uptake. Some of these gaps are their evaluation of their efficacy under field conditions, their economic viability and impact on beneficial organisms. Extracts made from four abundant weed species found in northern Tanzania, Tithonia diversifolia, Tephrosia vogelii, Vernonia amygdalina and Lippia javanica offered effective control of key pest species on common bean plants (Phaseolus vulgaris) that was comparable to the pyrethroid synthetic, Karate. The plant pesticide treatments had significantly lower effects on natural enemies (lady beetles and spiders). Plant pesticide treatments were more cost effective to use than the synthetic pesticide where the marginal rate of return for the synthetic was no different from the untreated control, around 4USD/ha, compared to a rate of return of around 5.50USD/ha for plant pesticide treatments. Chemical analysis confirmed the presence of known insecticidal compounds in water extracts of T. vogelii (the rotenoid deguelin) and T. diversifolia (the sesquiterpene lactone tagitinin A). Sesquiterpene lactones and the saponin vernonioside C were also identified in organic extracts of V. amygdalina but only the saponin was recorded in water extracts which are similar to those used in the field trial. Pesticidal plants were better able to facilitate ecosystem services whilst effectively managing pests. The labour costs of collecting and processing abundant plants near farm land were less than the cost of purchasing synthetic pesticides.

  1. Extracts from Field Margin Weeds Provide Economically Viable and Environmentally Benign Pest Control Compared to Synthetic Pesticides.

    Directory of Open Access Journals (Sweden)

    Prisila Mkenda

    Full Text Available Plants with pesticidal properties have been investigated for decades as alternatives to synthetics, but most progress has been shown in the laboratory. Consequently, research on pesticidal plants is failing to address gaps in our knowledge that constrain their uptake. Some of these gaps are their evaluation of their efficacy under field conditions, their economic viability and impact on beneficial organisms. Extracts made from four abundant weed species found in northern Tanzania, Tithonia diversifolia, Tephrosia vogelii, Vernonia amygdalina and Lippia javanica offered effective control of key pest species on common bean plants (Phaseolus vulgaris that was comparable to the pyrethroid synthetic, Karate. The plant pesticide treatments had significantly lower effects on natural enemies (lady beetles and spiders. Plant pesticide treatments were more cost effective to use than the synthetic pesticide where the marginal rate of return for the synthetic was no different from the untreated control, around 4USD/ha, compared to a rate of return of around 5.50USD/ha for plant pesticide treatments. Chemical analysis confirmed the presence of known insecticidal compounds in water extracts of T. vogelii (the rotenoid deguelin and T. diversifolia (the sesquiterpene lactone tagitinin A. Sesquiterpene lactones and the saponin vernonioside C were also identified in organic extracts of V. amygdalina but only the saponin was recorded in water extracts which are similar to those used in the field trial. Pesticidal plants were better able to facilitate ecosystem services whilst effectively managing pests. The labour costs of collecting and processing abundant plants near farm land were less than the cost of purchasing synthetic pesticides.

  2. Kinematics Analysis and Experimental Study on Grid Inter-row Weed Control Device for Paddy Field%栅条式水田行间除草装置运动学分析与试验研究

    Institute of Scientific and Technical Information of China (English)

    刘永军; 王金武; 陶桂香; 张春凤

    2015-01-01

    为解决化学药剂控制水田杂草所带来的环境污染及杂草抗药性增强等危害,设计了一种栅条式水田行间除草装置。同时,对其工作原理进行了阐述,通过运动学分析,推导了栅条的运动轨迹方程,并在试验台上进行试验研究。试验结果表明,该装置可一次性完成对杂草的压、翻、埋等作业,且在栅条个数为10个、栅条宽度为30 mm、除草深度为50 mm时,除草效果最佳,除草率可达81%,满足水田作业除草性能的要求。%To solve the problems of environmental pollution , increasement of weed resistance brought by heavily using herbicide to control weed for paddy field , a grid inter-row weed control device for paddy field was designed and its kine-matics was analyzed ,obtaining the kinematic trajectory equation .Grid, which made weeds pressed , turned and buried in the soil in the process of weeding , is the key part of the device , the results of test in soil bin showed that when the num-ber of grid was 10, the width of grid was 25 mm and weeding depth was 50mm, the effect of weed control was best , and weeding rate could reach 81%.

  3. Controle de plantas daninhas em milho em função de quantidades de palha de nabo forrageiro Weed control in corn as a function of amount of turnip crop residue

    Directory of Open Access Journals (Sweden)

    M.A. Rizzardi

    2006-06-01

    Full Text Available Objetivou-se com este experimento avaliar a influência da quantidade de palha de nabo forrageiro (Raphanus sativus var. oleiferus no controle de plantas daninhas em milho. O delineamento experimental foi o de parcelas subdivididas, em blocos casualizados, com quatro repetições. Os tratamentos constaram das quantidades de 0, 6 e 9 t ha-1 de palha de nabo forrageiro, além do pousio, dispostas na parcela principal e, ainda, de seis momentos de controle de plantas daninhas (milho com 1, 2, 4, 5, 6 e 7 folhas, mais duas testemunhas (sem a presença de plantas daninhas e sem o controle destas, dispostos nas subparcelas. Houve interação de quantidades de palha e momentos de controle em relação ao grau de controle de plantas daninhas; o melhor momento ocorreu entre os estádios de duas a quatro folhas do milho. Na ausência de controle químico, o rendimento de grãos de milho foi superior no tratamento com 9 t ha-1 de palha de nabo forrageiro. O controle químico não proporcionou aumento significativo no rendimento de grãos do milho quando a quantidade de palha de nabo forrageiro foi de 9 t ha-1.The objective of this study was to evaluate the effect of the amount of turnip (Raphanus sativus var. oleiferus crop residue on weed control in corn. The experimental design was a split-plot, in randomized blocks, with four replications. The treatments tested were 0, 6, and 9 t ha-1 of turnip crop residues, fallow period (the amount of residues was equivalent to the amount of natural vegetation residues, arranged as main plots, and six weed control periods (corn plants with 1, 2, 4, 5, 6, and 7 developed leaves, besides two controls (one without weeds and another without weed control, arranged as subplots. Interactions occurred between residue amounts and control periods in relation to the degree of weed control. The best control period was achieved when the corn plants presented from 2 to 4 developed leaves. Corn grain yield was higher in the control

  4. Análise de crescimento em amendoinzeiro (Arachis hypogaea L. submetido à matocompetição Analysis of peanut growth under a weed control

    Directory of Open Access Journals (Sweden)

    Luiz Mauro Barbosa

    1995-07-01

    Full Text Available Foram verificados os efeitos de diferentes períodos de controle e convivência de plantas daninhas (0; 14; 28; 42; 56; 70; 84 e 98 dias na cultura do amendoinzeiro (Arachis hypogaea L. em Moji-Guaçu (SP. As principais espécies invasoras da área experimental foram: Acanthospermum australe (Loef. O. Kuntz, Waltheria indica L., Borreria alata DC., Richardia scabra L., Rhynchelytrum repens (Nees Stapf. et Hubb. e Diodia teres Walt. De maneira geral, durante quase todo o ciclo, a espécie de maior importância relativa foi A. australe, sendo suplantada por outras espécies apenas na colheita, quando já estava encerrando seu ciclo de desenvolvimento. O período inicial de controle das plantas daninhas, além de reduzir a densidade da comunidade infestante, diminuiu sua riqueza em espécies e alterou a importância relativa das populações. A matocompetição resultou na redução do crescimento do amendoinzeiro, principalmente a partir de 42 dias de convivência, afetando a altura das plantas, a área foliar, o índice de área foliar e o acúmulo epígeo de matéria seca. Não foram afetados os números de ramos e de folíolos por planta, nem a qualidade dos grãos e o vigor das sementes do amendoim. A produção de frutos foi reduzida ao redor de 31,5% em decorrência da interferência das plantas daninhas. O período total de prevenção da interferência na produção foi de 14 dias e o período anterior à interferência foi de 70 dias.Effects of different periods (0-14-28-42-56-70-84 and 98 days of weed control in peanut plants (Arachis hypogaea L. were studied in Moji-Guaçu region (State of São Paulo. The main weed species in the experimental area were: Acanthospermum australe (Loef. O. Kuntz, Waltheria indica L.; Borreria alata D.C.; Richardia scabra L.; Rhynchelytrum repens (Ness Stapf. et Hubb and Diodia teres Walt. During the whole peanut life cycle, except at harvest time, the most important weed species was A. australe. The

  5. Utilization of an introduced weed biological control agent by a native parasitoid

    Science.gov (United States)

    A native parasitoid, Kalopolynema ema (Schauff and Grissell) (Hymenoptera, Mymaridae), that usually parasitizes the eggs of Megamelus davisi VanDuzee (Hemiptera, Delphacidae), has begun utilizing a new host, Megamelus scutellaris (Berg) (Hemiptera, Delphacidae), the introduced biological control age...

  6. Cover crop management practices-implications for early season weed control in conservation tillage corn cotton rotation

    Science.gov (United States)

    Use of the winter cover crops is an integral component of the conservation systems in corn (Zea mays L.) and cotton (Gossypium hirsutum L.). A field experiment was initiated in 2004 to evaluate weed suppression provided by winter cover crops in a conservation tillage corn and cotton rotation. Rotati...

  7. Biological Control of the weed hemp sesbania (Sesbania exaltata) in rice (Oryza sativa) by the fungus Myrothecium verrucaria

    Science.gov (United States)

    In greenhouse and field experiments, a mycelial formulation of the fungus Myrothecium verrucaria (IMI 361690; henceforth designated MV) containing 0.20% Silwet L-77 surfactant exhibited high bioherbicidal efficacy against the problematic weed hemp sesbania. High infection and mortality (100%) of he...

  8. Effect of new auxin herbicide formulations on control of herbicide resistant weeds and on microbial activities in the rhizosphere

    Science.gov (United States)

    Widespread distribution of glyphosate-resistant weeds in soybean-growing areas across Mississippi has economically affected soybean planting and follow-up crop management operations. New multiple herbicide-resistant crop (including soybean) technologies with associated formulations will soon be comm...

  9. Image analysis as a non-destructive method to assess regrowth of weeds after repeated flame weeding

    DEFF Research Database (Denmark)

    Rask, Anne Merete; Kristoffersen, Palle; Andreasen, Christian

    2013-01-01

    Efficient non-chemical weed control like flame weeding often requires repeated treatments. In weed control experiments the effect of each treatment may be estimated by removing and weighing the remaining weed biomass after the treatment, but the method influences the weed plants ability to regrow......, and therefore it may influence the long-term effect of repeated treatments. Visual assessment of weed cover or image analysis do not affect the remaining parts of the weed plants after treatment, but the methods may have other disadvantages. In order to evaluate and compare three methods we measured changes...... in vegetation cover of perennial ryegrass after flaming by (1) a simple image analysis programme counting green pixels, (2) visual assessment of images and (3) by taking biomass samples. Plants were flame treated with eight different dosages (0, 20, 30, 35, 45, 60, 90 and 180 kg propane ha-1) and with various...

  10. Activities of five enzymes following soil disturbance and weed control in a Missouri forest

    Science.gov (United States)

    Felix, Jr. Ponder; Frieda Eivazi

    2008-01-01

    Forest disturbances associated with harvesting activities can affect soil properties including enzyme activity and overall soil quality. The activities of five enzymes (acid and alkaline phosphatases, betaglucosidase, aryl-sulfatase, and beta-glucosominidase) were measured after 8 years in soil from clearcut and uncut control plots of a Missouri oak-hickory (...

  11. Acquired natural enemies of the weed biological control agent Oxyops vitiosa (Coleoptera: Curculionidae)

    Science.gov (United States)

    The Australian curculionid Oxyops vitiosa Pascoe was introduced into Florida during 1997 as a biological control agent of the invasive tree Melaleuca quinquenervia (Cav.) S.T. Blake. Populations of the weevil increased rapidly and became widely distributed throughout much of the invasive tree’s adve...

  12. Vineyard weeds control practices impact on surface water transfers: using numerical tracer experiment coupled to a distributed hydrological model to manage agricultural practices spatial arrangements.

    Science.gov (United States)

    Colin, F.; Moussa, R.

    2009-04-01

    In rural basins, agricultural landscape management highly influences water and pollutants transfers. Landuse, agricultural practices and their spatial arrangements are at issue. Hydrological model are widely used to explore impacts of anthropogenic influences on experimental catchments. But planning all spatial arrangements leads to a possible cases count which cannot be considered. On the basis of the recent « numerical experiment » approach, we propose a « numerical tracer function » which had to be coupled to a distributed rainfall-runoff model. This function simulate the transfer of a virtual tracer successively spread on each distributed unit inside the catchment. It allows to rank hydrological spatial units according to their hydrological contribution to the surface flows, particularly at the catchment outlet. It was used with the distributed model MHYDAS in an agricultural context. The case study concerns the experimental Roujan vine-growing catchment (1km², south of France) studied since 1992. In this Mediterranean context, we focus on the soil hydraulic conductivity distributed parameter because it highly depends on weed control practices (chemical weeding induces a lot more runoff than mechanical weeding). We checked model sensitivity analysis to soil hydraulic conductivity spatial arrangement on runoff coefficient, peak discharge and catchment lag-time. Results show (i) the use of the tracer function is more efficient than a random approach to improve sensitivity to spatial arrangements from point of view of simulated discharge range, (ii) the first factor explaining hydrological simulations variability was practices area ratio, (iii) variability induced by practices spatial arrangements was significant on runoff coefficient and peak discharge for balanced practices area ratio and on lag-time for low area ratio of chemical weeding practices. From the actual situation on the experimental Roujan catchment (40% of tilled and 60% of non tilled vineyard

  13. Controle de plantas daninhas na cultura do arroz de sequeiro (Oryza sativa L. Weed control in upland rice (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    R. Victoria Filho

    1981-06-01

    Full Text Available Com o objetivo de verificar o controle de plantas daninhas com herbicidas na cultura do arroz de sequeiro, foi conduzido o presente experimento em um latossolo roxo, série Jaboticabal com 4,82% de m.o, utilizando-se a variedade Pratão Precoce. Foram util izados os seguintes tratamentos com as respectivas doses em kg do i.a/ha: pendimethalin a 0,75, 1,00 e 1,50; AC-92390 a 1,00, 2,00 e 3,00; butachlor a 2,05; benthiocarb a 4,50; oxadiazon a 1,0 todos em pré emergência; e propanil a 4,32; propanil + 2,4-D amina a 2,88 + 0,36 e propanil + parathion metílico a 1,98 + 0,24, em pósemergência aos 29 dias após o plantio. As plantas daninhas que ocorreram em maior densidade foram: carrapicho-de-carneiro (Acanthospermum hispidum D.C. , trapoe raba (Commelina sp., falsa-dormideira (Cassia patellaria D.C., anileira (Indigofera hirsuta L., capimcarrapicho (Cenchrus echinatus L., beldroega (Portulacca oleracea L. e guanxuma (Sida sp.. O carrapicho-de-carneiro só foi controlado pelos tratamentos em pós -emergência; a falsa-dormideira pelo butachlor e pelos tratamentos em pós-emergência. No controle geral os melhores indices foram obtidos com os tratamentos em pós-emergência. Os tratamentos em pré-emergência foram capinados aos 36 dias após o pl antio devido ao baixo controle do carrapicho-de-carneiro, e os de pós-emergência aos 54 di as devid o ao baixo controle da trapoeraba. Quanto à fitotoxicidade à cultura o tratamento propanil + parathion metflico atingiu fitotoxicidade quase forte (nota 5,8 pela escala E.W.R.C., todavia não houve diferença significativa entre os diferentes tratamentos com herbicida na produção de grãos.A field trial was performed, on a oxisol (Latos - solic B containing 4.82% organic matter, with the objetive to verify the weed control with pre and postemergence herbicides in upland rice cv "Pratão Precoce". The following treatments were used (kg a.i/ha : pendimethal in at 0,75, 1,00 and 1,50; AC-92390 at 1

  14. Weeds optimally grow in peat swamp after burning

    Directory of Open Access Journals (Sweden)

    P.D. Susanti

    2014-07-01

    Full Text Available After clearing land by burning the peat, then the weeds and undergrowth will flourish. Even sometimes, the weeds are eventually burned again. Weed is known as a destroyer plant that has to be controlled. Through proper treatment, the existing weeds in peatlands can be potentiallly exploited. The purpose of this study was to determine the calorific value of briquettes as one of peatland weeds utilization. The results showed that the calorific value ranged from 2,492 cal/g to 5,230 cal/g. The lowest calorific value was on ‘teki kecil’ grass (Scirpus grossus Lf, while the highest calorific value was observed for ‘bantalaki grass’ (Hymenachne amplexicaulis Nees. The high calorific value of the peat weeds are potential for biomass briquettes raw materials. The utilization and use of peat weed briquettes as a raw materials expected can reduce land degradation due to peat swamp burning

  15. Weeding method and pre-sowing tillage effects on weed growth and pearl millet yield in a sandy soil of the West African Sahelian zone.

    NARCIS (Netherlands)

    Klaij, M.C.; Hoogmoed, W.B.

    1996-01-01

    Weed control for the West African Sahel rainfed crops is done mainly manually, resulting in high labor requirements. Because of the seasonality of rainfed farming, weed control is often late and incomplete, resulting in considerable losses in crop yield. We examined the case of weed control in conti

  16. Weeding out bad waves: towards selective cannabinoid circuit control in epilepsy.

    Science.gov (United States)

    Soltesz, Ivan; Alger, Bradley E; Kano, Masanobu; Lee, Sang-Hun; Lovinger, David M; Ohno-Shosaku, Takako; Watanabe, Masahiko

    2015-05-01

    Endocannabinoids are lipid-derived messengers, and both their synthesis and breakdown are under tight spatiotemporal regulation. As retrograde signalling molecules, endocannabinoids are synthesized postsynaptically but activate presynaptic cannabinoid receptor 1 (CB1) receptors to inhibit neurotransmitter release. In turn, CB1-expressing inhibitory and excitatory synapses act as strategically placed control points for activity-dependent regulation of dynamically changing normal and pathological oscillatory network activity. Here, we highlight emerging principles of cannabinoid circuit control and plasticity, and discuss their relevance for epilepsy and related comorbidities. New insights into cannabinoid signalling may facilitate the translation of the recent interest in cannabis-related substances as antiseizure medications to evidence-based treatment strategies.

  17. Phenrica littoralis a potential candidate for the biological control of alligator weed, Alternanthera philoxeroides: redscription of the adult, first description of immature stages and biological notes

    Science.gov (United States)

    Flea beetles of aliligator weed, Alternanthera philoxeroides (Martius) Grisebach (Amaranthaceae), were collected in Argentina, Uruguay, Paraguay and Brazil. Species in the genera Disonycha Chevrolat, Agasicles Jacoby Systena Chevrolat and Phenrica Bechyne were frequently found on this weed. Phenric...

  18. Variabilidade da infestação em duas variedades de trigo mole (Triticum Aestivum L.. I: em função da data de sementeira e do controlo das plantas infestantes em pós-emergência Variability of weed infestation in two wheat varieties (Triticum Aestivum L.. I: as influenced by sowing date and post-emergence weed control

    Directory of Open Access Journals (Sweden)

    José Manuel Godinho Calado

    2008-01-01

    Full Text Available Neste trabalho, procurou-se verificar a influência da data de sementeira e do controlo das infestantes na infestação e na produção de duas variedades de trigo mole (Sever e Centauro, a partir de um ensaio instalado durante quatro anos (1996/97 a 1999/00 na Herdade da Revelheira, concelho de Reguengos de Monsaraz. De acordo com a análise dos resultados, constatou-se que a sementeira do trigo efectuada no início de Novembro permitiu a ocorrência de maior infestação na cultura relativamente à realizada no fim de Novembro e, em consequência, as perdas de produção do trigo sem aplicação de um herbicida em pós-emergência foram maiores. Portanto, a aplicação de um herbicida em pós-sementeira, nas condições mediterrânicas do Sul de Porugal, é mais relevante para diminuir a infestação e as perdas produtivas do trigo quando a sementeira é precoce (realizada no início de Novembro.The density of weed infestation of a crop is influenced by its sowing date due the variability of the control of the spontaneous flora in pre-emergence, depending on the level of weed emergence before sowing. In this study the effect of different sowing dates of two wheat varieties (Sever and Centauro and post-emergence weed control was analyzed in terms of weed infestation and crop performance. The trials were carried out over four years (1996/97 until 1999/00 on the farm “Revelheira” belonging to the Regional Directorate of Agriculture in the Reguengos de Monsaraz municipality. When sowing was carried out in the beginning of November and without post-emergence weed control weed infestation during the crop cycle was much higher when compared to the sowing date at the end of November. Consequently, yield reduction was much more pronounced at the early sowing date. Thus, for early sowing dates, post-emergence weed control under Mediterranean conditions seems to be essential to avoid severe weed infestation and unacceptable crop yield reductions.

  19. Weed suppression and weed tolerance of wheat cultivars - relevant traits for Integrated Pest Management

    Directory of Open Access Journals (Sweden)

    Verschwele, Arnd

    2014-02-01

    Full Text Available An assortment of 10 winter wheat cultivars was tested for specific effects on weed suppression. Furthermore cultivar specific effects of weed infestation and weed control measures on the crop yield were investigated. Two trial series conducted from 2005 to 2010 demonstrated a wide cultivar specific range of shading capacity and weed suppression. Light penetration and the dry matter of the model weed Sinapis alba were highly correlated (r = 0.87 in trial series A (2005-2007. Consequently, the weed dry matter in the less competitive cultivar Dekan was 5 times higher compared to the weak competitor Cubus. Mechanical weed control by harrowing reduced ears density of all cultivars tested in trial series A. These reductions were significantly higher in the cultivars Bussard and Pegassos compared to the other cultivars. Since the weed infestation was low and negative crop effects by harrowing could be compensated by a higher number of kernels/ear, the yield effects were the same for all cultivars. Contrary to the hypothesis, a cultivar specific yield response by harrowing could not be assessed. Higher competition effects by sowing the model weed Sinapis alba could be realised in trial series B (2008-20120. Consequently, the control measures (a harrowing (b 50% herbicide (c 100% herbicide resulted in significantly higher crop yields ranging from 1.23 t*ha-1 (harrowing to 2.08 t*ha-1 (100% herbicide. The yield reduction caused by the model weed was not the same for all cultivars and was lower for the cultivars Cubus and Limes (6% and 7% compared to Boomer (15%. Thus, weed tolerance could be identified as a cultivar specific trait. There were significant interactions between cultivar and weed control measures: The yield increase (relative to model weed was 5% for Bussard, which was much lower compared to the treatment effects on the cultivar Impression (11%. The hypothesis that yield effects by mechanical and chemical weed control may be affected by the

  20. 5种除草剂防除旱直播稻田杂草比较试验%Comparative Test of Weed Control Efficacy of Five Herbicides in Dry Direct-seeding Rice Field

    Institute of Scientific and Technical Information of China (English)

    赵海英; 卢兆成; 乔利; 杨黎明

    2012-01-01

    This field experiment selected five herbicides to apply in the dry direct-seeding rice field for comparative test of its weed controlling efficiency. The results showed that weeds controlling effeciency of butachlor + oxadiazon 42% EC 1 500 mL/hm2 was 82% to control Yerbadetajo Herb, 100% to control poaceae weeds,most broadleaf weeds and sedges; controlling efficiency of phendimethalin 33% EC 2 250 mL/hm2 was 64.7% to control Yerbadetajo Herb,86% - 100% to control poaceae weeds, some broadleaf weeds and sedges ; controlling efficiency of butachlor + bensulfuron methyl 30% WP 2 250 g/hm2 and pretilachlor + bensulfuron 35% WP 900g/hm2 was higher to broadleaf weeds and sedges ,but low to poaceae weeds;controlling efficiency of pretilachlor 30% wp 1 800g/hm2 was lower than 63% to most of the weeds varieties in the rice direct-seeding field.%42%噁草·丁草胺EC1500 mL/hm2对鳢肠的防效为82%,对禾本科杂草、大多数阔叶杂草及莎草均有良好的防除效果,防效均达100%;33%二甲戊灵EC 2250 mL/hm2对旱莲草的防效为64.7%,对禾本科杂草和部分阔叶杂草及莎草的防效均在86%~100%之间;30%苄·丁Wp2250 g/hm2和35%苄嘧·丙草胺WP 900 g/hm2对阔叶杂草和莎草科杂草的防效较好,但对禾本科杂草的防效较差;30%丙草胺EC1 800 mL/hm2对稻田多种杂草的防效均低于63%.

  1. Control of ALS resistant volunteer oil seed rape and other dicotyledonous weeds with GF-145, a new cereal herbicide product containing isoxaben and florasulam

    Directory of Open Access Journals (Sweden)

    Becker, Jörg

    2014-02-01

    Full Text Available GF-145 contains the active ingredients isoxaben (610 g ai/kg and florasulam (40 g ai/kg and is formulated as a Wettable Granule (WG. The active ingredients are found in commercial products such as Primus™2 (florasulam, Starane XL™ (fluroxypyr + florasulam, Ariane C™ (fluroxypyr + florasulam + clopyralid or Flexidor™ (isoxaben. While florasulam has been widely used in cereal crops in recent years, isoxaben offers a new mode of action (MOA for use in German cereal herbicides even when considering that Flexidor™ has had regulatory approval in 1988 to 1991. The MOA of isoxaben is inhibition of cellulose synthesis (HRAC class L, while florasulam inhibits Acetolactate Synthase (ALS and is a representative of the HRAC class B. It is known that florasulam works through uptake by green leaves. Isoxaben is a herbicide with soil activity and with a very low activity when foliar applied, except on some species in the cruciferae family. GF-145 is intended to be applied in the autumn in cereals (wheat, barley, rye, triticale for the control of ALS resistant volunteer oil seed rape and annual dicotyledonous weeds including Matricaria spp., Stellaria media, Papaver rhoeas, Capsella bursa-pastoris, Myosotis arvensis, Lamium spp., Galium aparine, Veronica spp. and others when applied at early post-emergence from BBCH 10 to 13 of the crop. The use rate in winter cereals is 95 g product/ha (58 g ai/ha isoxaben plus 3.75 g ai/ha florasulam. Field trials conducted in previous years confirmed excellent selectivity in all cereal crops and efficacy trials initiated in autumn 2012 show that GF-145 provides excellent and superior control to ALS resistant oil seed rape that was better than straight florasulam and other ALS active ingredients. GF-145 adds a new MOA to the cereal herbicide portfolio and controls volunteer oil seed rape, cruciferous weeds and broad-leaved weeds and is more robust than florasulam based products that do not contain isoxaben.

  2. Eficácia de herbicidas no controle de plantas daninhas na cultura da cebola em semeadura direta Efficacy of herbicides on weed control in onion direct sowing

    Directory of Open Access Journals (Sweden)

    Lino R. Ferreira

    1999-04-01

    Full Text Available As plantas de cebola provenientes da semeadura direta no campo são mais danificadas pelo cultivo mecânico e são mais sensíveis aos herbicidas, principalmente os latifolicidas, do que quando transplantadas. Com o objetivo de avaliar a eficácia dos herbicidas oxyfluorfen, ioxynil-octanoato e fluazifop-p-butil, aplicados em pós-emergência, isoladamente ou em mistura no tanque, com ou sem aplicação de paraquat, antes da emergência das plantas de cebola, conduziu-se este trabalho no município de Monte Alto, SP. Nenhum dos herbicidas aplicados isoladamente foi eficiente no controle de todas as espécies daninhas presentes na área experimental. As misturas no tanque de fluazifop-p-butil com oxyfluorfen ou ioxynil-octanoato, independente da aplicação ou não de paraquat aos cinco dias após a semeadura, controlaram eficientemente Portulaca oleracea, Amaranthus lividus, Echinochloa crusgalli, Eragrostis pilosa, Digitaria horizontalis, Eleusine indica e Brachiaria plantaginea, com produção de bulbos semelhante à da testemunha capinada.Onion plants, from direct sowing to the field, are more damaged by mechanical cultivation and more sensitive to herbicides, especially to broadleaf herbicides, than transplanted onions. With the purpose of evaluating the efficacy of the herbicides oxyfluorfen, ioxynyl-octanoato and fluazifop-p-butyl, applied in post-emergence, alone or tank mix, with or without paraquat application, before onion plants emergence, this investigation was carried out at Monte Alto County, São Paulo State, Brazil. None of the herbicides sprayed alone were efficient in the control of all the weeds present in the experimental area. The tank mix of fluazifop-p-butyl plus oxyfluorfen or ioxynyl-octanoato, regardless of paraquat application, at five days after sowing, controlled efficiently Portulaca oleracea, Amaranthus lividus, Echinoclhoa crusgalli, Eragrostis pilosa, Digitaria horizontalis, Eleusine indica and Brachiaria

  3. Controle de plantas daninhas na cultura do milho (Zea mays L. por meio de herbicidas Weed control in maize (Zea mays L. with herbicides

    Directory of Open Access Journals (Sweden)

    C. A. L. dos Santos

    1979-12-01

    Full Text Available Com o objetivo de se verificar a ação do butylate, aplicado isoladamente e em mistura com atrazine, no controle de plantas daninhas da cultura do milho, foi instalado um experimento de campo em solo fino areno-argiloso. Foram utilizados os seguintes tratamentos: butylate a 2,80; 3,60 e 4,32 kg/ha (p.p.i.; butylate + atrazine a 3,24 + 0,80; 3,24 + 1,20 e 3,60 + 0,96 kg/ha (p.p.i.; atrazine a 3,00 kg/ha e atrazine + metolachlor a 1,40 + 2,10 kg/ha, ambos aplicados em pré-emergência e empregados como herbicidas padrão para a cultura. As plantas daninhas encontradas foram: tiririca - Cyperus rotundus L., carurú comum - .:maranthus viridis L., capim de colchão - Digitaria sanguinalis (L. Scop. e capim pé-de-galinha Eleusine indica (L. Gaertn. Butylate nas três doses apresentou-se bem contra C. rotundus e E. indica; nas doses de 3,60 e 4,32 kg foram obtidos bons resultados sobre D. sanguinalis. Butylate + atrazine controlou, nas três doses, todas as espécies incidentes, o mesmo ocorrendo com a mistura atrazine + metolachlor. Atrazine foi mais eficiente para A. viridis e E. indica. Nas condições em que foi conduzido o experimento nenhum dos herbicidas foi prejudicial para a cultura.Butylate at 2.80; 3.60 and 4.32 kg/ha and butylate + atrazine at. 3.24 + 0.80; 3.24 + 1.20 and 3.60 + 0.96 kg, were applied in preplant incorporated; atrazine at 3.00 kg and atrazine + metolachlor at 1.40 + 2.10 kg were applied in preemergence on corn. The weeds were represented by Cyperus rotundus L., Amaranthus viridis L., Digitaria sanguinalis (L. Scop. and Eleusine indica (L. Gaertn. Butylate + atrazine, in all rates, atrazine + metolachlor and atrazine gave good control of the weeds in general. Butylate, in the three rates, controlled C. rotundus and E. indica; at 3.60 and 4.32 kg/ha controlled well D. sanguinalis. The herbicides did not cause injuries to the crop.

  4. RNAseq reveals weed-induced PIF3-like as a candidate target to manipulate weed stress response in soybean.

    Science.gov (United States)

    Horvath, David P; Hansen, Stephanie A; Moriles-Miller, Janet P; Pierik, Ronald; Yan, Changhui; Clay, David E; Scheffler, Brian; Clay, Sharon A

    2015-07-01

    Weeds reduce yield in soybeans (Glycine max) through incompletely defined mechanisms. The effects of weeds on the soybean transcriptome were evaluated in field conditions during four separate growing seasons. RNASeq data were collected from six biological samples of soybeans growing with or without weeds. Weed species and the methods to maintain weed-free controls varied between years to mitigate treatment effects, and to allow detection of general soybean weed responses. Soybean plants were not visibly nutrient- or water-stressed. We identified 55 consistently downregulated genes in weedy plots. Many of the downregulated genes were heat shock genes. Fourteen genes were consistently upregulated. Several transcription factors including a PHYTOCHROME INTERACTING FACTOR 3-like gene (PIF3) were included among the upregulated genes. Gene set enrichment analysis indicated roles for increased oxidative stress and jasmonic acid signaling responses during weed stress. The relationship of this weed-induced PIF3 gene to genes involved in shade avoidance responses in Arabidopsis provide evidence that this gene may be important in the response of soybean to weeds. These results suggest that the weed-induced PIF3 gene will be a target for manipulating weed tolerance in soybean.

  5. Weed Characteristics and Control Strategies in Wheat Fields in Yangzhou City%扬州市麦田草相特点及杂草防除对策

    Institute of Scientific and Technical Information of China (English)

    杨进; 刘学儒; 丁涛; 秦玉金; 焦骏森

    2014-01-01

    为了摸清扬州地区麦田杂草种类、分布状况,通过倒“W”形九点取样法调查,结果表明麦田杂草有26科81种,其中里下河地区优势种为日本看麦娘、牛繁缕、菵草等;沿江地区优势种为菵草、日本看麦娘、牛繁缕等;丘陵山区优势种为日本看麦娘、猪秧秧、野老鹳等;同时发现当前存在着杂草抗药性增强、防治技术不到位等方面问题,提出了强抓土壤封闭处理、合理选用除草剂及开展技术宣传培训等对策。%Weed species and their distribution in wheat fields in Yangzhou area were determined by sampling nine plots according to a“W” pattern.Weeds belonged to 81 species of 26 families.The dominant species in Lixiahe region and the area along the Yangtze River were Alopecurus japonicus Steud.,Malachium aquaticum ( L.) Fries., and Beckmannia syzigachne ( Steud.) Fernald, whereas A.japonicus Steud.,Galium aparine L.and Geranium carolinianum L.were dom-inant in hilly areas.Currently,problems with herbicide resistant weeds are becoming more serious and outdated control technologies must be improved.Therefore,a series of control strategies are proposed including improving the use of resid-ual soil applied herbicides,judicious selection of herbicides and carrying out technical outreach and training.

  6. IAA Producing Enterobacter sp. I-3 as a Potent Bio-herbicide Candidate for Weed Control: A Special Reference with Lettuce Growth Inhibition.

    Science.gov (United States)

    Park, Jae-Man; Radhakrishnan, Ramalingam; Kang, Sang-Mo; Lee, In-Jung

    2015-06-01

    Development of bio-herbicides is an emerging method to weed management in agricultural field. Very few studies were conducted on identification of microbial bio-herbicides to weed control. The present study was aimed to isolate and identify the effective bio-herbicide potential bacterium from soil and assess their role on plant growth inhibition. Three-hundred and one rhizobacteria were isolated from agriculture field soil samples collected from various parts of Republic of Korea. Two bacterial strains, I-4-5 and I-3 were significantly reduced the seedling growth of radish when compared to their controls. The highest rate of seedling growth inhibition was observed in I-3 bacterial isolate treatment in lettuce and radish. The mechanism of an effective bio-herbicide I-3 to plant growth inhibition was determined by analyzing IAA in their culture medium. IAA biosynthesis pathway of Enterobacter sp. I-3 was identified as tryptophan-dependent pathway and its production was increased due to addition of tryptophan in culture medium as quantified by using GC-MS SIM. In an in vitro study revealed that I-3 bacterial culture exudate combined with tryptophan significantly decreased leaf length, leaf width, root length and increased the number of lateral roots of lettuce. Indeed, the genomic DNA of I-3 bacterium was isolated and 16S rDNA was sequenced to find out the name of the bacterium. Based on phylogenetic analysis, I-3 isolate was identified and named into Enterobacter sp. I-3. The results of this study suggest that the utilization of Enterobacter sp. I-3 to crop field can be act as a potential bio-herbicide against weed growth.

  7. Periods of weed interference in cowpea

    Directory of Open Access Journals (Sweden)

    Maria José Pinheiro Corrêa

    2015-12-01

    Full Text Available This work aimed to determine the periods weed interference in cowpea. The experimental design was randomized blocks, and the treatments consisted of periods of control or coexistence with the culture. The periods of control or weed coexistence after culture emergence were: 0-10, 0-20, 0-30, 0-40, 0-50, 0-60 and 0 – 80 days after crop emergence. The main weed density were: AlternantheratenellaColla,CyperusrotundusL., Digitariaciliaris(Retz. Koeler, Eleusineindica(L.Gaertn,MollugoverticillataL.Considering 5% of tolerance in cowpea yield reduction, the period prior interference was 8 days after emergence (DAE, total period of interference prevention was 53 DAE and critical period of interference prevention between 8 and 53 DAE. Weed interference reduced the grainyield up to 46%.

  8. Potential Use of Essential oils from Four Tunisian Species of Lamiaceae: Biological Alternative for Fungal and Weed Control

    Directory of Open Access Journals (Sweden)

    Mohsen Hanana

    2017-05-01

    Full Text Available The chemical composition of the essential oils (EOs of four Lamiaceae (Thymus capitatus Hoff. et Link. , Rosmarinus officinalis L., Origanum vulgare L. and Mentha pulegium L. growing wild in Tunisia was analyzed by gas chromatography (GC and gas chromatography-mass spectrometry (GC-MS. Obtained results showed significant variations among the different species. The major constituents identified for each species were respectively carvacrol (69% and δ-terpinene (17% for T. capitatus, 1,8-cineole (41% and α-pinene (24% for R. officinalis, menthol (39% and 1.8-cineole (17% for M. pulegium , thymol (30%, p-cymene (30% and δ-terpinene (27% for O. vulgare . EO herbicidal effects were evaluated against three invasive weed species in most cultivated crops: Sinapis arvensis L., Phalaris paradoxa L. and Lolium rigidum Gaud. The study of herbicidal activity was carried out on seed germination and seedling vigor and growth. All tested EOs significantly inhibited the germination and growth of weeds in a dose dependent manner and their herbicidal activity could be attributed mainly to their high content in oxygenated monoterpenes. The antifungal ability of EOs was assessed by using disc agar diffusion against ten plant pathogenic fungi affecting crops and stored foods. The EOs displayed strong inhibitory effect on all tested fungi. Our results on EOs chemical composition and biological activities showed properties that could be valorized in managing biocontrol of weeds and plant fungi.

  9. 施用稻糠对稻田除草及水稻分蘖和产量的影响%Effect of Rice Bran on Weed Controlling,Tillering and Yield

    Institute of Scientific and Technical Information of China (English)

    孙淑红; 庄同春; 孙海正; 赵凤民; 王立楠; 薛菁芳

    2011-01-01

    以优质、高产、抗病和耐寒水稻新品种龙粳20为材料,研究了化学药剂、稻糠+化学药剂和单施稻糠对水稻的除草效果、水稻分蘖和产量的影响。结果表明:单施稻糠具有一定的除草效果,但结合前期封闭除草后期再施用稻糠效果更好。并且分蘖增加,增产45%左右。%High quality,high yield and disease resistance,cold rice variety Longjing 20 was used to study the effect of chemical weeding,rice bran and chemical weeding,rice bran single on weed controlling,rice tillering and yield.The results showed that rice bran single had certain effect on weed controlling,but combining with closure weed controlling in early stage,applying rice bran later,the effect was better,which increasing tillering and yield about 45%.

  10. Chemical Weed-control Technique in Machine-transplanted Fields of Single Late Rice%单季晚稻机插田化学除草技术

    Institute of Scientific and Technical Information of China (English)

    赵敏; 李荣; 张国忠; 吴传伟; 洪美萍; 徐福寿; 陈建明

    2011-01-01

    [目的]随着小苗机插稻田面积的扩大,机插田草害发生也日益严重,为有效控制机插田杂草的危害,2008-2009年在浙江省桐庐县单季晚稻机插田进行不同施药时期和施药剂量对主要杂草防效试验.[结果]5%丁草胺GR 750 g a.i./hm+10%苄嘧磺隆WP 30 g a.i./hm和20%乙·苄WP 90 g a.i./hm在插后3 d施药.插后50d对总草鲜质量防效极显著高于插后7 d的防效.53%苄嘧·苯噻酰WP 318、477、636 g&iAun~于插后5 d施药,药后30、50 d,对异型莎草、阔叶草、总杂草的防效有差异;而50%苄·丁·异丙隆WP 450、600 g a.i/hm的防效差异均不显著;药后50 d对总草株防效均达93%以上、鲜质量防效99%以上.且增产8.2%~14.4%.上述处理除20%乙·苄WP 90 g a.i./hm在药后15 d内对机插稻有一定影响外,其余均较安全.[结论]在小苗机插后3-5 d,使用5%丁草胺GR 750 g a.i./hm+10%苄嘧磺隆WP 30 g a.i./hm或53%苄嘧·苯噻酰WP 318~636 g a.i./hm,或50%苄·丁·异丙隆WP 450~600 g a.i./hm拌肥或拌土150 kg/hm能有效控制机插田杂草的为害,且对机插稻安全.%[Aims]With the increase of area of machine-transplanted rice fields, occurrence of weeds was also increasingly serious.Field efficacy of different spraying time and spraying doses to major weeds was evaluated in machinetransplanted fields in Tonglu county of Zhejiang province during the years of 2008 to 2009 in order to effectively control the damage of weeds.[Results]Field efficacy of the mixture of butachlor 5% GR 750 g ai./ha and bensulfuron methyl 10% WP 30 g a.i./ha, and acetochlor· bensulfuron-methyl 20% WP 90 g a.i./ha sprayed on the 3rd day after machine-transplanting on fresh weight of total weeds were significantly higher than those on the 7th day after machinetransplanted for 50 days after machine-transplanting.On the 5th day spraying after machine-transplanted, control efficacy of bensulfuron methyl· mefenacet 53% WP at different doses(318, 477

  11. Effect of cowpea intercropping on weed control and corn yieid Efeito da consorciação do feijão-caupi no controle de plantas daninhas e no rendimento do milho

    Directory of Open Access Journals (Sweden)

    P.S.L. Silva

    2009-01-01

    Full Text Available Herbicides have simplified weed control, but the use of herbicides, besides being costly, resulted in the selection of herbicide-resistant weed biotypes and has become an environmental contamination factor. Herbicide use reduction is one of the goals of modern agriculture, with several alternatives being investigated, including intercropping. The objective of this study was to evaluate the effects of cowpea and corn cultivar intercropping on weed control and corn green-ear (immature ears with 80% humidity grains and grain yield. A completely randomized block design with split-plots and four replications was used. AG 1051, AG 2060 and PL 6880 corn cultivars (assigned to plots were submitted to the four treatments: no weeding, two hoe-weeding (22 and 41 days after planting, and intercropping with cowpea (BR 14 and IPA 206 cultivars, with indeterminate growth. The cowpea was planted (with corn planting between the corn rows, in pits 1.0 m apart, with two plants per pit. The corn cultivars did not differ from each other as to weed density (WD, fresh above-ground weed biomass (WB, green-ear yield and grain yields. Higher WD and WB mean values were found in no weeding subplots; lower mean values in two hoe-weeding subplots; and intermediate mean values in intercropped subplots, indicating that cowpea plants had, to a certain extent, control over weeds. The no-weeded plots and the intercropped plots had lower green-ear and grain yields. Although the cowpea cultivars had a certain control over weeds (mean reductions of 22.5 and 18.3%, in terms of green matter density and weight of the above-ground part of weeds, respectively, they also competed against the corn plants, leading to yield reduction (mean reductions of 17.0 and 32% in green ear and grain yield, respectively. The cowpea cultivars did not produce grain, certainly due to the strong competition exerted by the corn and weeds on cowpea plants.Os herbicidas têm simplificado o controle de plantas

  12. Yield loss prediction models based on early estimation of weed pressure

    DEFF Research Database (Denmark)

    Asif, Ali; Streibig, Jens Carl; Andreasen, Christian

    2013-01-01

    Weed control thresholds have been used to reduce costs and avoid unacceptable yield loss. Estimation of weed infestation has often been based on counts of weed plants per unit area or measurement of their relative leaf area index. Various linear, hyperbolic, and sigmoidal regression models have...... been proposed to predict yield loss, relative to yield in weed free environment from early measurements of weed infestation. The models are integrated in some weed management advisory systems. Generally, the recommendations from the advisory systems are applied to the whole field, but weed control...... time of weeds relative to crop. The aim of the review is to analyze various approaches to estimate infestation of weeds and the literature about yield loss prediction for multispecies. We discuss limitations of regression models and possible modifications to include the influential factors related...

  13. Weeding Library Collections.

    Science.gov (United States)

    Slote, Stanley J.

    This work, based on two recent research projects in the weeding of library collections and the identification of core collections, provides a comprehensive summary of the literature and research on these topics. It also presents practical guidance in weeding for the professional librarian or for the library school student. The book is divided into…

  14. RoboWeedSupport

    DEFF Research Database (Denmark)

    Dyrmann, Mads; Nyholm Jørgensen, Rasmus

    2015-01-01

    Information about the weed population in fields is important for determining the optimal herbicides for the fields. A system based on images is presented that can provide support in determining the species and density of the weeds. Firstly, plants are segmented from the soil. Plants that after th...

  15. A strategy to provide long-term control of weedy rice while mitigating herbicide resistance transgene flow, and its potential use for other crops with related weeds.

    Science.gov (United States)

    Gressel, Jonathan; Valverde, Bernal E

    2009-07-01

    Transgenic herbicide-resistant rice is needed to control weeds that have evolved herbicide resistance, as well as for the weedy (feral, red) rice problem, which has been exacerbated by shifting to direct seeding throughout the world-firstly in Europe and the Americas, and now in Asia, as well as in parts of Africa. Transplanting had been the major method of weedy rice control. Experience with imidazolinone-resistant rice shows that gene flow to weedy rice is rapid, negating the utility of the technology. Transgenic technologies are available that can contain herbicide resistance within the crop (cleistogamy, male sterility, targeting to chloroplast genome, etc.), but such technologies are leaky. Mitigation technologies tandemly couple (genetically link) the gene of choice (herbicide resistance) with mitigation genes that are neutral or good for the crop, but render hybrids with weedy rice and their offspring unfit to compete. Mitigation genes confer traits such as non-shattering, dwarfism, no secondary dormancy and herbicide sensitivity. It is proposed to use glyphosate and glufosinate resistances separately as genes of choice, and glufosinate, glyphosate and bentazone susceptibilities as mitigating genes, with a six-season rotation where each stage kills transgenic crop volunteers and transgenic crop x weed hybrids from the previous season.

  16. Hot foam for weed control-Do alkyl polyglucoside surfactants used as foaming agents affect the mobility of organic contaminants in soil?

    Science.gov (United States)

    Cederlund, H; Börjesson, E

    2016-08-15

    Use of alkyl polyglucosides (APGs) as a foaming agent during hot water weed control may influence the environmental fate of organic contaminants in soil. We studied the effects of the APG-based foaming agent NCC Spuma (C8-C10) on leaching of diuron, glyphosate, and polycyclic aromatic hydrocarbons (PAHs) in sand columns. We also examined how APG concentration affected the apparent water solubility and adsorption of the herbicides and of the PAHs acenaphthene, acenaphthylene and fluorene. Application of APGs at the recommended concentration of 0.3% did not significantly affect leaching of any of the compounds studied. However, at a concentration of 1.5%, leaching of both diuron and glyphosate was significantly increased. The increased leaching corresponded to an increase in apparent water solubility of diuron and a decrease in glyphosate adsorption to the sand. However, APG addition did not significantly affect the mobility of PAHs even though their apparent water solubility was increased. These results suggest that application of APG-based foam during hot water weed control does not significantly affect the mobility of organic contaminants in soil if used according to recommendations. Moreover, they suggest that APGs could be useful for soil bioremediation purposes if higher concentrations are used.

  17. Propelled abrasive grit applications for weed management in transitional corn grain production systems

    Science.gov (United States)

    Weed control is challenging to farmers who are transitioning from production systems that use synthetic herbicides to organic systems. A two-year field study examined weed control efficacy and corn grain yield of air-propelled corncob grit abrasion for in-row weed control. Grits were applied based o...

  18. Weed infestation of onion in soil reduced cultivation system

    Directory of Open Access Journals (Sweden)

    Marzena Błażej-Woźniak

    2013-12-01

    Full Text Available Field experiment was conducted in the years 1998-2000 in GD Felin. The influence of no-tillage cultivation and conventional tillage with spring ploughing on weed infestation of onion was compared. In experiment four cover crop mulches (Sinapis alba L., Vicia sativa L., Phacelia tanacetifolia B., Avena sativa L. were applied. From annual weeds in weed infestation of onion in great number Matricaria chamomilla L., and Senecio vulgaris L. stepped out. and from perennial - Agropyron repens (L.P.B. Reduced soil cultivation system (no-tillage caused the significant growth of primary weed infestation of onion in comparison with conventional tillage. In all years of investigations the executed pre-sowing ploughing limited significantly the annual weeds' number in primary weed infestation. The applied mulches from cover plants limited in considerable degree the number of primary weed infestation. In all years of investigations the most weeds stepped out on control object. Among investigated cover crop mulches Vicia sativa L. and Avena sativa L. had a profitable effect on decrease of onion`s primary weed infestation. Soil cultivation system and cover crop mulches had no signi ficant residual influence on the secondary weed infestation of onion.

  19. Effect of tillage system on yield and weed populations of soybean ( Glycin Max L.).

    Science.gov (United States)

    Hosseini, Seyed Z; Firouzi, Saeed; Aminpanah, Hashem; Sadeghnejhad, Hamid R

    2016-03-01

    Field experiment was conducted at Agricultural and Natural Resources Research Center of Golestan Province, Iran, to determine the effects of tillage system and weed management regime on yield and weed populations in soybean ( Glycin max L.). The experimental design was a split plot where the whole plot portion was a randomized complete block with three replicates. Main plots were tillage system: 1- No-till row crop seeding, 2- No-till seed drilling, 3- Tillage with disc harrow and drill planting, 4- Tillage with chisel packer and drill planting. The subplots were weed management regimes: 1-Weed control with herbicide application, 2- Hand weeding, 3- Herbicide application plus hand weeding, and 4- Non-weeding. Results indicated that the main effects of tillage system and weed management regime were significant for seed yield, pod number per plant, seed number per pod, weed density and biomass, while their interaction were significant only for weed density, weed biomass, and seed number per pod. The highest grain yields (3838 kg ha-1) were recorded for No-till row crop seeding. The highest seed yield (3877 kg ha-1) also was recorded for weed control with herbicide and hand weeding treatment, followed by hand weeding (3379 kg ha-1).

  20. Effect of tillage system on yield and weed populations of soybean ( Glycin Max L.

    Directory of Open Access Journals (Sweden)

    Seyed Z. Hosseini

    2016-03-01

    Full Text Available Field experiment was conducted at Agricultural and Natural Resources Research Center of Golestan Province, Iran, to determine the effects of tillage system and weed management regime on yield and weed populations in soybean ( Glycin max L.. The experimental design was a split plot where the whole plot portion was a randomized complete block with three replicates. Main plots were tillage system: 1- No-till row crop seeding, 2- No-till seed drilling, 3- Tillage with disc harrow and drill planting, 4- Tillage with chisel packer and drill planting. The subplots were weed management regimes: 1-Weed control with herbicide application, 2- Hand weeding, 3- Herbicide application plus hand weeding, and 4- Non-weeding. Results indicated that the main effects of tillage system and weed management regime were significant for seed yield, pod number per plant, seed number per pod, weed density and biomass, while their interaction were significant only for weed density, weed biomass, and seed number per pod. The highest grain yields (3838 kg ha-1 were recorded for No-till row crop seeding. The highest seed yield (3877 kg ha-1 also was recorded for weed control with herbicide and hand weeding treatment, followed by hand weeding (3379 kg ha-1.

  1. Plant spacing and weed control affect sunflower stalk insects and the girdling behavior of Dectes texanus (Coleoptera: Cerambycidae).

    Science.gov (United States)

    Michaud, J P; Stahlman, P W; Jyoti, J L; Grant, A K

    2009-06-01

    We conducted a 2-yr study to determine the effects of crop density and weeds on levels of damage caused by stalk-boring insects in rain-fed sunflowers in west-central Kansas. Weed-free sunflower had higher seed weight and oil content in 2007, but not in 2006, but weeds did not affect infestation by stalk-boring insects in either year. High-density sunflower had lower estimated seed yield per unit area than low-density sunflower in both years, but percentage oil was slightly greater in the high-density treatment in 2006. Sunflowers were more heavily infested by larvae of Ataxia hubbardi Fisher, Cylindrocopturus adspersus (Leconte), and Pelochrista womanana (Kearfott) in 2006 than in 2007, ostensibly as a result of being planted earlier. Larvae of Dectes texanus LeConte appeared unaffected by planting date and were present in > 70% of plants in both years. Conditions during the period of crop maturity were much drier in 2006 than in 2007 and were associated with higher seed oil content and earlier and faster progression of stalk girdling by D. texanus larvae in both low- and high-density plots. There was also a strong effect of plant density on girdling behavior that seemed to be mediated by effects on soil moisture. Stalk girdling began earlier in high-density plots and a larger proportion of plants were girdled compared with low-density plots on all sampling dates in both years. Certain cultural tactics, in particular reduced plant spacing, have potential to delay the onset of girdling behavior by D. texanus larvae and thus mitigate losses that otherwise result from the lodging of girdled plants.

  2. [Species, Damage and Community Structure of Weeds in Scrophularia ningpoensis Fields in Nanchuan, Chongqing].

    Science.gov (United States)

    Han, Feng; Xiao, Jie-yi; Cao, Hou-qiang; Luo, Chuan; Yang, Tian-jian; Lin, Mao-xiang

    2015-10-01

    To investigate the damage and community structure of weeds in Scrophularia ningpoensis fields in Nanchuan, Chongqing. From 2013 to 2014, an investigation was carried out by inverted W-9 point sampling method to study the weed species. 96 weed species belonged to 75 genera of 30 families were observed, including 18 species of Asteraceae weeds (accounted for 18.75%), 10 species of Poaceae weeds (accounted for 10.42%). Moreover, there were 57 species of annual weeds (accounted for 59.38%) and 39 species of perennial weeds (accounted for 40.63%). The overall abundance of Erigeron annuus, Digitaria adscendens, Torilis scabra, Polygonum nepalense, Ranunculus japonicas, Stellaria media and Commelina communis were relatively higher than that of the others. The difference of weed species and community structure might result from the physical and chemical characteristics of soil, moisture content, cropping system, tillage type, environmental and climatic conditions, crop distribution and weed control.

  3. Controle de plantas daninhas em feijão num sistema de rotação culturas em plantio direto Weed control in beans in a no-tillage crop rotation system

    Directory of Open Access Journals (Sweden)

    Benedito N. Rodrigues

    1995-01-01

    Full Text Available O objetivo deste trabalho foi selecionar culturas de inverno para formação de cobertura morta que reduza a população de plantas daninhas na cultura do feijão (Phaseolus vulgaris. Ocupou-se o terreno durante o ano todo, com a sucessão, em plantio direto, de pousio ou cultura de inverno/feijão/cultura para silagem, estudando-se três modalidades de controle de plantas daninhas na cultura do feijão. A maior renda líquida acumulada após duas safras foi obtida com feijão semeado sobre palha de aveia-preta e controle de plantas daninhas com um gramicida pré-emergente, completando-se com capinas, quando necessário.This study was undertaken to select winter crops for mulching to reduce the weed infestation and to lower weed control costs in bean (Phaseolus vulgaris production. The soil was kept convered all the year under no-tillage with a sequence of a winter crop or fallow/beans/silage crop. Three weed control methods for beans were studied. After two complete crop sequences, the highest total net income was obtained with the beans directly drilled on the black oats (Avena strigosa mulching, spraying a pre-emergence grasskiller plus hoeing when needed.

  4. Activity of mesotrione on resistant weeds in maize.

    Science.gov (United States)

    Sutton, Peter; Richards, Claire; Buren, Larry; Glasgow, Les

    2002-09-01

    Mesotrione is a new callistemone herbicide that inhibits the HPPD enzyme (p-hydroxyphenylpyruvate dioxygenase) and introduces a new naturally selective tool into weed-management programmes for use in maize. Mesotrione provides control of the major broad-leaved weeds, and it can be used in integrated weed-management programmes depending on the grower's preferred weed-control strategy. At post-emergence rates of 150 g AI ha-1 or less, mesotrione provides naturally selective control of key species that may show triazine resistance (TR), e.g. Chenopodium album L, Amaranthus species, Solanum nigrum L, as well as species of weed that show resistance to acetolactase synthase (ALS) inhibitors e.g. Xanthium strumarium L, Amaranthus spp and Sonchus spp. The data presented show that resistant and susceptible biotypes of these species with resistance to triazine herbicides, such as atrazine, simazine, terbutylazine and metribuzin, or ALS-inhibitor herbicides, such as imazethepyr, remain susceptible to mesotrione. These results confirm that there is no cross-resistance in biotypes with target site resistance to triazine or ALS-inhibiting herbicides. It is important that herbicide choice and rotation becomes an integral part of planning weed management, so as to minimise the risks of crop losses from weed competition, build-up of weed seed in the soil and the further development of weed resistance across a range of herbicide modes of action.

  5. Pendimethalin aplicado à casca de arroz e serragem para o controle de plantas daninhas em Ixora chinensis Lam. Pendimethalin applied on rice husks and sawdust for weed control on Ixora chinensis Lam

    Directory of Open Access Journals (Sweden)

    André Luis Seixas

    2011-08-01

    Full Text Available A aplicação de herbicidas residuais à coberturas mortas pode aumentar a eficiência desses materiais no manejo da comunidade infestante. Objetivou-se, com este trabalho, avaliar a possibilidade de aplicação do pendimethalin à casca de arroz e à serragem para o controle de plantas daninhas em Ixora chinensis. Dois experimentos foram conduzidos aplicando-se o pendimethalin às coberturas mortas através de embebição e pulverização do herbicida, variando-se também a quantidade de cobertura utilizada. As espécies de plantas daninhas que ocorreram com maior frequência foram Alternanthera tenella, Blainvillea rhomboidea, Cenchrus echinatus e Commelina benghalensis. Há possibilidade de aplicação do herbicida pendimethalin à palha de arroz ou à serragem para controle de plantas daninhas em I. chinensis, principalmente quando ocorrem chuvas regulares e bem distribuídas. Há evidências de que a embebição da cobertura morta no herbicida seja um pouco mais eficiente no controle das plantas daninhas que a sua pulverização sobre a cobertura. Possivelmente, a quantidade de cobertura morta utilizada influencia na eficiência de controle, apesar deste fato não ter ficado claro neste trabalho.Applying herbicides at mulches may increase the efficiency of these materials for weed management. The objective of this research was to evaluate the possibility of pendimethalin applied on rice husks and sawdust for weed control on Ixora chinensis. In two field trials, pendimethalin was applied to the mulches through imbibition and spraying herbicide, also varying the amount of mulches. Higher frequent weeds were Alternanthera tenella, Blainvillea rhomboidea, Cenchrus echinatus and Commelina benghalensis. There are possibility of pendimethalin application on rice husks or sawdust for controlling weeds in I. chinensis mainly when regular and well-distributed rainfalls occur. There are evidences that the imbibition of these mulches to the herbicide

  6. Controle de plantas daninhas com herbicidas na cultura do feijão (Phaseolus vulgaris L. Weed control in beans (Phaseolus vulgaris L. with herbicides

    Directory of Open Access Journals (Sweden)

    L.S.P. Cruz

    1981-12-01

    Full Text Available Foi realizada uma pesquisa em 1970, para se conhecer os efeitos de três herbicidas aplicados em pré-plantio incorporado (EPTC a 3,60 kg/ha, nitralin e trifluralin a 0,76 kg/ha e de um em pré-emergência (fluorodifen a 3,00 kg/ha na cultura de feijão comparados com uma testemunha sem herbicida. As duas gramíneas presentes no ensaio, Eleusine indica (L. Gaertn. e Digitaria sanguinalis (L. Scop. foram eficientemente controladas por todos os herbicidas, com indices de controle superiores a 87,00%, em contagem de plantas daninhas realizada 29 dias após a aplicação dos herbicidas. Dentre as dicotiledóneas presentes, Amaranthus viridis L. também foi eficientemente controlado por todos os herbicidas, com indices de controle superiores a 92,00%. Ageratum conyzoides L. foi eficientemente controlado por fluorodifen (91,60% e regularmente por EPTC (78,99% e por nitralin (79,83%. Trifluralin não foi eficiente contra A. conyzoides L. Nenhum dos herbicidas testados controlou Ipomoea sp e Chenopodium ambrosioides L., também presentes no experimento. EPTC e nitralin apresentaram as menores porcentagens de infestação geral de plantas daninhas, tendo, aos 51 dias da aplicação dos produtos, quando suas parcelas foram capinadas mecanicamente, 8,00 e 17,00% de infestação, respectivamente. Trifluralin e fluorodifen precisaram de limpeza aos 42 dias da aplicação, e a testemunha já aos 29 dias, pois apresentavam parcelas com 25,00%, ou mais, de infestação, naquelas épocas. Os herbicidas experimentados não foram prejudiciais à germinação e ao desenvolvimento vegetativo dos feijoeiros, assim como à sua produção de grãos.The weed control with herbicides in beans crop was studied during 1970 year, in Campinas-SP, on a sandy-loam soil. The treatments employed were EPTC at 3.60 kg/ha, nitralin and trifluralin at 0.76 kg/ha, all applied in preplant i •porated; fluorodifen in preemergence at 3.00 kg/ha and a hoed check. Among the weeds

  7. Global perspective of herbicide-resistant weeds.

    Science.gov (United States)

    Heap, Ian

    2014-09-01

    Two hundred and twenty weed species have evolved resistance to one or more herbicides, and there are now 404 unique cases (species × site of action) of herbicide-resistant weeds globally. ALS inhibitor-resistant weeds account for about a third of all cases (133/404) and are particularly troublesome in rice and cereals. Although 71 weed species have been identified with triazine resistance, their importance has dwindled with the shift towards Roundup Ready® crops in the USA and the reduction of triazine usage in Europe. Forty-three grasses have evolved resistance to ACCase inhibitors, with the most serious cases being Avena spp., Lolium spp., Phalaris spp., Setaria spp. and Alopecurus myosuroides, infesting more than 25 million hectares of cereal production globally. Of the 24 weed species with glyphosate resistance, 16 have been found in Roundup Ready® cropping systems. Although Conyza canadensis is the most widespread glyphosate-resistant weed, Amaranthus palmeri and Amaranthus tuberculartus are the two most economically important glyphosate-resistant weeds because of the area they infest and the fact that these species have evolved resistance to numerous other herbicide sites of action, leaving growers with few herbicidal options for their control. The agricultural chemical industry has not brought any new herbicides with novel sites of action to market in over 30 years, making growers reliant on using existing herbicides in new ways. In addition, tougher registration and environmental regulations on herbicides have resulted in a loss of some herbicides, particularly in Europe. The lack of novel herbicide chemistries being brought to market combined with the rapid increase in multiple resistance in weeds threatens crop production worldwide. © 2013 Society of Chemical Industry.

  8. A New Hoe Blade for Inter-Row Weeding

    DEFF Research Database (Denmark)

    Green, O.; Znova, L.; Melander, Bo

    2016-01-01

    , for example uncontrollable sideward soil movement causing injurious coverage of crop plants. Based on feedbacks from researchers and practioners, a new device has been designed to overcome most of the problems associated with ‘Ducksfoot’ blades. The device consists of a stiff shank mounted on a curved VCO......New camera-based systems for automatic steering of inter-row cultivators have made it possible to conduct inter-row weeding in small inter-row spaces at reasonable work rates. This has motivated organic growers to shift from full-width weed harrowing of small grain cereals to inter-row hoeing....... The aim is mainly to improve weeding effectiveness against tall-growing and tap-rooted weed species. The ‘Ducksfoot’ hoe blade is commonly used for traditional inter-row weeding in row crops such as sugar beets and maize. This blade usually provides satisfactory weed control, if soils are not too wet...

  9. Weed seed predation in organic and conventional fields

    DEFF Research Database (Denmark)

    Navntoft, S; Wratten, S D; Kristensen, K;

    2009-01-01

    Enhanced biological control of weed seeds may improve sustainability of agricultural production. Biological control due to seed predation may be higher in organic fields because organic production generally supports more seed predators. To investigate such a difference, weed seed predation was st...

  10. Weeds in Asparagus Plantations in Hainan and Their Control Techniques%海南芦笋园杂草种类调查及杂草防除技术研究

    Institute of Scientific and Technical Information of China (English)

    李晓霞; 黄乔乔; 易克贤; 范志伟; 沈奕德; 程汉亭

    2014-01-01

    A syste matica l investigation of weeds was conducted in asparagus plantation of Hainan Province, and the dominant weed populations were determined. Then, weed control experiments were conducted. The results showed that there were 106 weed species belonging to 23 families in the asparagus garden. Of them, nine species were considered as dominant weeds, including Melinis repens, Panicum maximum, Imperata cylindrica, Digitaria setigera, Chromolaena odorata, Praxelis clematidea, Tridax procumbens and Mimosa pudica. Of the weed control strategies, coverage control and chemical control could control weeds to a certain degree:after 60d covering of nine plants, the control effect reached more than 60%. Covering the weed by cocered Pueraria lobata, Calopogonium mucunoides, Eupatorium odoratum, Mikania micrantha and Tithonia diversifolia increased the shoot number and the diameter of new shoots of asparagus. After application of four kinds of herbicides 60 d, Haloxyfop and acetochlor could control the weeds to a higher extent and were also safe to asparagus plants. In actual production practices, combining the covering and chemical weed control could control weeds to the maximum extent in the asparagus plantation.%系统调查海南芦笋种植区的主要杂草种类,明确芦笋园的杂草优势种群,并以此为基础进行盆栽芦笋化学除草药效试验及覆盖控草试验。结果表明,海南芦笋园常见杂草有21科106种,其中优势种群由马齿苋、红尾翎、短颖马唐、龙爪茅、牛筋草、砖子苗、假臭草、伞房花耳草及鳢肠9种构成。采用覆盖控草和化学除草可在一定程度上控制杂草的发生:覆盖9种植物60 d后,防效可达60%以上,且覆盖葛藤、毛蔓豆、飞机草、薇甘菊、肿柄菊后,芦笋抽笋数和新笋径围都显著高于其余各处理;施用4种除草剂60 d后,盖草能和乙草胺对盆栽芦笋的防效较高且安全。因此,在实际生产中,通过

  11. Weed management in transplanted lettuce with Pendimethalin and S-metolachlor

    Science.gov (United States)

    Few herbicides are available for use in lettuce and hand weeding is required for commercially acceptable weed control. More effective herbicides are needed. Here we report field evaluations of pendimethalin and S-metolachlor for weed control in transplanted lettuce. Pendimethalin was evaluated PRE a...

  12. Soil organic carbon stocks in coffee plantations under different weed control systemsEstoques de carbono orgânico do solo em cafezais sob diferentes sistemas de controle de plantas invasoras

    Directory of Open Access Journals (Sweden)

    Franciane Diniz Cogo

    2013-06-01

    Full Text Available Soil organic carbon (COS is an important indicator of soil quality, as its levels and stocks can change by soil preparation. This study aimed to evaluate COS stocks on a clayey Oxisol cultivated with coffee and subject to different weed control systems in southern Minas Gerais, Brazil. The experimental design was in randomized blocks, and weed control systems were: no weeding, manual weeding, pre-emergence herbicide, post-emergence herbicide, rotary tiller, rotary mowers and disk harrow. Undisturbed soil samples were collected at two positions in the coffee plantation (tire tracks and planting line, at depths of 0-3, 10-13, and 25-28 cm. A nearby native forest was sampled as a reference. A higher bulk density of soils under coffee plantations occurred compared to soil under the forest. There was little difference between COS concentrations in the plating line in relation to the native forest, but for the tire track position, the amount of COS was generally lower. After correction for soil compaction, it was estimated a loss of ca. 20% in SOC stock for te 0-30 cm depth for herbicide post-emergence, rotary tiller, manual weeding and disk barrow, and a 35% loss when using herbicide pre-emergence. SOC stocks under no weeding and rotary mowers did not differ from native forest (37 M-1g ha COS, indicating that the rotary mower, which allows temporary growth of weeds and does not disrupt soil structure, is the most appropriate weed control for the preservation of COS in coffee plantations.O carbono orgânico no solo (COS é um importante indicador da qualidade do solo, pois seus teores e estoques podem ser alterados conforme o sistema de preparo do solo. Objetivou-se neste trabalho avaliar os estoques de COS em um Latossolo Vermelho distroférrico argiloso cultivado com cafeeiros (Coffea arabica L e submetido a diferentes manejos de plantas invasoras no sul de Minas Gerais. O delineamento experimental foi em blocos ao acaso, sendo os tratamentos os

  13. Métodos de controle de plantas invasoras na cultura do cafeeiro (Coffea arabica L. e componentes da acidez do solo Weed control methods and soil acidity components in coffee plantation (Coffea arabica L.

    Directory of Open Access Journals (Sweden)

    Elifas Nunes Alcântara

    2007-12-01

    Full Text Available Em lavouras perenes, como na cultura do cafeeiro, o controle de plantas invasoras tem sido feito por meio de métodos manuais, mecanizados, químicos e associações destes. De modo geral, têm-se avaliado os diferentes métodos sob o ponto de vista de eficiência e de custo no controle das plantas invasoras; no entanto, a influência deles sobre as condições químicas do solo, praticamente, não tem sido estudada, principalmente a longo prazo. O objetivo deste estudo foi avaliar o efeito de diferentes métodos de controle de plantas invasoras na cultura do cafeeiro sobre os componentes da acidez de um Latossolo Vermelho distroférrico da região de São Sebastião do Paraíso, MG. Sete tratamentos de controle de plantas invasoras foram avaliados: roçadora (RÇ, grade (GR, enxada rotativa (RT, herbicida de pós-emergência (HC, herbicida de pré-emergência (HR, capina manual (CM e testemunha sem capina (SC, dispostos em blocos casualizados com três repetições. Amostras de solo, em cada tratamento, foram coletadas a cada dois anos, a partir de 1980, nas camadas de 0-0,15 e 0,15-0,30 m, para avaliação de pH, Al3+, acidez potencial (H + Al e saturação por Al3+ (m. O sistema HR aumentou o teor e a saturação por Al3+ e a acidez potencial e diminuiu o pH, quando comparado com os demais métodos de controle de plantas invasoras, principalmente com a testemunha (SC. O tratamento SC mostrou efeito contrário ao do HR, aumentando os valores de pH e diminuindo o teor de Al3+ e a saturação por Al3+, em ambas as camadas de solo. O RÇ foi o tratamento que mais se aproximou do SC, e os demais tratamentos, no geral, não apresentaram comportamento diferenciado.In perennial agriculture, such as coffee plantation, weeds are controlled by hand, mechanized, and chemical weeding and their combinations. Methods that differ in terms of efficiency and costs have been evaluated; however, the influence of these methods on the soil chemical conditions has

  14. Eficiência do triclopyr no controle de plantas daninhas em gramado (Paspalum notatum Triclopyr efficiency in controlling weeds in the lawn (Paspalum notatum

    Directory of Open Access Journals (Sweden)

    F.C.L. Freitas

    2003-04-01

    Full Text Available As plantas daninhas interferem nos gramados, prejudicando a sua formação, qualidade e estética. O carrapicho-beiço-de-boi (Desmodium incanum e a zórnia (Zornia latifolia, quando não controlados, podem atingir níveis de infestação que chegam a dizimar o gramado. Dentre as diversas técnicas de manejo de plantas daninhas em gramados, destaca-se o emprego de herbicidas; todavia, as informações sobre a utilização desses produtos em gramados são escassas. O objetivo deste trabalho foi avaliar a eficiência do herbicida triclopyr no controle de Desmodium incanum e Zornia latifolia, infestantes da grama-batatais (Paspalum notatum. O trabalho foi desenvolvido em gramado estabelecido no campus da Universidade Federal de Viçosa, em Viçosa-MG, entre os meses de abril e maio de 2000. Os tratamentos avaliados foram seis doses do triclopyr (0,00; 0,24; 0,48; 0,72; 0,96; e 1,20 kg ha-1 e uma dose do 2,4-D + picloram (0,48 + 0,128 kg ha-1, dispostos em delineamento experimental com blocos ao acaso e quatro repetições. O tamanho de cada parcela foi de 12 m² (4,0 x 3,0 m, sendo os tratamentos aplicados em uma faixa de 2,0 m de largura, ficando 1,0 m como testemunha lateral, para auxiliar nas avaliações visuais. Foram realizadas avaliações de fitotoxicidade aos 10 e 20 DAT (Dias Após o Tratamento e nível de controle aos 15 e 30 DAT, ambos com base na testemunha lateral. Em nenhum dos tratamentos avaliados verificaram-se danos na qualidade do gramado. A partir das doses de 0,48 e 0,66 kg ha-1 de triclopyr foram obtidos controles iguais ou superiores a 90% de Desmodium incanum e Zornia latifolia, respectivamente. Esses resultados foram semelhantes ao do tratamento-padrão (2,4D + picloram a 0,48 + 0,128 kg ha-1. Concluiu-se que o triclopyr mostrou-se seletivo para grama-batatais, proporcionando excelente controle das plantas daninhas acima mencionadas.Weeds interfere in the formation, quality and aesthetics of the lawn. Desmodium incanum

  15. Application of poly(epsilon-caprolactone) nanoparticles containing atrazine herbicide as an alternative technique to control weeds and reduce damage to the environment.

    Science.gov (United States)

    Pereira, Anderson E S; Grillo, Renato; Mello, Nathalie F S; Rosa, Andre H; Fraceto, Leonardo F

    2014-03-15

    Nanoparticles of poly(epsilon-caprolactone) containing the herbicide atrazine were prepared, characterized, and evaluated in terms of their herbicidal activity and genotoxicity. The stability of the nanoparticles was evaluated over a period of three months, considering the variables: size, polydispersion index, pH, and encapsulation efficiency. Tests on plants were performed with target (Brassica sp.) and non-target (Zea mays) organisms, and the nanoparticle formulations were shown to be effective for the control of the target species. Experiments using soil columns revealed that the use of nanoparticles reduced the mobility of atrazine in the soil. Application of the Allium cepa chromosome aberration assay demonstrated that the nanoparticle systems were able to reduce the genotoxicity of the herbicide. The formulations developed offer a useful means of controlling agricultural weeds, while at the same time reducing the risk of harm to the environment and human health. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Microwave Technologies as Part of an Integrated Weed Management Strategy: A Review

    Directory of Open Access Journals (Sweden)

    Graham Brodie

    2012-01-01

    Full Text Available Interest in controlling weed plants using radio frequency or microwave energy has been growing in recent years because of the growing concerns about herbicide resistance and chemical residues in the environment. This paper reviews the prospects of using microwave energy to manage weeds. Microwave energy effectively kills weed plants and their seeds; however, most studies have focused on applying the microwave energy over a sizable area, which requires about ten times the energy that is embodied in conventional chemical treatments to achieve effective weed control. A closer analysis of the microwave heating phenomenon suggests that thermal runaway can reduce microwave weed treatment time by at least one order of magnitude. If thermal runaway can be induced in weed plants, the energy costs associated with microwave weed management would be comparable with chemical weed control.

  17. Cultivos intercalares e controle de plantas daninhas em plantios de maracujá-amarelo Intercropping and weed control in yellow passion fruit orchard

    Directory of Open Access Journals (Sweden)

    Adelise de Almeida Lima

    2002-12-01

    Full Text Available Objetivou-se identificar cultivos intercalares e métodos integrados de controle de plantas daninhas em maracujá-amarelo (Passiflora edulis Sims f. flavicarpa Deg. como fatores que viabilizem a sua produção e rentabilidade. O experimento foi instalado em maio de 1999, conduzido em espaldeira vertical com um fio de arame a 2,0m do solo, no espaçamento de 2,5m x 5,0m, em blocos casualizados, com seis tratamentos e quatro repetições, sendo T1: milho (Zea mays L. - BR 106 como cultura intercalar; T2: feijão (Phaseolus vulgaris L. - cultivar Pérola como cultura intercalar; T3: feijão-de-porco nas entrelinhas e capina com enxada nas linhas; T4: feijão-de-porco nas entrelinhas e controle químico nas linhas (glifosate a 1,5 kg/ha; T5: planta daninha controlada quimicamente (em toda a parcela com alachlor a 2,8 kg/ha + diuron a 1,2 kg/ha em pré-emergência e glifosate a 1,5 kg/ha em pós-emergência; e T6: testemunha (capina com enxada em área total. Os dados analisados, no período de produção (maio de 1999 a abril de 2000, mostraram que não houve diferenças estatísticas entre os tratamentos para produtividade (indústria, peso médio, comprimento e diâmetro dos frutos, sólidos solúveis totais e acidez. Contudo, houve significância para produtividade total e in natura, com destaque para a utilização do feijão como cultura intercalar, com produtividade do maracujazeiro de 12,82 t/ha. Tanto o milho como o feijão podem ser recomendados como culturas intercalares no primeiro ano de cultivo do maracujá-amarelo. Os herbicidas aplicados em pré e pós-emergência foram economicamente viáveis e não mostraram efeito tóxico sobre as plantas de maracujá-amarelo.This work aimed identifying crops for intercropping and integrated methods for weed control in yellow passion fruit (Passiflora edulis Sims f. flavicarpa Deg. orchard, that will favor its production and profitability. The experiment was set up in May 1999, with the plants

  18. The Politics of Weeding.

    Science.gov (United States)

    Tillman, Hope N.

    1988-01-01

    Reviews the literature that deals with the political ramifications of weeding material from academic library collections and the need to involve users and other libraries within the institution in the decision process. (14 references) (CLB)

  19. Influence of corn sowing density and gliricidia intercropping on weed control Influências da densidade de semeadura do milho e da consorciação com gliricídia sobre o controle de plantas daninhas

    Directory of Open Access Journals (Sweden)

    P.S.L. Silva

    2010-06-01

    Full Text Available There is interest in the identification of the best seeding density for new corn hybrids and on reduced use of herbicides for weed control. The objective of this study was to evaluate the effects of seeding density (30, 50, 70, and 90 thousand plants ha-1 and weed control on green ear yield and grain yield in corn cultivar AG 1051. A completely randomized block design was adopted with split-plots (seeding densities assigned to plots and ten replicates. Weed control was achieved by means of two hoeings and by planting corn intercropped with gliricidia (between corn rows, in pits spaced 0.3 m apart. A "no weeding"treatment was included as well. Increased seeding density increased the total number and weight of marketable green ears and decreased the biomass of both weeds and gliricidia. In non-weeded, intercropped and hoed plots, the maximum grain yield values achieved as seeding density increased were 7,881, 7,021, and 9,213 kg ha-1, respectively, obtained with populations of 67 thousand, 74 thousand, and 67 thousand plants per hectare, respectively. Intercropping did not control weeds (26 species and provided weed growth, green ear yield, and grain yield (at the lowest densities similar to those obtained without hoeing, except for total number of green ears, in which no influence of weed control was observed. At densities of 70 thousand and 90 thousand plants per hectare, grain yield with two hoeings was not different from yield values obtained without weeding or in the treatment intercropped with gliricidia, respectively, indicating that increased corn seeding density as well as gliricidiamay help to control weeds.Existe interesse na identificação da densidade de semeadura ideal para os novos híbridos de milho e na redução do uso de herbicidas no controle de plantas daninhas. O objetivo deste trabalho foi avaliar os efeitos da densidade de semeadura (30, 50, 70 e 90 mil plantas ha-1 e do controle de plantas daninhas sobre os rendimentos de

  20. Robotic weed monitoring

    DEFF Research Database (Denmark)

    Bochtis, Dionysis; Sørensen, Claus Aage Grøn; Jørgensen, R N

    2011-01-01

    -farm operating console, the mobile robotic unit, and a field server for generating and storingmaps. The hypothesis is that it is possible to automate the planning and execution of theoperation of monitoring of the in-field weed density and species distribution. The developedplanning system includes the automatic...... of the weed monitoring operation.Key words: autonomous vehicles, farm management, mission planning, route planning,sampling....

  1. Female sex pheromone secreted by Carmenta mimosa (Lepidoptera: Sesiidae), a biological control agent for an invasive weed in Vietnam.

    Science.gov (United States)

    Vang, Le Van; Khanh, Chau Nguyen Quoc; Shibasaki, Hiroshi; Ando, Tetsu

    2012-01-01

    Larvae of the clearwing moth, Carmenta mimosa (Lepidoptera: Sesiidae), bore into the trunk of Mimosa pigra L., which is one of the most invasive weeds in Vietnam. GC-EAD and GC-MS analyses of a pheromone gland extract revealed that the female moths produced (3Z,13Z)-3,13-octadecadienyl acetate. A lure baited with the synthetic acetate alone successfully attracted C. mimosa males in a field test. While the addition of a small amount of the corresponding alcohol did not strongly diminish the number of captured males, a trace of the aldehyde derivative or the (3E,13Z)-isomer markedly inhibited the attractiveness of the acetate. The diurnal males were mainly attracted from 6:00 am to 12:00 am.

  2. Seletividade e controle de plantas daninhas com oxyfluorfen e sulfentrazone na implantação de lavoura de café Weed selectivity and control with oxyfluorfen and sulfentrazone in young arabica coffee plantations

    Directory of Open Access Journals (Sweden)

    C.E.O. Magalhães

    2012-09-01

    Full Text Available Este trabalho teve por objetivo avaliar a seletividade do oxyfluorfen e do sulfentrazone e o controle de plantas daninhas em diferentes épocas após o transplantio das mudas de café no campo. Foram realizados três ensaios no delineamento experimental de blocos casualizados com dez tratamentos e quatro repetições. No ensaio 1, aos 30 dias após o transplantio (DAT e, no ensaio 2, aos 90 DAT, testaram-se duas doses de oxyfluorfen (0,36 e 0,72 kg i.a. ha-1 e de sulfentrazone (0,4 e 0,6 kg i.a. ha-1, em jato dirigido ao solo (com proteção das mudas e em área total. No ensaio 3, os mesmos herbicidas e doses foram aplicados, porém aos 300 DAT e apenas em aplicação dirigida, testando-se duas pontas de pulverização de diferentes potenciais de deriva. Em todos os ensaios, acrescentaram-se as testemunhas capinada e sem capina. A entrelinha foi manejada com roçada. Foram identificadas as espécies de plantas daninhas e suas densidades. A eficácia dos herbicidas e suas seletividades também foram avaliadas. A principal planta daninha que ocorreu na área experimental foi Brachiaria decumbens. Sintomas visuais de toxicidade foram observados apenas quando os herbicidas foram aplicados em área total (ensaios 1 e 2, independentemente da dose e época de aplicação. No ensaio 3, independentemente do herbicida, da dose e da ponta utilizada, não houve sintomas visuais de toxicidade, nem redução no crescimento das plantas, em função da aplicação dirigida. Em todas as épocas o controle de plantas daninhas foi eficiente, porém a seletividade só foi alcançada na aplicação dirigida, para ambos os herbicidas.This study aimed to evaluate oxyfluorfen and sulfentrazone selectivity and weed control in young coffee plantations (Coffea arabica cv. Red Catuaí. Three trials were conducted in a randomized complete block design, with 10 treatments and four replicates. In the first and second trials, at 30 and 90 days after transplanting (DAT

  3. Can Arbuscular Mycorrhizal Fungi Reduce the Growth of Agricultural Weeds?

    Science.gov (United States)

    Veiga, Rita S. L.; Jansa, Jan; Frossard, Emmanuel; van der Heijden, Marcel G. A.

    2011-01-01

    Background Arbuscular mycorrhizal fungi (AMF) are known for their beneficial effects on plants. However, there is increasing evidence that some ruderal plants, including several agricultural weeds, respond negatively to AMF colonization. Here, we investigated the effect of AMF on the growth of individual weed species and on weed-crop interactions. Methodology/Principal Findings First, under controlled glasshouse conditions, we screened growth responses of nine weed species and three crops to a widespread AMF, Glomus intraradices. None of the weeds screened showed a significant positive mycorrhizal growth response and four weed species were significantly reduced by the AMF (growth responses between −22 and −35%). In a subsequent experiment, we selected three of the negatively responding weed species – Echinochloa crus-galli, Setaria viridis and Solanum nigrum – and analyzed their responses to a combination of three AMF (Glomus intraradices, Glomus mosseae and Glomus claroideum). Finally, we tested whether the presence of a crop (maize) enhanced the suppressive effect of AMF on weeds. We found that the growth of the three selected weed species was also reduced by a combination of AMF and that the presence of maize amplified the negative effect of AMF on the growth of E. crus-galli. Conclusions/Significance Our results show that AMF can negatively influence the growth of some weed species indicating that AMF have the potential to act as determinants of weed community structure. Furthermore, mycorrhizal weed growth reductions can be amplified in the presence of a crop. Previous studies have shown that AMF provide a number of beneficial ecosystem services. Taken together with our current results, the maintenance and promotion of AMF activity may thereby contribute to sustainable management of agroecosystems. However, in order to further the practical and ecological relevance of our findings, additional experiments should be performed under field conditions. PMID

  4. 几种除草剂防除玉米田杂草的田间药效对比%Control Effect of Five Herbicides on Weeds in Maize Field

    Institute of Scientific and Technical Information of China (English)

    刘毅; 王承星; 张卫书; 覃移洋

    2012-01-01

    The control effect of five herbicides on weeds in maize field was studied to select the optimal herbicides for controlling weeds in maize field and promoting efficient and safety production of maize. The results showed that the control effect of 40 % Cyanazine SC and 23 % Ethyl Atrazine SC on monocotyledonous and dicotyledonous weeds in maize field was 90. 76% and 91. 60% respectively. 40% Cyanazine SC and 23% Ethyl Atrazine SC with the wide weeding range and longer validity period are the optimal herbicides in maize cultivation.%为选择能防除玉米田杂草且对玉米安全的理想除草剂,促进玉米高效安全生产,对40%乙·莠·氰草津SC、15%甲基磺草酮SC等5种除草剂进行玉米田杂草防除药效试验.结果表明:40%乙·莠·氰草津SC、23%烟嘧·莠去津SC对玉米田单、双子叶杂草有较好的防效,防治效果分别选90.76%、91.60%.两种除草剂杀草谱广,持效期长,对玉米苗安全,是理想的玉米地除草剂.

  5. Emerging Challenges and Opportunities for Education and Research in Weed Science.

    Science.gov (United States)

    Chauhan, Bhagirath S; Matloob, Amar; Mahajan, Gulshan; Aslam, Farhena; Florentine, Singarayer K; Jha, Prashant

    2017-01-01

    In modern agriculture, with more emphasis on high input systems, weed problems are likely to increase and become more complex. With heightened awareness of adverse effects of herbicide residues on human health and environment and the evolution of herbicide-resistant weed biotypes, a significant focus within weed science has now shifted to the development of eco-friendly technologies with reduced reliance on herbicides. Further, with the large-scale adoption of herbicide-resistant crops, and uncertain climatic optima under climate change, the problems for weed science have become multi-faceted. To handle these complex weed problems, a holistic line of action with multi-disciplinary approaches is required, including adjustments to technology, management practices, and legislation. Improved knowledge of weed ecology, biology, genetics, and molecular biology is essential for developing sustainable weed control practices. Additionally, judicious use of advanced technologies, such as site-specific weed management systems and decision support modeling, will play a significant role in reducing costs associated with weed control. Further, effective linkages between farmers and weed researchers will be necessary to facilitate the adoption of technological developments. To meet these challenges, priorities in research need to be determined and the education system for weed science needs to be reoriented. In respect of the latter imperative, closer collaboration between weed scientists and other disciplines can help in defining and solving the complex weed management challenges of the 21st century. This consensus will provide more versatile and diverse approaches to innovative teaching and training practices, which will be needed to prepare future weed science graduates who are capable of handling the anticipated challenges of weed science facing in contemporary agriculture. To build this capacity, mobilizing additional funding for both weed research and weed management

  6. Herbicide-resistant weed management: focus on glyphosate.

    Science.gov (United States)

    Beckie, Hugh J

    2011-09-01

    This review focuses on proactive and reactive management of glyphosate-resistant (GR) weeds. Glyphosate resistance in weeds has evolved under recurrent glyphosate usage, with little or no diversity in weed management practices. The main herbicide strategy for proactively or reactively managing GR weeds is to supplement glyphosate with herbicides of alternative modes of action and with soil-residual activity. These herbicides can be applied in sequences or mixtures. Proactive or reactive GR weed management can be aided by crop cultivars with alternative single or stacked herbicide-resistance traits, which will become increasingly available to growers in the future. Many growers with GR weeds continue to use glyphosate because of its economical broad-spectrum weed control. Government farm policies, pesticide regulatory policies and industry actions should encourage growers to adopt a more proactive approach to GR weed management by providing the best information and training on management practices, information on the benefits of proactive management and voluntary incentives, as appropriate. Results from recent surveys in the United States indicate that such a change in grower attitudes may be occurring because of enhanced awareness of the benefits of proactive management and the relative cost of the reactive management of GR weeds.

  7. 不同浓度下两种除草剂对羊草草原杂草防除效果的研究%Control Effect of Two Herbicides Different Doses on Weeds in Leymus chinensis Grassland

    Institute of Scientific and Technical Information of China (English)

    高超; 张月学; 陈积山; 邸桂俐; 潘多锋; 王建丽; 张强

    2015-01-01

    In order to control the weeds of degraded grassland and promote grassland stable high yield and sus-tainable utilization ,three dose levels of two herbicides (72% 2 ,4-D butylate EC and 48% bentazone aqueous solution) were used for the weed control test in Leymus chinensis grassland .The results showed that 2 ,4-D butylate and bentazone were safe to forage grass .When the concentration of 2 ,4-D butylate was 1 458 mL·hm-2 ,the weed control efficacy and strains fresh weight was excellent .Cirsium setosum could be controlled better when the concentration of bentazone was 5 400 mL·hm-2 .In practice ,combined with the dis-tribution situation of weed ,the two herbicides could be mixed to improve the weeds control effect .%为了治理退化草原的杂草 ,促进草地稳产、高产和可持续利用 ,用两种除草剂(72% 的2 ,4-D丁酯和48% 灭草松水剂)3个不同剂量浓度对羊草草原的杂草进行防除试验.结果表明 :2 ,4-D丁酯和灭草松除草剂对羊草草原可饲牧草安全无害.2 ,4-D丁酯除草剂施用浓度为1 458 mL·hm-2时 ,杂草株防效和鲜重防效均较高 ,灭草松施用浓度为5 400 mL·hm-2时对刺菜株防效较好 ,在实际应用中可结合杂草分布情况混合复配两种除草剂提高杂草防除效果.

  8. Analysis of Satellite and Airborne Imagery for Detection of Water Hyacinth and Other Invasive Floating Macrophytes and Tracking of Aquatic Weed Control Efficacy

    Science.gov (United States)

    Potter, Christopher

    2016-01-01

    Waterways of the Sacramento San Joaquin Delta have recently become infested with invasive aquatic weeds such as floating water hyacinth (Eichhoria crassipes) and water primrose (Ludwigia peploides). These invasive plants cause many negative impacts, including, but not limited to: the blocking of waterways for commercial shipping and boating; clogging of irrigation screens, pumps and canals; and degradation of biological habitat through shading. Zhang et al. (1997, Ecological Applications, 7(3), 1039-1053) used NASA Landsat satellite imagery together with field calibration measurements to map physical and biological processes within marshlands of the San Francisco Bay. Live green biomass (LGB) and related variables were correlated with a simple vegetation index ratio of red and near infra-red bands from Landsat images. More recently, the percent (water area) cover of water hyacinth plotted against estimated LGB of emergent aquatic vegetation in the Delta from September 2014 Landsat imagery showed an 80 percent overall accuracy. For the past two years, we have partnered with the U. S. Department of Agriculture (USDA) and the Department of Plant Sciences, University of California at Davis to conduct new validation surveys of water hyacinth and water primrose coverage and LGB in Delta waterways. A plan is underway to transfer decision support tools developed at NASA's Ames Research Center based on Landsat satellite images to improve Delta-wide integrated management of floating aquatic weeds, while reducing chemical control costs. The main end-user for this application project will be the Division of Boating and Waterways (DBW) of the California Department of Parks and Recreation, who has the responsibility for chemical control of water hyacinth in the Delta.

  9. An overview of plant volatile metabolomics, sample treatment and reporting considerations with emphasis on mechanical damage and biological control of weeds.

    Science.gov (United States)

    Beck, John J; Smith, Lincoln; Baig, Nausheena

    2014-01-01

    The technology for the collection and analysis of plant-emitted volatiles for understanding chemical cues of plant-plant, plant-insect or plant-microbe interactions has increased over the years. Consequently, the in situ collection, analysis and identification of volatiles are considered integral to elucidation of complex plant communications. Due to the complexity and range of emissions the conditions for consistent emission of volatiles are difficult to standardise. To discuss: evaluation of emitted volatile metabolites as a means of screening potential target- and non-target weeds/plants for insect biological control agents; plant volatile metabolomics to analyse resultant data; importance of considering volatiles from damaged plants; and use of a database for reporting experimental conditions and results. Recent literature relating to plant volatiles and plant volatile metabolomics are summarised to provide a basic understanding of how metabolomics can be applied to the study of plant volatiles. An overview of plant secondary metabolites, plant volatile metabolomics, analysis of plant volatile metabolomics data and the subsequent input into a database, the roles of plant volatiles, volatile emission as a function of treatment, and the application of plant volatile metabolomics to biological control of invasive weeds. It is recommended that in addition to a non-damaged treatment, plants be damaged prior to collecting volatiles to provide the greatest diversity of odours. For the model system provided, optimal volatile emission occurred when the leaf was punctured with a needle. Results stored in a database should include basic environmental conditions or treatments. Copyright © 2013 John Wiley & Sons, Ltd.

  10. Weed biocontrol in the EU: from serendipity to strategy

    Science.gov (United States)

    Biological control of weeds is a globally-recognized approach to the management of the worst invasive plants in the world. Unfortunately, accidental introduction of agents account for most weed biocontrol in the EU, but do include a number of current or emerging successes. From the redistribution of...

  11. Weed map generation from UAV image mosaics based on crop row detection

    DEFF Research Database (Denmark)

    Midtiby, Henrik Skov

    To control weed in a field effectively with a minimum of herbicides, knowledge about the weed patches is required. Based on images acquired by Unmanned Aerial Vehicles (UAVs), a vegetation map of the entire field can be generated. Manual analysis, which is often required, to detect weed patches...

  12. Economics of weed suppressive rice cultivars in flood- and furrow-irrigated systems

    Science.gov (United States)

    Weeds are a major constraint to rice production. In the U.S, weeds in rice are controlled primarily with synthetic herbicides. Intensive herbicide application in rice also has many potential drawbacks, resulting in environmental pollution, human health concerns, and development of weed resistance. B...

  13. Morphological traits associated with weed-suppressive ability of winter wheat against Italian ryegrass

    Science.gov (United States)

    Weed-suppressive wheat (Triticum aestivum L.) cultivars have been suggested as a complement to chemical and cultural methods of weed control. The objectives of this study were to assess the range of weed-suppressive ability against Italian ryegrass [Lolium perenne L. ssp. multiflorum (Lam.) Husnot] ...

  14. Narrow rows reduce biomass and seed production of weeds and increase maize yield

    NARCIS (Netherlands)

    Mashingaidze, A.B.; Werf, van der W.; Lotz, L.A.P.; Chipomho, J.; Kropff, M.J.

    2009-01-01

    Smallholder farmers in southern African countries rely primarily on cultural control and hoe weeding to combat weeds, but often times, they are unable to keep up with the weeding requirements of the crop because of its laboriousness, causing them to incur major yield losses. Optimisation of crop pla

  15. Critical period for weed control in potatoes in the Huambo Province (Angola Período crítico do controle de infestantes na cultura da batateira na Província do Huambo (Angola

    Directory of Open Access Journals (Sweden)

    A. Monteiro

    2011-06-01

    Full Text Available The effects of different weed management periods on potatoes were studied in three areas (Bailundo, Chianga and Calenga of the central highlands of Angola and in three cropping seasons, from June 2005 to May 2007. Six weed-management treatments were used to identify critical periods of competition and to allow the development of more precise management recommendations. Total potato yield ranged from about 22 t ha-1 in weed-free plots to about 3 t ha-1 with no weed control a yield loss of 86%. Major weed species Galinsoga parviflora, Cyperus esculentus, Bidens biternata, Amaranthus hybridus, Nicandra physaloides, Portulaca oleracea and Datura stramonium differed from area to area. The species G. parviflora dominated the weed flora in all three areas 73, 97 and 72 plants m² 50 days after crop emergence in Bailundo, Chianga and Calenga respectively, in dry season trials; while C. esculentus was also present in Chianga and Calenga, with an average density of ca 30 plants m-2 in dry season trials. Gompertz and logistic equations were fitted to data representing increasing periods of weed-free growth and weed interference, respectively. Critical periods for weed control, with a 95% weed-free total yield, were estimated from 26 to 66 and from 20 to 61 days after emergence for the rainy and dry seasons, respectively. Weed competition before or after these critical periods had negligible effects on crop yield.Com o objectivo de obter recomendações mais precisas para a gestão das infestantes na cultura da batata 'Romano' avaliou-se o efeito de diferentes períodos de controle e de convivência em três locais do Planalto Central de Angola e em três épocas de crescimento da cultura. O delineamento experimental, por local, consistiu em blocos casualizados com três repetições. Os tratamentos consistiram de seis intervalos de controle nos quais a cultura foi mantida livre de infestantes e após cada período estas foram deixadas crescer livremente; e

  16. 2种药剂防除麦田禾本科杂草-雀麦试验%Experiment on Grass Weed-Bromusjaponicus Control in Winter Wheat Filed by Two Herbicides

    Institute of Scientific and Technical Information of China (English)

    陈秀双; 韩关华

    2012-01-01

    以雀麦为主的麦田禾本科杂草在故城县呈上升发展势头。由于防治时期、防治药剂受限,致使麦田禾本科杂草的防除成了生产中的一大难题。为筛选防除麦田禾本科杂草的有效药剂,2010年秋季进行了田间药效试验。结果表明:氟唑磺隆70%水分散粒剂和甲基二磺隆30g/L油悬浮剂对麦田禾本科杂草—雀麦均具有较好的防除效果。%The damage of grass weeds, especially Bromus japonicus, become more and more serious in winter wheat filed in Gucheng County. It was a big problem for grass weeds manage- ment because of the restriction of optimum control time and available herbicides. In order to screen effective herbicides against grass weeds, filed experiment was conducted at the autumn of 2010. The results showed that flucarbazone 70%WDG and mesosulfuron-methyl 30g/L OF were effective herbicides for grass weeds-Bromus japonicus control.

  17. Aumento da população de plantas e uso de herbicidas no controle de plantas daninhas em milho Increase of plant population and use of herbicides to control weeds in corn

    Directory of Open Access Journals (Sweden)

    Aldo Merotto Junior

    1997-01-01

    Full Text Available O objetivo deste trabalho foi determinar a capacidade de controle de plantas daninhas efetuada pelo aumento da população de plantas de milho em associação com diferentes métodos de controle de plantas daninhas. O experimento foi conduzido em Lages (SC sob o delineamento de blocos ao acaso em parcelas subdivididas. Nas parcelas principais foram alocados os métodos de controle de plantas daninhas: 1 sem controle; 2 atrazine + metolachlor (1,4 + 2,1 kg/h a em pré emergência; 3 nicosulfuron (60 g/ ha em pós - emergência; 4 atrazine + metolachlor em pré emergência e nicosulfuron em pós-emergência; e 5 capina até o florescimento. Nas sub parcelas foram alocadas as populações de plantas: 35.000, 50.000, 68.000 e 80.000 plantas ha-1. O aumento da população de plantas foi mais efetivo na diminuição da matéria seca de plantas daninhas nos tratamentos sem controle e com herbicida em pré emergência. As plantas daninhas promoveram maiores decréscimos no rendimento de grão s de milho na população de 80000 plantas ha-1, onde a competição com plantas daninhas somou-se à competição intraespecífica que também é maior do que nas menores populações . O uso de altas populações de plantas diminui a competição com plantas daninhas , mas deve ser complementado com outros métodos de controle no início do desenvolvimento da cultura.The objective of this experiment was to evaluate the effectiveness of increasing corn plant population in association with differe nt methods to control weeds. The trial was conduted in Lages, SC, using a randomized complete block desing in a split plot arragement. Fiv e methods of weed control were located at the main plots: 1 check without control, 2 atrazine + metolachlor (1,4 + 2,1 kg/ha in pre-emergency, 3 nicosulfuron (60 g/ha in post emergency, 4 atrazine + metolachlor in pre-emergency and nicosulfuron in post emergency, and 5 hoeing up to flowerin g. Four plant population were tested at split

  18. 基于多路由协议的株间锄草机器人结构和控制优化设计%Control Optimization Design and Structure of Plant Weeding Robot Based on Muti-routing Protocols

    Institute of Scientific and Technical Information of China (English)

    李伟; 江民夏; 汪小志; 余良俊

    2016-01-01

    In order to obtain the ideal effect of mechanical weeding between seedlings,it presents a new structural optimi-zation method of weeding robot.It adopts the multi-objective optimization model to design the terminal structure of wee-ding, the cooperative control of multiple weeding robot with multiple routing protocols,greatly improving the work efficien-cy of field weeding robot.Based on the established mechanical weeding tooth trajectory mathematical model, it was com-bined with the requirements of modern agriculture to the limit and mechanical weeding parameters.The multi-objective optimization model is established,and the optimization toolbox of Matlab to obtain the optimal solution and its application in multi robot routing protocol system control framework.In order to verify the validity of the optimization method,experi-ments are carried out in collaboration of multi field weeding robot, it found through experiments, the multi routing wee-ding robot after optimization,not only greatly improves the operation speed and the weeding efficiency,but also reduce the crop loss rate, which provides a theoretical basis for the design of rotary tillage weeding machine in large scale.%为获得理想的苗间机械锄草效果,提出了一种新的锄草机器人结构优化方法.该方法主要采用多目标优化模型对锄草末端结构进行设计,采用多路由协议对多锄草机器人进行协同控制,大大提高了田间锄草机器人的工作效率.在建立了机械锄草齿运动轨迹数学模型的基础上,结合现代农艺对机械锄草参数的限定及要求,建立了多目标优化模型,并利用MatLab优化工具箱得到最优解,将其应用在多机器人系统控制的多路由协议框架中.为了验证优化方法的有效性,在田间对多锄草机器人协同作业进行了试验,结果表明:优化后的多路由锄草机器人不仅大大提高了作业速度和锄草效率,而且降低了作物苗损失率,为大型中耕除

  19. Robotic intra-row weed hoeing in maize and sugar beet

    Directory of Open Access Journals (Sweden)

    Gerhards, Roland

    2016-02-01

    Full Text Available A prototype of robotic intra-row weed hoeing in maize and sugar beet is presented in this study. Weeds in the crop rows were identified using a bi-spectral image analysis system and shape analysis. Positions of weeds in the images were recorded. Selective weed control in the row was performed with a modified finger weeder driven by electrical motors. Speed of the finger weeder was increased at positions where only weeds were classified. The system was triggered by an encoder and controlled by a micro-controller.

  20. Weed Diversity Affects Soybean and Maize Yield in a Long Term Experiment in Michigan, USA.

    Science.gov (United States)

    Ferrero, Rosana; Lima, Mauricio; Davis, Adam S; Gonzalez-Andujar, Jose L

    2017-01-01

    Managing production environments in ways that promote weed community diversity may enhance both crop production and the development of a more sustainable agriculture. This study analyzed data of productivity of maize (corn) and soybean in plots in the Main Cropping System Experiment (MCSE) at the W. K. Kellogg Biological Station Long-Term Ecological Research (KBS-LTER) in Michigan, USA, from 1996 to 2011. We used models derived from population ecology to explore how weed diversity, temperature, and precipitation interact with crop yields. Using three types of models that considered internal and external (climate and weeds) factors, with additive or non-linear variants, we found that changes in weed diversity were associated with changes in rates of crop yield increase over time for both maize and soybeans. The intrinsic capacity for soybean yield increase in response to the environment was greater under more diverse weed communities. Soybean production risks were greatest in the least weed diverse systems, in which each weed species lost was associated with progressively greater crop yield losses. Managing for weed community diversity, while suppressing dominant, highly competitive weeds, may be a helpful strategy for supporting long term increases in soybean productivity. In maize, there was a negative and non-additive response of yields to the interaction between weed diversity and minimum air temperatures. When cold temperatures constrained potential maize productivity through limited resources, negative interactions with weed diversity became more pronounced. We suggest that: (1) maize was less competitive in cold years allowing higher weed diversity and the dominance of some weed species; or (2) that cold years resulted in increased weed richness and prevalence of competitive weeds, thus reducing crop yields. Therefore, we propose to control dominant weed species especially in the years of low yield and extreme minimum temperatures to improve maize yields

  1. Weed Diversity Affects Soybean and Maize Yield in a Long Term Experiment in Michigan, USA

    Science.gov (United States)

    Ferrero, Rosana; Lima, Mauricio; Davis, Adam S.; Gonzalez-Andujar, Jose L.

    2017-01-01

    Managing production environments in ways that promote weed community diversity may enhance both crop production and the development of a more sustainable agriculture. This study analyzed data of productivity of maize (corn) and soybean in plots in the Main Cropping System Experiment (MCSE) at the W. K. Kellogg Biological Station Long-Term Ecological Research (KBS-LTER) in Michigan, USA, from 1996 to 2011. We used models derived from population ecology to explore how weed diversity, temperature, and precipitation interact with crop yields. Using three types of models that considered internal and external (climate and weeds) factors, with additive or non-linear variants, we found that changes in weed diversity were associated with changes in rates of crop yield increase over time for both maize and soybeans. The intrinsic capacity for soybean yield increase in response to the environment was greater under more diverse weed communities. Soybean production risks were greatest in the least weed diverse systems, in which each weed species lost was associated with progressively greater crop yield losses. Managing for weed community diversity, while suppressing dominant, highly competitive weeds, may be a helpful strategy for supporting long term increases in soybean productivity. In maize, there was a negative and non-additive response of yields to the interaction between weed diversity and minimum air temperatures. When cold temperatures constrained potential maize productivity through limited resources, negative interactions with weed diversity became more pronounced. We suggest that: (1) maize was less competitive in cold years allowing higher weed diversity and the dominance of some weed species; or (2) that cold years resulted in increased weed richness and prevalence of competitive weeds, thus reducing crop yields. Therefore, we propose to control dominant weed species especially in the years of low yield and extreme minimum temperatures to improve maize yields

  2. Moving integrated weed management from low level to a truly integrated and highly specific weed management system using advanced technologies

    NARCIS (Netherlands)

    Young, S.L.; Pitla, S.K.; Evert, Van F.K.; Schueller, J.K.; Pierce, F.J.; Liebman, Matt

    2017-01-01

    Integrated weed management (IWM) is one of the most commonly referred to approaches for sustainable and effective weed control in agriculture, yet it is not widely practiced, likely because current IWM systems fail to meet performance expectations of growers. The effectiveness and value of IWM syste

  3. BAOTOU CITY STUDY OF CHEMICAL CONTROL LAWN WEEDS%包头城区草坪杂草化学防除的研究

    Institute of Scientific and Technical Information of China (English)

    王立清; 李强; 刘宇

    2011-01-01

    The weed speciesis and infestation laws were studied in the garden lawn of Baotou. The results showed that; Bentazon 1 500ml/hm2 - 3 600ml/hm2 was herbicide on the stem and leaf of broad - leaved weeds in turf grass (4-15 leaves) ; Weedicide 180 - 120ml/hm2 was herbicide on the stem and leaf of annual grass weedsturf ; Weedicide II 160ml/hm2 -240ml/hm2 was a soil sealant; It was effective controlled Pennisetum flaecidum by 10% glyphosate aqueous 15kg/hm2 plus 750g washing powder. Within the recommended range of medicinal, lawn after application did not find any injury symptoms, and good safety.%本文阐述了包头城区草坪中的杂草种类,发生特点和规律,研究出适合包头城区草坪杂草的化学防除技术.结果表明:苯达松1 500ml/hm2 -3 600ml/hm2是成坪草坪中阔叶杂草(4叶-15叶)的茎叶处理剂;除杂1号80ml/hm2 - 120ml/hm2是成坪草坪中1a生禾本科杂草的茎叶处理剂;除杂2号180mL/hm2 - 240ml/hm2作为土壤封闭剂;10%草甘磷水剂15kg/hm2加750g洗衣粉助剂是多年生恶性杂草白草的防除技术.在推荐药用量范围内,施药后未发现草坪出现任何药害症状,安全性较好.

  4. Advances in Controlling Weed in Farmland in Jiangsu Province during “11 th Five Year Program” and Its Control Strategy during “12th Five Year Program”%江苏省“十一五”农田草害治理进展及“十二五”农田除草策略

    Institute of Scientific and Technical Information of China (English)

    张绍明

    2011-01-01

    Occurring characteristics of weeds in farmland and the advances in controlling during "11 th Five Year Program" are retrospected in this paper. And the article analyzes the problem such as the frequent herbicide injuries and the weed herbicide - resistance enhancing obviously which exist in current control weeds and the new situation of weed occurring in the near future ect. Under the control weeds of "12th Five Year Program" ,the author advices to promote the further and effective agricultural methods, optimize the chemical weeding technologies, improve the early - warning system and reinforce the safe medication training.%回顾了“十一五”江苏省农田杂草发生特点与防除工作进展,分析了当前农田杂草防除中存在的药害事故频发、杂草抗药性明显增强等问题,以及今后一段时期农田杂草发生新情况.提出了“十二五”农田杂草治理必须进一步推广有效的农业措施、优化化学除草技术、完善预警体系、强化安全用药培训的策略.

  5. 海南剑麻园杂草种类调查及防除技术研究%Survey of Weeds in Sisal Plantation and Control Techniques in Hainan

    Institute of Scientific and Technical Information of China (English)

    李晓霞; 沈奕德; 黄乔乔; 范志伟; 易克贤; 黄东东

    2014-01-01

    A systematical investigation of weeds was taken in sisal plantation in Hainan province , and the dominant weed groups were determined.Then, weed control experiments were conducted.The results showed that there were 121 weed species belonging to 21 families in the plantation.Among them, eight species were considered as dominant weeds , including Melinis repens, Panicum maximum, Imperata cylindrica, Digitaria setigera, Chromolaena odorata, Praxelis clematidea, Tridax procumbens and Mimosa pudica.Leguminous crops as intercrops , perennial vines as covering plants could control the weeds to some extent.Arachis hypogaea and Macroptilium atropurpureum as intercrops could have evident effect on controlling the weeds, and leguminous plants could increase the soil fertility.Therefore, their application could be further extended in this area.%本文系统调查了海南剑麻主要种植区的杂草种类,确定了剑麻园的杂草优势种群,并以此为基础进行了剑麻园除草试验。结果表明,本区剑麻园杂草发生种类共有21科121种,其中优势种杂草主要为红毛草、大黍、白茅、短颖马唐、飞机草、假臭草、羽芒菊和含羞草8种杂草;采用间种豆科植物或多年生藤本植物覆盖控草可在一定程度上控制杂草的发生,其中间种花生、大翼豆处理具有明显的防除效果,且间种豆科植物能提高土壤肥力,可以在该地区进一步推广应用。

  6. Weeds and Wildlife: Perceptions and Practices of Weed Managers

    Directory of Open Access Journals (Sweden)

    Emma H Carlos

    2014-01-01

    Full Text Available Negative impacts of invasive plants or weeds on biodiversity have been well established yet their role in providing key habitats and resources for wildlife has been little understood. Weed removal thus has the potential to adversely affect wildlife but whether this is considered during weed management is poorly known. To determine the extent of this knowledge, we examined the perceptions of weed managers regarding wildlife and weed management in Victoria, Australia. We surveyed 81 weed managers of varying levels of experience from different types of organisations, including state and local government, community groups and private companies. We found 90% of managers had observed wildlife-weed interactions and that most (70% adjusted management programmes to accommodate wildlife. Despite this, few (19% had adopted the recommended practice of combining gradual weed removal with re-vegetation. While management programmes included monitoring of native vegetation, consideration of wildlife monitoring in weed management was rare. This highlights the need for management to better understand and respond to wildlife-weed relationships. If the improvement of wildlife habitat is included in the objectives of weed programmes, as it should be, then wildlife should also be incorporated in project monitoring. This would lead to a greater understanding of the role weeds and their management have in each situation and, ultimately, more informed decision making.

  7. Transdisciplinary weed research: new leverage on challenging weed problems?

    NARCIS (Netherlands)

    Jordan, N.; Schut, M.; Graham, S.; Barney, J.N.; Childs, D.Z.; Christensen, S.B.; Cousens, R.D.; Davis, A.S.; Eizenberg, H.; Ervin, D.E.; Fernandez-Quintanilla, C.; Harrison, L.J.; Harsch, M.A.; Heijting, S.; Liebman, M.; Loddo, D.; Mirsky, S.B.; Riemens, M.; Neve, P.; Peltzer, D.A.; Renton, M.; Williams, M.; Recasens, J.; Sønderskov, M.

    2016-01-01

    Transdisciplinary weed research (TWR) is a promising path to more effective management of challenging weed problems. We define TWR as an integrated process of inquiry and action that addresses complex weed problems in the context of broader efforts to improve economic, environmental and social

  8. Transdisciplinary weed research: new leverage on challenging weed problems?

    Science.gov (United States)

    Transdisciplinary Weed Research (TWR) is a promising path to more effective management of challenging weed problems. We define TWR as an integrated process of inquiry and action that addresses complex weed problems in the context of broader efforts to improve economic, environmental and social aspec...

  9. EFICIÊNCIA DO HERBICIDA OXADIARGYL NO CONTROLE DE PLANTAS DANINHAS NA CULTURA DO ARROZ (Oryza sativa L. IRRIGADO WEED CONTROL EFFICIENCY OF THE HERBICIDE OXADIARGYL IN IRRIGATED RICE (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Geraldo José Aparecido Dario

    1999-01-01

    Full Text Available Visando avaliar a eficiência agronômica do herbicida oxadiargyl no controle de plantas daninhas ocorrentes na cultura do arroz (Oryza sativa L. irrigado, semeado em solo drenado, instalou-se ensaio em condição de campo no município de Mococa, SP, em novembro de 1993. O produto foi aplicado em pré-emergência da cultura e das plantas daninhas, nas doses de 320, 400, 480 e 560 g/ha e como padrão utilizou-se duas formulações de oxadiazon, ambas em doses de 1.000 g./ha. Os resultados obtidos permitem concluir: o herbicida oxadiargyl é eficiente no controle da tiririca-do-brejo (Cyperus iria nas quatro doses testadas e do capim-arroz (Echinochloa colonum e capim-macho (Ischaemum rugosum nas três maiores doses; o herbicida oxadiargyl causa leve fitointoxicação à cultura quando aplicado nas duas maiores doses, com os sintomas desaparecendo aos 60 dias após a aplicação; em função do controle das plantas daninhas, o herbicida oxadiargyl aumenta significativamente a produção de grãos de arroz em relação à testemunha não-capinada.In order to evaluate the agronomical efficiency of the herbicide oxadiargyl on weed control in irrigated rice (Oryza sativa L., sowm in a drained field, an experiment was established in Mococa, SP, Brazil, in November 1993. The product was applied in pre-emergence conditions of the crop and weeds, at rates of 320, 400, 480 and 560g/ha, plus a control product (oxadiazon, used in two formulations at rates of 1,000g/ha. The results allowed to conclude that: oxadiargyl is highly efficient against Cyperus iria at all rates tested; and against Echinochloa colonum and Ischaemum rugosum at rates of 400, 480 and 560g/ha. Oxadiargyl caused light phytotoxicity to the rice plants, when applied at rates of 480 and 560g/ha, but the symptoms disappeared 60 days after application. Due to weed control, oxadiargyl caused an increase in rice yield as compared to the non-weeded control.

  10. Grass and weed killer poisoning

    Science.gov (United States)

    ... medlineplus.gov/ency/article/002838.htm Grass and weed killer poisoning To use the sharing features on this page, please enable JavaScript. Many weed killers contain dangerous chemicals that are harmful if ...

  11. Disponibilidad de agua, nitrógeno y azufre en barbechos con y sin control de malezas en distintos niveles de residuos Water, nitrogen and sulphur availability in fallows with and without weed control and different residue levels

    Directory of Open Access Journals (Sweden)

    Romina Fernández

    2009-06-01

    presence, ten experiments with different levels of residue (A: 10,000 kg MS ha-1, M: 5,000 kg MS ha-1, B: less than 2,000 kg MS ha-1 were set up in Haplustolls of the tosca and dune plains in La Pampa and south of Córdoba. Each residue treatment was divided into sub-plots with different weed management: without weed control (malezas and with control (barbecho. Soil texture, bulk density, permanent wilting pint, and organic matter were determined in each site. At the beginning and end of fallow soil water contents, nitrate (N and soluble and adsorbed sulphates (S were measured in samples from 0 -0.2m depth. At all sites the water content at the beginning of fallow was high (between 51 and 100% available water. Despite this, our results showed a positive effect of residue level on water contents at the end of fallow, with a mean difference between A and B of 33%. In weed treatments no effect of residue was observed, and the difference between A and B was 10%. Water contents were more strongly affected by the presence of weeds than by residue level. Available N and S contents showed no effect of residue level, but were strongly affected by weed presence. In weed treatments sunflower seeding would be severely limited by lower available water contents, and the expectable yields would be diminished by 200 kg ha-1 or 600 kg ha-1 due to the lower availability of N and S respectively.

  12. Misturas de herbicidas para o controle de plantas daninhas do gênero Commelina Herbicide mixtures to control weeds of the genus Commelina

    Directory of Open Access Journals (Sweden)

    C.P. Ronchi

    2002-08-01

    metsulfuron methyl (4 g ha-1; oxyfluorfen combined to sulfentrazone (480 + 375 g ha-1; sequential 21 day-spaced applications of (paraquat + diuron / (carfentrazone-ethyl + glyphosate (200+400 /(30+720 and (paraquat + diuron / (paraquat + diuron (200+400 / (200+400; and no herbicide application as check control. The percentage of weed control and shoot fresh weight were evaluated. The best treatments to control both species were the sequential applications of (paraquat + diuron / (carfentrazone-ethyl + glyphosate and of (paraquat + diuron / (paraquat + diuron, followed by 2.4-D + glyphosate and carfentrazone-ethyl + glyphosate or glyphosate-potassium salt mixtures.

  13. Weed management in tropical turfgrass areas: A review

    Directory of Open Access Journals (Sweden)

    Uddin Kamal M.D.

    2012-01-01

    Full Text Available Cultural practices promoting vigorous, environmentally friendly dense turf are discussed. These are the most important and least recognized means of preventing weed establishment and encroachment which includes appropriate propagation material selection, sanitation and cultivation, adjustment of planting time, manual weed control (hand pulling, hoeing and rouging, turfgrass selection to better compete with weed populations, applying physiological stresses, fertilizer management, moisture management, mowing, and irrigation with salt water. Cultural management of weed is important because it reduces dependence on synthetic pesticides. A healthy turfgrass stand has been reported to be the best defense against weed colonization, and can be accomplished by proper mowing, watering, and fertilization. Mowing height is the clearest and best-documented cultural factor and a lower mowing height is always associated with more weeds in the turfgrass. Split application of fertilizer at intervals throughout the growing period is recommended for warm season turfgrasses. The application of fertilizer during dormant periods or periods of low growth may encourage weed growth. Hand pulling and hoeing effectively control annual and biennial seedling weeds for small areas. Irrigation by saltwater has been one method used recently to effectively control grassy broadleaved and sedge weeds in salt-tolerant turfgrass species. Cultural weed management practices in turf might provide a first defense: however, relying only on cultural control measures may not be a good idea. An integrated approach of combining cultural practices and chemicals can complement each other and give flexibility to decision making. Research is needed on optimizing the choices of herbicide and/or cultural practices as part of an integrated management system for turfgrass.

  14. Uso do novo sistema Clearfield® na cultura do girassol para o controle de plantas daninhas dicotiledóneas Use of the new Clearfield® system in sunflower culture to control dicotyledonous weeds

    Directory of Open Access Journals (Sweden)

    G. Santos

    2012-06-01

    Full Text Available A ocorrência de plantas daninhas dicotiledóneas tem limitado o aumento da área de cultivo de girassol no Brasil, devido ao seu impacto sobre a produtividade. Isso se deve à escassez de produtos registrados para a cultura com amplo espectro de ação. Em razão disso, desenvolveram-se dois experimentos com o objetivo de avaliar a eficácia e seletividade de herbicidas do grupo das imidazolinonas aplicados em pós-emergência de plantas daninhas dicotiledôneas na cultura do girassol Clearfield®. Os experimentos foram instalados no campo, em Iguatemi, distrito de Maringá-PR. Os tratamentos constituíram-se de duas testemunhas sem aplicação de herbicida, sendo uma sem capina e outra capinada, sulfentrazone (200,00 g ha-1 aplicado em pré-emergência e imazapic+imazapyr aplicados em pós-emergência nas doses de [36,75+12,25], [52,5+17,5], [12,25+36,75] e [17,5+52,5] g ha-1. Foram feitas avaliações de controle para Euphorbia heterophylla, Conyza bonariensis, Raphanus raphanistrum, Bidens pilosa, Ipomoea grandifolia e Portulaca oleracea. Também foram realizadas avaliações de intoxicação do girassol Clearfield®, estande e produtividade em kg ha-1. De acordo com os resultados, verificou-se que o uso do sistema Clearfield® mostrou-se uma ótima opção para áreas com infestação de plantas daninhas dicotiledôneas, pois possibilita a aplicação de herbicidas inibidores da enzima acetolactato sintase (ALS; os controles obtidos variaram de medianos a excelentes, além de ele não provocar injúrias à cultura e manter o estande inicial e a produtividade.The occurrence of dicotyledonous weeds has limited the increase of the area of sunflower cultivation in Brazil, due to their impact on crop yield. This is a result of a shortage of products registered for the crop with broad-spectrum control. Thus, two experiments were installed to evaluate the efficacy and selectivity of the imidazolinone herbicides applied on post

  15. Intercropping leeks to suppress weeds

    NARCIS (Netherlands)

    Baumann, D.T.; Kropff, M.J.; Bastiaans, L.

    2000-01-01

    Many field vegetables such as leek are weak competitors against weeds, causing high costs for weed management practice. Using celery as a companion cash crop was suggested to improve the weed suppression of leek. Three field experiments were carried out to study the intra- and interspecific competit

  16. Weed Biomass and Weed Species Diversity of Juvenile Citrus Trees Intercrop with some Arable Crops

    Directory of Open Access Journals (Sweden)

    Patience Mojibade OLORUNMAIYE

    2012-02-01

    Full Text Available A preliminary study was carried out to evaluate the performances of eight crops in the intercrop of citrus with arable crops at the National Horticultural Research Institute (NIHORT Ibadan, Nigeria. Eight arable crops: maize, cucumber, sweet potato, Corchorus olitorius, large green, grain amaranth, Mucuna pruriens var. utilis, and groundnut were intercropped with young citrus trees in the early planting season of 2010 with sole citrus as control. The experiment was laid out in a completely randomized block design with three replicates. Data were collected on weed flora, weed density and weed dry weight. Results showed that the relative frequencies of weeds in all the plots were less than 4% at both 6 and 9WAP. Gomphrena celosoides, Oldenlandia corymbosa and Tridax procumbens were most preponderant in appearing in all the plots. Tridax procumbens had a consistent relative frequency (2.34% in all the plots except in citrus/maize plot (0.78% at 9 WAP. Significantly lower broadleaf weed densities were obtained in citrus/sweet potato, citrus/large green, control plot and citrus/cucumber (28.67, 45.00, 50.00 and 76.33 m-2 respectively than in citrus/groundnut plot (143.00 m-2. Similarly, significantly lower grass weed densities were produced in citrus/Mucuna and citrus/sweet potato (0.33 m-2 each plots than the control plot (11.33 m-2. Whereas citrus/corchorus plot produced significantly lower broadleaf weed dry weight (37.59 g m-2 than citrus/Mucuna plot (126.47 g m-2 at 3WAP, citrus/large green plot (16.15 g m-2 and citrus/groundnut plot (123.25 g m-2 followed the same trend at 6 WAP. Sedges dry weights were less than 7 g m-2 in all the plots compared with control plot.

  17. Weed Biomass and Weed Species Diversity of Juvenile Citrus Trees Intercrop with some Arable Crops

    Directory of Open Access Journals (Sweden)

    Patience Mojibade OLORUNMAIYE

    2012-02-01

    Full Text Available A preliminary study was carried out to evaluate the performances of eight crops in the intercrop of citrus with arable crops at the National Horticultural Research Institute (NIHORT Ibadan, Nigeria. Eight arable crops: maize, cucumber, sweet potato, Corchorus olitorius, large green, grain amaranth, Mucuna pruriens var. utilis, and groundnut were intercropped with young citrus trees in the early planting season of 2010 with sole citrus as control. The experiment was laid out in a completely randomized block design with three replicates. Data were collected on weed flora, weed density and weed dry weight. Results showed that the relative frequencies of weeds in all the plots were less than 4% at both 6 and 9WAP. Gomphrena celosoides, Oldenlandia corymbosa and Tridax procumbens were most preponderant in appearing in all the plots. Tridax procumbens had a consistent relative frequency (2.34% in all the plots except in citrus/maize plot (0.78% at 9 WAP. Significantly lower broadleaf weed densities were obtained in citrus/sweet potato, citrus/large green, control plot and citrus/cucumber (28.67, 45.00, 50.00 and 76.33 m-2 respectively than in citrus/groundnut plot (143.00 m-2. Similarly, significantly lower grass weed densities were produced in citrus/Mucuna and citrus/sweet potato (0.33 m-2 each plots than the control plot (11.33 m-2. Whereas citrus/corchorus plot produced significantly lower broadleaf weed dry weight (37.59 g m-2 than citrus/Mucuna plot (126.47 g m-2 at 3WAP, citrus/large green plot (16.15 g m-2 and citrus/groundnut plot (123.25 g m-2 followed the same trend at 6 WAP. Sedges dry weights were less than 7 g m-2 in all the plots compared with control plot.

  18. Biology, ecology and management of the invasive parthenium weed (Parthenium hysterophorus L.).

    Science.gov (United States)

    Adkins, Steve; Shabbir, Asad

    2014-07-01

    Parthenium weed (Parthenium hysterophorus L.) is one of the most aggressive invasive weeds, threatening natural ecosystems and agroecosystems in over 30 countries worldwide. Parthenium weed causes losses of crops and pastures, degrading the biodiversity of natural plant communities, causing human and animal health hazards and resulting in serious economic losses to people and their interests in many countries around the globe. Several of its biological and ecological attributes contribute towards its invasiveness. Various management approaches (namely cultural, mechanical, chemical and biological control) have been used to minimise losses caused by this weed, but most of these approaches are ineffective and uneconomical and/or have limitations. Although chemical control using herbicides and biological control utilising exotic insects and pathogens have been found to contribute to the management of the weed, the weed nevertheless remains a significant problem. An integrated management approach is proposed here for the effective management of parthenium weed on a sustainable basis. © 2014 Society of Chemical Industry.

  19. Spatial and Spectral Methods for Weed Detection and Localization

    Directory of Open Access Journals (Sweden)

    Truchetet Frédéric

    2002-01-01

    Full Text Available This study concerns the detection and localization of weed patches in order to improve the knowledge on weed-crop competition. A remote control aircraft provided with a camera allowed to obtain low cost and repetitive information. Different processings were involved to detect weed patches using spatial then spectral methods. First, a shift of colorimetric base allowed to separate the soil and plant pixels. Then, a specific algorithm including Gabor filter was applied to detect crop rows on the vegetation image. Weed patches were then deduced from the comparison of vegetation and crop images. Finally, the development of a multispectral acquisition device is introduced. First results for the discrimination of weeds and crops using the spectral properties are shown from laboratory tests. Application of neural networks were mostly studied.

  20. The effect of duration of solarization on controlling branched broomrape (Phelipanche ramosa L. and some weed species

    Directory of Open Access Journals (Sweden)

    Boz, Özhan

    2012-03-01

    Full Text Available In this study, the effects of two-, four- and six-week periods of solarization on Phelipanche ramosa and other weeds were determined in tomato greenhouses between 2007-2009 in Aydin Province/Turkey. In the first year, the maximum temperatures recorded in the soil in the solarized area were 54 °C at a depth of 5 cm, 47 °C at 10 cm and 41 °C at 20 cm. In the second year, the maximum temperatures in the solarized area were 44.5 °C at 5 cm, 39.7 °C at 10 cm and 34.7 °C at 20 cm. In the first season, regardless of solarization time, solarization reduced the density of Amaranthus viridis, Setaria verticillata, Urtica urens, Solanum nigrum, Portulaca oleracea, Chenopodium album and Stellaria media by 99-100 %. Solarization’s effect on P. ramosa was 100 % regardless of the duration of solarization. In the second year, 2-, 4- and 6-week solarization periods, respectively, reduced A. viridis by 67, 73 and 93 %; S. verticillata by 78, 80 and 94 %; U. urens by 99, 100 and 100 %; and S. media by 100 % for all treatments. When P. ramosa was examined, a 2-week solarization period was found to result in a 20 % decrease and a 4-week solarization period resulted in a 47 % decrease. Six weeks of solarization reduced P. ramosa by 74 %. Additionally, there was an increase in tomato yield in response to longer periods of solarization.

  1. Weed control under integrated nutrient management systems in faba bean (Vicia faba production in Egypt Controle de plantas daninhas sob sistemas de manejo integrado em feijão de fava (Vicia faba no Egito

    Directory of Open Access Journals (Sweden)

    I.M. El-Metwally

    2008-01-01

    Full Text Available Two field experiments were conducted in two successive seasons, 2005/2006 and 2006/2007, to determine whether management can improve faba bean competitiveness with weeds, thus helping to achieve its yield potential. The experiment included five treatments, composed of organic and mineral fertilizers, alone and mixed at different rates, along with a control and six weed control treatments, including oxadiargyl, prometryn, hand hoeing treatments alone or mixed with the herbicides, and a nonweeded treatment (control.The herbicide treatments were not superior to the two hand-hoeing treatments. Using compost favored growth and yield of faba bean more than of weeds. Adding fertilizer also improved most yield parameters. Application of compost alone or combined with 50 or 100% of the recommended NPK rate improved faba bean growth in terms of net assimilation rate, specific leaf area, and leaf weight ratio as components of relative growth rate. This improvement in growth resulted in increase of seed yield, yield components and protein of faba bean. Faba bean yield performance improved under interactive fertilizer effects and weed control treatments as growth improved, as a result of nutrient release from fertilizers and weed control.Dois experimentos em condições de campo foram conduzidos em duas épocas sucessivas - 2005/2006 e 2006/2007 - para determinar se o manejo pode melhorar a competitividade do feijão-fava contra plantas daninhas e contribuir para um maior potencial de produção. Os experimentos incluíram cinco tratamentos, compostos de: fertilizantes orgânicos e minerais, isoladamente ou em mistura em diferentes doses, além do tratamento controle, e seis tratamentos de controle de plantas daninhas, incluindo tratamentos usando oxadiargyl, prometryn, manualmente ou misturados com os herbicidas e um tratamento sem plantas daninhas (controle. Os tratamentos com os herbicidas não foram superiores aos dois tratamentos manuais (hand hoeing

  2. Alternathera philoxeroides (Martius) Grisebach - alligator weed

    Science.gov (United States)

    Biological control of Alternanthera philoxeroides, alligator weed, began when George Vogt, USDA, conducted several surveys by public transport in South America during the 1960s. Three agents were released in USA and two of them, the flea beetle Agasicles hygrophila and the moth Arcola malloi were re...

  3. Weed Science and Technology. MP-17.

    Science.gov (United States)

    Alley, Harold P.; Lee, Gary A.

    This document is one in a series distributed by the Agricultural Extension Service of the University of Wyoming-Laramie. It presents the principles and methods of weed control especially as it relates to the use of herbicides. The factors influencing the effectiveness of both foliar-applied and soil-applied herbicides are discussed. A listing of…

  4. Weed Science and Technology. MP-17.

    Science.gov (United States)

    Alley, Harold P.; Lee, Gary A.

    This document is one in a series distributed by the Agricultural Extension Service of the University of Wyoming-Laramie. It presents the principles and methods of weed control especially as it relates to the use of herbicides. The factors influencing the effectiveness of both foliar-applied and soil-applied herbicides are discussed. A listing of…

  5. Controle de plantas daninhas através da palha de cana-de-açúcar associada à mistura dos herbicidas trifloxysulfuron sodium + ametrina Weed control through green cane harvesting residue combined with the herbicide mixture trifloxysulfuron sodium + ametryne

    Directory of Open Access Journals (Sweden)

    R. Gravena

    2004-09-01

    Full Text Available O objetivo deste trabalho foi avaliar os efeitos da palha de cana-de-açúcar resultante da colheita sem queima e da mistura comercial dos herbicidas trifloxysulfuron sodium + ametrina, na emergência e no acúmulo de biomassa seca de nove espécies de plantas daninhas. Os tratamentos foram distribuídos em esquema fatorial 3 x 3, sendo três quantidades de palha resultantes da colheita da cana-de-açúcar sem queima (0, 10 e 15 t ha-1, e três doses da mistura formulada dos herbicidas trifloxysulfuron sodium + ametrina (0, 1,75 e 2,00 kg ha-1, aplicados em condições de pós-emergência das plantas daninhas. As densidades das plantas daninhas foram avaliadas aos 15, 60 e 90 dias após a aplicação (DAA da mistura dos herbicidas, e a biomassa seca das plantas daninhas, aos 90 DAA. A presença de palha sobre o solo suprimiu as densidades das populações de Brachiaria plantaginea, Digitaria horizontalis, Panicum maximum, Sida glaziovii e Amaranthus hybridus a níveis de infestação considerados satisfatórios de controle. A palhada também reduziu as populações de Senna obtusifolia, Ipomoea hederifolia, I. grandifolia e I. nil, porém em níveis insatisfatórios de controle. A mistura de herbicidas nas doses estudadas controlou todas as espécies de plantas daninhas avaliadas. Na presença da palha, o controle das plantas de S. obtusifolia, I. nil, I. hederifolia e I. grandifolia somente foi satisfatório quando foi aplicada a mistura de herbicidas. Para o controle de P. maximum, houve vantagem na integração dos dois métodos de controle, em relação à aplicação isolada da menor quantidade de palha estudada ou à aplicação da mistura de herbicidas.This work aimed to evaluate the effects of green cane harvesting residue and of the herbicide mixture trifloxysulfuron sodium + ametryne on the emergence and dry biomass accumulation of nine weed species. The treatments were arranged in a 3 x 3 factorial design, with three green cane

  6. Influence of Weed Competition on Potato Growth, Production and Radiation Use Efficiency

    Directory of Open Access Journals (Sweden)

    Farzad MONDANI

    2011-08-01

    Full Text Available Weed management in potato production is one of the main cost and time consuming practices. Understanding the most effective time of weed control could reduce the costs and increase potato yield. Field study was conducted in the west region of Iran during 2006 to evaluate the effect of weeds damage in potato fields. Twelve treatments used consisted of six initial weed-free periods in which plots were kept free of weeds for 0, 10, 20, 30, 40 and 50 days after crop emergence (DAE, and then weeds were allowed to grow until harvest, and six initial weed-infested periods in which, weeds were allowed to grow for 0, 10, 20, 30, 40 and 50 DAE, then the plots were kept free of weeds until harvest. Experiment was arranged as a randomized complete block design with three replications. The results showed effect of weed competition on crop dry matter started about 40 DAE and about 90 DAE reached its maximum. The weeds competition decreased dry matter accumulation, leaf area index, crop growth rate, leaf area index duration, light absorption, light extinction coefficient and radiation use efficiency (RUE of potato. Weeds reduced the potato yield 54.8 percent. The beginning and the end of the critical period of weed control in potato (CPWC was based on 5% and 10% tuber yield loss. The onset of the CPWC ranged from 486 to 572 GDD, at 5% and 10% yield loss level corresponding to 11 and 19 days after crop emergence, respectively. The end of the CPWC varied from 1372 to 1164 GDD, at 5% and 10% yield loss level corresponding to 65 and 51 days after crop emergence, respectively. RUE in the weed infestation treatment in comparison to the weed free treatment, reduced 11.8 percent.

  7. What Price Weeding?

    Science.gov (United States)

    Ettelt, Harold J.

    1985-01-01

    Describes a study conducted at Columbia-Greene Community College's library to determine whether a book's previous non-use is indicative of future non-use; whether books are progressively less likely to be used with time; the circulation costs of weeding previously unused books; and the circulation rates of old and new books. (DMM)

  8. Efeito de períodos de controle de plantas daninhas sobre o desenvolvimento inicial de plantas de eucalipto Effects of weed control periods on initial growth and development of eucalypt

    Directory of Open Access Journals (Sweden)

    R.E.B. Toledo

    2000-01-01

    Full Text Available O objetivo deste trabalho foi estudar os efeitos dos períodos de convivência e de controle de Brachiaria decumbens sobre o desenvolvimento inicial de clones de Eucalyptus grandis x Eucalyptus urophylla. Para isso, um ensaio foi conduzido, no município de Três Lagoas-MS, no período de janeiro a dezembro de 1997. Os tratamentos experimentais consistiram de diferentes épocas e períodos de convivência das plantas daninhas na cultura do eucalipto. As épocas foram divididas em dois grupos. No primeiro, a convivência se iniciava no transplante das mudas e era estendida até 28, 56, 84, 112, 140, 168, 224, 252 e 364 dias após. No segundo grupo, a convivência se iniciava aos 0, 28, 56, 84, 112, 140, 168, 224 e 252 dias após o transplante e era estendida até o final de um ano. As principais plantas daninhas que ocorreram na área experimental foram Brachiaria decumbens e Spermacocea latifola. As plantas jovens de eucalipto foram bastante suscetíveis à interferência das plantas daninhas, apresentando um período anterior à interferência inferior a 14-28 dias. Para assegurar o desenvolvimento da cultura, o período total de prevenção à interferência foi de 140 dias, e o período crítico de prevenção à interferência, de 14-28 a 140 dias após o transplante, considerando o índice de 5% de redução em diâmetro.A field trial was carried out in Três Lagoas-MS, Brazil, from January to December of 1997, to study the effects of control and coexistence period of Brachiaria decumbens on the growth of Eucalyptus grandis x Eucalyptus urophylla clones. The experimental design was a complete randomized block design, with four replications. The treatments consisted of different periods of weed-eucalypt association. The periods were divided in two groups. In the first one, the weed-eucalypt coexistence initiated during the eucalypt transplanting, continuing up to 28, 56, 112, 140, 168, 224, 252 and 364 days after it. In the second group, the

  9. Experiment of 30%Glyphosate Oil Miscible Flowable Concentrate Against Weeds Control in Citrus Garden%30%草甘膦油悬浮剂防治柑橘园杂草药效试验

    Institute of Scientific and Technical Information of China (English)

    王平

    2013-01-01

    30%草甘膦油悬浮剂防治柑橘园杂草药效试验结果表明,30%草甘膦油悬浮剂相比较于50%草甘膦可溶性粉剂,对柑橘园杂草鼠麴草、繁缕、看麦娘等有很好的防治效果。%The experiment of 30% glyphosate oil miscible flowable concentrate agarinst weed control in citrus garden showed that ,30%glyphosate oil miscible flowable concentrate had good control effect compared to 50% glyphosate soluble powder on the weeds in citrus garden , including Herba Gnaphaii Affinis,Stellaria media(Linn.) Cyrill.,Alopecurus aequalis etc.

  10. Uso contínuo de herbicidas em citrus (Citrus sinensis (L Osbeck, I - efeitos no controle de plantas daninhas Continous use of herbicides in citros (Citrus sinensis (L. Osbeck. I - effects on weed control

    Directory of Open Access Journals (Sweden)

    Ricardo Victoria Filho

    1991-01-01

    Full Text Available A presente pesquisa foi conduzida no município de Conchal - SP, Brasil, em um Latossolo Vermelho Amarelo com 1,75% de matéria orgânica, com o objetivo de verificar o efeito do uso continuo dos principais herbicidas, no controle de plantas daninhas em um pomar de laranja 'Pera' (Citrus sinensis (L. Osbeck, enxertada sobre limão cravo (Citrus limonia Osbeck. O delineamento experimental adotado foi o de blocos ao acaso, com 12 parâmetros e 4 repetições. Os tratamentos utiliza dos com as respectiva s dose s do i.a. em kg/ha foram: terbacil a 3,2; simazine a 4,0; ametryne + secbumetone a 4,5; dichlobenil a 5,0; diuron a 3,2; bromacil a 3,2; bromacil + diuron a 3,2; paraqua t a 0,6; glyphosate a 1,61 e MSMA a 1,77, além de uma testemunha que recebia uma capina anualmente e outra que era capinada sempre que a cobertura pelas plantas daninhas atingia 25% da área da parcela. O pomar foi plantado em maio/75 e a 14 aplicação foi realizada em outubro de 1977. As parcelas continham 4 plantas em uma área de 3,0 x 18,0 m (54 m2. A última foi realizada em 1986. O efeito dos tratamentos no controle das plantas daninhas foi avaliado pela contagem por espécie botânica, assim como por avaliações visuais. Todos os herbicidas utilizados apresentaram controle de aceitável a excelente, dependendo da composição específica das plantas daninhas, e aqueles cue apresentaram os melhores índices de controle das plantas daninhas, assim como efeitos residuais mais prolongados, foram bromacil + diuron, diuron, bromacil, ametryne + secbumetone e terbacil. herbicidas aplicados em pósemergência os melhores índices de controle foram obtidos com glyphosate e paraquat.The research reported in this paper was conducted at the Conchal county in Sao Paulo State, Brazil, in a Red Yellow Latosol with 1.75% of organic matter, with the objective of studyin g the effect of continuous use of selected herbicides on the weed control on a 'Pena' Citrus sinensis (L. Osbeck

  11. 10%氰氟草酯EC防除水稻直播田禾本科杂草的效果研究%Control Effect of 10% Cyhalofop-butyl on Grassy Weeds in Direct Seeding Paddy Fields

    Institute of Scientific and Technical Information of China (English)

    朱文达; 魏守辉; 张宏军; 李林; 张文君

    2011-01-01

    To provide guidance for chemical weed management in direct seeding paddy fields, two-year field trials were conducted to evaluate the control effect of 10% cyhalofop-butyl EC on grassy weeds and application safety of it. The results showed that cyhalofop-butyl had good control effects on grassy weed Echinochloa crusgalli and Leptochloa chinensis in direct seeding paddy fields, the overall control effects for grassy weeds all reached 99% when applying 80~100 g/lun2 of effective components of cyhalofop-butyl, which can reach the highest by 99%; the control effect of cyhalofop-butyl on Echinochloa crusgalli was equivalent to that of control (quinclorac); the control effect of cyhalofopbutyl on Leptochloa chinensis was significantly higher than that of control; the overall control effect of cyhalofop-butyl on grassy weeds was also significantly higher than that of control; the application of cyhalofop-butyl significantly increased the rice yield by 18.79% to 26.99%. Therefore, cyhalofop-butyl is an excellent candidate herbicide especially for controlling Leptochloa chinensis in direct seeding paddy fields.%通过2a田间试验研究了10%氰氟草酯EC对禾本科杂草的控制效果和应用安全性,为水稻直播田草害的化学防控提供依据.结果表明,氰氟草酯对水稻直播田禾本科杂草稗草和千金子具有良好的防除效果,有效成分用量80~100g/hm2对禾本科杂草的综合防效均在90%以上,最高可达99.59%.氰氟草酯对稗草的防效与对照药剂二氯喹啉酸相当,对千金子的防效显著优于二氯喹啉酸,对禾本科杂草的综合防效也显著优于二氯喹咻酸.施用氰氟草酯能显著提高水稻产量,增产幅度一般为18.79%~26.99%.氰氟草酯可作为水稻直播田防除千金子的特效药剂.

  12. Deposição de glyphosate aplicado para controle de plantas daninhas em soja transgênica Glyphosate deposition for weed control in transgenic soybean

    Directory of Open Access Journals (Sweden)

    D.L.P. Gazziero

    2006-01-01

    , corresponding to 17; 24; 31; 38 and 45 days after soybean emergence. The targets, soybean plants, wild poinsettias, and Petri dishes on the soil surface, were collected after spraying and the tracer solution was later recovered by washing and stirring in distilled water. Samples of recovered solutions were submitted to spectrophotometer analysis, and the absorption data were converted in µL cm-2 and µL per plant. The accumulated frequencies of the original deposit data were adequately adjusted to the Gompertz model, showing high precision (R² > 0.95. The results showed that the spraying solution deposition on soybean plants and wild poinsettia reduced progressively with crop development and weed infestation, suggesting that control efficiency can be obtained with early applications.

  13. 35%丁噁乳油防除夏花生田间杂草效果研究%Effects of 35% Butachlor+Oxadiazon EC on Weeds Control in Peanut Field

    Institute of Scientific and Technical Information of China (English)

    管晓志; 路兴涛; 鞠倩; 李晓; 姜晓静; 曲明静

    2015-01-01

    为明确35%丁噁乳油对夏花生田杂草的防除效果及对花生的安全性和增产效应,采用土壤封闭喷雾法进行了田间试验研究。结果表明,35%丁噁乳油850.0~1312.5 g.a.i /hm2对花生田牛筋草、马唐草、稗草、狗尾草等一年生禾本科杂草及阔叶草苋、马齿苋有较好的防除效果。药后40d,总株防效为85.34%~93.51%,鲜重防效为95.93%~97.76%;对花生安全性较好,增产率为2.53%。%A field trial was conducted to evaluate the effects of 35% Butachlor+Oxadiazon E.C. with soil closed spray application method on weeds control in summer peanut field, peanut security and yield increase.The results showed that 35% Butachlor+Oxadiazon EC had good effect on control of weeds including annual gramineous weeds, such as Eleusine indica , Digitaria sanguinalis , Echinoch-loa crusgalli , Setaria viridis etc.and broadleaf weeds, such as Grass amaranth , Portulaca oleracea , at a dosage of 3000~3750mL/hm2 in peanut field.The plant control effect was between 85.34% and 93.51%, while fresh weight control effect was 95.93%~97.76% after treatment for 40 days.It was safe to peanut growth and could increase yield by 23.06%~26.17%.

  14. Characterization of rhizobacteria associated with weed seedlings.

    Science.gov (United States)

    Kremer, R J; Begonia, M F; Stanley, L; Lanham, E T

    1990-06-01

    Rhizobacteria were isolated from seedlings of seven economically important weeds and characterized for potential phytopathogenicity, effects on seedling growth, and antibiosis to assess the possibility of developing deleterious rhizobacteria as biological control agents. The abundance and composition of rhizobacteria varied among the different weed species. For example, fluorescent pseudomonads represented from 11 to 42% of the total rhizobacterial populations from jimsonweed and lambsquarters, respectively. Other bacteria frequently isolated were nonfluorescent pseudomonads, Erwinia herbicola, Alcaligenes spp., and Flavobacterium spp. Only 18% of all isolates were potentially phytopathogenic, based on an Escherichia coli indicator bioassay. However, the proportion of isolates that inhibited growth in seedling assays ranged from 35 to 65% depending on the weed host. Antibiosis was most prevalent among isolates of fluorescent Pseudomonas spp., the activity of which was due to siderophore production in over 75% of these isolates. Overall, rhizobacterial isolates exhibited a complex array of properties that were inconsistent with accepted definitions for plant growth-promoting and deleterious rhizobacteria. It is suggested that for development of effective biological control agents for weed control, deleterious rhizobacteria must be screened directly on host seedlings and must possess several properties including high colonizing ability, specific phytotoxin production, and resistance or tolerance to antibiotics produced by other rhizosphere microorganisms, and they must either synthesize or utilize other bacterial siderophores.

  15. Métodos de controle de plantas daninhas e seus impactos na qualidade microbiana de solo sob cafeeiro Methods of weed control and their impacts on microbial quality of soil under coffee

    Directory of Open Access Journals (Sweden)

    Rogério Melloni

    2013-02-01

    empregado para o controle de plantas daninhas em cafeeiro.Minas Gerais stands out as the largest coffee-producing state of Brazil. This crop is extremely susceptible to weeds, which can be handled by manual, mechanized and/or chemical methods, which strongly affect production costs and soil quality. In this sense, the objective of this study was to evaluate the effect of different weed control methods in and between coffee rows on the soil microbiota and its processes. For this purpose, soil samples were taken in April 2010 from an Oxisol on the experimental farm of the Agricultural Research Company of Minas Gerais (EPAMIG, in São Sebastião do Paraíso, MG, at a depth of 0-10 cm in the middle of the track (interrow of coffee and 20 cm away from the stem of the coffee trees (row, to determine the following properties: total density of bacteria and fungi, phosphate solubilizers, cellulolytic and ammonifying microorganisms, non-symbiotic diazotrophic bacteria, carbon biomass and microbial activity, metabolic quotient (qCO2 and enzymatic activity by the hydrolysis of fluorescein diacetate. The coffee plants were subjected to seven methods of weed control: mowing, coffee tandem disk harrow (grid, rotary tiller, post-emergence herbicide, pre-emergence herbicide, manual weeding, and no weed control. The results showed the complexity of the effects of these different methods on soil and its processes, with lowest impacts of manual weeding and rotary hoe. Mowing, coffee tandem disk harrow, no weed control and pre-emergence herbicide caused intermediate impacts, while the application of post-emergence herbicides in-between coffee rows caused the most negative impacts on the evaluated properties. It is suggested that these impacts must be considered when evaluating and selecting the method for weed control in coffee plants.

  16. 长江中下游油菜田杂草发生规律及实用防治策略%Occurrence Regularity of Weeds and Its Control Techniques in Winter Rape Fields of the Middle and Lower Reaches of the Yangtze River

    Institute of Scientific and Technical Information of China (English)

    鲁军雄; 陈社员; 官春云; 刘忠松; 王国槐; 肖刚

    2012-01-01

    The recent development and current status of research on weeds in winter rape fields were summarized, including the weed occurrence, distribution rule, weed damage and control techniques. The farming control and chemical control in weeds were also introduced, and the development tendency and application prospect of biological control were discussed. At the same time, the comprehensive management strategy of weed control in rape fields were put forward. We should speed up the creation of novel chemical herbicide and carry out further research on biological weed control.%概述了长江中下游地区油菜田的杂草发生种类、分布规律、危害情况以及防除措施等方面的研究进展,重点介绍了农艺防除、化学防除在杂草防除上的应用,展望了生物防除的发展趋势与应用前景.提出油菜田杂草防除上宜坚持以农艺防除为基础、化学防治为主导的综合治理策略,同时应加强新型高效环保油菜田除草剂的研发.

  17. Herbicide-resistant crops: utilities and limitations for herbicide-resistant weed management.

    Science.gov (United States)

    Green, Jerry M; Owen, Micheal D K

    2011-06-08

    Since 1996, genetically modified herbicide-resistant (HR) crops, particularly glyphosate-resistant (GR) crops, have transformed the tactics that corn, soybean, and cotton growers use to manage weeds. The use of GR crops continues to grow, but weeds are adapting to the common practice of using only glyphosate to control weeds. Growers using only a single mode of action to manage weeds need to change to a more diverse array of herbicidal, mechanical, and cultural practices to maintain the effectiveness of glyphosate. Unfortunately, the introduction of GR crops and the high initial efficacy of glyphosate often lead to a decline in the use of other herbicide options and less investment by industry to discover new herbicide active ingredients. With some exceptions, most growers can still manage their weed problems with currently available selective and HR crop-enabled herbicides. However, current crop management systems are in jeopardy given the pace at which weed populations are evolving glyphosate resistance. New HR crop technologies will expand the utility of currently available herbicides and enable new interim solutions for growers to manage HR weeds, but will not replace the long-term need to diversify weed management tactics and discover herbicides with new modes of action. This paper reviews the strengths and weaknesses of anticipated weed management options and the best management practices that growers need to implement in HR crops to maximize the long-term benefits of current technologies and reduce weed shifts to difficult-to-control and HR weeds.

  18. 30%丁草胺·乙氧氟草醚水乳剂防除甘蔗田杂草药效试验%Effects of 30%Mixed Butachlor and Oxyfluorfen EW on Controlling Weeds in Sugarcane Fields

    Institute of Scientific and Technical Information of China (English)

    邓延岗; 易芬远; 韦茂春; 赖开平; 叶一强

    2014-01-01

    以a.i.360~900 g/hm2用量,30%丁草胺·乙氧氟草醚水乳剂芽前土壤处理防除甘蔗田间杂草。试验结果表明,药后30天、60天对一年生禾本科杂草和阔叶杂草表现出良好防效,在a.i.450~540 g/hm2剂量下,对蔗田杂草防效大于86%,且对甘蔗安全。%The aim of the present study was to determine the pre-emergence application of 30%mixed butachlor and oxyfluorfen EW at a.i. 360~900 g/hm2 on controlling weeds in sugarcane fields. The results showed good control effect on annual weeds in Gramineae and broad-leaved weeds after 30 and 60 days of spraying. The control efficacy of 30%mixed butachlor and oxyfluorfen EW at dosages of a.i. 450~540 g/hm2 were more than 86%. It was safe to sugarcane at such dosages.

  19. 冀西北油用亚麻田杂草调查及化学防控技术研究%The Weed Investigation and Chemical Control Technology Research in Oil Flax Field of the Northwestern Hebei

    Institute of Scientific and Technical Information of China (English)

    李爱荣; 刘栋; 马建富; 郭娜; 郭英杰; 康爱国; 乔海明

    2015-01-01

    The weed types、communities and dominant weed species in oil flax field of the northwest-ern Hebei in the seedling stage were studied systematically,and chemical weed control test was carried out.The results showed that the weed types of local area in the seedling period of flax classified as 43 species weed of 16 families,and the dominant families were Gramineae、Compositae、Chenopodiaceae、Po-lygonaceae and Amaranth which accounted for 55.3% of all types.The dominant weed species were 11 , such as Chenopodium album L.,agopyrum tataricum(L.)Gaerth,Setaria viridis (L)Beauv.and et,al. The weed was 2 ~12 yuan community,and 6 ~9 yuan community was more than the others among them. Three kinds of controlling broadleaf weed herbicides were selected which control effects were above 85%,and the one of them was 40% 2 methyl octanoyl deltamethrin EC;Seven kinds of controlling gramineae herbicides were selected which control effects were above 90%,and the one of them was 10.8% Haloxy-fop -r -methyl.All herbicides screened were safe for oil flax and were suitable for popularizing and ap-plying in large area.%本文系统调查了冀西北地区油用亚麻田苗期杂草种类、群落及优势杂草,并开展了化学除草防除试验。结果表明,本区域油用亚麻田苗期杂草种类有16科43种,禾本科、菊科、藜科、蓼科,苋科为优势种,占杂草种类55.3%。优势杂草主要有藜、苦荞、狗尾草、野糜子、苋、野燕麦、苣荬菜、卷茎蓼、芦苇、皮碱草和野油菜11种。杂草群落类型为2~12元群落,以6~9元群落居多。试验筛选出防除阔叶杂草除草剂40%2·甲辛酰溴乳油等3种,防效在85%左右;防除禾本科杂草的除草剂10.8%高效盖草能等7种,防效在90%以上。筛选的所有除草剂对胡麻安全,可以在油用亚麻产区大面积推广应用。

  20. 50%吡氟酰草胺水分散粒剂对春小麦田阔叶杂草的防效%Control Effect of Diflufenican 50%WG on Broad-leaved Weeds in Spring Wheat Field

    Institute of Scientific and Technical Information of China (English)

    程亮

    2015-01-01

    通过田间药效试验明确50%吡氟酰草胺水分散粒剂对春小麦田阔叶杂草的防除效果和田间推荐使用剂量,结果表明,50%吡氟酰草胺水分散粒剂对小麦田杂草密花香薷、野油菜和酸模叶蓼的防除效果稍差,施药后40 d对杂草株数总体防效为53.01%~61.75%,鲜重总体防效为54.30%~58.03%。该药剂对小麦安全,较空白对照增产6.44%~8.52%。建议该药剂于春小麦3叶期前,杂草2叶期前进行茎叶喷雾处理。%Based on the field trials,the efficacy and recommended dosage of diflufenican 50% WG are determined for controlling broad-leaf weeds in spring wheat field. The result shows that diflufenican 50% WG had not good control effect to broad-leaved weeds. The integrated plant and fresh weight control effects are 53.01%~61.75% and 54.30%~58.03% on weeds respectively after 40 days after spaying. Diflufenican 50% WG had no significant effect on spring wheat growth and the yield increasing rate of spring wheat is 6.44%~8.52%after sparing. The proper period of spraying is 2 leaves in weeds(3 leaves in wheat).

  1. Wallowa Canyonlands Weed Partnership : Completion Report November 19, 2009

    Energy Technology Data Exchange (ETDEWEB)

    Porter, Mark C.; Ketchum, Sarah

    2008-12-30

    Noxious weeds threaten fish and wildlife habitat by contributing to increased sedimentation rates, diminishing riparian structure and function, and reducing forage quality and quantity. Wallowa Resources Wallowa Canyonlands Partnership (WCP) protects the unique ecological and economic values of the Hells Canyon grasslands along lower Joseph Creek, the lower Grande Ronde and Imnaha Rivers from invasion and degradation by noxious weeds using Integrated Weed Management techniques. Objectives of this grant were to inventory and map high priority weeds, coordinate treatment of those weeds, release and monitor bio-control agents, educate the public as to the dangers of noxious weeds and how to deal with them, and restore lands to productive plant communities after treatment. With collaborative help from partners, WCP inventoried {approx} 215,000 upland acres and 52.2 miles of riparian habitat, released bio-controls at 23 sites, and educated the public through posters, weed profiles, newspaper articles, and radio advertisements. Additionally, WCP used other sources of funding to finance the treatment of 1,802 acres during the course of this grant.

  2. WeedML: a Tool for Collaborative Weed Demographic Modeling

    OpenAIRE

    Holst, Niels

    2010-01-01

    WeedML is a proposed standard to formulate models of weed demography, or maybe even complex models in general, that are both transparent and straightforward to re-use as building blocks for new models. The paper describes the design and thoughts behind WeedML which relies on XML and object-oriented systems development. Proof-of-concept software is provided as open-source C++ code and executables that can be downloaded freely.

  3. Eficácia de herbicidas no controle de plantas daninhas e seletividade em leguminosas de cobertura e cupuaçuzeiro Efficacy of herbicides in weed control and selectivity in cover leguminous and cupuassu

    Directory of Open Access Journals (Sweden)

    J.F. Silva

    2003-04-01

    Full Text Available O cupuaçuzeiro Theobroma grandiflorum é uma fruteira típica da Amazônia. O seu fruto, o cupuaçu, é um dos mais populares da região e apresenta crescente aumento de demanda devido às suas características organolépticas e diversidade de uso na agroindústria. O seu cultivo, no entanto, ainda é rústico e a produção é muito afetada pela interferência das plantas daninhas. O objetivo deste trabalho foi avaliar a eficácia dos herbicidas alachlor e haloxyfop no controle das plantas daninhas e a seletividade para as leguminosas Mucuna cochinchinensis e Pueraria phaseoloides e para plantas jovens de cupuaçu. O experimento foi instalado no campo, para avaliar o efeito dos herbicidas sobre a produção de matéria seca da parte aérea e o índice de área foliar (IAF das plantas daninhas e das leguminosas e a toxicidade às plantas de cupuaçu. O alachlor, na dose de 4,0 kg ha-1, reduziu 75,60% da produção de matéria seca e 64,02% do IAF das plantas daninhas, enquanto o haloxyfop, na dose de 0,24 kg ha-1, inibiu 62,51% do acúmulo de matéria seca e 64,23% do IAF. As leguminosas M. cochinchinensis e P. phaseoloides foram tolerantes aos herbicidas. O haloxyfop, na dose de 0,12 kg ha-1, estimulou a produção de matéria seca da parte aérea e o IAF em 180,15% e 146,68%, respectivamente. Os herbicidas não causaram injúrias às plantas de cupuaçu e às leguminosas e apresentaram controle das plantas daninhas acima de 60%.The Cupuassu tree Theobroma grandflorum is a typical Amazonian plant. Its fruit, the cupuassu, is one of the most popular fruits in the region with an increasing demand due to its organoleptic characteristics and multi use by the agro industry. Its cultivation, however, is still very rudimentar and its production is highly affected by weeds. The objective of this study is to evaluate the effects of the herbicides alachlor and haloxyfop on weed control and selectivity for the leguminous plants Mucuna cochinchinensis and

  4. Determination of the critical period of weed control in corn using a thermal basis Determinação do período crítico de controle de plantas daninhas em milho utilizando uma base térmica

    Directory of Open Access Journals (Sweden)

    Francisco Bedmar

    1999-02-01

    Full Text Available Field studies were conducted over 3 years in southeast Buenos Aires, Argentina, to determine the critical period of weed control in maize (Zea mays L.. The treatments consisted of two different periods of weed interference, a critical weed-free period, and a critical time of weed removal. The Gompertz and logistic equations were fitted to relative yields representing the critical weed-free and the critical time of weed removal, respectively. Accumulated thermal units were used to describe each period of weed-free or weed removal. The critical weed-free period and the critical time of weed removal ranged from 222 to 416 and 128 to 261 accumulated thermal units respectively, to prevent yield losses of 2.5%. Weed biomass proved to be inverse to the crop yield for all the years studied. When weeds competed with the crop from emergence, a large increase in weed biomass was achieved 10 days after crop emergence. However, few weed seedlings emerged and prospered after the 5-6 leaf maize stage (10-20 days after emergence.Conduziram-se estudos no campo durante três anos no sudeste da Província de Buenos Aires, Argentina, para determinar o período crítico de controle de plantas daninhas no milho. Os tratamentos consistiram de dois períodos diferentes de interferência das plantas daninhas: um período crítico livre de plantas daninhas, e um período crítico de remoção de plantas daninhas. O período crítico livre de plantas daninhas foi ajustado por meio da equação Gompertz, enquanto o período crítico de remoção de plantas daninhas foi ajustado mediante a equação logística. Foram utilizadas as unidades térmicas para descrever cada período de interferência de plantas daninhas. O período crítico livre e o período crítico de remoção de plantas daninhas variaram de 222 a 416 e de 128 a 261 unidades térmicas acumuladas, respectivamente, para impedir uma perda de rendimento de 2,5%. A biomassa das plantas daninhas variou ao contr

  5. ArylexTM active – new herbicide active and base for new cereals herbicides: ZyparTM and Pixxaro™ EC to control wide range of broadleaf weeds in cereals in Europe

    Directory of Open Access Journals (Sweden)

    Dzikowski, Marcin

    2016-02-01

    Full Text Available Arylex™ active is a new auxinic herbicide for postemergence control of a range of important broadleaf weeds in cereals. It has been discovered and developed by Dow AgroSciences globally as a first member of the new ‘arylpicolinate‘ structural class. Arylex applied together with safener brings excellent crop safety and due to the rapid degradation in soil and plant tissue it does not limit the following crop choice. In Europe the first two herbicides containing this active are Zypar™ and Pixxaro™ EC. Zypar is a premix of Arylex and florasulam, delivering at the 1 L/ha maximum use rate 6 g ae/ha of Arylex and 5 g/ha of florasulam. It can be applied to all cereals, apart from oats, in autumn and spring. Spring application is allowed from BBCH 13 till BBCH 45, however the best performance is reached up to BBCH 32. Zypar’s spectrum of controlled weeds is very wide. Pixxaro EC is a combination of Arylex and fluroxypyr and at 0.5 l/ha dose rate delivers 6 g ae/ha of Arylex and 140 g ae/ha of fluroxypyr. It can be applied in all cereals, apart from oats, in spring from BBCH 13 till BBCH 45, while the best performance is observed between BBCH 30 and 45. Pixxaro EC shows excellent efficacy against key weeds, especially Galium aparine and at all growth stages. This herbicide brings a novel non-ALS solution and will be a key component of anti-resistance strategies for broadleaf weeds in cereals.

  6. Avaliação de herbicidas no controle de plantas daninhas na cultura da soja Evaluation of herbicides in the control of weeds in the soybean crop

    Directory of Open Access Journals (Sweden)

    A.C. De Barros

    1992-01-01

    Full Text Available Foi conduzido em Serranópolis, GO, um ensaio objetivando avaliar a eficiência e a seletividade de herbicidas no controle de plantas daninhas na cultura da soja (Glycine max (L. Merril, utilizando-se os seguintes tratamentos: A 100 g/ha de imazethapyr (ácido 2-[4,5-dihidro-4-metil-4(1-metiletil-5-oxo-1H-imidazol-2-ilo]-5-etil-3-piridinacarboxilico + surfactante, a 0,25% v/v; B tratamento A e 15 dias após, 230 g/ha de sethoxydim (2-1-etoximino-butil-5-2(etiltio-propil-3-hidroxi-2-ciclohexeno-1-ona + óleo mineral, a 0,25% v/v; C 230 g/ha de sethoxydim + óleo mineral, a 0,25% v/v; D 480 + 200 + 230 g/ha de bentazon (3-isopropil-2,1,3-benzotiadiazinona-(4-2,2-dióxido + fomesafen (5-2-cloro-4-(trifluorometil-fenoxiN-metilsulfonil-2-nitrobenzamida + sethoxydim + óleo mineral, 0,25% v/v; E 150 g/ha de imazaquim (2-[4,5-dihidro-4-metil-4-(1-metiletil-5-oxo-1H-imidazol-2-ilo]-3-quinolinacarboxílico pré-e e 230 g/ha de sethoxydim + óleo mineral, 0,25% v/v; F 250 g/ha de fomesafen + 187 g/ha de fluazipop-p-butil (butil-(R-2-(4-(5-trifluorometil-2-piridiloxi-fenoxi-propionato + surfactante a 0,2% v/v; G 120 g/ha de imazethapyr + surfactante a 0,2% v/v; H testemunha capinada; I testemunha não capinada. O delineamento experimental foi de blocos ao acaso, com quatro repetições. O capim-custódio (Pennisetum setosum (Swartz L. Rich foi eficientemente controlado por todos os tratamentos químicos, enquanto a falsa-serralha (Emilia sonchifolia DC. foi somente pelo tratamento D. O capim-carrapicho (Cenchrus echinatus L. por C, D, E e F. O joá-de-capote (Nicandra physaloides (L. Pers. por D.F. e G. Ocorreram injúrias iniciais às plantas de soja, nos tratamentos D, E. e F. As alturas de plantas e de inserção da primeira vagem, além do rendimento de grãos, não foram influenciados significativamente pelos herbicidas.An experiment was carried out in Serranópolis, State of Goiás, Brazil, aiming to evaluate herbicides efficiency in weeds control

  7. Densidades de plantas daninhas e épocas de controle sobre os componentes de produção da soja Effect of weed densities and control periods on soybean yield components

    Directory of Open Access Journals (Sweden)

    A.F. Silva

    2008-03-01

    Full Text Available Este trabalho foi conduzido com o objetivo de determinar os efeitos de diferentes densidades de plantas daninhas sobre os componentes de rendimento da soja, cv. BRS 243-RR. O delineamento experimental foi em blocos ao acaso, sendo os tratamentos constituídos pela combinação entre dez períodos crescentes de convivência das plantas daninhas com a cultura (0, 0-5, 0-10, 0-15, 0-21, 0-28, 0-35, 0-42, 0-49 e 0-125 dias e três níveis de infestação (baixa, média e alta. Na área de baixa infestação, a comunidade infestante foi composta principalmente por Brachiaria plantaginea, Ipomoea nil, Euphorbia heterophylla e outras. Nas áreas de média e alta infestação destacaram-se Brachiaria plantaginea, Ipomoea nil, Digitaria horizontalis, Cyperus rotundus e outras. B. plantaginea foi responsável pelo maior acúmulo de fitomassa seca em todos os níveis de infestação. Com relação aos componentes de produção, o número de vagens por planta foi o mais afetado pela competição, com reduções de até 58% na área de baixa infestação, 71% na de média infestação e 78% na de alta infestação. O número de sementes por vagens e peso de mil grãos se mostraram menos responsivos aos efeitos de competição; contudo, houve redução desses parâmetros, indicando relação entre o período de convivência e nível de infestação e os componentes de produção da soja.This work aimed to evaluate the effects of different weed densities on the yield components of soybean grain, cv. BRS 243 RR. The experimental design was arranged in completely randomized blocks, and the treatments consisted of increasing periods of control and three weed densities (low, medium and high. The initial periods of control were: 0, 0-5, 0-10, 0-15, 0-21, 0-28, 0-35, 0-42, 0-49 and 0-125 (harvesting. In low infestation areas, the weed community was composed mainly of Brachiaria plantaginea, Ipomoea nil, Euphorbia heterophylla and others. In medium and high

  8. Weed seed germination in winter cereals under contrasting tillage systems

    DEFF Research Database (Denmark)

    Scherner, Ananda

    2015-01-01

    to accumulate in the top soil layer and timing of herbicide applications sometimes seems to target the emergence pattern of these weeds poorly. In contrast to the management of most diseases and pests, weed management should be considered in a time frame. The abilities to produce above and below ground...... improving the targeting of direct control tactics, whatever they are chemical and non-chemical. This should ensure non-excessive use of herbicides and thus follow the principles of IPM. More specifically, focus should be on the soil layers from which the weed seeds predominantly emerge, their rate...

  9. Weed Identification Using An Automated Active Shape Matching (AASM) Technique

    DEFF Research Database (Denmark)

    Swain, K C; Nørremark, Michael; Jørgensen, R N

    2011-01-01

    Weed identification and control is a challenge for intercultural operations in agriculture. As an alternative to chemical pest control, a smart weed identification technique followed by mechanical weed control system could be developed. The proposed smart identification technique works...... on the concept of ‘active shape modelling’ to identify weed and crop plants based on their morphology. The automated active shape matching system (AASM) technique consisted of, i) a Pixelink camera ii) an LTI (Lehrstuhlfuer technische informatik) image processing library, iii) a laptop pc with the Linux OS. A 2......-leaf growth stage model for Solanum nigrum L. (nightshade) is generated from 32 segmented training images in Matlab software environment. Using the AASM algorithm, the leaf model was aligned and placed at the centre of the target plant and a model deformation process carried out. The parameters used...

  10. Effects of 10 % Metamifop WP on Gramineous Weeds Control in Direct Seeding Paddy Field%(口恶)唑酰草胺WP对水稻直播田禾本科杂草的防效

    Institute of Scientific and Technical Information of China (English)

    朱文达; 何燕红; 李林

    2011-01-01

    为明确10%(口恶)唑酰草胺WP在湖北省水稻直播田的应用前景,建立水稻直播田的杂草管理体系,研究了其对水稻直播田稗草和千金子的防除效果,并研究了杂草防除对杂草养分含量变化和水稻增产效果的影响.结果表明,施用10%(口恶)唑酰草胺WP对直播稻田中杂草的防除效果显著,对稗草、千金子的综合密度防除效果和综合鲜重防除效果分别保持在91.79%~99.44%和96.42% ~99.90%,极显著优于人工除草的防除效果.施用10%(口恶)唑酰草胺WP防除田间杂草,降低了杂草对田间养分的吸收,从而显著提高了水稻的产量,增产效果显著.%The weed control effects for Echinochloa crusgalli and Leptochloa chinensis ,the influence on the change of weed nutrient content and rice yield potential were studied to evaluate the application prospect of 10% metamifop WP and establish a weed management system in direct seeding paddy field in Hubei province. The results showed that 10% metamifop WP presented superior effects for weed control compared with the manual control. Overall quantity control effect for Echinochloa crusgalli and Leptochloa chinensis was from 91. 79% to 99. 44% and the overall fresh control effect was from 96.42% to 99.90%. Application of 10% metamifop WP in direct seeding paddy field significantly reduced the weeds absorption of nutrition resulting in a significant yield enhancing.

  11. Evaluation of control effects of glyphosate potassium salt 30% as against weeds in non-crop land%30%草甘膦钾盐水剂防除非耕地杂草田间药效评价

    Institute of Scientific and Technical Information of China (English)

    高生; 阚晓君

    2011-01-01

    Glyphosate is a no selective herbicide that has many advantages such as high effect,low dosage,low toxicity,wide weed control spectrum,free application stage and so on.The widely used glyphosate formulations are mainly isopropylamine salt and ammonium salt in China.The study aimed to explore the control effect of 30% glyphosate potassium salt AS against weeds.For this reason,glyphosate potassium salt 30% AS was applied to control weeds in non-crop land.Spraying method was leaf spraying and experimental design was the randomized block arrangement.The results showed that glyphosate potassium salt 30% AS had a good weed control effects in non-crop land.After spraying the herbicide 15 d,the total of the weed control effect was over 95%.The use of active ingredients dose which recommended was 1 000~2 000 g/hm2.%草甘膦是一种灭生性除草剂,具有高效、用量少、低毒、杀草谱广、使用时期灵活等优点.目前我国广泛使用的草甘膦制剂主要以异丙胺盐和铵盐为主,为探明草甘膦钾盐水剂的除草效果,用30%草甘膦钾盐水剂进行了非耕地杂草防除试验,试验设计采用随机区组排列,施药方法为茎叶处理.试验结果表明,30%草甘膦钾盐水剂对非耕地杂草有很好的防治效果,用药后15 d,对杂草的总防效在95%以上,推荐使用剂量为1 000~2 000 g/hm2.

  12. Evaluation on Weed Control of Different Herbicide in Tobacco Fields%几种烟田除草剂对比试验药效评价

    Institute of Scientific and Technical Information of China (English)

    孙惠青; 王凤龙; 钱玉梅; 孙慧丽; 李义强

    2012-01-01

    为筛选安全高效烟田除草剂,在全国烟草农药药效试验网中的7个点进行除草剂药效评价试验敌草胺50%可湿性粉剂(利尔化学股份有限公司)、精喹·异嗯松29%乳油(山东鸿汇烟草用药有限公司)、50%敌草胺水分散粒剂(江苏快达农化股份有限公司)、二甲戊灵450克/升微囊悬浮剂(巴斯夫公司)对烟田安全,对杂草有较好的防除效果,施药后20d杂草株数、40d杂草株数和鲜重防效,与烟草上推荐使用的敌草胺50%可湿性粉剂(印度联合磷化物有限公司)效果相当。建议推荐使用。%To choose herbicide with high effect and safety, evaluated the controlling effect of four herbicides in seven trial fields. 50% Napropamide WP (li' er), 29% quizalofop-p- ethyl-clomazone EC (Honghui), 50% napropamide WDG (Kuaida) and 450g/L pendimethalin CS (BASF) had good controlling effect on tobacco weed in fields, same as control herbicide of 50% napropamide WP (Indian) recommended. The four herbicides was safety and recom- mended to used in tobacco production.

  13. Weeding with transgenes.

    Science.gov (United States)

    Duke, Stephen O

    2003-05-01

    Transgenes promise to reduce insecticide and fungicide use but relatively little has been done to significantly reduce herbicide use through genetic engineering. Recently, three strategies for transgene utilization have been developed that have the potential to change this. These are the improvement of weed-specific biocontrol agents, enhancement of crop competition or allelopathic traits, and production of cover crops that will self-destruct near the time of planting. Failsafe risk mitigation technologies are needed for most of these strategies.

  14. Effect of Establishment Methods and Weed Management Practices on Some Growth Attributes of Rice

    Institute of Scientific and Technical Information of China (English)

    Mohammad Safdar BALOCH; Inayat Ullah AWAN; Gul HASSAN; Abdul Aziz KHAKWANI

    2006-01-01

    Studies were carried out for two years to evaluate the effect of methods of sowing and weed control practices on the productivity of transplanted and direct wet-seeded rice in Dera Ismail Khan, NWFP, Pakistan. The experiment was laid out in a randomized complete block design with a split plot arrangement. The planting techniques viz. transplanting and direct seeding were maintained in main plots while weed control practices included the use of granular herbicide Sunstar 15WG (ethoxy sulfuron),Machete 60EC (butachlor), conventional hand weeding, and the weedy check (control) were assigned to the sub-plots. Data were recorded on weed parameters like weed density and dry weed biomass 60 and 90 days after sowing (DAS); agronomic parameters including plant population, number of panicles and paddy yield and physiological parameters like leaf area index and net assimilation rate 45 and 90 DAS. The planting methods and weed management significantly influenced most of the parameters studied. The data revealed that the paddy yield and its components were significantly higher in the transplanted method than that in direct-seeded method, while the weed density and biomass were lower in the transplanted plots than the direct-seeded plots.Among weed management tools, the maximum paddy yield was obtained in hand weeding, closely followed by herbicide application Machete 60EC during both cropping seasons.

  15. 生物源除草剂壬酸对非耕地杂草的防治作用%Effects of Bioherbicide Pelargonic Acid EW on Weeds Control in the Uncultivated Field

    Institute of Scientific and Technical Information of China (English)

    刘婕; 李良德; 姜春来; 钟国华

    2012-01-01

    The aim was to study the control effects of pelargonic acid. The effect of 30% pelargonic acid on annual gramineous weeds and broad leaf weeds control in the uncultivated field was studied in this paper. By dividing testing areas and drug treating,the coverage and fresh weight control effects were investigated after 3 days,5 days and 7 days treatment. The results indicated that,a variety of annual weeds could be well controlled with 30% pelargonic acid EW at the active ingredient contents of 25-40 kg/hm2 (the test concentrations of 83.4 L/hm2 to 133.3 L/hm2). After 7 days treatment,the coverage and fresh weight control effects on annual weeds reached 85%,which were not significantly different from the contrast paraquat AS at the active ingredient contents of 0.45 kg/hm2 (the test concentration of 2.25 L/hm2). However,the coverage effects of 30% pelargonic acid EW at the active ingredient contents of 40 kg/hm2 (the test concentrations of 133.3 L/hm2) on gramineous weeds and broad leaf weeds highly reached 94.87% and 92.36% respectively as well as the fresh weight control effects reached 95.28% and 92.66% respectively. Pelargonic acid's characters of efficiency,contacting and non-selectivity could meet the demand of weeds management in the uncultivated field,which is worth further researching and exploiting.%为了了解壬酸制剂对非耕地杂草的防除效果,研究了30%壬酸水乳剂(EW)对非耕地一年生禾本科、阔叶类以及其他类杂草的田间实际防治效果.通过划分小区施药后,调查药后3、5、7天的覆盖率防效及7天的鲜重防效.结果表明,供试30%壬酸EW有效成分25 ~40 kg/hm2(制剂用量83.4~133.3 L/hm2)对各类杂草均有良好的防治效果.施药后7天覆盖度防效及鲜重防效均超过85%,与对照药剂20%百草枯AS有效成分0.45 kg/hm2(使用剂量2.25 L/hm2)差异不明显.其中,30%壬酸EW有效成分40 kg/hm2(制剂用量133.3 L/hm2)对禾本科及阔叶类

  16. 氯吡·唑草酮WP对大麦田阔叶杂草的防效及安全性%Control Efficiency of Fluroxypyr- methyl · Carfentrazone- ethy WP on Broadleaf Weeds in Barley Field and Its Safety

    Institute of Scientific and Technical Information of China (English)

    顾慧玲; 周加春; 李红阳; 张俊喜; 姜勇

    2012-01-01

    In order to nail down the control efficiency of 34% Fluroxypyr - methyl Carfentrazone - elhy WP on the broadleaf weeds (cleavers, Capsclla bursa -pastoris. Euphorbia helioscopia, Veronica polita and Vinia mtiva) in barley field and its safety to barley, the relative control and safety tests were conducted from 2010 to 2011. The results showed that 34% Fluroxypyr - methyl Carfentrazone - ethy WP could be used for controlling several kinds of broadleaf weeds in barley field, barley would not suffer from the harm of weeds in the whole growth period after utilizing this herbicide once, it damaged the weeds rapidly, and the yield of barley increased obviously. The tested dosage was safe to barley and its following crop (cotton ). The suggested dosage of 34% Fluroxypyr -methyl · Carfentrazone - ethy WP was 450 g/hm2 at the 3 ~ 4 - leaf stages of barley and the 2 - leaf stage of weeds in winter, and 450 ~ 600 g/hm2 before the regreening and jointing stages of barley from the last ten - day of February to the first ten - day of March in spring.%为了明确34%氯吡·唑草酮WP对大麦田中的阔叶杂草猪殃殃、荠菜、泽漆、婆婆纳和大巢菜的防效以及对大麦的安全性,于2010 ~2011年进行了34%氯吡·唑草酮WP防除大麦田阔叶杂草的防效和安全性试验,结果表明:34%氯吡·唑草酮WP可用于防除大麦田中多种阔叶杂草,使用一次,基本可以控制大麦全生育期不受阔叶杂草危害,且杀草速度快,增产显著.在试验剂量范围内对大麦及下茬移栽棉花安全.建议用量:冬季在大麦3~4叶期、杂草2叶期450 g/hm2较为合适,春季在2月下旬至3月上旬大麦返青拔节前以450~ 600 g/hm2为宜.

  17. Floristic and phytosociology of weeds in pastures in Maranhão State, Northeast Brazil

    Directory of Open Access Journals (Sweden)

    Jaílson Penha Costa

    2016-06-01

    Full Text Available ABSTRACT Knowledge of weed floristic composition and phytosociology are key factors for improving weed management in pastures. Information on weed species that occur in pastures in Northeast Brazil, particularly in Maranhão State is very limited. It is, therefore, important, to search for information to help farmers to control weeds in livestock farming. This paper describes the weed flora diversity and community structure parameters, including density, frequency, abundance and importance value for each weed species found in five pastures of same age and management in Maranhão State, Northeast Brazil. The weed survey was carried out using a wooden frame (80 cm x 30 cm placed randomly on the soil surface 30 times in each pasture (n = 150. Weeds were pulled out, separated by species and counted. The weed flora was represented by 996 individuals, from nine families, 15 genera and 19 species. Weed density within pastures was of 44.3 plants m-2. The weed flora was dominated by species of the Cyperaceae and Poaceae families. The most important weed species based on Importance Value were Eragrostis ciliaris (IV = 32.97, Cyperus rotundus (IV = 31,95, Cyperus luzulae (IV = 27,50, Cyperus sphacelatus (IV = 27,42, Pycreus lanceolatus (IV = 27,33 Cyperus haspan (IV = 25,72 and Eleusine indica (IV = 23,49. Weed diversity, based on Shannon Diversity Index was very high (H' = 4.37 nats ind-1. Our results could lead to improved weed management in pastures in Maranhão State, Northeast Brazil.

  18. Establishment of mixed reforestation with typical Atlantic forest species as a function of minimum or intensive soil cultivation and weed control; Estabelecimento de reflorestamentos mistos com especies tipicas da mata Atlantica, em funcao do cultivo minimo ou intensivo do solo e do controle de plantas invasoras

    Energy Technology Data Exchange (ETDEWEB)

    Goncalves, Jose Leonardo de Moraes; Gandara, Flavio [Sao Paulo Univ., Piracicaba, SP (Brazil). Escola Superior de Agricultura Luiz de Queiroz. Dept. de Ciencias Florestais]. E-mail: jlmgonca@carpa.ciagri.usp.br; Goncalves, Janio Carlos; Oliveira, Donizete Barbosa de; Simionato, Jose Luiz do Amaral [Companhia Energetica de Sao Paulo (CESP), SP (Brazil); Cenci, Silvia [Sao Paulo Univ., Piracicaba, SP (Brazil). Escola Superior de Agricultura Luiz de Queiroz (ESALQ)

    1999-07-15

    The objectives of this research were: to study the effect of different methods of site cleaning and soil preparation on the reforestation growths established with typical species of the Atlantic Forest; and to evaluate the efficiency of different methods of weed control from planting time to canopy closure. The trial was installed (from Feb to May 1995) around the reservoir of Mario Lopes Leao hydroelectric plant owned by the Electric Power of Sao Paulo (CESP), municipal district of Promissao, SP. The climate of the area is tropical with dry winter (Cwa, classification of Koeppen). The soil was characterized as an Red-Dark Latosol, medium texture. Six treatments arranged in a randomized block design with four replications were tested: 1) herbicide application over total area, planting in furrows (PF), manual weeding in the planting row (MWR) and herbicide application inter rows (HAI); 2) slashing in total area (STA), planting hole (Ph), MW R and slashing inter rows: 3) STA, slash burning (SB), heavy and light harrowing (HLH), PF, MWR and HAI; 4) STA, SB, PF, MWR and HAI; 5) STA, SB, PF, HLH, MWR and HAI; and 6) SAT, SB, two heavy harrowing, PH, selective weed control in the rows and inter rows. The plantation was accomplished with a composition of nine species: pioneers - Trema micrantha, Guazuma ulmifolia and Croton urucurana; secondary - Peltophorum dubium, Gallesia integrifolia and Ormosia arborea and climax - Tabebuia avellanedae, Hymenaea courbaril and Genipa americana. The pioneer and secondary species presented the highest results to the applied treatments. In all treatments where weed control was made with herbicide (glyphosate), the occurrence of Panicum maximum, common species in the area, was very restricted. The growth rates were intensified and the under story presented more diversified composition of weed species, with predominance of broad leaves. Opposite results were observed when weed controlled was manually or mechanically. The largest

  19. Capabilities of unmanned aircraft vehicles for low altitude weed detection

    Science.gov (United States)

    Pflanz, Michael; Nordmeyer, Henning

    2014-05-01

    Sustainable crop production and food security require a consumer and environmental safe plant protection. It is recently known, that precise weed monitoring approaches could help apply pesticides corresponding to field variability. In this regard the site-specific weed management may contribute to an application of herbicides with higher ecologically aware and economical savings. First attempts of precision agriculture date back to the 1980's. Since that time, remote sensing from satellites or manned aircrafts have been investigated and used in agricultural practice, but are currently inadequate for the separation of weeds in an early growth stage from cultivated plants. In contrast, low-cost image capturing at low altitude from unmanned aircraft vehicles (UAV) provides higher spatial resolution and almost real-time processing. Particularly, rotary-wing aircrafts are suitable for precise path or stationary flight. This minimises motion blur and provides better image overlapping for stitching and mapping procedures. Through improved image analyses and the recent increase in the availability of microcontrollers and powerful batteries for UAVs, it can be expected that the spatial mapping of weeds will be enhanced in the future. A six rotors microcopter was equipped with a modified RGB camera taking images from agricultural fields. The hexacopter operates within predefined pathways at adjusted altitudes (from 5 to 10 m) by using GPS navigation. Different scenarios of optical weed detection have been carried out regarding to variable altitude, image resolution, weed and crop growth stages. Our experiences showed high capabilities for site-specific weed control. Image analyses with regard to recognition of weed patches can be used to adapt herbicide application to varying weed occurrence across a field.

  20. Weeding Library Collections: Library Weeding Methods. Fourth Edition.

    Science.gov (United States)

    Slote, Stanly J.

    Weeding is one of the best ways to make long-term improvements to library collections, but it is also a difficult and sometimes painful task. In the tradition of previous editions, this book guides librarians in the process of methodical and efficient weeding. The book shows how to identify core collections versus the weedable items. The approach…

  1. EFEITOS DE HERBICIDAS NO CONTROLE DE PLANTAS DANINHAS, CRESCIMENTO E PRODUÇÃO DE MILHO E Brachiaria brizantha EM CONSÓRCIO EFFECTS OF HERBICIDES ON INTERCROPPED MAIZE AND Brachiaria brizantha WEED CONTROL, GROWTH AND YIELD

    Directory of Open Access Journals (Sweden)

    Lino Roberto Ferreira

    2007-09-01

    Full Text Available

    Objetivou-se nesta pesquisa avaliar o controle de plantas daninhas, o crescimento e a produção de milho e de Brachiaria brizantha consorciados, em função de doses do herbicida nicosulfuron. Foram avaliadas seis doses de nicosulfuron (0 g ha-1, 2 g ha-1, 4 g ha-1, 8 g ha-1, 16 g ha-1 e 32 g ha-1 em mistura de tanque com atrazine (1.500 g ha-1. Adicionalmente foram comparadas duas testemunhas capinadas, com ambas as espécies em monocultivo. As espécies daninhas Brachiaria plantaginea, Sorghum arundinaceum e Brachiaria decumbens foram controladas com eficiência pelo nicosulfuron nas maiores doses utilizadas. As espécies perenes Cyperus rotundus e Artemisia verlotorum não foram controladas pelos herbicidas. O milho apresentou crescimento inicial superior à braquiária, ocasionando redução na taxa de produção de biomassa e de índice de área foliar (IAF da forrageira consorciada, sendo este efeito potencializado à medida que se elevou a dose do nicosulfuron. A produção de biomassa do milho foi inferior no tratamento com atrazine, em relação aos tratados com a mistura de nicosulfuron + atrazine e à testemunha capinada. Durante o período crítico de competição, a produção de biomassa da parte aérea e o IAF do milho foram superiores ao da braquiária consorciada. Estas características permitiram bom rendimento de grãos de milho independente do manejo adotado.

    PALAVRAS-CHAVE: Integração agricultura-pecuária; plantio direto; atrazine; nicosulfuron.

    This study had the objective of evaluating weed control, growth and yield of intercropped maize and Brachiaria brizantha, as function of herbicide doses of nicosulfuron. Six nicosulfuron doses (0 g ha-1, 2 g ha-1, 4 g ha-1, 8 g ha-1, 16 g

  2. A Case Study of Allelopathic Effect on Weeds in Wheat

    Directory of Open Access Journals (Sweden)

    Slaveya T. Petrova

    2015-06-01

    Full Text Available Most powerful and effective method of weed control is by chemical substances called herbicides. In recent years, they were published quite data on different side effects of herbicides on humans, animals, crops and the environment as a whole. Therefore, the increased interest for biological weed control lately is reasonable, since its improvement and expansion will contribute to limiting excessive use of herbicides, respectively their harmful effects and will support the successful implementation of complex weed control. The purpose of this study was to investigate the effect of selected plant species, containing allelopathic active substances, on germination, growth and biomass of some widespread weeds in wheat. Experiments were carried out at laboratory conditions using seeds of wheat (Triticum aestivum L., sort Sadovo 1 and most common weeds therein: Johnson grass (Sorghum halepense (L Pers, white pigweed (Chenopodium album L., twitch (Cynodon dactylon L. and curly dock (Rumex crispus L.. Allelopathic substances were extracted with distilled water from flowers of lavender (Lavandula angustifolia Mill., leaves of basil (Ocimum basilicum L., leaves of spearmint (Mentha longifolia (L Huds., and leaves of peppermint (Mentha piperita L.. Of the tested active allelopathic plants, the most negative impact on germination of all weeds seeds (including wheat, as well as on the development of plants exhibited the water extract of lavender. Lavender and basil had a stronger negative effect on white pigweed and twitch compared with both mint species. A significant inhibitory effect of spearmint even at low concentrations was recorded on the germination of all weed species tested while the wheat was slightly affected, which manifests this plant as a potential effective species in strategies for weed control management.

  3. Study on Application of Chemical Control Techniques for Worst Weeds in Landscape Plant Nurseries in Jianghuai Region%江淮地区园林苗圃地恶性杂草化学防除技术应用研究

    Institute of Scientific and Technical Information of China (English)

    王新洋; 周根土; 张均

    2015-01-01

    In this paper the integrated control techniques regarding the main weed species, herbicides and the times,concentrations, methods of their applications for chemical weeding and artificial weeding in landscape plant nurseries were introduced. Chemical and artificial weeding techniques for 6 worst weeds in pre-emergence and seedling stages were elaborated in detail including Alternanthera philoxeroides, Commelina communis, Cyperus rotundus, Artemisia Selengensis, Cirsium setosum and Imperata cylindrica,so were the chemical weeding methods for difficult-to-control weed species Digitaria sanguinalis, Acalypha australis, Amaranthus tricolor, Eclipta prostrata, Chenopodium quinoa,Convolvu arvensis,Celosia cristata, Portulaca oleracea and Abutilon theophrasti. The study could provide practical chemical weeding operation techniques for landscape plant nurseries.%本文叙述了园林苗圃地主要杂草、除草剂,化学除草施用时间、浓度、方法,以及人工除草等综合防除技术,详细叙述了芽前、苗期化学和人工除草技术及苗圃地空心莲子草、鸭跖草、香附子、芦蒿、刺儿菜、白茅6种恶性杂草,以及防除难度较大的杂草马唐、铁苋菜、苋菜、醴肠、藜、田旋花、野鸡冠花、马齿苋、茼麻等化学除草方法,为园林苗木培育提供实用的苗圃化学除草操作技术。

  4. How Local Landholder Groups Collectively Manage Weeds in South-Eastern Australia

    Science.gov (United States)

    Graham, Sonia; Rogers, Sarah

    2017-09-01

    For two decades researchers and policy makers have been arguing that community-based collective action is needed to effectively control weeds. Yet there has been little social research into the ways that collective weed control emerges at local scales. The aim of this paper is to investigate the mechanisms through which three local landholder groups in south-eastern Australia collectively manage weeds and the measures they use to evaluate success. Semi-structured interviews were conducted with members of three Landcare groups—Jerrawa Creek/Upper Lachlan, MacLaughlin River and Towamba Valley—as well as government staff external to the groups. The results reveal that for all three groups collective weed control is about supporting individual weed control efforts as well as proactively engaging landholders with the worst infestations. The groups were seen to be successful because they focused on the common challenge that weeds pose to all landholders, thereby removing the shame associated with having weeds, and because they organised community events that were as much about building and maintaining social relationships as improving weed control. Groups were positive about what they had achieved as collectives of landholders, but also saw an important role for government in providing funding, engaging with landholders who were unwilling to engage directly with the group, and controlling weeds on public lands.

  5. Herbicide Resistant Weeds: Do Economic Thresholds Still Have a Role in Weed Management?

    Science.gov (United States)

    Concern over the development of herbicide resistant weeds has prompted a closer look at the validity of using economic thresholds (ET) as a basis for making treatment decisions. In situations where herbicide resistance is suspected, growers are often advised to employ control measures to completely ...

  6. Interference of allelopathic wheat with different weeds.

    Science.gov (United States)

    Zhang, Song-Zhu; Li, Yong-Hua; Kong, Chui-Hua; Xu, Xiao-Hua

    2016-01-01

    Interference of allelopathic wheat with weeds involves a broad spectrum of species either independently or synergistically with competitive factors. This study examined the interference of allelopathic wheat with 38 weeds in relation to the production of allelochemical 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA) in wheat with and without root-root interactions. There were substantial differences in weed biomass and DIMBOA concentration in wheat-weed coexisting systems. Among 38 weeds, nine weeds were inhibited significantly by allelopathic wheat but the other 29 weeds were not. DIMBOA levels in wheat varied greatly with weed species. There was no significant relationship between DIMBOA levels and weed suppression effects. Root segregation led to great changes in weed inhibition and DIMBOA level. Compared with root contact, the inhibition of eight weeds was lowered significantly, while significantly increased inhibition occurred in 11 weeds with an increased DIMBOA concentration under root segregation. Furthermore, the production of DIMBOA in wheat was induced by the root exudates from weeds. Interference of allelopathic wheat with weeds not only is determined by the specificity of the weeds but also depends on root-root interactions. In particular, allelopathic wheat may detect certain weeds through the root exudates and respond by increasing the allelochemical, resulting in weed identity recognition. © 2015 Society of Chemical Industry.

  7. Weed Identification Field Training Demonstrations.

    Science.gov (United States)

    Murdock, Edward C.; And Others

    1986-01-01

    Reviews efforts undertaken in weed identification field training sessions for agriprofessionals in South Carolina. Data over a four year period (1980-1983) revealed that participants showed significant improvement in their ability to identify weeds. Reaffirms the value of the field demonstration technique. (ML)

  8. Weed Identification Field Training Demonstrations.

    Science.gov (United States)

    Murdock, Edward C.; And Others

    1986-01-01

    Reviews efforts undertaken in weed identification field training sessions for agriprofessionals in South Carolina. Data over a four year period (1980-1983) revealed that participants showed significant improvement in their ability to identify weeds. Reaffirms the value of the field demonstration technique. (ML)

  9. Weed management practices in natural ecosystems: a critical overview

    Directory of Open Access Journals (Sweden)

    C.F. Reinhardt

    2000-07-01

    Full Text Available Increasing public pressure against the use of pesticides and other agricultural inputs has placed increased emphasis on the development of ecologically based pest management. One distinct reaction of the Weed Science discipline has been the swing away from herbicide research to increased research on the basic biology and ecology of weeds in hopes of reduced reliance on "technological crutches" such as herbicides and other practices that are potentially harmful to the environment. Biological control is the long-standing alternative to the use of herbicides and interest in the former practice has been boosted by the realization that the use of herbicides may lead to the development of herbicide resistance in weed populations, and that herbicide residues occur in surface and groundwater. Supporters of herbicide use would point out that biological control is generally not effective in crop production systems, and is basically slow-acting. Debates between protagonists for the exclusive use of one or the other weed management practice tend to obscure the benefits that integration of different techniques are likely to have. For natural ecosystems it is proposed that integration of the more subtle practice of biological control with the use of herbicides, which relatively quickly overwhelm a biological system with mortality, is likely to be the most effective weed management tool. Different weed management practices that could be considered in natural ecosystems are discussed in terms of three key performance rating criteria, viz. activity, selec- tivity and persistence In this concise review, general discussion is focussed on the fundamentals of weed management practices, with the view to promote concept-based approaches that are critical for the development of effective weed management strate- gies.

  10. Underseeding clovers in small grains to suppress weeds in organic farming

    Science.gov (United States)

    Organic producers are seeking alternative tactics for weed control so that they can reduce their need for tillage. In this study, we examined the impact of underseeding clovers into small grains to control weeds after harvest. Also, if the clovers winterkill, then control actions would not be need...

  11. INVASIVE WEEDS IN BOGOR BOTANIC GARDENS, INDONESIA AND ITS IMPLICATION ON SURROUNDING LANDSCAPES

    Directory of Open Access Journals (Sweden)

    Edi Santosa

    2014-07-01

    Full Text Available Conservation areas with the objective for collection and exchange plant materials have been speculated as weed bank for surrounding areas. Objective of this study was to identify and characterize ruderal invasive weeds in the Bogor Botanic Gardens (BBG. Observations were conducted in all vak (collection blocks in the BBG in order to identify the weeds species, determine their invasiveness, dominance and distribution. Weeds associations with host plants were observed. Current weed control program and data of dead trees collection were analyzed in relevant to weed. Distribution of weeds outside BBG was observed by transects method following river and road directions. Results showed that there were seven invasive weeds, i.e., Cecropia adenopus (Cecropiaceae, Cissus nodosa Blume (Vitaceae, Cissus sicyoides Blume (Vitaceae, Dioscorea bulbifera L. (Dioscoreaceae, Ficus elastica Roxb. (Moraceae, Mikania micrantha H.B.K. (Asteraceae and Paraserianthes falcataria (L. Nielsen (Fabaceae. These seven weeds species invaded 41 out of 215 plant families in BBG. Six species of weeds, i.e., C. adenopus, C. nodosa Blume., C. sicyoides Blume., D. bulbifera L., M. micrantha H.B.K. and P. falcataria (L. Nielsen, were introduced as BBG collections for the first time while the F. elastica Roxb was considered as native. It is most likely that the weeds dispersal agents are the wind, birds, bats, visitors, and waters. All of these weeds existed in surrounding areas outside BBG. Given the detrimental impact of invasive weeds on the plant collection in BBG, it is necessary to develop long–term comprehensive control measures both inside and neighboring areas by involving other government authorities beyond BBG.

  12. Effect of weeding management on the performance of local maize populations

    Directory of Open Access Journals (Sweden)

    J. Peña-Asin

    2013-11-01

    Full Text Available One of the most important stress factors in maize (Zea mays L. fields is weed competition, which reduces the crop yield. Weeds chiefly interfere with maize and establish considerable competition for light, water and nutrients. To avoid these harmful effects, there are different agronomic measures and factors among which, the most relevant are the interactions between crop and weed, weed management practices and type of germplasm. This study attempts to evaluate maize germplasm for tolerance to weed competition in order to achieve competitive ability and suitability for farming. Ten genotypes of maize, classified into two groups, i.e. improved populations and traditional cultivars, were grown under four types of weed management practices (mechanical harrowing control, chemical control, combination of harrowing and chemical control and untreated control as check for three years (from 2009 to 2011 in Zaragoza (Spain. We found that the effect of weed management practices was not significantly different, whereas the genotype effect was highly significant, with genotype EZS34 (mean yield of 7.7 Mg ha-1 showing the highest yield. Other traits, such as earliness, displayed a good behaviour under weed competition. On the other hand, harrowing management proved to be the most effective method of weed control although it did not show a significant response. The best results are associated with some maize genotypes that have a specific adaptation to local conditions, according to their genetic background.

  13. Controle de dez espécies daninhas em cana-de-açúcar com o herbicida mesotrione em mistura com ametryn e metribuzin Control of ten weed species in sugarcane using mesotrione mixed with ametryn and metribuzin

    Directory of Open Access Journals (Sweden)

    F.T. Carvalho

    2010-01-01

    -emergence control is the great challenge. The objective of this work was to evaluate the efficiency of the herbicide mesotrione in mixture with ametryn and metribuzin in the post-emergence control of ten weeds sown in sugarcane, variety RB86-7515. The weeds used in the experiment were: Brachiaria decumbens, Brachiaria plantaginea, Cenchrus echinatus, Digitaria horizontalis, Panicum maximum, Amaranthus deflexus, Bidens pilosa, Euphorbia heterophylla, Ipomoea nil and Sida glaziovii, sown in between the rows after crop emergence. The herbicides were applied on the 45th day after sugarcane planting when the monocotyledon weeds reached the third tiller phase and the dicotyledon weeds completed three to four leaves. The following treatments were carried out: mesotrione (120 g ha-1; ametryn (2,000 g ha-1; metribuzin (1,920 g ha-1; mesotrione + ametryn (120 g + 2,000 g ha-1; mesotrione + metribuzin (120 g + 1,920 g ha-1 and control with and without weeds. It was concluded that the herbicides, isolated or in mixture, were selective to sugarcane. Regarding control efficiency, it was observed that the herbicide mesotrione was efficient in the control of A. deflexus; ametryn was efficient in the control of A. deflexus, B. pilosa and I. nil; metribuzin was efficient in the control of A. deflexus, B. pilosa and S. glaziovii; mesotrione + ametryn were efficient in the control of B. decumbens, B. plantaginea, D. horizontalis, P. maximum, A. deflexus, B. pilosa, I. nil and S. glaziovii, and mesotrione + metribuzin was efficient in the control of B. plantaginea, D. horizontalis, P. maximum, A. deflexus, B. pilosa and S. glaziovii. A high synergistic effect of mesotrione was verified with the tested herbicides, with the mixture with ametryn being the most prominent.

  14. 28%丁草胺·吡嘧磺隆WP防除水稻移栽田杂草效果%Effects of Wettable Powder Mixed with Butachlor and Pyrazosulfuron for Control of Weeds in Transplanted Rice Fields

    Institute of Scientific and Technical Information of China (English)

    李宏; 朱文达; 张雷雷; 邱玉兰; 张均

    2012-01-01

    通过田间试验研究28%丁草胺·吡嘧磺隆WP对水稻移栽田杂草的控制效果和对水稻产量的影响.结果表明,28%丁草胺·吡嘧磺隆WP 226.8~525.0 g(a.i)/hm2对水稻移栽田的稗草、鸭舌草、节节草、异型莎草均具有良好的防治效果,综合密度防效和综合鲜重防效优于对照药剂60%丁草胺EC和10%吡嘧磺隆WP;并能有效降低杂草对田间氮、磷、钾和水分的吸收,增产效果明显.%To provide guidance for chemical weed management in broadcasted rice fields, trials were conducted to evaluate the effects on weed control and crop yield of a fertilizer formulation mixed with 28% butachlor and pyrazosulfuron WP. The results showed that 28% butachlor and pyrazosulfuron WP 226.8~525.0 g (a.I)/hm2 had good control effects on Echinochloa crusgalli(h.) Beauv, Monochoria vaginalis(hurm.F.), Rotala indica, Cyperus dijformis L. In transplanted rice fields. The overall fresh control effects and density control effects were significantly higher than 60% butachlor EC and 10% pyrazosulfuron WP. The application of 28% butachlor + pyrazosulfuron WP significantly reduced the weeds absorption of nutrition and water, resulting in prominent yield enhancing.

  15. Curvas de dose-resposta para avaliação do controle de fluxos de emergência de plantas daninhas pelo herbicida imazapic Dose-response curves to evaluate the control of weed emergence fluxes by imazapic

    Directory of Open Access Journals (Sweden)

    S.J.P. Carvalho

    2005-09-01

    Full Text Available O objetivo deste trabalho foi avaliar o controle de dois fluxos de emergência das plantas daninhas capim-marmelada (Brachiaria plantaginea e capim-colchão (Digitaria horizontalis pelo herbicida imazapic, aplicado em condição de pré-emergência, por meio de curvas de dose-resposta. O delineamento experimental foi o de blocos ao acaso, com quatro repetições; cada parcela constou de um vaso de 3 L de capacidade, preenchido com solo argiloso, acrescido de sementes de capim-marmelada e capim-colchão. Sendo D a dose recomendada do imazapic (140 g ha-1, os tratamentos foram: 4D, 2D, D, 1/2D, 1/4D, 1/8D, 1/16D e ausência do herbicida. Foram realizadas avaliações visuais de controle aos 30 e 60 dias após a infestação (DAI e de massa seca aos 60 DAI. Após a colheita da biomassa resultante do primeiro fluxo de emergência presente nas parcelas, os vasos foram novamente semeados com as plantas daninhas e foram realizadas novas avaliações de controle aos 30 e 60 dias após reinfestação (DAR e de massa seca aos 60 DAR. A partir dos resultados obtidos, pode-se afirmar que: o imazapic inibiu o desenvolvimento de ambas as plantas daninhas, alcançando resultados superiores a 80% de controle em todas as avaliações, para a dose recomendada, nos dois fluxos de emergência; a eficácia no controle de capim-colchão foi ligeiramente superior à do controle do capim-marmelada; e o herbicida imazapic apresentou-se como uma opção interessante para manejo dessas plantas daninhas.The objective of this work was to evaluate the control of two emergence fluxes of the weeds Brachiaria plantaginea and Digitaria horizontalis by the herbicide imazapic applied under pre-emergence conditions, by analyzing the dose-response curves. The experimental design adopted was randomized blocks, with four replicates, with each plot being a 3L capacity pot, filled with clay soil plus Brachiaria plantaginea and Digitaria horizontalis seeds. Considering D as the

  16. Integration of agronomic practices with herbicides for sustainable weed management in aerobic rice.

    Science.gov (United States)

    Anwar, M P; Juraimi, A S; Mohamed, M T M; Uddin, M K; Samedani, B; Puteh, A; Man, Azmi

    2013-01-01

    Till now, herbicide seems to be a cost effective tool from an agronomic view point to control weeds. But long term efficacy and sustainability issues are the driving forces behind the reconsideration of herbicide dependent weed management strategy in rice. This demands reappearance of physical and cultural management options combined with judicious herbicide application in a more comprehensive and integrated way. Keeping those in mind, some agronomic tools along with different manual weeding and herbicides combinations were evaluated for their weed control efficacy in rice under aerobic soil conditions. Combination of competitive variety, higher seeding rate, and seed priming resulted in more competitive cropping system in favor of rice, which was reflected in lower weed pressure, higher weed control efficiency, and better yield. Most of the herbicides exhibited excellent weed control efficiency. Treatments comprising only herbicides required less cost involvement but produced higher net benefit. On the contrary, treatments comprising both herbicide and manual weeding required high cost involvement and thus produced lower net benefit. Therefore, adoption of competitive rice variety, higher seed rate, and seed priming along with spraying different early-postemergence herbicides in rotation at 10 days after seeding (DAS) followed by a manual weeding at 30 DAS may be recommended from sustainability view point.

  17. Microwave Technologies as Part of an Integrated Weed Management Strategy: A Review

    OpenAIRE

    Graham Brodie; Carmel Ryan; Carmel Lancaster

    2012-01-01

    Interest in controlling weed plants using radio frequency or microwave energy has been growing in recent years because of the growing concerns about herbicide resistance and chemical residues in the environment. This paper reviews the prospects of using microwave energy to manage weeds. Microwave energy effectively kills weed plants and their seeds; however, most studies have focused on applying the microwave energy over a sizable area, which requires about ten times the energy that is embodi...

  18. Distribution of the most common weeds from fam. Asteraceae in Srem

    OpenAIRE

    Igić Ružica S.; Konstantinović Branko; Polić Dubravka; Anačkov Goran T.

    2002-01-01

    Weeds fall into a specific ecological group of plants and man should play the key role in controlling the process of their formation and the rate of their spreading. Damage caused by weeds is significant in both the agricultural and natural ecosystems. Therefore, special care should be paid to the current rate of their spreading, ensuring that the caused environmental changes do not become irreversible. The paper summarizes the locations in which the most common weed types of the Asteraceae f...

  19. Weeding the School Library Media Collection.

    Science.gov (United States)

    School Library Media Quarterly, 1984

    1984-01-01

    This document prepared by Calgary Board of Education, Calgary, Alberta, Canada, discusses a systematic approach to strengthening the library media collection. A statement of principle, what to weed, specific guides to weeding (by Dewey Decimal classification and type of material), what not to weed, procedures, and weeding follow-up are…

  20. 7 CFR 201.50 - Weed seed.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Weed seed. 201.50 Section 201.50 Agriculture... REGULATIONS Purity Analysis in the Administration of the Act § 201.50 Weed seed. Seeds (including bulblets or tubers) of plants shall be considered weed seeds when recognized as weed seeds by the law or rules and...

  1. 7 CFR 201.15 - Weed seeds.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Weed seeds. 201.15 Section 201.15 Agriculture... REGULATIONS Labeling Agricultural Seeds § 201.15 Weed seeds. The percentage of weed seeds shall include seeds of plants considered weeds in the State into which the seed is offered for transportation or...

  2. Weeding the School Library Media Collection.

    Science.gov (United States)

    School Library Media Quarterly, 1984

    1984-01-01

    This document prepared by Calgary Board of Education, Calgary, Alberta, Canada, discusses a systematic approach to strengthening the library media collection. A statement of principle, what to weed, specific guides to weeding (by Dewey Decimal classification and type of material), what not to weed, procedures, and weeding follow-up are…

  3. Experimental weed control of Najas marina ssp. intermedia and Elodea nuttallii in lakes using biodegradable jute matting

    Directory of Open Access Journals (Sweden)

    Markus A. Hoffmann

    2013-10-01

    Full Text Available The use of jute matting in managing the invasive aquatic macrophyte species Elodea nuttallii (Planch. H. St. John and Najas marina ssp. intermedia (Wolfg. ex Gorski Casper (Najas intermedia was studied in laboratory experiments and field trials. Four German lakes with predominant population of Najas intermedia or Elodea nuttalli were chosen for the experiment and areas between 150 and 300 m² were covered with jute textile. The effect of the matting on the growth of invasive and non-invasive macrophytes was determined through comparison with control transects. Biodegradable jute matting successfully suppressed the invasive macrophyte Najas intermedia and significantly reduced the growth of Elodea nuttalli in lakes. The results indicate that the capability of the matting to inhibit the growth of Elodea nuttallii and Najas intermedia depends on the mesh size of the jute weaving and that environmental conditions can affect its efficiency. Various indigenous species like Charales or Potamogeton pusillus L. were able to grow through the jute fabric and populate the treated areas. Until the end of the vegetation period, none of the invasive species were able to penetrate the covering and establish a stable population; in fact, in the subsequent year the jute matting affected only the spread of Najas intermedia. Jute matting proved to be an easy-to-use and cheap method to control the growth of Elodea nuttallii and Najas intermedia.

  4. Effect of Monument on turf weeds control in gol f course%抹绿对高尔夫球场草坪杂草防治效果的研究

    Institute of Scientific and Technical Information of China (English)

    李佳岭; 谢新春; 张巨明; 刘天增

    2013-01-01

    华南地区高尔夫球场中牛筋草(Eleusine indica)、马唐(Digitaria sanguinalis)、水蜈蚣(Ky-llingabrevifolia)、碎米莎草(Cyperusiria)、日照飘拂草(Fimbristylismiliacea)等恶性杂草危害严重,是该地区高尔夫球场养护管理中最重要的问题之一。在该区高尔夫球场常用的老鹰草(Tifeagle Ber-mudagras)草坪和结缕草(Zoysiajaponica)草坪上分别进行独立试验,通过杂草受害盖度、中毒症状、鲜重防效、草坪景观质量、安全性等几个方面,探究发现药剂抹绿(MONUMENT)对三叶鬼针草(Bi-dens pilosa )、马唐、水蜈蚣、日照飘拂草、夏飘拂草(Fimbristylis aestwalis )、碎米莎草、畦畔莎草(C. haspan)、石胡荽(Centipedaminima)、含羞草(Mimosa pudica)有极佳防效。%Exotic weeds including Eleusine indica,Digitaria sanguinalis,Kyllinga brevifolia,Cyperus iria,Fimbristylis miliacea are seriously damaging the golf course in south China,which is one of significant problems in daily management and maintenance of golf course turf.This study was conducted to test the weed control effect of MONUMENT herbicide on turfgrasses (Cynodon dactylon cv.Tifeagle and Zoysia japonica) in golf course.The weeds coverage,symptoms,control efficiency,turf quality,and safety to turfgrasses were measured after applying the herbicide.The results indicated that MONUMENT have excellent control effect on Bidenspilosa,Digitariasanguinalis,Mimosapudica,Kyllingabrevifolia,Fimbristylismiliacea,Fimbristylis miliacea,Cyperus iria,Centipedaminima.

  5. Assessment of Corn Densities on Ecological Indices of Weed Species

    Directory of Open Access Journals (Sweden)

    G Mahmoodi

    2012-06-01

    Full Text Available Diversity, dominance, and stability of weeds are the most important ecological properties in agricultural systems, which influenced by management factors such as crop density, abundantly. This experiment was conducted in 2009 at Ferdowsi University of Mashhad Research Field. The experimental design was interval mapping with four levels of corn densities (5, 6, 7 and 9 plant.m-2 and four levels of weed control (full-control, without control, broad-leaves control and grasses control. Weed sampling was done at 3 stages included beginning and end of critical period weed control and harvesting time. The results showed that the effect of plant density on species diversity was significant; some how the amount of Shanon and Simpson Indices were lowest in the 9 plant.m-2 (0.39 and 0.45, respectively and greatest in 5 plant.m-2 (0.84. The results also showed that the maximum amount of dominance index was observed in 9 plant.m-2, that was seen in Echinochloa crus- galli and Convulvulus arvensis at the beginning of growing season, then in Solanum nigrum and Amaranthus retroflexus in the end of growing season. The amount of community dominance index in 9 plant.m-2 was higher than other densities, and it decreased with decline of densities. based on the results of present experiment the linear relationship between plant species and area was found. The calculated amount of Alpha and Beta diversities. in a θ and β scales based on coefficients of this relationship were 0.534 (four species per unit area and 0.29 (two species per unit area, respectively. In conclusion the result of this experiment pointed that the weeds diversity decreased with increasing of corn density, weed diversity decreased and therefore, having appropriate plant density is very efficient for sustainable weed management.

  6. Evaluation and Modeling of Camel Thorn (Alhagi Maurorum Weed Cutting by Water Jet

    Directory of Open Access Journals (Sweden)

    M Naghipour Zade Mahani

    2014-04-01

    Full Text Available Due to the importance of weed control and the limitations of mechanical methods in some places, in this research the water jet cutting for weed control was investigated. The cutting tests were performed on camel thorn weed in Shahid Bahonar university of Kerman. The water jet pressure of 90 bars was achieved with the aid of a suitable pump. The cutting time was studied in a completely randomized factorial design experiment (CRD with five replications. Factors of experiments are: stem diameter in 2 levels (smaller and larger than 5 mm, distance of spraying jet from weeds in 3 levels (10, 20 and 30 cm and two types of plant holders: blade and plate. The results showed that stem diameter and jet distance from the weed stem had significant effects on cutting time (at the 1%. The mean comparison of parameters showed that with increase of stem diameter the cutting time increased and any increase in jet distance from the weeds decreased the cutting time linearly with R2=0.96 and R2=0.99 for small and large diameter weeds, respectively. The minimum cutting time was measured at 30 cm of the jet from small diameter of stems. A multivariate linear regression model was also proposed for cutting weed parameters. It can be concluded that due to the flexibility of water jet cutting for restricted places, hydrodynamic control of weeds is proposed as a complementary method and sometimes a competing substitute method.

  7. Potential uses of gut weed Enteromorpha spp. as a feed for herbivorous fish.

    Science.gov (United States)

    Anh, Nguyen Thi Ngoc; Hien, Tran Thi Thanh; Hai, Tran Ngoc

    2013-01-01

    Three separate experiments were performed to assess the potential use of gut weeds Enteromorpha spp. as a food source for herbivorous fish. The fresh or dried gut weeds were used as a direct feed to replace commercial feed in an alternative approach for feeding spotted seat (Scatophagus argus), red tilapia (Oreochromis sp.), and giant gourami (Osphronemus goramy) juveniles for 60 days, 45 days, and 56 days, respectively. Four feeding regimes were applied to triplicate tanks and fish was fed daily either commercial feed or gut weed: (1) single commercial feed everyday as a control treatment, (2) single gut weed daily and 2 alternative feeding regimes where (3) 1 day commercial feed and 1 consecutive day gut weed or and (4) 2 consecutive days gut weed. The results indicated that survival of experimental fish was not affected by the feeding treatments. Growth performance of the S. argus fed single gut weed was not significantly different from the control group (P>0.05). Growth rates of Oreochromis sp. and O. goramy in the alternative feeding treatments were comparable to the control treatment. Application of the combined feeding regimes, feed conversion ratio could be reduced from 26.1 to 57.8%. These results indicated that fresh and dried gut weed can be used as a feed to substitute commercial feed for herbivorous fish. Moreover, using gut weeds as a feed could improve water quality in the rearing tanks.

  8. Taxonomic and life history bias in herbicide resistant weeds: implications for deployment of resistant crops.

    Directory of Open Access Journals (Sweden)

    Jodie S Holt

    Full Text Available Evolved herbicide resistance (EHR is an important agronomic problem and consequently a food security problem, as it jeopardizes herbicide effectiveness and increases the difficulty and cost of weed management. EHR in weeds was first reported in 1970 and the number of cases has accelerated dramatically over the last two decades. Despite 40 years of research on EHR, why some weeds evolve resistance and others do not is poorly understood. Here we ask whether weed species that have EHR are different from weeds in general. Comparing taxonomic and life history traits of weeds with EHR to a control group ("the world's worst weeds", we found weeds with EHR significantly over-represented in certain plant families and having certain life history biases. In particular, resistance is overrepresented in Amaranthaceae, Brassicaceae and Poaceae relative to all weeds, and annuality is ca. 1.5 times as frequent in weeds with EHR as in the control group. Also, for perennial EHR weeds, vegetative reproduction is only 60% as frequent as in the control group. We found the same trends for subsets of weeds with EHR to acetolactate synthase (ALS, photosystem II (PSII, and 5-enolpyruvylshikimate-3-phosphate (EPSP synthase-inhibitor herbicides and with multiple resistance. As herbicide resistant crops (transgenic or not are increasingly deployed in developing countries, the problems of EHR could increase in those countries as it has in the USA if the selecting herbicides are heavily applied and appropriate management strategies are not employed. Given our analysis, we make some predictions about additional species that might evolve resistance.

  9. Taxonomic and life history bias in herbicide resistant weeds: implications for deployment of resistant crops.

    Science.gov (United States)

    Holt, Jodie S; Welles, Shana R; Silvera, Katia; Heap, Ian M; Heredia, Sylvia M; Martinez-Berdeja, Alejandra; Palenscar, Kai T; Sweet, Lynn C; Ellstrand, Norman C

    2013-01-01

    Evolved herbicide resistance (EHR) is an important agronomic problem and consequently a food security problem, as it jeopardizes herbicide effectiveness and increases the difficulty and cost of weed management. EHR in weeds was first reported in 1970 and the number of cases has accelerated dramatically over the last two decades. Despite 40 years of research on EHR, why some weeds evolve resistance and others do not is poorly understood. Here we ask whether weed species that have EHR are different from weeds in general. Comparing taxonomic and life history traits of weeds with EHR to a control group ("the world's worst weeds"), we found weeds with EHR significantly over-represented in certain plant families and having certain life history biases. In particular, resistance is overrepresented in Amaranthaceae, Brassicaceae and Poaceae relative to all weeds, and annuality is ca. 1.5 times as frequent in weeds with EHR as in the control group. Also, for perennial EHR weeds, vegetative reproduction is only 60% as frequent as in the control group. We found the same trends for subsets of weeds with EHR to acetolactate synthase (ALS), photosystem II (PSII), and 5-enolpyruvylshikimate-3-phosphate (EPSP) synthase-inhibitor herbicides and with multiple resistance. As herbicide resistant crops (transgenic or not) are increasingly deployed in developing countries, the problems of EHR could increase in those countries as it has in the USA if the selecting herbicides are heavily applied and appropriate management strategies are not employed. Given our analysis, we make some predictions about additional species that might evolve resistance.

  10. Controle de plantas daninhas na cultura do milho-pipoca com herbicidas aplicados em pós-emergência Weed control in popcorn maize using post emergence herbicide

    Directory of Open Access Journals (Sweden)

    A. Jakelaitis

    2005-09-01

    Full Text Available Objetivou-se avaliar a eficiência de controle de plantas daninhas, a tolerância e a produção de milho-pipoca UFVM2 aos herbicidas atrazine (1.500 g ha-1, foramsulfuron + iodosulfuron methyl sodium + atrazine (15+1+1.500 e 30+2+1.500 g ha-1, foramsulfuron + iodosulfuron methyl sodium (15+1, 30+2, 45+3 e 60+4 g ha-1, nicosulfuron + atrazine (8+1.500 e 16+1.500 g ha-1 e nicosulfuron (16 g ha-1. A aplicação dos herbicidas foi realizada aos 25 dias após a emergência da cultura. As plantas daninhas predominantes na área foram Brachiaria plantaginea, Brachiaria decumbens e Ipomoea spp. Os herbicidas foramsulfuron + iodosulfuron methyl sodium, em todas as doses testadas, proporcionaram maiores índices de toxidez à cultura, aos 7, 14 e 28 dias após a aplicação dos tratamentos (DAA. Todas as combinações de herbicidas proporcionaram controle acima de 90% para B. plantaginea e B. decumbens, aos 28 DAA. O nicosulfuron aplicado isoladamente proporcionou controle de apenas 80% e o atrazine não controlou essas espécies daninhas. Para Ipomoea spp., nenhum tratamento herbicida proporcionou controle equivalente ao da testemunha capinada. A competição das plantas daninhas resultou em menores teores de clorofila total, N, P e K no tecido foliar das plantas de milho-pipoca e menor rendimento de grãos. Para o cultivar UFVM2, as sulfoniluréias isoladas ou associadas ao atrazine não afetaram o estado nutricional da cultura, o rendimento e a capacidade de expansão dos grãos de milho-pipoca.The efficiency of different herbicide combinations for weed control and tolerance and yield of UFVM2 popcorn maize were evaluated. The herbicide treatments and respective doses were: atrazine (1.500 g ha-1; foramsulfuron + iodosulfuron methyl sodium + atrazine (15+1+1.500 and 30+2+1.500 g ha-1; foramsulfuron + iodosulfuron methyl sodium (15+1, 30+2, 45+3, and 60+4 g ha-1; nicosulfuron + atrazine (8+1.500 and 16+1.500 g ha-1 and nicosulfuron (16 g ha-1. The

  11. Real-time weed detection, decision making and patch spraying in maize, sugarbeet, winter wheat and winter barley

    DEFF Research Database (Denmark)

    Gerhards, R; Christensen, Svend

    2003-01-01

    online weed detection using digital image analysis, computer-based decision making and global positioning systems (GPS)-controlled patch spraying. In a 4-year study, herbicide use with this map-based approach was reduced in winter cereals by 60% for herbicides against broad-leaved weeds and 90% for grass......Information on temporal and spatial variation in weed seedling populations within agricultural fields is very important for weed population assessment and management. Most of all, it allows a potential reduction in herbicide use, when post-emergence herbicides are only applied to field sections...... with weed infestation levels higher than the economic weed threshold; a review of such work is provided. This paper presents a system for site-specific weed control in sugarbeet (Beta vulgaris L.), maize (Zea mays L.), winter wheat (Triticum aestivum L.) and winter barley (Hordeum vulgare L.), including...

  12. Herbicide-resistant crops and weed resistance to herbicides.

    Science.gov (United States)

    Owen, Micheal D K; Zelaya, Ian A

    2005-03-01

    The adoption of genetically modified (GM) crops has increased dramatically during the last 3 years, and currently over 52 million hectares of GM crops are planted world-wide. Approximately 41 million hectares of GM crops planted are herbicide-resistant crops, which includes an estimated 33.3 million hectares of herbicide-resistant soybean. Herbicide-resistant maize, canola, cotton and soybean accounted for 77% of the GM crop hectares in 2001. However, sugarbeet, wheat, and as many as 14 other crops have transgenic herbicide-resistant cultivars that may be commercially available in the near future. There are many risks associated with the production of GM and herbicide-resistant crops, including problems with grain contamination, segregation and introgression of herbicide-resistant traits, marketplace acceptance and an increased reliance on herbicides for weed control. The latter issue is represented in the occurrence of weed population shifts, the evolution of herbicide-resistant weed populations and herbicide-resistant crops becoming volunteer weeds. Another issue is the ecological impact that simple weed management programs based on herbicide-resistant crops have on weed communities. Asiatic dayflower (Commelina cumminus L) common lambsquarters (Chenopodium album L) and wild buckwheat (Polygonum convolvulus L) are reported to be increasing in prominence in some agroecosystems due to the simple and significant selection pressure brought to bear by herbicide-resistant crops and the concomitant use of the herbicide. Finally, evolution of herbicide-resistant weed populations attributable to the herbicide-resistant crop/herbicide program has been observed. Examples of herbicide-resistant weeds include populations of horseweed (Conyza canadensis (L) Cronq) resistant to N-(phosphonomethyl)glycine (glyphosate). An important question is whether or not these problems represent significant economic issues for future agriculture. Copyright 2005 Society of Chemical Industry

  13. Tolerance and selectivity of cereal species and cultivars to postemergence weed harrowing

    DEFF Research Database (Denmark)

    Rasmussen, Jesper; Nielsen, Helle Højland; Gundersen, Hanne

    2009-01-01

    for analyzing crop tolerance on the basis of digital image analysis. Crop tolerance is defined as the ability of the crop to avoid yield loss from cultivation in the absence of weeds, and it has two components: resistance and recovery. Resistance is the ability of the crop to resist soil covering and recovery......POST weed harrowing and other cultivation methods to control weeds in early crop growth stages may result in crop damage due to low selectivity between crop and weeds. Crop tolerance to cultivation plays an important role but it has not been clearly defined and analyzed. We introduce a procedure...... abilities to suppress weeds. The order of species' tolerance to weed harrowing was triticale > wheat > barley > oat and the differences were mainly caused by different abilities to recover from soil covering. At 25% soil covering, grain yield loss in triticale was 0.5%, in wheat 2.5%, in barley 3...

  14. Real World of Industrial Chemistry: The Challenge of Herbicides for Aquatic Weeds.

    Science.gov (United States)

    Martin, Dean F.; Martin, Barbara B.

    1985-01-01

    Discusses problems in selecting the correct herbicide for use in controlling aquatic weeds, considering specificity, size of the market, fear of trace contaminants, and herbicide resistance in weeds. Also summarizes some successful herbicides, providing a table listing mode of action of some herbicides used for control of aquatic plants. (JN)

  15. Taxonomic diversity and distinctness indices in assessment of weed communities

    Directory of Open Access Journals (Sweden)

    Magdalena Jastrzębska

    2012-12-01

    Full Text Available This paper contains an analysis of taxonomic weed biodiversity in the cultivation of spring barley in the period of 1990-2004, grown in crop rotation after potato with a 25% share of this cereal (potato - spring barley - field pea - winter triticale as well as in crop rotation with its 75% share (potato - spring barley - spring barley - spring barley in which barley was grown once and twice after the same barley crop. No weed control was used in the present experiment. Every year in the spring (at full emergence of the cereal crop and before harvest, the species composition and the numbers of individual weed species were determined, as well as weed biomass before harvest. On this basis, the taxonomic diversity and distinctness indices were calculated. Potato/barley crop rotation with a 25% share of this cereal and growing spring barley once and twice after the same barley crop did not differentiate taxonomic weed biodiversity. However, it was positively correlated with rainfall abundance during the growing season and negatively correlated with mean temperature. The taxonomic diversity indices were positively correlated with species richness and species diversity, whereas the taxonomic distinctness indices did not generally show any relationship with these measures. Spring barley grain yield did not depend on taxonomic biodiversity of weed communities.

  16. Biodiversity Of Weed Communities In Organic And Conventional Orchards

    Directory of Open Access Journals (Sweden)

    Lisek Jerzy

    2015-06-01

    Full Text Available The aim of the study was to analyze the occurrence of segetal and ruderal weeds in young apple and cherry organic orchards, where weeds under tree canopies were controlled mechanically with a rototiller, and in conventional orchards, where post-emergence herbicides were used. The research material consisted of phytosociological relevés recorded according to the Braun-Blanquet method, in three organic and three conventional orchards, situated near Skierniewice (central Poland, in 2010-2013. On the basis of the collected source material, species composition for the synanthropic flora, as well as phytosociological stability, the cover factor, and weed infestation rate for the analysed species were determined. The total number of the recorded weeds and the average number of weed species in a single relevé were for each of the three organic orchards greater than for the conventional orchards. The organic orchard situated in the same location as the conventional orchard was characterized by a greater biodiversity of flora. Systematic shallow cultivation of the soil, without herbicide treatments, resulted in the proliferation of perennial weeds.

  17. 作物格局、土壤耕作和水肥管理对农田杂草发生的影响及其调控机制%Effects of crop pattern,tillage practice and water and fertilizer management on weeds and their control mechanisms

    Institute of Scientific and Technical Information of China (English)

    赵玉信; 杨惠敏

    2015-01-01

    Field weeds pose significant threats to agricultural production.Weed occurrence is affected by many factors,both natural and artificial.Crop pattern,tillage practices and the management of water and fertiliser are three fundamental factors.In this review paper,we summarize the effects of crop species and the temporal and spatial patterns of cropping.We describe the weed control outcomes of different planting modes,and com-pare changes in weed communities under different tillage practices and fertiliser applications.Possible control mechanisms are identified by considering the competition for resources between crops and weeds,crop allelopa-thy and changes in soil seed banks.Reasonable crop rotation,intercropping and mixed intercropping signifi-cantly restrain weed occurrence.No-tillage can increase weed community diversity.Straw mulch can reduce weed density and biomass.The effects of fertiliser application on weeds vary due to differences in crop species, fertiliser amount and type.Long-term balanced fertilisation can reduce weed density but increase weed commu-nity diversity.Irrigation and improved efficiency of natural precipitation use can inhibit upland weeds,and deep water management at appropriate times can effectively control some weeds in paddy fields.We conclude with some suggestions and prospects for future research on weed control.%农田杂草的危害是阻碍农业生产快速、健康发展的主要因素之一。农田杂草的发生受到诸多自然因素的影响和人工措施的调控,而作物格局、土壤耕作和水肥管理是除施用除草剂外最基本的人工干扰措施。本文综述了作物种类和时空格局对杂草的影响,阐述了主要的作物种植模式防治杂草的效果,并比较了不同土壤耕作和水肥管理措施下杂草群落的变化,重点剖析了杂草发生的调控机制,探讨了通过作物与杂草的资源竞争、作物的他感作用及土壤种子库的变化来调控杂草发生

  18. Effect of the Mixture of Glyphosate and 2,4-D on Weeds Control in Citrus Orchard%草甘膦与2,4-D混用对柑橘园杂草的防治效果

    Institute of Scientific and Technical Information of China (English)

    李良德; 姜春来; 刘婕; 钟国华

    2012-01-01

    The effect of 10.8% glyphosate? 2, 4—D (AS) on weed control in citrus orchard was reported. The results indicated that the tested formulation of 10.8% glyphosate -2, 4-D (AS) could get good control effectiveness against almost all gramineae, broad-leave and other kind of weeds when applied at the preparation dosage 15 750-31 500 mL/hm2, which was not remarkably different from the 41% glyphosate diisopropylamine salt (AS) at concentration of 4 116 mL/hm2 and obviously better than 72% 2,4-D butylate EC at concentration of 8 100 mL/hm2. This mixture was worthy recommended for weeds management with significant efficiency, long period of validity and good safety in citrus orchard.%研究了10.8%草甘膦·2,4-D水剂(AS)对柑橘园杂草的田间防治效果.结果表明,10.8%草甘膦·2,4-D AS制剂用量15 750~31 500 mL/hm2几乎对所有禾本科、阔叶类和其他类杂草均有较好的防治效果,防效与41%草甘膦异丙胺盐AS制剂用量4 116 mL/hm2相当,显著优于72% 2,4-D丁酯EC制剂用量8 100 mL/hm2的防效,作用较快,持效期较长.

  19. Weed control in young coffee plantations through post emergence herbicide application onto total area Controle de plantas daninhas em cafezais recém-implantados, com herbicidas aplicados em pós-emergência em área total

    Directory of Open Access Journals (Sweden)

    C.P. Ronchi

    2004-12-01

    Full Text Available This study was carried out to investigate the efficiency of several herbicides under field conditions, by post-emergence application onto the entire area, their effect on the control of weeds in young coffee plantations and commercial coffee and bean intercropping system, as well as on both crops. Seedlings of Coffea arabica cv. Red Catuaí with four to six leaf pairs were transplanted to the field and treated according to conventional agronomic practices. A bean and coffee intercropping system was established by sowing three lines of beans in the coffee inter-rows. At the time the herbicides were sprayed, the coffee plants had six to ten leaf pairs; the bean plants, three leaflets; and the weeds were at an early development stage. Fluazifop-p-butyl and clethodim were selective for coffee plants and controlled only Brachiaria plantaginea and Digitaria horizontalis efficiently. Broad-leaved weeds (Amaranthus retroflexus, Bidens pilosa, Coronopus didymus, Emilia sonchifolia, Galinsoga parviflora, Ipomoea grandifolia, Lepidium virginicum, and Raphanus raphanistrum were controlled with high efficiency by sole applications of fomesafen, flazasulfuron, and oxyfluorfen, except B. pilosa, C. didymus, and R. raphanistrum for oxyfluorfen. Sequential applications in seven-day intervals of fomesafen + fluazifop-p-butyl, or clethodim, and two commercial mixtures of fomesafen + fluazifop-p-butyl simultaneously controlled both types of weed. Cyperus rotundus was only controlled by flazasulfuron. Except for fluazifop-p-butyl and clethodim, all herbicide treatments caused only slight injuries on younger coffee leaves. However, further plant growth was not impaired and coffee plant height and stem diameter were therefore similar in the treatments, as evaluated four months later. Fomesafen, fluazifop-p-butyl, and clethodim, at sole or sequential application, and the commercial mixtures of fomesafen + fluazifop-p-butyl were also highly selective for bean crop; thus

  20. Eficiência do herbicida oxyfluorfen, quando veiculado ao papel, no controle de algumas espécies daninhas Effect of the herbicide oxyfluorfen using paper as a vehicle on the weed control

    Directory of Open Access Journals (Sweden)

    Alexandre J. Bezutte

    1995-01-01

    Full Text Available Com o objetivo de encontrar um método alternativo de aplicação de herbicidas, estudou-se a eficiência do oxyfluorfen aplicado em três doses (0, 480 e 960g/ha sob duas formas (pulverizado e veiculado em folha de papel no controle em pré-emergência de Bidens pilosa, Desmodium tortuosum, Eleusine indica, Sida rhombifolia Amaranthus retroflexus, Acanthospermum hispidum e Digitaria horizontalis. A pulverização do oxyfluorfen foi realizada com o auxílio de um pulverizador, e sua veiculação foi feita através da determinação prévia da capacidade de embebição do papel. Obteve-se a concentração necessária da calda quando o papel atingiu completa embebição e então, escorrido o excesso, foi posto a secar na sombra. O delineamento experimental foi o inteiramente casualizado, com cinco repetições. Foram realizadas avaliações aos 30, 45 e 60 dias após a aplicação (DAA, e os resultados indicaram que os métodos de aplicação utilizados, assim como as doses, apresentaram excelente controle de B. pilosa, D. tortuosum, E. indica S. rhombifolia, D. horizontalis e A. retroflexus até 60 DAA, reduzindo tanto a densidade como o acúmulo de matéria seca. Quanto ao A. hispidum, ambos os métodos e doses não proporcionaram bom controle. Foi observado também que o papel utilizado como veículo do oxyfluorfen proporcionou redução na densidade de B. pilosa, E. indica, D. horizontalis e A. retroflexus e promoveu a germinação de S. rhombifolia e A. hispidum quando da avaliação aos DAA. Estes resultados demonstram a viabilidade de utilização de papel como veículo de aplicação do oxyfluorfen.A greenhouse assay was conducted to evaluate na alternative method for applying oxyfluorfen to control annual weeds. The experiment was in 3 x 2 factorial, in a completely randomized design, with three replications. The factors were: three doses of oxyfluorfen (0, 480 and 960g/ha and two methods to apply the herbicide to the soil surface