Weed Research Research Articles

The Slide Hammer Seeder: A Novel Tool for Planting Small Seeds

Many important herbs [e.g., mint (Mentha sp.), thyme (Thymus sp.)], underused and nutritious vegetables [e.g., purslane (Portulaca oleracea), amaranth (Amaranthus tricolor)], and important biological control plants [e.g., sweet alyssum (Lobularia maritima)] have small seeds (≤ 1.5-mm long) that are difficult to plant with raw (i.e., nonpelleted) seed using existing seeders. A novel tool known as the slide hammer (SH) seeder was developed for the precise seeding of raw seeds of small-seeded plants. The SH seeder is a jab-type planter made primarily from electrical conduit tubing and other materials that are inexpensive and readily available in a hardware store or on the Internet. The interchangeable seed hopper is made from a plastic snap cap vial that has one or more holes of varying diameter depending on the desired seeding rate and seed size. Seed forms a “bridge” above the hole in the vial until they are dislodged from the force of the SH that discharges seeds to fall to the soil. Detailed plans are provided for how to make and use the SH seeder. The fabrication time is 2 to 4 hours with a material cost of ≈$32. I determined the seed vial hole specifications for the precise seeding of a variety of small-seeded plants, including chives (Allium schoenoprasum), chinese chives (Allium tuberosum), basil (Ocimum basilicum), grain amaranth (Amaranthus sp.), sweet alyssum, purslane, creeping thyme (Thymus serpyllum), and spearmint (Mentha spicata) that ranged in size from ≈200 to 11,000 seeds per gram. The diameter of the hole that was suitable for discharging the seed from the vial was always larger than the average seed length, and the ratio of hole diameter to seed length ranged from 1.07 to 1.62. Seeding rate uniformity evaluations were conducted for these species using vials with one vs. two holes and showed that the seeding rate was higher by an average of 58% to 173% from a vial with two holes compared with one hole. For most plant species evaluated, the SH seeder was able to dispense as few as one to three seeds consistently. Seed discharge increased somewhat with increasing SH weight for all species evaluated. The SH seeder can be useful for interplanting sweet alyssum as an insectary plant for aphid (Aphidoidea) control between existing plants of organic lettuce (Lactuca sativa), and for intercropping cultivars of purslane as a novel vegetable in between transplanted organic broccoli (Brassica oleracea Italica group) plants. This novel seeding tool has many potential uses for direct, hand seeding in vegetable and herb production systems and in weed research trials. The seeder could be automated and made with a variety of alternative materials.

Editor‐in‐Chief to step down

I have taken the decision to step down from my post as Editor-in-Chief of Weed Research at the end of December 2018. I will have been at the helm of Weed Research for 13 stimulating years, but with grandchildren on hand, I recognise it is time the journal had new and younger blood. I will reflect further on my 13 years in a forthcoming final Editorial. I tendered my notice in June this year, giving 6 months for EWRS to appoint a new Editor-in-Chief. Details will shortly be available and I will post information on the journal Twitter feed. Meanwhile, if you are interested, please contact the Chair of the Editorial Board, Dr Paul Hatcher (p.e.hatcher@reading.ac.uk). The role has been a rewarding one, not least because of the support of dedicated editors, reviewers (see the end of this issue) and stimulating science from so many authors. Thank you.

Reviewers for Weed Research

Weed ResearchVolume 58, Issue 6 p. 475-476 Miscellaneous Reviewers for Weed Research Jon Marshall, Jon Marshall Editor-in-Chief 19 October 2018Search for more papers by this author Jon Marshall, Jon Marshall Editor-in-Chief 19 October 2018Search for more papers by this author First published: 20 November 2018 https://doi.org/10.1111/wre.12340Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume58, Issue6December 2018Pages 475-476 RelatedInformation

The wide world of weed research

As Canada lifts most of its restrictions on studying cannabis, here’s a look at how the rest of the world is faring. As Canada lifts most of its restrictions on studying cannabis, here’s a look at how the rest of the world is faring.

DISTRIBUTION MAPPING OF GLYPHOSATE-RESISTANT Eleusine indica IN SERDANG BEDAGAI REGENCY

The presence of Eleusine indica from oil palm plantations in Serdang Bedagai Regency has never been overall reported glyphosate-resistant. This study aims to distribution mapping and resistance classification of E. indica population to glyphosate herbicide of oil palm plantations in Serdang Bedagai Regency. This research was conducted on Weed Research Center Land in Faculty of Agriculture, Universitas Sumatera Utara in October 2016 to August 2017. This research used glyphosate herbicide with the recommended dose at 720 g ai ha-1 and three replications. Population ESU0 (from Politeknik Negeri Medan Ball Field) as a comparison. Data analysis using IBM SPSS Statistics 20 software. The results showed there E. indica population classified as glyphosate-resistant amount 89.36% (42 population), classified as glyphosate-resistant moderate amount 10,64% (5 population) and there is no population glyphosate-susceptible on oil palm plantations in Serdang Bedagai Regency of recommended dose at 720 g ai ha-1.

DISTRIBUTION MAPPING OF GLYPHOSATE-RESISTANT Eleusine indica IN SERDANG BEDAGAI REGENCY

The presence of Eleusine indica from oil palm plantations in Serdang Bedagai Regency has never been overall reported glyphosate-resistant. This study aims to distribution mapping and resistance classification of E. indica population to glyphosate herbicide of oil palm plantations in Serdang Bedagai Regency. This research was conducted on Weed Research Center Land in Faculty of Agriculture, Universitas Sumatera Utara in October 2016 to August 2017. This research used glyphosate herbicide with the recommended dose at 720 g ai ha-1 and three replications. Population ESU0 (from Politeknik Negeri Medan Ball Field) as a comparison. Data analysis using IBM SPSS Statistics 20 software. The results showed there E. indica population classified as glyphosate-resistant amount 89.36% (42 population), classified as glyphosate-resistant moderate amount 10,64% (5 population) and there is no population glyphosate-susceptible on oil palm plantations in Serdang Bedagai Regency of recommended dose at 720 g ai ha-1.

Sebaran Populasi dan Klasifikasi Resistensi Eleusine indica terhadap Glifosat pada Perkebunan Kelapa Sawit di Kabupaten Deli Serdang

<p>Eleusine indica populations on oil palm plantations in Deli Serdang Regency have not been reported to be resistant to glyphosate. This study was aimed to report distribution and resistance classification of E. indica population on oil palm plantations in Deli Serdang Regency. The research was conducted on Weed Research Center in Faculty of Agriculture, Universitas Sumatera Utara from October 2016 until August 2017. This research used Randomized Block Design with recommended dose at 720 g a.i.ha-1 of glyphosate and three replications. Population ESU0 (from Politeknik Negeri Medan Ball Field) as a comparison. Data on average survival, mortality, dry weight, resistance classification of E. indica were analyzeds using IBM SPSS Statistics 20 software. The results showed that there were 12 E. indica populations classified as glyphosate-resistant (56.52%), 7 glyphosate-resistant developing (30.43%), and 4 populations classified as glyphosate-susceptible (13.04%) with the recommended dose at 720 g a.i.ha-1 from oil palm plantations in Deli Serdang Regency.</p>

English

A field experiment was carried out at Agricultural Seed and Services Research Station in Zimbabwe to evaluate the response of maize inbred lines to different herbicide combinations. The trial was laid out in a 5×12 split plot design replicated three times. Herbicide combination was main plot factor with five levels; Hand-hoeing;metolachlor+ atrazine;metolachlor+ atrazine+ nicosulfuron; metolachlor+ atrazine+ halosulfuron and metolachlor +atrazine+ nicosulfuron+ halosulfuron. These combinations of herbicides have a broad spectrum activity and are able to control annual and perennial weeds with an inbred line as subplot factor with twelve levels; CML488, CML312, CML444, CML443, CM1, CML395, CZL0610, CZ3, CZL03014, L917 and N3.2.3.3. Data on germination, phytotoxicity, plant height, anthesis silking interval (ASI), ear height and grain yield were measured. There was a significant interaction (p 0.05) among herbicide combinations and maize inbred lines on plant height (week 12). That concluded metolachlor+ atrazine+ nicosulfuron and metolachlor +atrazine+nicosulfuron+ halosulfuron herbicides had a major effect on susceptible maize inbred lines. Inbred lines were grouped into three categories in relation to European Weed Research Council (EWRC) score, efficacy and survival rate into; tolerant (CML312, CML444, CML443 and CM3), medium resistant (CML395, CZL0610, NAW5885 and CZ3) and susceptible (CML488, CZL03014, L917 and N3.2.3.3). Therefore, the study recommends not using metolachlor+ atrazine+ nicosulfuron and metolachlor+ atrazine+ nicosulfuron+ halosulfuron herbicide combinations on susceptible maize inbred lines. Key words: Zea mays, inbred lines, herbicide combinations, metolachlor, atrazine, nicosulfuron.

SCREENING SINGLE RESISTANCE OF Eleusine indica ON OIL PALM PLANTATION IN PADANG LAWAS AND TAPANULI SELATAN REGENCY INDONESIA

Abstract: Eleusine indica population from several estates in Padang Lawas and Tapanuli Selatan Regency, Sumatera Utara Indonesia has never been reported to be resistant to glyphosate herbicide. This study aims at distribution mapping and resistance classification of Eleusine indica glyphosate-resistant populations from several estates in Padang Lawas and Tapanuli Selatan Regency, Sumatera Utara. This research was conducted at Weed Research Center of the Faculty of Agriculture, Universitas Sumatera Utara from October 2016 to August 2017. This research used glyphosate at the recommended rate of 720 g ai ha-1 and three replications. Population ESU0 (from Politeknik Negeri Medan Ball Field) as a comparison. Data analysis using t-test at the level of 5% with IBM SPSS Statistics 20 software. The results showed 22 populations in Padang Lawas Regency have 8 populations classified as glyphosate-resistant (36.36%), 8 populations classified as developed-resistant (36.36%), and 6 populations classified as glyphosate-susceptible (27.27%). While from 6 populations in Tapanuli Selatan Regency have 5 populations classified as glyphosate-resistant (83.33%), 1 populations classified as developed-resistant (16.67%), and 0 populations classified as glyphosate-susceptible (0%). Keywords: glyphosate, goosegrass, oil palm plantation, resistance.

Statistical approaches in weed research: choosing wisely

Conceitos e métodos estatísticos possuem papel fundamental para a sociedade, e a análise estatística de dados demanda considerável esforço e conhecimento humano. Por um lado, computadores e softwares estatísticos permitem que virtualmente qualquer pessoa possa escolher e executar testes estatísticos, mas por outro lado qualquer pesquisador, professor, estudante ou profissional pode utilizar estes softwares, mesmo os que não possuem conhecimentos estatísticos básicos para testar seus dados, produzindo com frequência análises estatísticas com algum tipo de incorreção. Objetiva-se com a presente revisão demonstrar como a escolha do método estatístico na ciência das plantas daninhas pode criar um viés na interpretação da eficiência de herbicidas, e impactar sua recomendação. Os problemas discutidos são ilustrados com base em dados de experimentos reais de campo. Propomos pequenas alterações na forma atual de análise de dados para auxiliar a reduzir a má interpretação de dados e a equivocada recomendação de herbicidas com base em sua eficiência em experimentos. Grande parte dos resultados de estudos com herbicidas parece estar embasado em experimentos sem o devido poder estatístico, logo sujeitos a fornecer informações com viés. A escolha por métodos estatísticos falhos, especialmente os baseados no valor-p (ANOVA e testes post-hoc), podem estar levando a conclusões equivocadas mesmo em experimentos com herbicidas corretamente conduzidos. Propõe-se o uso de intervalos de confiança para análise de dados qualitativos e quantitativos, junto ao adequado número de amostragens (“n”).

Carlos L. Ballaré.

Carlos L. Ballaré.

Energy content of hybrid Rumex patienta L. x Rumex tianschanicus A. Los. (Rumex OK 2) samples from autumn months

Energy content of hybrid Rumex patienta L. x Rumex tianschanicus A. Los. (Rumex OK 2) samples from autumn months

Reviewing research priorities in weed ecology, evolution and management: a horizon scan.

SummaryWeedy plants pose a major threat to food security, biodiversity, ecosystem services and consequently to human health and wellbeing. However, many currently used weed management approaches are increasingly unsustainable. To address this knowledge and practice gap, in June 2014, 35 weed and invasion ecologists, weed scientists, evolutionary biologists and social scientists convened a workshop to explore current and future perspectives and approaches in weed ecology and management. A horizon scanning exercise ranked a list of 124 pre‐submitted questions to identify a priority list of 30 questions. These questions are discussed under seven themed headings that represent areas for renewed and emerging focus for the disciplines of weed research and practice. The themed areas considered the need for transdisciplinarity, increased adoption of integrated weed management and agroecological approaches, better understanding of weed evolution, climate change, weed invasiveness and finally, disciplinary challenges for weed science. Almost all the challenges identified rested on the need for continued efforts to diversify and integrate agroecological, socio‐economic and technological approaches in weed management. These challenges are not newly conceived, though their continued prominence as research priorities highlights an ongoing intransigence that must be addressed through a more system‐oriented and transdisciplinary research agenda that seeks an embedded integration of public and private research approaches. This horizon scanning exercise thus set out the building blocks needed for future weed management research and practice; however, the challenge ahead is to identify effective ways in which sufficient research and implementation efforts can be directed towards these needs.

Statistical approaches in weed research: choosing wisely

Conceitos e métodos estatísticos possuem papel fundamental para a sociedade, e a análise estatística de dados demanda considerável esforço e conhecimento humano. Por um lado, computadores e softwares estatísticos permitem que virtualmente qualquer pessoa possa escolher e executar testes estatísticos, mas por outro lado qualquer pesquisador, professor, estudante ou profissional pode utilizar estes softwares, mesmo os que não possuem conhecimentos estatísticos básicos para testar seus dados, produzindo com frequência análises estatísticas com algum tipo de incorreção. Objetiva-se com a presente revisão demonstrar como a escolha do método estatístico na ciência das plantas daninhas pode criar um viés na interpretação da eficiência de herbicidas, e impactar sua recomendação. Os problemas discutidos são ilustrados com base em dados de experimentos reais de campo. Propomos pequenas alterações na forma atual de análise de dados para auxiliar a reduzir a má interpretação de dados e a equivocada recomendação de herbicidas com base em sua eficiência em experimentos. Grande parte dos resultados de estudos com herbicidas parece estar embasado em experimentos sem o devido poder estatístico, logo sujeitos a fornecer informações com viés. A escolha por métodos estatísticos falhos, especialmente os baseados no valor-p (ANOVA e testes post-hoc), podem estar levando a conclusões equivocadas mesmo em experimentos com herbicidas corretamente conduzidos. Propõe-se o uso de intervalos de confiança para análise de dados qualitativos e quantitativos, junto ao adequado número de amostragens (“n”).

Weed research status, challenges, and opportunities in China

Weeds are a major constraint to crop production, which is of crucial importance for food security in China given its 1.37 billion population. In recent years, an increasing number of herbicide resistant weeds and invasive alien plants have become prevalent and challenging to manage in China as elsewhere in the world. In this review, we provide an overview of several key facets of weed science research in China, including (i) weed community shifts as a result of cropping system and weed management changes, (ii) the status of invasive weeds, (iii) weed management options for the increasing number of herbicide resistant weeds, and (iv) the challenges and opportunities in weed research in China. Invasive weeds in tandem with changes in cropping systems have significantly altered weed communities in crops such as rice (Oryza sativa L.), wheat (Triticum aestivum L.), maize (Zea mays L.), soybean [Glycine max (L.) Merr.], cotton (Gossypium hirsutum L.), and oilseed rape (Brassica napus L.). At present, 30 weed species have evolved resistance to 11 herbicide sites of action that includes 48 commonly used herbicides. Although tactics such as crop rotation and biological control have been used to manage some weeds in China, weed control has and continues to rely primarily on herbicides. Research priorities for weed management include developing and implementing a preventive risk assessment framework and a better understanding of the mechanisms that allow some alien weeds to be highly aggressive and difficult to manage. Moreover, the development and evaluation of additional weed management tactics such as breeding competitive crop cultivars, straw mulching, optimizing water management, and site-specific fertilizer and herbicide applications warrant further study. The use of an integrated weed management approach in coming years will rely heavily on a more in-depth understanding of the biological and ecological principles governing weed population dynamics. Approaches such as herbicide resistance weed management (HRWM) programs in tandem with conservation agriculture (CA) can be employed to develop sustainable weed management strategies in cropping systems.

Weed research issues, challenges, and opportunities in India

Agriculture is the major source of livelihood for nearly half of the Indian population. However, the productivity of crops is much lower than many countries and needs enhancement to produce ∼400 million tons of food grains for meeting food demands of a population of 1.7 billion by 2050. Diverse climatic conditions in India favor the most adopted weeds to prevail and cause severe crop yield losses. Weeds also degrade quality of the produce, raise cost of production; harbor and serve as alternate hosts to several insect pests and diseases. Parthenium hysterophorus L.; Phalaris minor Retz.; Leptochloa chinensis (L.) Nees.; Echinochloa spp.; weedy rice; Lantana camara L.; Chromolaena odorata (L.) R.M. King & H. Rob.; Mikania micrantha Kunth., are a few of many major weeds of concern currently in India. Weed management in India is critical to improve crops productivity by minimizing weeds caused crop yield losses and to alleviate other adverse effects of weeds in different ecosystems. In spite of the progress made in evolving weed management technologies for different crops and other ecosystems, weeds continue to be a concern in varying ecosystems. The real challenges of Indian weed research are: managing weeds in small farms; non availability of labor and mechanical tools; inadequate information on weed biology and shifts in weed flora; herbicide resistant weeds; lack of understanding on the impact of climate change on weeds and weed control; popularizing integrated weed management with herbicides use by ensuring safe use to avoid adverse effect on human health, environment and avoid weeds developing herbicide resistance and prevention of entry and management of alien invasive weeds. The greatest opportunity of Indian weed science is the potentiality of appropriate weed management technologies to substantially improve the crops productivity. Thus, weed scientists have a greater role to play in the development, popularization and adoption of location specific effective, economical and eco-friendly weed management technologies for different ecosystems of India.

Broadening the scope of Weed Research

The Editorial Board of Weed Research conducted an online discussion during the summer of 2017, reviewing the status of the journal and responding to questions on the impact, scope and potential improvements for the journal for the future. My vision as Editor-in-Chief has always been that Weed Research should be the journal of choice for weed scientists and for it to have the highest impact it can. Whilst the impact metrics for the journal have been reasonable in the past, the last three years have seen a decline that needs addressing. Authors look to publish in the highest impact journals possible and the journal needs to act to improve its impact. Impact is largely down to citation metrics these days, so factors such as excellence, likely citation rate and attracting submissions of the best papers, including reviews, need careful attention. Amongst the Board, there is also clear concern that we need to broaden the scope of the journal to address some of these issues. It is essential that any changes to the journal are placed in the current scientific and publishing context. Scientifically, the traditional areas that the journal covers, notably weed biology and weed management in agriculture, are now mature science. As our vision is to publish work that advances science, we are at a pivotal moment for weed science and for the journal. The challenges we face as weed scientists are that the traditional approaches with simple control technologies are not sustainable, yet we need to feed an increasing world population. Pressures on land to achieve multifunctionality and to mitigate human impact on the planet are building. Increasingly, for production agriculture, horticulture and forestry, integrated crop management is required. This needs to be built around primary plant production and its interactions with biotic, abiotic, social and economic environments to develop long-term sustainability. Thus, we are expanding the scope of the journal to cover cross-cutting issues in integrated crop management and the interactions with the range of disciplines across production and crop protection, as well as integrated weed management. We invite scientists to submit manuscripts that address such issues and we welcome reviews on integrated crop and weed management. I am particularly keen that the journal covers uncropped land in its broadest sense, including natural and semi-natural habitats, alongside the ecology of agriculture, horticulture and forestry. The journal already covers vegetation management in its broadest sense, reflected in the strap line a ‘journal of weed biology, ecology and vegetation management’. Whilst this clearly covers invasive plants in all ecosystems, and many papers are published on such topics in Weed Research, I notice that there are relatively few contributions from forestry, horticulture, amenity and urban systems, or from rangelands or conservation sites. We welcome submissions from across these systems that address aspects of the interactions of the botanical components. Ecologically, plants form the primary producers upon which all food chains are based. The positive role of wild plants in production systems has only been appreciated relatively recently and we invite submissions that explore the services and disservices of such species and not just in production systems. We should also consider the plant interactions between the varied components of landscape mosaics, at scales ranging from dispersal dynamics at field edges to global spread. We also should cover conservation management and habitat recreation in the context of vegetation management. Thus, the scope of the journal will cover a broader range of topics than weed biology and control and better reflect the interests of the readership and the European Weed Research Society. In a previous editorial (2015; Weed Research 55, 437–440), we discussed the aims and policies of the journal. We will be relaxing those policies in relation to specific topics, such as allelopathy and herbicide resistance, to encourage more submissions. However, we will retain our aim of only publishing novel and innovative work. Further editorials in 2018 will discuss the means of increasing impact beyond broadening the scope of the journal, the role of the journal as a service for authors and the promotion of openness across the Editorial Board's work. Meanwhile, if you would like to comment on any aspect of the journal, please email me.

Technical abbreviations for use in Weed Research

Technical abbreviations for use in <i>Weed Research</i>

Adoption of integrated weed management practices correlates with farmers profile characteristics

This study explored the adoption level towards integrated weed management (IWM) practices and the associated relationship with various profile characteristics of 108 farmers from 12 villages of 6 blocks of Jabalpur district of Madhya Pradesh with an ex-facto sampling design. A list of various IWM practices in major crops suited to the study area and recommended by ICAR-Directorate of Weed Research, Jabalpur, was prepared after consultation with experts in the area. It was found that majority of the respondents had medium extent of adoption of IWM practices with reference to rice (56%), soybean (49%), greengram (50%) and wheat (55%). A positive and significant correlation between level of adoption of respondents on overall IWM practices with other variables viz. age, education, farm size, training, extension contact, mass media exposure, input availability and innovativeness were noticed.

Weed control in sesame with pre-emergence herbicides

Pendimethalin, imazethapyr, metribuzin, oxyfluorfen, imezemox were evaluated as pre-emergence herbicides in sesame during summer season of 2013 and 2014 at ICAR-Directorate of Weed Research, Jabalpur. All the herbicides reduced the weed population significantly as compared with weedy check but delayed the germination of sesame and caused sesame injury. Among all the herbicides, pendimethalin alone and in combination with lower dose of imazethapyr caused less injury to the sesame and produced higher sesame yield. None of the herbicides surpassed the yield what was achieved with 2 HW.