Journal articles on the topic 'Weeds, spain'
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1
Saavedra, M., J. Cuevas, J. Mesa-García, and L. García-Torres. "Grassy weeds in winter cereals in southern Spain." Crop Protection 8, no. 3 (June 1989): 181–87. http://dx.doi.org/10.1016/0261-2194(89)90024-0.
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Gandía, María Luisa, Carlos Casanova, Francisco Javier Sánchez, José Luís Tenorio, and María Inés Santín-Montanyá. "Arable Weed Patterns According to Temperature and Latitude Gradient in Central and Southern Spain." Atmosphere 11, no. 8 (August 13, 2020): 853. http://dx.doi.org/10.3390/atmos11080853.
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(1) Background: In agro-ecosystems, the success of the crops has a strong connection to biodiversity in the landscape. In the face of climate change, it is important to understand the response to environmental variation of weed species by means of their distribution. In the last century, biodiversity has been impacted due to a variety of stresses related to climate change. Although the composition of vegetation tends to change at a slower rate than climate change, we hypothesize species present in weed communities are distributed in diverse patterns as a response to the climate. Therefore, the general aim of this paper is to investigate the effect of temperature, using latitude as an indicator, on the composition and distribution of weed communities in agro-ecosystems. (2) Methods: Weeds were monitored in georeferenced cereal fields which spanned south and central Spanish regions. The graphic representation according to latitude allowed us to identify groups of weeds and associate them to a temperature range. We classified weeds as generalist, regional, or local according to the range of distribution. (3) Results: The monitoring of species led to the classification of weeds as generalist, regional or local species according to latitude and associated temperature ranges. Three weed species that were present in all latitude/temperature regions, were classified as generalist (Linaria micrantha (Cav) Hoffmanns & Link, Sonchus oleraceous L., and Sysimbrium irium L.). The species were classified as regional or local when their presence was limited to restricted latitude/temperature ranges. One weed, Stellaria media (L.) Vill., was considered a local species and its distribution dynamics can be considered an indicator of temperature. (4) Conclusions: The novel methodology used in this study to assign weed distribution as an indicator of climatic conditions could be applied to evaluate climate gradients around the world.
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SALVA, A. PUJADAS, and J. E. HERNANDEZ BERMEJO. "Floristic composition and agricultural importance of weeds in southern Spain." Weed Research 28, no. 3 (June 1988): 175–80. http://dx.doi.org/10.1111/j.1365-3180.1988.tb01603.x.
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Fernández-Sanz, Ana M., M. Rosario Rodicio, and Ana J. González. "Biochemical Diversity, Pathogenicity and Phylogenetic Analysis of Pseudomonas viridiflava from Bean and Weeds in Northern Spain." Microorganisms 10, no. 8 (July 29, 2022): 1542. http://dx.doi.org/10.3390/microorganisms10081542.
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Pseudomonas viridiflava was originally reported as a bean pathogen, and subsequently as a wide-host range pathogen affecting numerous plants species. In addition, several authors have reported the epiphytic presence of this bacterium in “non-host plants”, which may act as reservoir of P. viridiflava and source of inoculum for crops. A new biotype of this bacterium, showing an atypical LOPAT profile, was found in Asturias, a Northern region of Spain, causing significant damage in beans, kiwifruit, lettuce, and Hebe. In order to investigate the involvement of weeds in bean disease, samples were collected from beans and weeds growing in the same fields. A total of 48 isolates of P. viridiflava were obtained, 39 from weeds and 9 from beans. 48% and 52% of them showed typical (L− O− P+ A− T+) and atypical (L+ O− P v A− T+) LOPAT profiles, and they displayed high biochemical diversity. Regarding virulence factors, the T-PAI and S-PAI pathogenicity islands were found in 29% and 70.8% of the isolates, 81.2% displayed pectinolytic activity on potato slices, and 59% of the weed isolates produced symptoms after inoculation on bean pods. A phylogenetic tree based on concatenated rpoD, gyrB, and gltA sequences separated the strains carrying S-PAI and T-PAI into different clusters, both containing isolates from beans and weeds, and pathogenic as well as non-pathogenic strains. Closely related strains were found in the two hosts, and more than half of the weed isolates proved to be pathogenic in beans. This is consistent with the role of weeds as a reservoir and source of inoculum for bean infection. Detection of P. viridiflava in weeds throughout the year further supports these roles.
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Gómez de Barreda, Diego, Gabriel Pardo, José María Osca, Mar Catala-Forner, Silvia Consola, Irache Garnica, Nuria López-Martínez, José Antonio Palmerín, and Maria Dolores Osuna. "An Overview of Rice Cultivation in Spain and the Management of Herbicide-Resistant Weeds." Agronomy 11, no. 6 (May 28, 2021): 1095. http://dx.doi.org/10.3390/agronomy11061095.
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Spain is the second highest rice-producing country in the European Union, with approximately 105,000 ha used to grow this crop. The major rice-producing regions in Spain are Andalusia, Extremadura, Catalonia, and Valencia, followed by Aragon and Navarre. The main soil texture throughout Spanish rice areas is silty clay loam, with alkaline soils (pH > 7.5)—except in the Extremadura area (pH = 5.5–6)—and a low organic matter content. Water quality in terms of salinity is acceptable, although in some coastal rice areas salinity issues occasionally appear to be a determining factor for high yield achievement. According to a survey carried out on farmers and technicians, the most problematic weeds found in rice crops today in Spain are Echinochloa spp., Leptochloa spp., and Cyperus difformis. Most of the currently authorized herbicides can be classified according to two modes of action: ALS-inhibiting and ACCase-inhibiting. Repeated field applications of herbicides with the same mode of action have resulted in the selection of herbicide-resistant weeds. At present, resistance has been confirmed in different regions of Spain to ALS inhibitors in Echinochloa spp., Leptochloa spp., and Cyperus difformis, and to ACCase inhibitors in Echinochloa spp. and Leptochloa spp. The mechanism of resistance in these species is a mutation in the target site of these herbicides. Several mutations have been found in the ALS gene, both in Echinochloa spp. and Cyperus difformis, distributed in the different rice-growing regions considered in this work. ACCase gene mutations have been mainly found in Leptochloa spp. individuals from Extremadura and Valencia. These different mutations have resulted in different patterns of cross-resistance to ALS- and ACCase-inhibiting herbicides. It is likely that the repeated use of these two modes of action in rice will result in the evolution of more resistant weed populations. The possible availability of new herbicides with alternative modes of action in a short space of time seems very limited, suggesting the need for a more appropriate use of the available alternative strategies (crop rotation, dry sowing, manual weeding, etc.). This work presents a review of the main characteristics of rice cultivation in Spain, emphasizing the current problems in this crop and the management of herbicide-resistant weeds.
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Villegas-Fernández, Ángel M., Ahmed A. Amarna, Juan Moral, and Diego Rubiales. "Intercropping as a Strategy for Weed Management in Faba Bean (Vicia faba L.)." Agronomy 14, no. 6 (May 30, 2024): 1170. http://dx.doi.org/10.3390/agronomy14061170.
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Faba bean is an important legume crop worldwide, which is grown both for food and feed. As for many legume crops, postemergence weed control is difficult. The aim of this work was to assess the potential of intercropping in weed management by assessing the effect of mixing faba bean with different crops (wheat, barley, and pea) on weeds in the South of Spain. Four field trials were conducted over four consecutive seasons, and the results found that the addition of alternate intercropping of faba bean and barley achieved high levels of weed control, both for coverage and biomass (92.7% and 76.6%, respectively). Intercropping with wheat did not reduce weed coverage but did decrease weed biomass by 46.1% as compared with the faba bean monocrop. Intercropping with pea did not provide significant reductions in weed coverage or weed biomass. The diversity of the weed community was not altered by the different crop combinations tested. Additional experiments under controlled conditions were carried out to determine the possible role of barley allelopathy in weed suppression. A strong allelopathic effect entailing a reduction in the number of plants and biomass was detected for four weeds including Sinapis arvensis, Polypogon monspeliensis, Matricaria camomilla, and Medicago truncatula. It can be concluded that intercropping faba bean with barley is an excellent strategy for weed control in Southern Spain.
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de Castro, Ana-Isabel, Montserrat Jurado-Expósito, María-Teresa Gómez-Casero, and Francisca López-Granados. "Applying Neural Networks to Hyperspectral and Multispectral Field Data for Discrimination of Cruciferous Weeds in Winter Crops." Scientific World Journal 2012 (2012): 1–11. http://dx.doi.org/10.1100/2012/630390.
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In the context of detection of weeds in crops for site-specific weed control, on-ground spectral reflectance measurements are the first step to determine the potential of remote spectral data to classify weeds and crops. Field studies were conducted for four years at different locations in Spain. We aimed to distinguish cruciferous weeds in wheat and broad bean crops, using hyperspectral and multispectral readings in the visible and near-infrared spectrum. To identify differences in reflectance between cruciferous weeds, we applied three classification methods: stepwise discriminant (STEPDISC) analysis and two neural networks, specifically, multilayer perceptron (MLP) and radial basis function (RBF). Hyperspectral and multispectral signatures of cruciferous weeds, and wheat and broad bean crops can be classified using STEPDISC analysis, and MLP and RBF neural networks with different success, being the MLP model the most accurate with 100%, or higher than 98.1%, of classification performance for all the years. Classification accuracy from hyperspectral signatures was similar to that from multispectral and spectral indices, suggesting that little advantage would be obtained by using more expensive airborne hyperspectral imagery. Therefore, for next investigations, we recommend using multispectral remote imagery to explore whether they can potentially discriminate these weeds and crops.
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Agustí-Brisach, C., D. Gramaje, M. León, J. García-Jiménez, and J. Armengol. "Evaluation of Vineyard Weeds as Potential Hosts of Black-Foot and Petri Disease Pathogens." Plant Disease 95, no. 7 (July 2011): 803–10. http://dx.doi.org/10.1094/pdis-12-10-0888.
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Weeds were sampled in grapevine rootstock mother fields, open-root field nurseries, and commercial vineyards of Albacete, Alicante, Castellón, Murcia, and Valencia provinces in Spain between June 2009 and June 2010 and evaluated as potential hosts of black-foot and Petri disease pathogens. Isolations were conducted in the root system and internal xylem tissues for black-foot and Petri disease pathogens, respectively. Cylindrocarpon macrodidymum was successfully isolated from the roots of 15 of 19 weed families evaluated and 26 of 52 weed species. Regarding Petri disease pathogens, one isolate of Phaeomoniella chlamydospora was obtained from Convolvulus arvensis, and three isolates of Cadophora luteo-olivacea were obtained from Bidens subalternans, Plantago coronopus, and Sonchus oleraceus. Pathogenicity tests showed that Cylindrocarpon macrodidymum isolates obtained from weeds were able to induce typical black-foot disease symptoms. When inoculated in grapevines, isolates of Cadophora luteo-olivacea and Phaeomoniella chlamydospora were also shown to be pathogenic on grapevine cuttings. Our ability to recover grapevine pathogens from vineyard weeds and to demonstrate pathogenicity of recovered strains on grape suggests that these weeds may serve as a source of inoculum for infection of grapevine.
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Montull, José María, and Joel Torra. "Herbicide Resistance Is Increasing in Spain: Concomitant Management and Prevention." Plants 12, no. 3 (January 19, 2023): 469. http://dx.doi.org/10.3390/plants12030469.
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Herbicide-resistant weeds currently challenge sustainable food production in almost all cropping systems in Europe. Herbicide resistance is increasing, and some European countries are among the most affected globally, such as Spain and France. This situation is worsening not only due to herbicide use restrictions but also due to climate change, rendering Mediterranean countries such as Spain particularly susceptible. Therefore, focus should be aimed at preventive measures, which include those not only based on integrated weed management strategies but also based on a very good knowledge of the biology and ecology of each weed species. The main objective of this review is to provide an overview of potential future herbicide-resistant cases that can evolve in the near future in Europe. We use Spain as the case study, as it is the most affected country in Europe and because it is at risk due to global warming. For different resistant cases detailed on a crop basis, adequate prevention and management measures will be provided in order to avoid resistance evolution relative to the sites of action that are most likely to generate resistant biotypes due to expected high selection pressures.
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Bautista, Alberto San, Daniel Tarrazó-Serrano, Antonio Uris, Marta Blesa, Vicente Estruch-Guitart, Sergio Castiñeira-Ibáñez, and Constanza Rubio. "Remote Sensing Evaluation Drone Herbicide Application Effectiveness for Controlling Echinochloa spp. in Rice Crop in Valencia (Spain)." Sensors 24, no. 3 (January 25, 2024): 804. http://dx.doi.org/10.3390/s24030804.
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Rice (Oryza sativa L.) is a staple cereal in the diet of more than half of the world’s population. Within the European Union, Spain is a leader in rice production due to its climate and tradition, accounting for 26% of total EU production in 2020. The Valencian rice area covers around 15,000 hectares and is strongly influenced by biotic and abiotic factors. An important biotic factor affecting rice production is weeds, which compete with rice for sunlight, water and nutrients. The dominant weed in Spain is Echinochloa spp., although wild rice is becoming increasingly important. Rice cultivation in Valencia takes place in the area of L’Albufera de Valencia, which is a natural park, i.e., a special protection area. In this natural area, the use of phytosanitary products is limited, so it is necessary to use the minimum amount possible. Therefore, the objective of this work is to evaluate the possibility of using remote sensing effectively to determine the effectiveness of the application of the herbicide cyhalofop-butyl by drone for the control of Echinochloa spp. in rice crops in Valencia. The results will be compared with those obtained by using sterilisation machines (electric backpack sprayers) to apply the herbicide. To evaluate the effectiveness of the application, the reflectance obtained by the satellite sensors in the red and near infrared (NIR) wavelengths, as well as the normalised difference vegetation index (NDVI), were used. The remote sensing results were analysed and complemented by the number of rice plants and weeds per area, plant dry weight, leaf area, BBCH phenological state, SPAD index values, chlorophyll content and relative growth rate. Remote sensing is validated as an effective tool for determining the efficacy of an herbicide in controlling weeds applied by both the drone and the electric backpack sprayer. The weeds slowed down their development after the treatment. Depending on the phenological state of the crop and the active ingredient of the herbicide, these results are applicable to other areas with different climatic and environmental conditions.
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Garcia De Arevalo, Rafael C., Carmen A. Lusarreta, Carmen B. Neyra, Mercedes A. Sanchez, and Pedro J. H. Algarra. "Chemical Control of Annual Weeds in Field Beans (Vicia faba) in Central Spain." Weed Science 40, no. 1 (March 1992): 96–100. http://dx.doi.org/10.1017/s0043174500057027.
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Field studies were conducted over 3 yr to investigate the effect of chemicals on field beans density and weed control. Predominant weed species were common lambsquarters, fumitory, henbit, corn poppy, prostrate knotweed, and wild mustard. All herbicide treatments except linuron injured field beans. Mean field beans survival at harvest was 78% in alachlor and 84% in alachlor containing treatments. Only 5% survived atrazine at 1.9 kg ai ha−1. Ethalfluralin, pendimethalin, simazine, terbutylazine plus terbutryn, and trifluralin treatments produced plant survival values of 56, 82, 86, 74, and 71%, respectively. Chemical control of the main weed species overshadowed the detrimental effect on field beans density, and thus most herbicide treatments except alachlor resulted in increased dry beans yield. The best overall results occurred with linuron, simazine, terbuthylazine plus terbutryn, and pendimethalin which increased dry beans yields 76, 63, 56, and 40%, respectively, over the control plots. Common lambsquarters was the dominant weed, and prostrate knotweed and corn poppy were the most difficult and the easiest species to control, respectively.
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Cabrera-Pérez, Carlos, Francisco Valencia-Gredilla, Aritz Royo-Esnal, and Jordi Recasens. "Organic Mulches as an Alternative to Conventional Under-Vine Weed Management in Mediterranean Irrigated Vineyards." Plants 11, no. 20 (October 20, 2022): 2785. http://dx.doi.org/10.3390/plants11202785.
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Vineyard growth and grape yield can be significantly reduced by weeds, especially when these are located in the under-vine zone. Traditional weed management consists of recurrent tillage, which is associated with soil erosion and high fuel consumption, or herbicide applications, associated with damage to the environment and human health. In order to find alternative weed management methods, three field trials were carried out in Raimat (Lleida, NE Spain) with the aim of evaluating the suppressive effect of four mulches against weeds. Treatments included (1) straw mulch of Medicago sativa L., (2) straw mulch of Festuca arundinacea (L.) Schreb, (3) straw mulch of Hordeum vulgare L., (4) chopped pine wood mulch of Pinus sylvestris L., (5) mechanical cultivation and (6) herbicide application. The results showed that all mulches were efficient at controlling weeds (<20% of weed coverage) in the first year, compared with the two traditional methods, as long as the percentage of soil covered by mulches was high (>75%). In this way, pine mulch stood out above the straw mulches, as it achieved high soil cover during the three growing seasons of the study (>80%), with weed coverage values under 18%. This, together with the multiple benefits of mulches (improvements in the water balance and increases in soil organic matter, among others), make them a sustainable tool to be considered as an alternative to traditional under-vine weed management in vineyards.
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Alfaro-Fernández, A., C. Córdoba-Sellés, M. C. Cebrián, J. A. Herrera-Vásquez, J. A. Sánchez-Navarro, M. Juárez, A. Espino, R. Martín, and C. Jordá. "First Report of Tomato torrado virus on Weed Hosts in Spain." Plant Disease 92, no. 5 (May 2008): 831. http://dx.doi.org/10.1094/pdis-92-5-0831b.
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Tomato torrado virus (ToTV) is a recently identified Picorna-like virus that causes “torrado disease” in tomatoes (4). Typical symptoms of “torrado disease” seen in tomato crops (Solanum lycopersicum L. formerly Lycopersicon esculentum L.) were initially defined as yellow areas at the base of the leaflet that later developed into necrotic spots that sometimes abscised, leaving holes in the leaflet. Other plants showed extensive necrosis progressing from the base to the tip of the leaflet. Fruits were distorted with necrotic lines on the surface that often cracked. Affected plants had a burnt-like appearance and the production was seriously reduced. These symptoms have been observed in tomato crops in Murcia (Spain) and the Canary Islands (Spain) (1). To identify possible alternative hosts that may serve as virus reservoirs, samples of 72 different common weed species were collected in greenhouses in Murcia and the Canary Islands where “torrado disease” symptoms were observed in tomatoes. Forty-seven showed virus-like symptoms and 25 were asymptomatic. Symptoms included mild mosaic, blistering, vein clearing, interveinal yellowing, yellow spots, necrosis, leaf distortion, and curling. Samples were analyzed by one-step reverse transcription (RT)-PCR using primers specific for ToTV to amplify 580 bp of the polyprotein region of RNA2 (3) and dot-blot hybridization with a digoxygenin-labeled RNA probe complementary to the same portion of the ToTV genome. Twenty-two of the 72 weed samples belonging to Amaranthus sp. (Amaranthaceae); Spergularia sp. (Caryophyllaceae); Atriplex sp., Chenopodium ambrosioides L., Chenopodium sp., and Halogetum sativus (Loef. ex L.) Moq. (Chenopodiaceae); Senebiera didyma Pers. (Cruciferae); Malva sp. (Malvacae); Polygonum sp. (Polygonaceae); and Nicotiana glauca Graham and Solanum nigrum L. (Solanaceae) were positive for ToTV by molecular hybridization (10 samples) and RT-PCR (22 samples, including the samples positive by molecular hybridization). PCR products obtained from Atriplex sp. (Canary Islands) and S. didyma (Murcia) were sequenced (GenBank Accessions EU090252 and EU090253). BLAST analysis showed 99% identity to ToTV RNA2 sequence (GenBank Accession DQ388880). Two tomato plants were positive for ToTV by RT-PCR after mechanical back-inoculation, although no symptoms were observed. This study showed ToTV infects common weeds present in Spanish tomato crops. Recently, Trialeurodes vaporariorum has been reported to transmit ToTV (2), although the efficiency of transmission is unknown. The vector-assisted transmission of ToTV could explain the infection of weeds in affected greenhouses. To our knowledge, this is the first report of natural infection of weeds by ToTV. References: (1) A. Alfaro-Fernández et al. Plant Dis. 91:1060, 2007. (2) H. Pospieszny et al. Plant Dis. 91:1364, 2007. (3) J. Van der Heuvel et al. Plant Virus Designated Tomato Torrado Virus. Online publication. World Intellectual Property Organization WO/2006/085749, 2006. (4) M. Verbeek et al. Arch. Virol. 152:881, 2007.
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Torres-Pagán, Natalia, Marta Muñoz, Sara Barbero, Roberta Mamone, Rosa Peiró, Alessandra Carrubba, Adela M. Sánchez-Moreiras, Diego Gómez de Barreda, and Mercedes Verdeguer. "Herbicidal Potential of the Natural Compounds Carvacrol, Thymol, Eugenol, p-Cymene, Citral and Pelargonic Acid in Field Conditions: Indications for Better Performance." Agronomy 14, no. 3 (March 5, 2024): 537. http://dx.doi.org/10.3390/agronomy14030537.
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In recent years, interest in natural products with herbicidal activity as new tools for integrated weed management has increased. The European Union is demanding a reduction in the number of herbicides used, forbidding use of the most toxic ones, despite the problem of weed resistance increasing. Pelargonic acid (PA) is the only natural herbicide available in Spain. In this work, two field assays were performed with the natural compounds carvacrol (CAR), citral (CIT), eugenol (EUG), thymol (THY), p-cymene (P-CYM), (PA), and the combination of PA with CIT—all except P-CYM formulated by Seipasa—to test their herbicidal efficacy in real conditions. They were compared with commercial PA, glyphosate (GLY) and oxyfluorfen (OXY). In both experiments, GLY achieved the best weed control. Considering the natural herbicides, PA formulated by Seipasa and PA plus CIT were the most effective. From both experiments, some conclusions can be extracted for better herbicidal performance of natural products: (1) use products on sensitive weed species, (2) treat weeds at earlier phenological stages, (3) find the active doses in field conditions, (4) cover weeds well when treating, (5) ensure adequate formulation of products, and (6) develop a strategy for correct application.
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Santín-Montanyá, MI, AP Fernández-Getino, and JL Alonso-Prados. "Weed control in minor crops in Spain after adoption of European regulation 1107/2009/EC and directive 2009/128/EC." Outlook on Agriculture 46, no. 1 (March 2017): 66–73. http://dx.doi.org/10.1177/0030727017690661.
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Vegetable crops have become a source of great economic importance to many countries, particularly Spain. Crops should be protected from weeds in their early stages of development to prevent yield loss. It must be noted that there are limited registered herbicides for minor regional horticultural crops that generate little commercial interest. In this article, we discuss the implementation of European Regulation (Directive on Sustainable Use of Pesticides 2009/128/EC) in National Action Plans regarding horticultural minor use crops and the use of plant protection products with reference to evidence from Spain. The Spanish National Action Plan for the Sustainable Use of Plant Protection Products was implemented in 2012 by the Ministry of Agriculture, Food and Environment. Studies of the critical period of competition for weed control are a key component to help in developing a clear scheme that can be used for the design of effective integrated weed management programs. We highlight the urgent need for research and investigation into these areas and specifically ‘minor use’ crops due to the significant reduction of active substances approved in the European Union.
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José-María, L., L. Armengot, L. Chamorro, and F. Xavier Sans. "The conservation of arable weeds at crop edges of barley fields in northeast Spain." Annals of Applied Biology 163, no. 1 (June 11, 2013): 47–55. http://dx.doi.org/10.1111/aab.12032.
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San Martín, Carolina, Dionisio Andújar, Judit Barroso, Cesar Fernández-Quintanilla, and José Dorado. "Weed Decision Threshold as a Key Factor for Herbicide Reductions in Site-Specific Weed Management." Weed Technology 30, no. 4 (December 2016): 888–97. http://dx.doi.org/10.1614/wt-d-16-00039.1.
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The objective of this research was to explore the influence that weed decision threshold (DT; expressed as plants m−2), weed spatial distribution patterns, and spatial resolution of sampling have on potential reduction in herbicide use under site-specific weed management. As a case study, a small plot located in a typical corn field in central Spain was used, constructing very precise distribution maps of the major weeds present. These initial maps were used to generate herbicide prescription maps for each weed species based on different DTs and sampling resolutions. The simulation of herbicide prescription maps consisted of on/off spraying decisions based on information from two different approaches for weed detection: ground-based vs. aerial sensors. In general, simulations based on ground sensors resulted in higher herbicide savings than those based on aerial sensors. The extent of herbicide reductions derived from patch spraying was directly related to the density and the spatial distribution of each weed species. Herbicide savings were potentially high (up to 66%) with relatively sparse patchy weed species (e.g., johnsongrass) but were only moderate (10 to 20%) with abundant and regularly distributed weed species (e.g., velvetleaf). However, DT has proven to be a key factor, with higher DTs resulting in reductions in herbicide use for all the weed species and all sampling procedures and resolutions. Moreover, increasing DT from 6 to 12 plants m−2resulted in additional herbicide savings of up to 50% in the simulations for johnsongrass and up to 28% savings in the simulations for common cocklebur. Nonetheless, since DT determines the accuracy of patch spraying, the consequences of using higher DTs could be leaving areas unsprayed, which could adversely affect crop yields and future weed infestations, including herbicide-resistant weeds. Considering that the relationship between DT and accuracy of herbicide application depends on weed spatial pattern, this work has demonstrated the possibility of using higher DT values in weeds with a clear patchy distribution compared with weeds distributed regularly.
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Sacristán, Soledad, Aurora Fraile, and Fernando García-Arenal. "Population Dynamics of Cucumber mosaic virus in Melon Crops and in Weeds in Central Spain." Phytopathology® 94, no. 9 (September 2004): 992–98. http://dx.doi.org/10.1094/phyto.2004.94.9.992.
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Understanding epidemiology and evolution of plant viruses requires knowledge of their ecology: obtaining information about the dynamics and genetic structure of viral populations in their various hosts is necessary to analyze host specialization and to identify reservoirs and inoculum sources. We present here a 3-year analysis of the population dynamics of Cucumber mosaic virus (CMV) in Central Spain in weed hosts and melon. CMV infection in weed hosts was detected throughout the year and showed a clear seasonality, with maximum incidence of 20 to 30% in summer and autumn. The dynamics of CMV incidence were different in various weed habitats (i.e., fallow fields, edges, and wastelands), which differed in stability due to the degree of human intervention. CMV incidence in weed habitats was correlated with the amount of vegetation, estimated both as biomass and as soil cover by plants. CMV population dynamics in melon crops was unrelated to that in weed habitats. Genetic characterization by ribonuclease protection assays and biological characterization on differential hosts showed no significant differences in the frequency of genotypes or biotypes for CMV isolates from weeds or melon. Hence, different population dynamics in various hosts and habitats has not resulted in population differentiation, suggesting that migration between hosts and habitats prevents fragmentation of the population.
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Muñoz, Marta, Natalia Torres-Pagán, Amira Jouini, Fabrizio Araniti, Adela Sánchez-Moreiras, and Mercedes Verdeguer. "Control of Problematic Weeds in Mediterranean Vineyards with the Bioherbicide Pelargonic Acid." Agronomy 12, no. 10 (October 11, 2022): 2476. http://dx.doi.org/10.3390/agronomy12102476.
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Pelargonic acid (PA) is the only natural herbicide authorized for professional use in Spain. Incorporating PA into an integrated weed management strategy in vineyards may enable a more sustainable production method for grapes. In this work, PA of 55% concentration, formulated by a commercial company (PSEI), was evaluated and applied at 8, 10, 12, and 15 L/ha for weed control in Mediterranean vineyards during 2020 and 2021. A total of 22 different weed species, 16 dicotyledonous and 6 monocotyledonous, were identified in the experimental areas. Previously, greenhouse assays were performed against Avena fatua L. and Chenopodium album L. to determine the dose/response curves. PSEI proved to be a viable post-emergence herbicide with an efficacy of 40.79–80.90%, depending on the applied dose (higher doses were the most effective). Broader herbicidal activity (20% or more) was obtained against dicotyledonous weeds compared with monocotyledonous. The PA formulation was remarkable in achieving PSEI-similar effects as compared to the market reference but at lower concentrations (around 13% less PA) and doses (1–8 less L/ha). PA has proved to be a good candidate to control weeds in Mediterranean vineyards when used as a post-emergence broad-spectrum herbicide in the first stages of weed development.
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Garcia-Rellán, David, Mercedes Verdeguer, Adele Salamone, Maria Amparo Blázquez, and Herminio Boira. "Chemical Composition, Herbicidal and Antifungal Activity of Satureja cuneifolia Essential Oils from Spain." Natural Product Communications 11, no. 6 (June 2016): 1934578X1601100. http://dx.doi.org/10.1177/1934578x1601100636.
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The chemical composition of essential oils from Satureja cuneifolia growing in east Spain was analyzed by GC, GC/MS. Forty-five compounds accounting for 99.1% of the total oil were identified. Camphor (47.6%), followed by camphene (13.6%) were the main compounds. Their herbicidal and antifungal activity was tested in vitro against three weeds (Amaranthus hybridus, Portulaca oleracea and Conyza canadensis) and eleven common pathogenic or saprophytic fungi (Phytophthora citrophthora, P. palmivora, Pythium litorale, Verticillium dahlia, Rhizoctonia solani, Penicillium hirsutum, Colletotrichum gloeosporioides, Phaeoacremonium aleophilum, Phaemoniella chlamydospora, Cylindrocarpon liriodendri and C. macrodidymum). The essential oil was very active against A. hybridus and C. canadensis significantly inhibiting their germination and seedling growth. Minor activity was shown against P. oleracea, depending on the concentration applied. P. palmivora, P. citrophthora and Pa. chlamydospora were the most sensitive fungi to the treatment with the essential oil, whereas R. solani showed no inhibition. Results showed that S. cuneifolia essential oil could be used for biocontrol of weeds and fungal plant diseases.
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Font, M. I., M. Juárez, O. Martínez, and C. Jordá. "Current Status and Newly Discovered Natural Hosts of Tomato infectious chlorosis virus and Tomato chlorosis virus in Spain." Plant Disease 88, no. 1 (January 2004): 82. http://dx.doi.org/10.1094/pdis.2004.88.1.82a.
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Tomato chlorosis virus (ToCV) and Tomato infectious chlorosis virus (TICV) are emergent whitefly-transmitted criniviruses. ToCV and TICV were detected in Spain in 2000 (2) and 2001 (1), respectively. Both viruses infect tomato (Lycopersicon esculentum Mill) crops and cause symptoms of foliar chlorosis. ToCV is prevalent along the southern and eastern regions of Spain (provinces of Sevilla, Málaga, Almería, Murcia, Alicante, and Castellón), Balearic (Mallorca), and the Canary Islands (Tenerife and Gran Canaria). However, TICV only has been detected in the provinces of Murcia, Alicante, and Castellón in Spain. During the summer and autumn of 2002, abnormal interveinal reddening, yellowing symptoms, or both, were observed in plants of Chenopodium album L., C. murale L., and Solanum nigrum L. growing in or around tomato fields in Murcia and Almería provinces. To study the alternative hosts that may serve as virus reservoirs in areas where these viruses are prevalent, 62 samples of 42 common weed species were analyzed by reverse transcription-polymerase chain reaction using specific primers for ToCV and TICV (1). The 439-bp ToCV-specific DNA fragment was amplified in two S. nigrum samples from Alicante and Murcia provinces, and the 501-bp TICV-specific DNA fragment was amplified in one C. murale sample from Murcia, as well as in three C. album samples from Murcia and Alicante provinces. The DNA fragment amplified from the ToCV isolate was sequenced and showed 99 to 98% identity with the ToCV isolates (GenBank Accession Nos. AY048854 and AF234029) from Italy and Portugal, respectively. The DNA fragment amplified from TICV isolates were sequenced and showed 98% identity with the TICV isolate from Spain (GenBank Accession No. AF479662), confirming the diagnosis. Although the number of samples is not sufficient to conclude that we know, in a precise way, the role of weed reservoirs in TICV and ToCV epidemics in Spain, this study might contribute to a better understanding of the epidemiology of these viruses. To our knowledge this is the first report of these weeds as natural hosts of ToCV and TICV in Spain. References: (1) M. I. Font et al. Plant Dis. 86:696, 2002. (2) J. Navas-Castillo et al. Plant Dis. 84:835, 2000.
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Jordá, C., A. Lázaro Pérez, P. V. Martínez Culebras, and A. Lacasa. "First Report of Pepino mosaic virus on Natural Hosts." Plant Disease 85, no. 12 (December 2001): 1292. http://dx.doi.org/10.1094/pdis.2001.85.12.1292d.
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Pepino mosaic virus (PepMV) is a potexvirus recently identified as the causal agent of a new disease occurring in protected tomato (Lycopersicon esculentum Mill.) crops in the Netherlands (2). PepMV has been subsequently identified in England, Germany, Italy, Morocco, Portugal, and Spain. The new disease has become a serious problem for tomato production in Europe. Most infected tomato plants expressed leaf distortion, chlorosis, and yellow mosaic. Other plants expressed mosaic and bubbling of the leaf surface. Tomato fruits showing severe discoloration and mosaic were observed in protected tomato crops. Symptoms attenuated in tomato plants as the ambient temperature increased. At present, only Solanum muricatum Ait. (Peruvian pepino) and L. esculentum are affected by PepMV.To determine possible reservoir hosts for this virus, 70 samples from Amaranthus sp., A. viridis (L.) Britton et al., Chenopodium murale L., Convolvulus arvensis L., Malva parviflora L., Nicotiana glauca Grah., Polypogon monspeliensis (L.) Desf., Senecio vulgaris L., Sisybrium sp., Solanum nigrum L., and Sonchus oleraceus L. were analyzed. The plants were collected around greenhouses affected by PepMV from different regions in Spain (Murcia and Canary Islands). The samples were analyzed for PepMV by double-antibody sandwich enzyme-linked immunosorbent assay with a commercial antiserum (DSMZ AS-0554, Biologische Bundesantstal, Braunschweig, Germany). Only Amaranthus sp., M. parviflora, N. glauca, Solanum nigrum, and Sonchus oleraceus tested postive. The presence of PepMV in these weed species was confirmed by electron microscopy and reverse transcription-polymerase chain reaction using degenerate primers for potexvirus (1). All the hosts analyzed were asymptomatic. However, symptoms were reproduced by mechanically inoculating tomato plants with sap from naturally infected weeds. To our knowledge, this is the first report of natural infection of weeds by PepMV. References: (1) A. Gibbs et al. J. Virol. Methods 74:67, 1998. (2) R. A. A. Van der Vlugt et al. Plant Dis. 84:103, 2000.
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Enríquez-de-Salamanca, Álvaro. "Synanthropisation of coastal vegetation in southern Spain." Mediterranean Botany Online first (September 19, 2022): 1–18. http://dx.doi.org/10.5209/mbot.78628.
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Coastal dunes have high ecological value, but are often damaged or overexploited by beach tourism. The main problems for the vegetation of this ecosystem are the physical destruction and the synanthropisation, the latter due to the colonisation of both alien and apophyte species, favoured by human action. This study analyses the degree of synanthropisation of the vegetation of a stretch of coastline in southern Spain, by systematically surveying the flora present in six biotopes: beach, foredune, mid-dune, back-dune, creek and rocky area. The percentage of synanthropic species was 51%, of which 33% are apophytes, mainly ruderal species and weeds, and 18% are alien species, mostly from gardens adjacent to the coastal zone. The degree of synanthropisation varies by biotope, ranging from zero on the beach to 63% on the back-dune, with a marked increase from the beach inland. Richness and diversity is highest in biotopes with higher synanthropisation, but at the cost of lower naturalness. Measures need to be taken to protect coastal vegetation, both from destruction and synanthropisation.
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Guerrero-Casado, José, Antonio J. Carpio, Laura M. Prada, and Francisco S. Tortosa. "Short communication. The role of rabbit density and the diversity of weeds in the development of cover crops in olive groves." Spanish Journal of Agricultural Research 13, no. 3 (August 28, 2015): e03SC01. http://dx.doi.org/10.5424/sjar/2015133-7022.
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<p>Cover crops are an effective means to reduce soil erosion and to provide food and shelter for wildlife. However, in areas of intensive farming, which are characterised by the scarcity of weed communities, wild herbivores may focus their grazing on cover crops, which could make their implementation difficult. In this work, we test whether rabbit grazing can prevent the growth of herbaceous cover crops in olive groves in Southern Spain in addition to assessing the role of rabbit abundance and diversity of weeds in the development of cover crops. This question has been addressed by sowing <em>Bromus rubens</em> between the rows of five olive groves in Cordoba province (Spain). We then monitored the surface covered by <em>B. rubens,</em> along with both diversity of weed communities and rabbit abundance. Two rabbit exclusion areas were also placed in each olive grove in order to assess the impact of rabbits on the development of cover crops. Our results showed that the surface occupied by <em>B. rubens</em> was considerably higher in the rabbit exclusion areas (mean 56.8 ± 5.65 %) than in those areas in which they could feed (mean 35.6 ± 4.32 %). The coverage occupied by cover crops was higher in areas with lower rabbit density, although this relationship was modulated by the weed diversity index, since in areas with the same rabbit abundance the coverage was higher in those with a richer weed community. These findings suggest that high rabbit abundances can prevent the development of herbaceous cover crops in olive groves, particularly in areas in which alternative food resources (measured as weed diversity) are scarce.</p>
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Palma-Bautista, Candelario, Antonia M. Rojano-Delgado, Ignacio Dellaferrera, Jesús M. Rosario, Mario R. Vigna, Joel Torra, and Rafael de Prado. "Resistance Mechanisms to 2,4-D in Six Different Dicotyledonous Weeds Around the World." Agronomy 10, no. 4 (April 14, 2020): 566. http://dx.doi.org/10.3390/agronomy10040566.
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2,4-D resistance is increasing around the world due to both transgenic crops and resistance to other herbicides. The objective of the this study was to characterize the currently unknown mechanisms of 2,4-D resistance in five weed species from around the globe: Amaranthus hybridus (Argentina), Conyza canadensis (Hungary), Conyza sumatrensis (France), Hirschfeldia incana (Argentina) and Parthenium hysterophorus (Dominican Republic), using Papaver rhoeas (Spain) as a standard resistant (R) species. Dose-response trials using malathion and absorption, translocation and metabolism experiments were performed to unravel the resistance mechanisms. R plants produced at least 3-folds less ethylene than susceptible plants, confirming the resistance to 2,4-D, together with resistance factors >4. A. hybridus, P. hysterophorus and P. rhoeas showed both reduced translocation and enhanced metabolism. In the two Conyza sps., the only resistance mechanism found was enhanced metabolism. Malathion synergized with 2,4-D in all these species, indicating the role of cytochrome P450 in the herbicide degradation. In H. incana, reduced translocation was the only contributing mechanism to resistance. Among the six dicotyledonous weed species investigated, there was a differential contribution to 2,4-D resistance of enhanced metabolism and reduced translocation. Thus, extrapolating 2,4-D resistance mechanisms from one weed species to another is very risky, if even related.
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Royuela, Mercedes, Alberto Muñoz-Rueda, and Carmen Gonzalez-Murua. "Performance and Soil Persistence of Chlorsulfuron when Used for Wheat Production in Spain." Weed Science 38, no. 6 (November 1990): 546–52. http://dx.doi.org/10.1017/s0043174500051468.
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Chlorsulfuron was preemergence applied in field trials at La Coruña, Spain, at rates from 5 to 30 g ai ha−1(1987–88) and from 5 to 100 g ai ha−1(1988–89) for weed control in winter and spring wheat. Excellent control of broadleaf weeds was obtained in both; however, narrowleaf control at the last evaluation (heading) was poor. Chlorsulfuron at 30 g ha−1did not cause a residual problem in 1987–88, with only 0.24 μg kg−1of dry soil recovered after both a winter and spring wheat cropping season. However, chlorsulfuron persistence at the same rate was very high in the dry year 1988–89, with 0.43 μg kg−1and 0.53 μg kg−1recovered in winter and spring wheat, respectively. ‘Cardeno’ spring wheat showed no phytotoxic symptom at any rate of chlorsulfuron from 5 to 100 g ha−1. Its yield and yield components (spikes m−2, grain number spike−1, grain weight) were greater with all chlorsulfuron rates, but not in ‘Fiel’ winter wheat for rates of 30 g ha−1or higher.
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Valencia-Gredilla, Francisco, Aritz Royo-Esnal, Alejandro Juárez-Escario, and Jordi Recasens. "Different Ground Vegetation Cover Management Systems to Manage Cynodon dactylon in an Irrigated Vineyard." Agronomy 10, no. 6 (June 25, 2020): 908. http://dx.doi.org/10.3390/agronomy10060908.
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Ground cover management in vineyards in Spain is focused on minimizing soil erosion and compaction. Such practices have influenced the weed community structure in the inter-rows, contributing to the spread of the high noxious weed Cynodon dactylon (L.) Pers. This fact highlights the need for further investigation of the interaction between ground cover practices and weed control techniques. In this study, the effect of four different ground cover managements (M) in the inter-rows on C. dactylon population dynamics (changes in coverage and frequency) was assessed over three seasons (2015–2017): (M1) a no-till spontaneous vegetation ground cover managed by shredding; (M2) a no-till spontaneous vegetation ground cover managed by shredding plus herbicide application, (M3) tilled soil and spontaneous vegetation growing; and (M4) tilled soil and a barley cover crop seeded (Hordeum vulgare L.). Cynodon dactylon and the other weeds responded differently to the various weed control methods. After three seasons, the barley cover crop was the most efficient management system to control C. dactylon and other weeds. Final soil cover in barley cover crop and tilled soil with spontaneous vegetation were 0.5% and 1.1%, respectively, compared to 3.7% and 7.7% obtained by spontaneous vegetation shredded with and without herbicide application, respectively. In addition, total weed frequency varied from 9.7% for barley cover crop to 45.8% for spontaneous vegetation only shredded. Weed community composition changed due to the pressure exerted by each management and the adaptive strategy of the different species. This study highlights the importance of knowledge of how vegetation management influences weed flora to improve the sustainability of wine grape production systems.
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Cirujeda, A., J. Aibar, M. M. Moreno, and C. Zaragoza. "Effective mechanical weed control in processing tomato: Seven years of results." Renewable Agriculture and Food Systems 30, no. 3 (November 14, 2013): 223–32. http://dx.doi.org/10.1017/s1742170513000434.
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AbstractOpen-air crops are important in Spanish horticulture. The limited number of herbicide active ingredients in minor crops, the waste problem of polyethylene (PE) plastic mulch and the high prices of biodegradable plastics leave hand-weeding and mechanical weed control as the most viable weed control methods. Different tools have been tested in northern European countries but their performance remains unknown in the edaphoclimatic situation of southern Europe. The objective of this work was to test novel physical weed control methods on processing tomato in northeastern Spain compared with other effective control methods, i.e., plastic and paper mulches. A first sequence of field trials was established from 2005 to 2008 at Zaragoza (Spain) to select the best physical control methods out of flamer, torsion weeder, finger weeder, flex-tine harrow and brush hoe used alone or in combination. The best method was the brush hoe which was then compared from 2009 to 2011 with PE mulch, biodegradable plastic mulch and paper mulch. Flamer, flex-tine harrow, torsion weeder and finger weeder performed quite irregularly due to crusty soil conditions and needed additional tools or repeated treatments to increase weed control efficacy. The brush hoe performed best in this soil situation working at about 5 cm depth. Weed biomass reduction was higher than 80% in 6 out of 7 years and similar yield was obtained in the brushed plots compared to the yield obtained with PE, biodegradable plastic and paper mulch. The brush hoe is thus a suitable option for weed control in processing tomato while the other tools were too weak to control aggressive summer weeds in the tested conditions.
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Fernández-Sanz, Ana M., M. Rosario Rodicio, and Ana J. González. "Phenotypic and genotypic analysis of Pseudomonas syringae recovered from symptomatic beans and associated weeds in Northern Spain." European Journal of Plant Pathology 157, no. 2 (May 15, 2020): 377–87. http://dx.doi.org/10.1007/s10658-020-02010-z.
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Santín-Montanyá, M. I., and A. Sombrero Sacristán. "The effects of soil tillage techniques on weed flora in high input barley systems in northern Spain." Canadian Journal of Plant Science 100, no. 3 (June 1, 2020): 245–52. http://dx.doi.org/10.1139/cjps-2019-0178.
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In barley cropping systems of northern Spain, agronomic practices and weather conditions are key components of weed control efficacy. We compared the short-term effects of conventional tillage with minimum tillage (MT) and zero tillage (ZT), in barley monoculture and barley rotation systems. Weed density and weed species number were measured at tillering and flowering barley stages. We found that tillage system can influence weed density and weed species establishment due to, in part, the available light for weed seeds. The results obtained indicate that the MT system facilitates the prevalence of the grass weed Bromus diandrus Roth (50.37%) and the annual dicots Galium aparine (L.) and Buglossoides arvensis (L.) I.M. Johnst. abundant were high in the MT system too, 43.71% and 43.97% respectively. The germination of these species showed a high dependence on light availability. We saw that barley-monoculture plots had a large infestation of Bromus (71.29%) and barley-rotated plots presented more infestation of Galium and Buglossoides (74.36% and 84.4%, respectively). After herbicide application, weed infestation in conservation systems was reduced in barley-rotated plots compared with barley-monoculture. If conservation systems avoided the presence of dominant weeds, the weight of each weed species was balanced within competitive relationships of the cropping systems. Our results confirmed that MT and ZT systems favour different weed species emergences in barley-rotated plots. The combination of MT and barley-rotated cropping system resulted in greater weed diversity and lower total weed density.
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Loureiro, Iñigo, Inés Santin-Montanyá, María-Concepción Escorial, Esteban García-Ruiz, Guillermo Cobos, Ismael Sánchez-Ramos, Susana Pascual, Manuel González-Núñez, and María-Cristina Chueca. "Glyphosate as a Tool for the Incorporation of New Herbicide Options in Integrated Weed Management in Maize: A Weed Dynamics Evaluation." Agronomy 9, no. 12 (December 11, 2019): 876. http://dx.doi.org/10.3390/agronomy9120876.
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A farm-scale investigation was conducted to evaluate the potential impact of integrating glyphosate into different weed management programs when cultivating herbicide-tolerant maize in central Spain from 2012 to 2014. The weed management programs were (1) a conventional weed management with pre- and post-emergent herbicide applications, (2) a weed management program in which the number and total amount of conventional herbicides applied were reduced, and (3) three weed management programs that comprised either two post-emergent applications of the herbicide glyphosate, or only one glyphosate application combined with pre- and/or post-emergent herbicides. Weed density throughout each cropping season was greater in those weed management programs that did not include a pre-emergence application of herbicides than those that did. Moreover, none of the weed management programs affected the richness and species diversity of the weeds or reduced yields. Although the impact of the different programs was similar in terms of weed species diversity, the composition of the weed community differed and this effect must be considered when providing agroecosystem services. Our results indicate that glyphosate-tolerant maize provides an additional tool that allows integrated weed control of the weed populations without reducing yields.
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Mansilla Martínez, José, José-Arturo de Juan Valero, Alfonso Domínguez Padilla, and María-Raquel Picornell Buendía. "Competition and critical periods in spring sugar beet cultivation." Journal of Plant Protection Research 55, no. 4 (December 1, 2015): 336–42. http://dx.doi.org/10.1515/jppr-2015-0044.
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AbstractHigh yields with low costs require that sugar beets be kept free of weeds, during critical periods, using labor or chemical treatments. Since the critical periods for this crop in Castilla - La Mancha (Spain) are unknown, the first goal of this study was to determine the effect of early and late competition on yield. The second goal was to determine the critical periods, while taking into consideration the semiarid climatic conditions of this region. Two irrigation farms located in the province of Albacete are dedicated to sugar beet cultivation. These two farms were chosen to carry out the tests March (140,000-150,000 seeds ∙ ha-1) and harvested in October. Two simultaneous and complementary experiments were carried out in each year and farm. Two scenarios were considered with eight different treatments each. In the first one (With Weeds Until - WWU), plots were infested by weeds up to a certain date. In the second one (Free of Weeds Until - FWU), plots were kept free of weeds up to a certain date. For each test, a randomised experimental blocked field was designed and there were four repetitions, each of them containing eight elemental plots (12 m2). Each plot was weeded by hand or weeds were left to grow till a definite date.The results indicated that a 1% loss of yield was reached in the early competition after 14 days, while a loss of 5% was reached after a period of 41 days after it was infested. The results also indicated that in late competition, if a crop is kept clean for 124 days and it is infested afterwards, a 1% loss is reached. However, the loss increases to 5% if the plot is kept clean for 111 days. For a 1% loss the critical period is 110 days and 70 days for a 5% loss.
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Izquierdo, Jordi, Alice E. Milne, Jordi Recasens, Aritz Royo-Esnal, Joel Torra, Richard Webster, and Bárbara Baraibar. "Spatial and Temporal Stability of Weed Patches in Cereal Fields under Direct Drilling and Harrow Tillage." Agronomy 10, no. 4 (March 25, 2020): 452. http://dx.doi.org/10.3390/agronomy10040452.
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The adoption of conservation agriculture (CA) techniques by farmers is changing the dynamics of weed communities in cereal fields and so potentially their spatial distribution. These changes can challenge the use of site-specific weed control, which is based on the accurate location of weed patches for spraying. We studied the effect of two types of CA (direct drilling and harrow-tilled to 20 cm) on weed patches in a three-year survey in four direct-drilled and three harrow-tilled commercial fields in Catalonia (North-eastern Spain). The area of the ground covered by weeds (hereafter called “weed cover”) was estimated at 96 to 122 points measured in each year in each field, in 50 cm × 50 cm quadrats placed in a 10 m × 10 m grid in spring. Bromus diandrus, Lolium rigidum, and Papaver rhoeas were the main weed species. The weed cover and degree of aggregation for all species varied both between and within fields, regardless of the kind of tillage. Under both forms of soil management all three were aggregated in elongated patterns in the direction of traffic. Bromus was generally more aggregated than Lolium, and both were more aggregated than Papaver. Patches were stable over time for only two harrow-tilled fields with Lolium and one direct-drilled field with Bromus, but not in the other fields. Spatial stability of the weeds was more pronounced in the direction of traffic. Herbicide applications, crop rotation, and traffic seem to affect weed populations strongly within fields, regardless of the soil management. We conclude that site-specific herbicides can be applied to control these species because they are aggregated, although the patches would have to be identified afresh in each season.
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Curt, M. D., P. V. Mauri, M. Sanz, J. Cano-Ruiz, J. P. del Monte, P. L. Aguado, and J. Sánchez. "The ability of the Arundo donax crop to compete with weeds in central Spain over two growing cycles." Industrial Crops and Products 108 (December 2017): 86–94. http://dx.doi.org/10.1016/j.indcrop.2017.06.015.
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Cavero, Jose, Carlos Zaragoza, and Ramiro Gil-Ortega. "Tolerance of Direct-seeded Pepper (Capsicum annuum) Under Plastic Mulch to Herbicides." Weed Technology 10, no. 4 (December 1996): 900–906. http://dx.doi.org/10.1017/s0890037x00040999.
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Tolerance of direct-seeded pepper under clear plastic mulch to herbicides applied pre- and post-emergence was investigated in 1991 and 1992. Weed control of herbicides applied preemergence was also studied. Paprika cultivar ‘Buketen’ and canning cultivars ‘Piquillo de Lodosa’ and ‘Pico de Mendavia’ were seeded in the field in Zaragoza, Spain, in a loamy soil. Percent emergence, plant mortality after the postemergence treatment, dry weight of plants, and fruit weight were recorded. Pepper was tolerant to diphenamid and napropamide applied preemergence but these herbicides did not control broadleaf weeds. Clomazone, when applied preemergence resulted in chlorotic seedlings and at 2 kg ai/ha reduced the final stand, but was selective when applied at the 6 to 8-leaf stage of the crop. Pepper was tolerant to diethatyl-ethyl when applied preemergence. However, diethatyl-ethyl applied postemergence caused severe phytotoxicity symptoms, and when mixed with diphenamid, fruit ripeness in 1992 was delayed. Weed control during the crop emergence period was better when diethatyl-ethyl was used mixed with diphenamid or napropamide.
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Sánchez-Campos, S., J. Navas-Castillo, R. Camero, C. Soria, J. A. Díaz, and E. Moriones. "Displacement of Tomato Yellow Leaf Curl Virus (TYLCV)-Sr by TYLCV-Is in Tomato Epidemics in Spain." Phytopathology® 89, no. 11 (November 1999): 1038–43. http://dx.doi.org/10.1094/phyto.1999.89.11.1038.
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A progressive displacement of tomato yellow leaf curl virus (TYLCV)-Sr by TYLCV-Is was observed in tomato epidemics in southern Spain based on incidence data of both virus species obtained during surveys conducted between 1996 and 1998. Ecological factors that might be involved in such a displacement, such as competition of TYLCV-Sr and TYLCV-Is in tomato, transmission by local biotypes (B and Q) of Bemisia tabaci, and presence in weeds and alternate crops, have been analyzed. No selective advantage is observed for TYLCV-Sr or TYLCV-Is in tomato plants either infected via Agrobacterium tumefaciens or via B. tabaci. However, TYLCV-Is is more efficiently vectored by local biotypes of B. tabaci; and common bean, a bridge crop between tomato crops, is a host for TYLCV-Is but not TYLCV-Sr. Therefore, common bean acts as a reservoir for TYLCV-Is. These two factors are probably responsible for the displacement of TYLCV-Sr by TYLCV-Is as the causative agent of epidemics in tomato in southern Spain.
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Sousa-Ortega, Carlos, José Luis Fernandez, and Mino Sportelli. "Case Report of Avena sterilis subsp. sterilis ACCase Herbicide Resistance in Southern Spain." Agriculture 13, no. 1 (December 28, 2022): 85. http://dx.doi.org/10.3390/agriculture13010085.
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Wild oats are worldwide grassy weeds that cause substantial yield losses, particularly in winter cereal crops. In addition, wild oat herbicide resistant cases have increased; indeed, up to 52 cases have been registered. Despite this, no wild oat herbicide resistant cases have been described in Spain, where farmers and technicians have reported poor herbicide efficacy in sterile oats (Avena sterilis subsp. sterilis L.). A dose-response experiment was conducted comparing the behavior of two populations of A. sterilis from southern Spain to a susceptible population. These populations were collected from two commercial farms where a low efficacy of chemical control had been described. Clodinafop-propargyl and Pinoxaden were tested as active ingredients in the dose-response experiment. Additionally, an alternative herbicide, which consisted of a mixture of Mesosulfuron-methyl and Propoxycarbazone-Na, was also tested at a field dose. The two populations of A. sterilis studied provided a resistant factor higher than 10 for Clodinafop-propargyl and higher than 4 for Pinoxaden. A total control was achieved for plants treated with Mesosulfuron-methyl and Propoxycarbazone-Na.
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Escorial, María-Concepción, María-Cristina Chueca, Andrés Pérez-Fernández, and Iñigo Loureiro. "Glyphosate sensitivity of selected weed species commonly found in maize fields." Weed Science 67, no. 6 (October 1, 2019): 633–41. http://dx.doi.org/10.1017/wsc.2019.54.
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AbstractGlyphosate resistance has evolved worldwide. Glyphosate is also the most used herbicide in Spain, and current changes in herbicide usage patterns can increase the risk of glyphosate resistance development. The objective of this study was to assess the glyphosate sensitivity of different selected weed species important in Spanish maize (Zea mays L.) fields. To this end, dose–response experiments were conducted under controlled conditions in a growth chamber to examine variation in glyphosate sensitivity among populations of five grass weed species and eight broadleaf weed species that are commonly found in the maize fields in Castilla y León, the biggest maize-growing region in Spain. The glyphosate doses that caused growth reduction by 50% (GR50) were calculated for each weed population. No populations were resistant to glyphosate. In addition, baseline values of glyphosate sensitivity were determined for each weed species. The GR50 baseline values ranged from 10.25 to 53.23 g ai ha−1 for the dicotyledonous weed species and from 16.05 to 66.34 g ai ha−1 for the monocotyledonous weed species. The ratio between the GR50 values of the least and most sensitive populations was used to determine the SI50 (sensitivity index at 50% growth reduction) for each weed species. The SI50 values showed a 1.4- to 3.3-fold difference in sensitivity for dicotyledonous weed species and 1.4- to 2.4-fold difference for monocotyledonous weed species. The sensitivity index was also calculated as the ratio between the GR50 values of the least sensitive population and the baseline GR50 value estimated for a range of susceptible populations (SI50b). SI50b values showed a 1.2- to 1.6-fold difference in sensitivity for dicotyledonous weed species and 1.1- to 1.2-fold difference for monocotyledonous weed species. The sensitivity data generated in this study provide a reference for determining time-dependent changes in glyphosate sensitivity in the commonly found weeds in the maize fields of Castilla y Léon.
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Gómez de Barreda, Diego, Inmaculada Bautista, Vicente Castell, and Antonio Lidón. "Rice Straw Mulch Installation in a Vineyard Improves Weed Control and Modifies Soil Characteristics." Agronomy 13, no. 12 (December 15, 2023): 3068. http://dx.doi.org/10.3390/agronomy13123068.
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After harvesting rice paddy fields, rice straw is a significant problem due to uncontrolled CO2 emissions when the straw is burned. One solution to this problem is to use this rice by-product for mulching planting lines of fruit trees or vineyards with the purpose of controlling weeds and improving soil characteristics. A 3-year experiment was conducted at the Polytechnic University of Valencia (Spain) demonstration vineyard, where rice-straw mulch was installed at three rates in 2021, 24.0, 43.1, and 63.1 t ha−1, and in 2022, 25.0, 37.5, and 50.0 t ha−1. Weeds were mainly controlled with the highest treatment rate (50.0–63.1 t ha−1), as the time of the year for mulch installation is decisive for achieving different weed control rates. On average, mulch decreased soil bulk density (5.4%), and increased the soil organic carbon (24.3%) and water-soluble organic carbon (24.3%) compared to bare soil. Soil temperature changes were observed due to the mulch treatment, with soil temperature lower in bare soil than in mulched soil during the cold season, and higher during the warm season. This effect was highly dependent on the mulch application rate. Soil moisture content was also higher under the mulch treatment, showing a mulch-rate response during the four seasons of the year. The changes in the physical and biological soil properties induced a higher soil respiration rate when mulched soil was compared to bare soil. This study concludes that the use of rice straw as a mulch had positive effects on weed control and soil properties, although three factors concerning mulch management were paramount: rate, the timing of installation, and replacement rate.
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Lopez, S., M. D. Carro, J. S. Gonzalez, and F. J. Ovejero. "Rumen degradation of the main forage species harvested from permanent mountain meadows in North-western Spain." Journal of Agricultural Science 117, no. 3 (December 1991): 363–69. http://dx.doi.org/10.1017/s0021859600067113.
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SUMMARYHerbage samples were collected in late June, and again in early September (1987) from permanent mountain meadows situated in North-western Spain (León). Botanical composition was determined by grouping the species into grasses, legumes and herbaceous ‘weeds’. Rumen degradability of the dry matter (DM), crude protein (CP) and neutral detergent fibre (NDF) of the botanical groups in each harvest season was determined by the nylon-bag technique.Grasses and legumes differed in their degradation characteristics, and the comparisons between forage species were different for the two harvest seasons. There were no significant differences between September grasses, June legumes and September legumes in the potential degradabilities of the DM (86·9, 87·1 and 88·4%) and CP (94·2, 92·4 and 93·8%). The NDF of grasses harvested in September was degraded to a greater extent (80·6%) than that of legumes from both harvests (70·9 and 73·6% in June and September respectively). However, June grasses showed significantly lower potential degradabilities for the DM (77·0 %), CP (84·3%) and cell wall (65·9%). Legumes were degraded at a faster rate than grasses (mean DM degradation rates of 0·143 and 0·057 respectively), and lag times were longer for grasses (4·7 h) than for legumes (2·5 h). Rumen degradation characteristics of the herbaceous ‘weeds’ were estimated, but it should be remembered that many other factors may limit their utilization by ruminants.It was concluded that the major constraint to the nutritive value of these permanent swards would be the maturity of the grasses harvested in June, which markedly reduced the rumen degradability of the forages.
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Torra, Joel, José M. Montull, Isabel M. Calha, María D. Osuna, Joao Portugal, and Rafael de Prado. "Current Status of Herbicide Resistance in the Iberian Peninsula: Future Trends and Challenges." Agronomy 12, no. 4 (April 13, 2022): 929. http://dx.doi.org/10.3390/agronomy12040929.
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The evolution of herbicide resistance in weeds has emerged as one of the most serious threats to sustainable food production systems, which necessitates the evaluation of herbicides to determine their efficacy. The first herbicide resistance case in the Iberian Peninsula was reported about 50 years ago, wherein Panicum dichotomiflorum was found to be resistant (R) to atrazine in Spanish maize fields. Since then, herbicide resistance has evolved in 33 weed species, representing a total of 77 single-herbicide-resistance cases in this geographic area: 66 in Spain and 11 in Portugal. Changes in agricultural practices, namely the adoption of non-tillage systems and the increased use of herbicides, led to the selection of weed biotypes resistant to a wide range of herbicides. Nowadays the most important crops in Spain and Portugal (maize, winter cereals, rice, citrus, fruits, and olive orchards) are affected, with biotypes resistant to several mechanisms of action (MoAs), namely: ALS inhibitors (20 species), ACCase inhibitors (8 species), PS II inhibitors (18 species), and synthetic auxin herbicides (3 species). More recently, the fast increase in cases of resistance to the EPSPS-inhibiting herbicide glyphosate has been remarkable, with 11 species already having evolved resistance in the last 10 years in the Iberian Peninsula. The diversity of resistance mechanisms, both target-site and non-target-site, are responsible for the resistance to different MoAs, involving point mutations in the target site and enhanced rates of herbicide detoxification, respectively. More serious are the 13 cases reported with multiple-herbicide resistance, with three cases of resistance to three–four MoAs, and one case of resistance to five MoAs. Future research perspectives should further study the relationship between management strategies and the occurrence of TSR and NTSR resistance, to improve their design, develop monitoring and diagnostic tools for herbicide resistance, and deepen the study of NTSR resistance.
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Osca, José M., Felip Galán, and Héctor Moreno-Ramón. "Rice Paddy Soil Seedbanks Composition in a Mediterranean Wetland and the Influence of Winter Flooding." Agronomy 11, no. 6 (June 12, 2021): 1199. http://dx.doi.org/10.3390/agronomy11061199.
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Soil seedbanks are defined in composition and quantity by many environmental factors inherent to a specific area, and they can be an indicator of the potential problems of weeds in crops. In Valencia (Spain), rice is cultivated with continuous flooding during the growing season, and after harvesting, many of the paddy fields are flooded again during the winter. This study investigates the paddy fields’ soil seedbank composition in this Mediterranean paddy area and the effect of winter flooding on the soil seedbank. Multispectral images from the Sentinel-2 satellite were used to characterise the water level of paddies in winter. Satellite images facilitated the characterisation of winter flooding in fields. Soil samples from sixty-nine points distributed over 15,000 ha of paddies were used to determine the composition of the seedbank plots. The data were spatially represented by geographic information systems. The species that contributed most to the paddy seedbank were Cyperus difformis L., an important rice weed in the Mediterranean area, and other rice weeds such as Echinochloa sp. and Leptochloa fusca subspecies. Other species with a great contribution to the seedbank are species that develop in paddy fields that produce a large quantity of small seeds, such as Lemna sp., Polypogon monspeliensis (L.) Desf., and Nasturtium officinale R. Br. These species interfere little or do not interfere with the rice crop. The study revealed that in general, flooding reduced seedbank density with differences between species. Furthermore, the influence of winter flooding on the different plant species obtained as well as their distribution maps are a further step in this protected area from the point of view of weed management in rice crop, as well as in the management of this Mediterranean wetland.
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LAVINA, A., J. ARAMBURU, and E. MORIONES. "Occurrence of tomato spotted wilt and cucumber mosaic viruses in field-grown tomato crops and associated weeds in northeastern Spain." Plant Pathology 45, no. 5 (October 1996): 837–42. http://dx.doi.org/10.1111/j.1365-3059.1996.tb02893.x.
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Abad, Javier, Marín Diana, Santesteban L. Gonzaga, Cibriáin José Félix, and Sagüés Ana. "Under-vine cover crops: impact on weed development, yield and grape composition." OENO One 54, no. 4 (November 4, 2020): 975–83. http://dx.doi.org/10.20870/oeno-one.2020.54.4.4149.
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This study aims to evaluate the interest of using an under-vine cover crop as a sustainable management tool replacing herbicides or tillage to control weeds, evaluating its effects on yield and berry parameters in a semi-arid climate. The performance of Trifolium fragiferum as an under-vine cover crop was evaluated in 2018 and 2019 in a Merlot vineyard in Traibuenas (Navarra, Spain). This trial showed that the soil under the vines was covered by 80 % of the cover crop in August 2018 and 100 % in Aug 2019, with clover (T. fragiferum) comprising around 26 % and 70 % of the cover crop surface, respectively. The presence of the cover crop only reduced the number of shoots in the second year, although both years there was an increment in water stress. Neither yield, cluster weight nor berry weight were affected by the presence of the under-vine cover crop. Similarly, no changes in grape composition were observed. The use of T. fragiferum-like cover crops under the vine allows for better control of weeds, provided a good installation is achieved. In the first two years, this cover crop reduced vegetative growth and increased water deficit slightly. However, no changes in yield and grape composition were observed.In a context of herbicide suppression and search for sustainable management, under-vine clover cover crops constitute a viable alternative in semi-arid regions provided drip irrigation can be applied.
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Anzalone, A., A. Cirujeda, J. Aibar, G. Pardo, and C. Zaragoza. "Effect of Biodegradable Mulch Materials on Weed Control in Processing Tomatoes." Weed Technology 24, no. 3 (September 2010): 369–77. http://dx.doi.org/10.1614/wt-09-020.1.
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Three years of field trials have been carried out in Zaragoza, Spain, using different biodegradable mulch materials in processing tomatoes. The aim was to evaluate weed control with several biodegradable mulches as alternatives to black polyethylene (PE) mulch. The treatments were rice straw, barley straw, maize harvest residue, absinth wormwood plants, black biodegradable plastic, brown kraft paper, PE, herbicide, manual weeding, and unweeded control. Assessments focused on weeds and on crop yield. A laboratory study showed that 1 kg/m2of organic mulch was sufficient to cover the soil for rice, barley straw, and maize harvest residue. The most abundant weed species in the field were purple nutsedge, common purslane, common lambsquarters, and large crabgrass and a change in weed composition was observed between treatments and years. Most weed species were controlled by the mulching materials except that purple nutsedge was controlled only by paper mulch. The other species were well controlled by PE and biodegradable plastic and also by some of the organic mulch treatments. Best weed control and lowest weed biomass were achieved by paper followed by PE and biodegradable plastic. The best organic mulch was rice straw and the worst weed control was from absinth wormwood. Tomato yield was highest for PE followed by paper, manual weeding, biodegradable plastic, and rice straw and was clearly related to weed control. Paper, biodegradable plastic, and rice straw are potential substitutes for PE and herbicides.
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Pardo, Gabriel, Ana Isabel Marí, Joaquín Aibar, and Alicia Cirujeda. "Do Crop Rotations in Rice Reduce Weed and Echinochloa spp. Infestations? Recommendations for Integrated Weed Control." Agronomy 11, no. 3 (February 28, 2021): 454. http://dx.doi.org/10.3390/agronomy11030454.
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The species belonging to the genus Echinochloa represent the main weeds in rice fields worldwide. Heavy soils are especially appropriate for this crop that is often grown in monoculture. A drought period in 2012 impeded farmers from sowing rice in some parts of the region of Aragon (northeastern Spain) and, unusually, they seeded alternative crops such as winter cereal, fescue (Festuca arundinacea), ryegrass (Lolium multiflorum) and lucerne (Medicago sativa). A total of 20 fields were selected, in which rice had been grown in monocrop until 2011 and several crop sequences were established afterwards; weed vegetation was recorded in spring, summer and autumn 2014-16 to find out if the crop rotations reduced weed infestations. Winter cereal and fescue were the crops with the highest soil cover; ryegrass and lucerne had difficulties in installation probably due to the heavy soil textures. Echinochloa spp. plants were found in the winter cereal stubble after having grown fescue for the previous two years and rice before that; in the forage fields, small plants of earing Echinochloa spp. adapted to mowing were detected. Recommendations for Integrated Weed Management that arise from the observations are ploughing the winter cereal stubble before seed shed of the emerged Echinochloa plants, assuring a high density of the forage crops, and efficient herbicide control in rice fields.
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Webster, C. G., C. S. Kousik, P. D. Roberts, E. N. Rosskopf, W. W. Turechek, and S. Adkins. "Cucurbit yellow stunting disorder virus Detected in Pigweed in Florida." Plant Disease 95, no. 3 (March 2011): 360. http://dx.doi.org/10.1094/pdis-11-10-0813.
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Pigweeds (genus Amaranthus) are problematic weeds in crop production throughout the world and are responsible for significant yield losses in many crops (2). Members of this genus can produce hundreds of thousands of seeds per plant and are also capable of supporting populations of important crop pathogens including viruses, nematodes, fungi, and oomycetes. Thirty-one pigweed samples (tentatively identified as Amaranthus lividus L. based on leaf notch and growth habit) were collected in November and December of 2009 from a watermelon field near Immokalee, FL, previously found to contain watermelon plants infected with three whitefly-transmitted viruses: Cucurbit yellow stunting disorder virus (CYSDV), Cucurbit leaf crumple virus (CuLCrV), and Squash vein yellowing virus (SqVYV). Although no obvious virus symptoms were observed on any of the pigweed plants, whiteflies (Bemisia tabaci), a known vector of CYSDV, CuLCrV, and SqVYV, were observed on leaves. Consequently, replica tissue blots were made from all pigweed samples and tested independently by tissue blot nucleic acid hybridization assay for CYSDV, CuLCrV, or SqVYV (3). Tissue blots indicated CYSDV infection in six pigweed samples. Neither CuLCrV nor SqVYV was detected. Three of the tissue blot-positive pigweed samples were further tested by reverse transcription (RT)-PCR amplification from total RNA (extracted from leaf tissue with TRIzol Reagent [Invitrogen, Carlsbad, CA]) with HSP70 and coat protein (CP) gene primers (1). HSP70 and CP gene RT-PCR products of the expected sizes (175 and 707 nt, respectively) were amplified, sequenced, and found to be 100% identical for all three pigweed samples. The partial HSP70 gene sequence from pigweed shared 98.3 to 100% nucleotide identity with CYSDV isolates from Arizona, California, and Spain (GenBank Accession Nos. FJ492808, EU596530, and NC_004810, respectively). The partial CP gene sequence from pigweed shared 88.8 to 100% nucleotide identity with CYSDV isolates from Arizona, Saudi Arabia, Texas, and Spain (GenBank Accession Nos. EF210558, AF312811, AF312806, and AF312808, respectively). To our knowledge, this is the first report of CYSDV infection of pigweed in Florida. Infection of redroot pigweed (A. retroflexus) was recently reported in California (4). These results collectively indicate that control of noncucurbit weeds may be important for effective management of CYSDV in cucurbit crops. References: (1) S. Adkins et al. Online publication. doi:10.1094/PHP-2009-1118-01-BR. Plant Health Progress, 2009. (2) L. Holm et al. World's Weeds: Natural Histories and Distributions. John Wiley and Sons, Inc. New York, NY, 1997. (3) W. W. Turechek et al. Phytopathology 100:1194, 2010. (4) W. M. Wintermantel et al. Plant Dis. 93:685, 2009.
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Jurado-Expósito, Montserrat, Francisca López-Granados, Francisco Manuel Jiménez-Brenes, and Jorge Torres-Sánchez. "Monitoring the Spatial Variability of Knapweed (Centaurea diluta Aiton) in Wheat Crops Using Geostatistics and UAV Imagery: Probability Maps for Risk Assessment in Site-Specific Control." Agronomy 11, no. 5 (April 29, 2021): 880. http://dx.doi.org/10.3390/agronomy11050880.
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Assessing the spatial distribution of weeds within a field is a key step to the success of site-specific weed management strategies. Centaurea diluta (knapweed) is an emerging weed that is causing a major agronomic problem in southern and central Spain because of its large size, the difficulty of controlling it, and its high competitive ability. The main objectives of this study were to examine the spatial variability of C. diluta density in two wheat fields by multivariate geostatistical methods using unmanned aerial vehicle (UAV) imagery as secondary information and to delineate potential control zones for site-specific treatments based on occurrence probability maps of weed infestation. The primary variable was obtained by grid weed density field samplings, and the secondary variables were derived from UAV imagery acquired the same day as the weed field surveys. Kriging and cokriging with UAV-derived variables that displayed a strong correlation with weed density were used to compare C. diluta density mapping performance. The accuracy of the predictions was assessed by cross-validation. Cokriging with UAV-derived secondary variables generated more accurate weed density maps with a lower RMSE compare with kriging and cokriging with RVI, NDVI, ExR, and ExR(2) (the best methods for the prediction of knapweed density). Cokriged estimates were used to generate probability maps for risk assessment when implementing site-specific weed control by indicator kriging. This multivariate geostatistical approach enabled the delineation of winter wheat fields into two zones for different prescription treatments according to the C. diluta density and the economic threshold.
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Le Corre, Valérie, Mathieu Siol, Yves Vigouroux, Maud I. Tenaillon, and Christophe Délye. "Adaptive introgression from maize has facilitated the establishment of teosinte as a noxious weed in Europe." Proceedings of the National Academy of Sciences 117, no. 41 (September 28, 2020): 25618–27. http://dx.doi.org/10.1073/pnas.2006633117.
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Global trade has considerably accelerated biological invasions. The annual tropical teosintes, the closest wild relatives of maize, were recently reported as new agricultural weeds in two European countries, Spain and France. Their prompt settlement under climatic conditions differing drastically from that of their native range indicates rapid genetic evolution. We performed a phenotypic comparison of French and Mexican teosintes under European conditions and showed that only the former could complete their life cycle during maize cropping season. To test the hypothesis that crop-to-wild introgression triggered such rapid adaptation, we used single nucleotide polymorphisms to characterize patterns of genetic variation in French, Spanish, and Mexican teosintes as well as in maize germplasm. We showed that both Spanish and French teosintes originated fromZea maysssp.mexicanarace “Chalco,” a weedy teosinte from the Mexican highlands. However, introduced teosintes differed markedly from their Mexican source by elevated levels of genetic introgression from the high latitude Dent maize grown in Europe. We identified a clear signature of divergent selection in a region of chromosome 8 introgressed from maize and encompassingZCN8, a major flowering time gene associated with adaptation to high latitudes. Moreover, herbicide assays and sequencing revealed that French teosintes have acquired herbicide resistance via the introgression of a mutant herbicide-target gene (ACC1) present in herbicide-resistant maize cultivars. Altogether, our results demonstrate that adaptive crop-to-wild introgression has triggered both rapid adaptation to a new climatic niche and acquisition of herbicide resistance, thereby fostering the establishment of an emerging noxious weed.
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Cerdà, Artemi, Jesús Rodrigo-Comino, Antonio Giménez-Morera, and Saskia D. Keesstra. "Hydrological and erosional impact and farmer’s perception on catch crops and weeds in citrus organic farming in Canyoles river watershed, Eastern Spain." Agriculture, Ecosystems & Environment 258 (April 2018): 49–58. http://dx.doi.org/10.1016/j.agee.2018.02.015.
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