bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interaction between diclofop‐methyl and 2,4‐D in wild oat (Avena fatua L.) and cultivated oat (Avena sativa L.), and fate of diclofop‐methyl in cultivated oat
Authors: KAFIZ B. , CAUSSANEL J. P. , SCALLA R. , GAILLARDON P. 
Published: July 2006

SummaryInfluence of 2,4‐D on toxicity of diclofop‐methyl to Avena sativa (cv. Selma) and Arena fatua at 2·5 leaf stage has been evaluated under controlled conditions. Effects of 2,4‐D on the fate of diclofop‐methyl in cultivated oat have also been studied. Mixture with 2,4‐D reduced the toxicity of diclofop‐methyl to both species. When applied immediately after diclofop‐methyl treatment, 2,4‐D still reduced herbicide toxicity to wild oat. This reduction was smaller in cultivated oat. and was only observed at higher phytotoxicity. No interaction was observed when a 10‐day period separated the two applications. In mixture, 2,4‐D enhanced diclofop‐methyl penetration and diclofop acid conjugation in cultivated oat, and it slightly increased conjugation when applied separately. None of these effects clearly explain the reduction of diclofop‐methyl toxicity by 2, 4‐D in cultivated oat. Other processes are possibly involved and could be connected with the site of action of diclofop‐methyl.
The influence of the herbicide mefenacet on cell division and cell enlargement in plants
Authors: HESS F. D. , HOLMSEN J. D. , FEDTKE C. 
Published: July 2006

Summary:The herbicide mefenacet has recently been developed for pre–emergence control of graminaceous and some dicotyledonous weeds in rice. Whereas mefenacet is known to inhibit root growth, its effect on the components of growth, cell division and cell enlargement, have not been determined. The purpose of this study was to evaluate the influence of mefenacet on growth, cell enlargement and cell division in Chlamydomonas (a green alga) and oats. Cell division in Chlamydomonas was completely inhibited and cell enlargement was inhibited by an average of 18% during the first cell cycle period when cells were treated with 6–7 μM mefenacet. The rate of oat root growth in sand culture between 12 and 24 h after initiation of treatment was reduced 90% at 10 μM mefenacet. Cell enlargement of oat coleoptile sections in culture solution was inhibited 25% at 10 μM. Mefenacet inhibited mitotic entry rather than disrupted the mitotic sequence. Cell division in oat roots was inhibited 54% by 10 μM mefenacet. This shows cell division inhibition occurs in G1, S, or G2 of the cell cycle. The action of mefenacet is most like that of the chloroacetamides among the herbicide classes known to inhibit growth.
The effect of chemical and heat treatments on germination of Commelina benghalensis L. aerial seeds
Authors: KIM S. Y. , DE DATTA S. K. , MERCADO B. L. 
Published: July 2006

Summary:The effects of concentrated sulphuric acid, dry heat, hot water and NaOCl treatments on the germinability of dormant large and small aerial Commelina benghalensis L. seeds were evaluated. Concentrated sulphuric acid and NaOCl treatments were more effective than the dry heat and hot water treatments in breaking the dormancy of C. benghalensis aerial seeds. Treatments increased germination of both seed types due to its effect on the seed coat integrity. A scanning electron microscope revealed that changes as a result of scarification occurred in the hilum region of the seed and in the seed coat surface. The large aerial seeds were affected by all treatments more than the small aerial seeds. Difference in germinability between the two seed types was related to the difference in their seed vigour.
Output and dispersal of propagules of Carduus acanthoides L
Authors: FELDMAN SUSANA R. , LEWIS J. P. 
Published: July 2006

Summary:Propagules of Carduus acanthoides are pappus‐bearing achenes. Flower production, potential achene output, seedbank and wind dispersal of propagules of Carduus acanthoides were analysed. Flower production was measured in four cohorts in 1986–87 and three cohorts the following reproductive season, when the potential achene output was estimated. Achene output was very large in all cases but early cohorts had a longer fruiting period and produced more flowers and fruits per plant. The seedbank was small and results from autumn and spring samples showed a low seed persistence in soil. In laboratory experiments greater landing and dispersion distances were reached at higher wind speeds, the major wind effect being that on the movement of propagules after landing. Barriers simulating vegetation almost completely stopped this movement after landing and the final distances reached were almost the same at all wind speeds. In field experiments achenes recovered in seed traps and seedling emergence show the same pattern of distribution around the parent plant. The implication of these results for the behaviour of thistle populations are discussed.
Growth of Emex australis out‐of‐season: relevance to biological control of an annual weed
Authors: PANETTA F. D. 
Published: July 2006

Summary:Populations of the winter annual Emex australis were established by initiating irrigation at monthly intervals, beginning in mid‐summer. Natural seedling densities varied from 100 m−2 when irrigation was begun during late January to almost 700 m−2 when it began at the end of March. Densities were increased by sowing non‐dormant seeds, but most sown seeds became dormant when introduced before autumn. Plants which emerged after the earliest irrigation grew most rapidly. Those originating from the latest irrigation grew most slowly, in association with vigorous growth of other annual species. Because it minimizes interspecific competition, early commencement of irrigation, coupled with sowings of nondormant seeds is the best method for establishing E. australis during summer. Maintenance of such populations may enhance the persistence of non‐aestivating biological control agents and/or boost their numbers prior to the onset of mass germination. This approach could also prove useful for other winter annuals which are targeted for biological control.
Utilisation de l'isoproturon seul ou en association avec d'autres matières actives, en post‐levée en hiver et au printemps sur blé et orge d'hiver
Authors: BERGER B. , HEITEFUSS R. 
Published: July 2006

Zusammenfassung:In einem zweijährigen Versuch auf zwei Standorten (Sand‐ und Lehmboden) wurde Isoproturon allein und in Kombination mit Dinoseb‐acetat und Bifenox zum Nachauflauf Winter (NA‐W) Termin und zum Nachauflauf Frühjahr (NA‐F) Termin in Wintergerste und Winterweizen eingesetzt. Obwohl nach einer Nachauflauf‐Winter Behandlung die anfänglichen Herbizidbelastungen im Böden höher waren, sind nach unseren Ergebnissen im Vergleich zu einer Nachauflauf‐Frühjahr Behandlung am Ende der Vegetationsperiode keine erhöhten Rückstände von Isoproturon zu erwarten. Die DT‐50‐Werte von Isoproturon in den beiden Versuchsjahren und Böden lagen zwischen 12 und 33 Tagen, die DT‐90‐Werte schwankten im Bereich von 34 bis 68 Tagen. Ein Einfluß der mit Isoproturon kombinierten Wirkstoffe auf dessen Abbau im Boden war nicht festzustellen. Eine bessere Unkrautwirkung der NA‐W‐Behandlung führte besonders bei starker Verunkrautung zu höheren Erträgen.
Untersuchungen der Dynamik einer Unkrautgemeinschaft: III. Der langfristige Einfluß der Bodenbearbeitung auf die Artenzusammensetzung des Samenvorrats
Authors: DESSAINT F. , CHADOEUF R. , BARRALIS G. 
Published: July 2006

Résumé:L'évolution de la composition spécifique du stock semencier a été suivie pendant huit années sur quatre parcelles expérimentales différant par le type de travail du sol (profond ou superficiel) et de désherbage chimique (absent ou sélectif). Nos résultats montrent que la composition spécifique du stock n'est pas modifiée sur les parcelles désherbées et que seuls des change‐merits d'ordre quantitatif interviennent au sein de la communauté: certaines espèces, comme Euphorbia exigua et Anagallis arvensis, augmentent ainsi leurs dominances dans le stock sans accroissement de leurs abondances. A l'opposé, sur les parcelles non désherbées, on observe des modifications qualitatives et quantitatives de la composition spécifique avec l'arrivée d'espèces ‘opportunistes’, comme Thlaspi arvense et Sinapis arvensis, qui augmentent considérablement leurs abondances alors qu'elles étaient pratiquement absentes du stock en début de suivi. Le type de travail du sol nuance un peu ces phénomènes en permettant une meilleure homogénéisation sur la couche arable des apports annuels et du stock existant.
Einfluß der Bestandesdichte und der Konkurrenzdauer von Solanum nigrum L. auf die Tomate bet Direktsaat
Authors: CAUSSANEL J. P. , BRANTHÔME X. , MAILLET J. , CARTERON A. 
Published: July 2006

Résumé:Les effets de la densité et de la période de concurrence de Solanum nigrum L. ont été déterminés dans des cultures de tomate en semis direct, en relation avec les techniques de désherbage utilisées dans le Sud‐Est de la France. Des S. nigrum levant après une application de diquat au stade 2–3 feuilles de la plante cultivée et éclaircies à de faibles densites (entre 0 et 12,8 plantes par m2) au stade 5–6 feuilles de la plante cultivée, ont entraîné des pertes significatives de rendement lorsqu'elles concurrençaient la culture jusqu'à la récolte. Les rendements de tomate ont subi de plus faibles réductions lorsque de telles densités étaient présentes jusqu'au début de la floraison. Les courbes de régression ‘rendement de la culture × densité de la mauvaise herbe’ ont été différentes selon les conditions climatiques de l'année affectant la date de semis et la croissance des plantes; une comparaison entre années a été faite d'après la relation l'rendement de la culture × rapport de biomasses adventice/plante cultivée. Des interactions significatives entre la densite de l'adventice et sa période de concurrence ont été constatées pour quelques variables de rendement (fruits verts) ou composantes du rendement (poids moyen d'un fruit rouge). Dans le cas d'un semis direct tardif et pour de faibles densités de S. nigrum en concurrence avec la culture, deux désherbages au stade 5–6 feuilles et debut floraison ont été suffisants pour empêcher le rendement de diminuer.
Fate of fluroxypyr in soil
Authors: LEHMANN R. G. , MILLER J. R. , LASKOWSKI D. A. 
Published: July 2006

Summary:Batch adsorption Koc values of fluroxypyr‐methylheptyl ester (20000 1kg−1) and fluroxypyr (74 1kg−1) indicate increased mobility after hydrolysis of the ester to fluroxypyr. After 1 to 2 weeks incubation time in four soils, desorption Koc values of fluroxypyr were 100‐200 1kg−1 but increased to 400‐700 1kg−1 after 8 weeks. The increase in desorption Koc was related to incubation time and not to concentration, and it was interpreted as an entrapment of the fluroxypyr within the soil organic matter. Similar increases in desorption Koc with incubation time were noticed for pyridinol and methoxypyridine metabolites of fluroxypyr. Koc values also increased along the metabolic sequence fluroxypyr/pyridinol/methoxypyridine, with maximum Koc values of 3000‐4000 1 kg−1 for the methoxypyridine metabolite. Hence mobility of the fluroxypyr aromatic ring strongly decreases with increased residence time in the soil.
Effects of repeated applications of fluazifop‐butyl, haloxyfop and sethoxydim on Elymus repens in strawberries
Authors: CLAY D. V. , LAWRIE J. , HERTZ L. B. 
Published: July 2006

Summary:Fluazifop‐butyl, haloxyfop and sethoxydim with adjuvant oil were applied for three successive growing seasons to established strawberries infested with Elymus repens. The weed was virtually eradicated by three applications of haloxyfop (0.8 kg a.e. ha−1) in successive years. A similar effect was given by five applications of haloxyfop (0.4 kg a.e. ha−1) and fluazifop‐butyl (1.6 kg AI ha−1) in three growing seasons. Lower rates of haloxyfop and fluazifop‐butyl, and a high rate of sethoxydim (1.6 kg AI ha−1) applied five times were less effective, the ground cover of E. repens shoots not being reduced by the end of the experiment although weight of living rhizome was only 10‐30% of that on untreated plots.Fruit yields on treated plots generally reflected the level of E. repens control, but there was some evidence of crop phytotoxicity from herbicide treatments. During the experiment E. repens untreated plots increased from about 30‐100% ground cover and reduced yield 13, 28 and 68% in successive years compared with weed‐free plots.
Weed control in squash and tomato fields by soil solarization in the Jordan Valley
Authors: ABU‐IRMAILEH B. E. 
Published: July 2006

Summary:Black (BPE) and clear polyethylene mulches (CPE), 0.08 and 0.06 mm thick, respectively, were compared for their effectiveness for soil solarization over three seasons during 1986–1989 in weedy fields. Solarization for 6 weeks reduced weed growth and enhanced crop yields. However, further mulching with BPE after solarization with either BPE or CPE gave the best results. Not all weeds were sensitive to solarization. Some weed species were completely controlled; others were reduced to varying degrees; yet other weed species seemed to be enhanced by solarization. Solarization without further mulching was no better than farmer‐practice in reducing weed growth or in increasing crop yield. Weeds required further removal after the middle of the growing season. Any soil disturbance after solarization reduced the weed control effect of solarization. Crops grew best in plots after solarization with BPE if they were planted in the same mulch after it was perforated.
Using plant population biology in weed research: a strategy to improve weed management
Authors: NAVAS M.‐L. 
Published: July 2006

Summary:The aim of this paper is to show the need for developing plant population biology studies in order to improve weed management when traditional approaches in weed science have failed, as shown by recent reviews on herbicide resistance. It is also suggested that the usual weed definitions do not reflect the new aims of weed ecology. The results of studies on the genetic, demographic and spatial variability of weed populations and their regulation by pests and pathogens are reported, and are discussed in the specific case of clonal perennial species.
Effects of tillage, application time and rate on metribuzin dissipation
Authors: SORENSON B. A. , SHEA P. J. , ROETH F. W. 
Published: July 2006

Summary:Metribuzin efficacy and dissipation were determined in two silty clay loam soils following preplant (PP), pre‐emergence (PRE) and split (PP+PRE) application to tilled and no‐till soybeans in rotation with corn at Clay Center and Lincoln, Nebraska. A similar experiment was conducted in tilled and no‐till soybeans in rotation with wheat at Lincoln. Corn and wheat residue in no‐till plots reduced the amount of metribuzin that reached the soil by approximately 54 and 89%, respectively. No differences in weed control or soybean yield were observed between tillage treatments or time of metribuzin application in the corn‐soybean rotation. However, both weed control and yield were reduced in the wheat‐soybean rotation. Most of the metribuzin remained at the 0–5 cm depth, and dissipation was exponential. The mean metribuzin half‐life at the 0–5 cm depth across locations, tillage treatments, application time and rates was 11 days. The metribuzin half‐life was 4–19 days following PP application and 3–17 days following PRE application. The metribuzin concentration did not exceed 65 μg kg−1 at the 5–10 cm or 10–20 cm depths in any treatment, indicating that little metribuzin had leached from the surface soil after PP or PRE application. The finding of a higher metribuzin concentration at 5‐20 cm depth in tilled plots than in no‐till could be attributed to higher initial soil concentrations in the absence of crop residue.
Trifluralin effects on the development of cotton in arid zone soils
Authors: DORNAI D. , GERSTL Z. , CHEN Y. , MINGELGRIN U. 
Published: July 2006

Summary:The effect of trifluralin on the growth and development of cotton plants in low‐organic‐matter soils from the northern Negev of Israel was studied. Trifluralin exhibited linear sorp tion isotherms on these soils, Trifluralin and dinitramine losses from soils under varying moisture regimes and application practices were determined in open systems. The data were fitted to both first‐order and biexponential kinetic equations. In about 50% of cases the biexponential kinetic model provided a better fit to the data, but no relationship could be found between the model parameters and environmental or soil properties. Losses were generally greater at field capacity than at 50% field capacity, and at 27°C than at 15°C, and in soils with a lower organic matter content. The trifluralin application rate was negatively correlated with vegetative growth parameters of cotton, but the correlation became weaker with increasing soil organic carbon content. Trifluralin delayed boll production in coarse textured soils, the longest delay occurring at higher application rates. It is concluded that in light soils that contain very little organic matter, trifluralin rates must be maintained at the minimum level required for adequate weed control to prevent damage to crops.
Cirsium arvense (L.) Scop. competition with winter wheat (Triticum aestivum L.)
Authors: MCLENNAN B. R. , ASHFORD R. , DEVINE M. D. 
Published: July 2006

Summary:A series of field experiments was conducted to evaluate the competitive effect of Cirsium arvense (L.) Scop. on winter wheat (Triticum aestivum L. ‘Norstar’) yield. Grain yield at the centre of dense C. arvense patches ranged from 28–71% of the yield in adjacent weed‐free plots, based on measurements made at 11 experimental sites over a 2‐year period. The mean reduction in yield was 49%. Two models were used to describe grain yield reduction in terms of C. arvense shoot density: (a) linear regression of percentage yield reduction on the square root of shoot density, and (b) non‐linear regression, based on a rectangular hyperbola. Both models give similar yield loss estimates at commonly occurring shoot densities of C. arvense, but the non‐linear model accounted for more of the observed variation in grain yield. The major yield component affected by C. arvense competition was spikes per unit area, with kernel weight affected to a lesser extent.
Herbicidal control of Cirsium arvense (L.) Scop, roots and shoots in no‐till spring wheat (Triticum aestivum L.)*
Authors: DONALD W. W. 
Published: July 2006

Summary: Résumé: ZusammenfassungThree herbicide treatments were applied each year over a period of 4 years to Cirsium arvense (L.) Scop, infestations in no‐till spring wheat (Triticum aestivum L.) in North Dakota, USA. Both chlorsulfuron at 30 g ai ha−1+a non‐ionic surfactant and a mixture of clopyralid+2,4‐D at 70+280 g ai ha−1 gradually reduced Cirsium arvense shoot density, root biomass, and adventitious root buds over the 4‐year treatment period in two trials. These two treatments did not merely induce adventitious root buds to become dormant. They virtually eliminated roots to a depth of 50 cm by year 4. Tribenuron methyl at 10 g ai ha−1+ a non‐ionic surfactant was less effective in reducing shoot density and root biomass. Lutte herbicide contre les racines et les tiges de Cirsium arvense (L.) Scop, dans du bli de printemps non laboure (Triticum aestivum L.) Trois traitements herbicides ont été appliqués chaque année pendant 4 ans, contre des infestations de Cirsium arvense (L.) Scop, dans du blé de printemps (Triticum aestivum L.) non labouré dans le Dakota Nord, USA. Tant le chlorsulfuron à 30 g m.a. ha−+un surfactant nonionique qu'un mélange de clopyralide+2,4‐D à 70+280 g m.a. h− ont reduit progres‐sivement la densité des pieds de Cirsium arvense, la biomasse racinaire, et les bourgeons racinaires adventices pendant les 4 années de traitements dans les 2 essais. Ces traitements ont à peu près éliminé les racines sur une profondeur de 50 cm en 4 ans. Ces deux traitements n'ont pas induit de dormance des bourgeons racinaires adventices. Le tribenuron methyl à 10 g m.a. ha−+un surfactant non ionique a été moins efficace dans la réduction de la densité de plante et de la biomasse racinaire. Chemische Bekämpfung von Cirsium arvense (L.) Scop, in direktgesätem Sommerweizen (Triticum aestivum L.) In direktgesäter Sommerweizen (Triticum aestivum L.) wurdel in North Dakota. USA, Bestände von Cirsium arvense (L.) Scop, über 4 Jahre jährlich 3 Herbizidbehandlungen unterzogen. Sowohl Chlorsulfuron mit 30 g AS ha−1 nichtionischem Netzmittel als auch eine Mischung von Clopyralid+2,4D mit 70+280 g AS ha−1 verringerten die Sproßdichte der Acker‐Kratzdistel, die Wurzelbiomasse und die Adventivknospen an den Wurzeln in 2 Ver‐suchen graduell. Durch diese beiden Behand‐lungen wurden nicht nur die Adventivknospen dormant, sondem auch die Wurzeln bis zu einer Tiefe von 50 cm bis zum 4. Jahr fast ganz elimi‐niert. Tribenuron‐methyl mit 10 g AS ha−1 nichtionischem Netzmittel war hinsichtlich der Reduktion von Sproßdichte und Wurzelbiomasse weniger wirksam.
Soil solarization in Greece
Authors: VIZANTINOPOULOS S. , KATRANIS N. 
Published: July 2006

Summary: Résumé: ZusammenfassungSoil solarization (SS) was tested in outdoor conditions in mid Greece by mulching wet soil with transparent polyethylene sheets to examine its effectiveness as a weed control treatment in maize and soybean planted as second season crops. Three or 4 weeks of solarization gave bet‐ter weed control than preemergence herbicides and effectively controlled volunteer wheat (Triticum aestivum), Portulaca oleracea, Digitaria sanguinalis, Solanum nigrum, Amaranthus spp. and other weeds. The weed control effects lasted for more than 4 months. In mulched soil the maximum temperature at 7.5 cm depth was generally 7–9°C warmer than in the unmulched soil. Polyethylene thicknesses of 0.015–0.030 mm were equally effective. Plants grown on solarized plots out yielded those on clean weeded hoe treatments. The weed flora present caused maize and soybean losses of 20–48%. These losses would economically justify the use of polyethylene mulches. Solarisation du sol en grece La solarisation du sol (SS) a été testée en conditions extérieures en Grèce centrale, en recouvrant le sol humide avec des feuilles de polyéthylene transparent pour examiner son efficacité comme traitement herbicide sur du ma'is et du soja plantés comme secondes culturesde la saison. Trois ou 4 semaines de solarisation ont donné une meilleure destruction des adventices que des herbicides de pré1evée et ont détruit efficacement les repousses de blé (Triticum aesti‐vum), Portulaca oleracea, Digitaria sanguinalis, Solanum nigrum, Amaranthus spp. et d'autres adventices. Les effets herbicides ont duré plus de 4 mois. Dans le sol couvert le maximum de témpérature à 7.5 cm de profondeur a été généale‐ment de 7–9°C plus chaud qu'en sol nu. Des épaisseurs de polyéthylene de 0,015–0,030 mm ont é'té pareillement efficaces. Les plantes cul‐tivées sur parcelles solarisées produisent autant que celles sur des sols tenus propres par binage. La flore adventice présente a entrainé des pertes de maïs et de soja de 20–48%. Ces pertes justi‐fieraient économiquement l'utilisation de films de polyéthylène. Boden‐Solarisation in Griechenland In Mittelgriechenland wurde die Solarisation feuchten Bodens, überdeckt mil transparenter Polyethylenfolie, auf ihre Wirksamkeit zur Unk‐rautbekämpfung in Mais und Sojabohnen als 2. Kultur der Vegetationsperiode untersucht. Mit 3 oder 4 Wochen Solarisation ließen sich Weizenaufschlag (Triticum aestivum), Portulaca oleracea, Digitaria sanguinalis, Solanum nigrum, Amaranthus spp. und andere Unkräuter besser als mil Vorauflauf‐Herbiziden bekämpfen. Die Wirkung hielt > 4 Monate an. Bei der Solarisa‐tion lag die Bodentemperature in 7,5 cm Tiefe um 7.9°C höher als bei offenem Boden. Folien von 0,015.0,030 mm Stärke waren gleich wirk‐sam. Der Ertrag lag in den solarisierten Parzellen über dem gehackter Parzellen. In den unbehan‐delten Parzellen ging der Ertrag um 20.48% zurück, so daß die Solarisation unter Polyethylenfolie ein wirtschaftliches Verfahren ist.