bluuebunny/crossref_metadata_2025_split huggingface dataset:
The response of hill bracken and the associated pasture to applications of picloram and dicambra
Authors: FARNWORTH J. , DAVIES G. M. 
Published: July 2006

Summary: Résumé: ZusammenfassungPicloram and dicamba applied as sprays or granules at equal doses reduced the vigour of bracken, and there was a corresponding increase in pasture yield. Yield of pasture dry matter and digestible organic matter was increased by over 400% on picloram plots compared with untreated plots and Agrostis spp. became dominant in the sward. Picloram produced the greatest reduction in bracken vigour. Vigour was assessed in terms of dry weight of frond laminae per unit area and total available rhizome carbohydrate per unit area. Higher doses, and granular rather than spray applications of both herbicides were most effective in reducing bracken vigour. Out of twenty‐one correlations tested over a 3‐year period, bracken frond lamina dry weight yield showed the best relationship with pasture dry matter yield.Réponse de la fougére et de la pâture associée à des applications de piclorame et de dicambaLe piclorame et le dicamba appliqués sous forme liquide ou sous forme de granulés, à des doses égales, ont réduit la vigueur de la fougàre et il s'est manifesté un accroissement correspondant du rendement de la pâture. Le rendement de la pâture en matiàre sàche et en matiàre organique digestible a été augmenté de plus de 400 % dans les parcelles traitées au piclorame, par rapport aux parcelles non traitées et l'Agrostis spp est devenu dominant dans la prairie. Le picloramé a provoqué la plus forte réduction de la vigueur de la fougàre. La vigueur a été exprimée en termes de poids sec de feuilles de frondes et en carbohydrates totaux disponibles dans les rhizomes, par unité de surface. Les doses les plus fortes et les granulés, plus que les pulvérisations, furent les plus efficaces quant à la réduction de la vigueur de la fougàre. Des 21 corrélations examinées durant une période de trois ans, il ressort que le rendement, en poids sec, des feuilles de frondes de fougàres a montré la meilleure relation avec le rendement en matiàre sàche de la pâture.Die Reaktion von Adlerfarn und der von ihm besiedelten Weide auf Behandlungen mit Picloram und DicambaSprintzungen und entsprechende Aufwandmengen als Granulate von Picloram und Dicamba verminderten die Wuchsigkeit des Adierfarns und bewirkten einen Ertrags‐zuwachs der Weide. Der Ertrag an Trockensubstanz der Weide und die verdauliche organische Substanz, nahmen in den Picloramparzellen, verglichen mit Unbehandelt, um über 400 % zu und Agrostis spp. wurden vorherrschend. Picloram drängte den Adlerfarn am stärksten zurück. Die Wüchsigkeit wurde an Hand des Wedeltrockengewichts je Flächeneinheit und verfägbarer Rhizomkohlenhydrate je Flächeneinheit gemessen. Bei beiden Herbiziden wurde der Adlerfarnwuchs durch höhere Aufwandmengen und Anwendung in Granulat‐form stärker vermindert als durch Spritzungen. Von den Versuchsergebnissen aus drei Jahren, zeigten von 21 geprüften Korrelationen das Wedeltrockengewicht des Adierfarns mit dem Trockensubstanzertrag der Weide, die beste Beziehung.
Activated‐carbon and ash‐carbon effects on the adsorption and phytotoxicity of diuron
Authors: TOTH J. , MILHAM P. J. 
Published: July 2006

Résumé: Zusammenfassung: SummaryCarbon produced by burning paspalum (Paspalum dilatatum L.) under a wide range of conditions (ash‐C) adsorbed appreciable quantities of diuron from aqueous solution. However, commercially activated‐C was a more efficient adsorbent than any of the ash‐C products whose activity was related to their conditions of formation. Broadcast activated‐C at a C/diuron ratio ≤5/1 (w/w) prevented death of barley (Hordeum vulgare L.) seedlings receiving the highest diuron treatment (32 kg ha−1); although 0–8 kg ha−1 killed the plants in its absence. Only one of the two ash‐C products tested caused a significant reduction in the phytotoxicity of ≥16 kg diuron ha−1. Death of plants was delayed. However, the bioassay was not sufficiently sensitive to measure the smaller reduction in phytotoxicity caused by the other ash‐C treatment. Effets d'un charbon actif et de charbons de cendres sur l'adsorption et la phytotoxicité du diuron Les charbons des cendres obtenues en faisant brüler du paspalum (Paspalum dilatatum L.) dans une série étendue de conditions ont adsorbé des quantités appreciates de diuron a partir d'une solution aqueuse. Toutefois, un charbon actif du commerce se révéla comme un adsorbant plus efficace qu'aucun des charbons obtenus dont l'activité fut en rapport avec les conditions de leur obtention. Un poudrage avec du charbon actif dans une proportion pondérale de 5 parties au minimum de carbon pour une partie de diuron a prévenu la destruction de plantules d'orge (Hordeum vutgare L.) ayant reçu le traitement á la dose la plus élevée de diuron (32 kg/ha) alors qu'en l'absence de charbon actif, les plantules furent tuées á la dose de 0.8 kg/ha. Un seul des deux charbons de cendres essayés provoqua une reduction significative de la phytotoxicité du diuron á la dose de 16 kg/ha. La mort des plantes fut retardée. Toutefois l'essai biologique ne fut pas suffisamment précis pour mesurer la réduction plus faible de phyiotoxicité résultant du traitement avec l'autre charbon de cend res. Die Wirkung ton Aktivkohle und Aschekohlenstoff auf die Adsorption und Phytotoxizität von Diuron Aschekohlenstoff, der auf versehiedene Weise durch Verbrennen von Paspalum ditatatum L. gewonnen wurde, adsorbierte aus wässerigen Lösungen beträchtliche Mengen an Diuron. Die vom Handel bezogene Aktivkohle wiir uber ein starkeres Adsorbens als jedes der Aschekohlenstolf‐Produkte. Ihre Wirksamkeit hing von der Art der Herstellung ab. Wenn Aktivkohle in einem Verhältnis zu Diuron von ≥5/1 (Gew./Gew.) breitwörfig ausgebracht wurde, konnte bei der höchsten Diuronbchandlung (32 kg ha−1) das Absterben von Gerstesämlingen (Hordeum vutgare L.) verhindert werden, während hereits 0.8 kg ha−1 Diuron alieine die Pflanzen abtöteten. Nur eines der beiden geprüften Aschekohlenstoff‐Produkte bewirkte bei ≤16 kg ha−1 Diuron eine gesicherte Reduktion der phytotoxischen Wirkung indem das Absterben der Pflanzen verzögert wurde. Um die geringere Wirkung des anderen Produkls zu erfasscn. war der Biotest zu unempfindlich.
The in vitro sensitivity of some species of Chlorophyceae to a selected range of herbicides
Authors: CULLIMOKE D. ROY 
Published: July 2006

SummaryA survey was undertaken to establish the sensitivity of seventeen algal strains belonging to the Chlorophyceae to a selected range of herbicides up to a concentration maximum of 10 ppm under in vitro conditions. The herbicides were found to vary considerably in their toxicity to algae and a sequence was established based upon the magnitude of this toxicity: diuron > bromacil > paraquat> monuron> diquat> linuron> 2, 4‐DB >barban> dicamba, dichlobenil, dalapon, picloram> bromoxynil, 2,3,6‐TBA > 2.4‐DP. 2,4,5‐T and EPTAM. Of the algae, the most sensitive genera were Hormidium and Haematococcus, and the strain most sensitive to a wide range of herbicides was Hormidium barlowi (strain 335/la).
Absorption and efflux of chloro‐s‐triazines by Setaria roots*
Authors: ORWICK P. L. , SCHREIBER M. M. , HODGES T. K. 
Published: July 2006

Summary:The absorption and loss of four chloro‐s‐triazines was investigated in excised roots of four Setaria taxa. Different taxa absorbed the various triazines at different rates. In general, triazine absorption was greater at 2°C than at 22.5°C, and absorption rates were linear functions of external concentrations.Efflux studies showed marked differences in the rate of loss of 14C‐atrazine, 14C‐simazine, and 14C‐propazine from root sections of robust white foxtail (Setaria viridis var. robustaalba Schreiber). The roots lost 14C‐atrazine very quickly, and the loss was similar in either water or 12C‐atrazine. Atrazine appears to be restricted to the apoplast of the root. 14C‐atrazine was lost more rapidly than either 14C‐simazine or 14C‐propazine to water or to solutions containing the unlabelled herbicide. Efflux of 14C‐simazine was greater than that of 14C‐propazine to solutions of CaCl2. From the pattern of efflux, it was concluded that 14C‐simazine and 14C‐propazine accumulated in the root symplast. Furthermore, the decreases in chloro‐s‐triazine absorption in the presence of metabolic inhibitors (dinitrophenol, sodium arsenite) may suggest that 14C‐simazine and 14C‐propazine entered the symplast by an energy‐dependent process.
Studies on the mode of action of asulam in bracken (Pteridium aquilinum L. Kuhn) I. Absorption and translocation of [14C]asulam
Authors: VEERASEKARAN P. , KIRKWOOD R. C. , FLETCHER W. W. 
Published: July 2006

Summary:Studies of the absorption and translocation of foliage‐applied ring‐labelled [14C]asulam [methyl (4‐aminobenzenesulphonyl) carbamate] were carried out using glasshouse and field‐grown bracken plants. Translocation of 14C from the treated frond was primarily according to a 'source to sink’pattern with intense accumulation of radioactivity in the metabolically active sinks viz. rhizome apices, frond buds, root tips and young frond tissue. In the case of field bracken, translocation and distribution of 14C was extensive in the rhizome system, accumulation occurring in the active as well as dormant buds situated on the non‐frond‐bearing and storage rhizome branches. Treatment of fully expanded fronds with 100μl of [14C]asulam (1 mg, 1.0–1.5 μCi) as 2 μl droplets resulted in a rapid initial uptake during the first week, followed by progressive entry and distribution with time. Basipetal translocation to the rhizome system was positively correlated with total uptake. High humidity (95%) and high temperature (30°C) stimulated uptake and subsequent basipetal translocation to a considerable degree. Uptake was greater through the stomatal‐bearing abaxial than through the adaxial cuticle. Incorporation of a surfactant (Tergitol‐7, 0.1%) increased penetration by up to 30%. Uptake declined markedly as the frond aged, while translocation was predominantly acropetal in young treated fronds, becoming exclusively basipetal when the fronds matured. Optimum uptake and maximum distribution of [14C]asulam in the rhizome and its associated buds was achieved when treatments were applied to almost fully expanded fronds. The translocated 14C (asulam and possibly some of its metabolites) showed a considerable degree of persistence in the rhizome system, 8% of the applied activity still remaining in the rhizome 40 weeks after treatment.
Laboratory trials of a new triazine herbicide (DPX 3674) on various aquatic species of macrophytes and algae
Authors: FOWLER M. C. 
Published: July 2006

Summary:The new herbicide 3‐cyclohexyl‐6‐(diméthylamino)‐1‐methyl‐1,3,5‐triazine‐2,4 (1H,3H)‐dione (DPX 3674), effective in controlling various terrestrial plants, was found in glasshouse trials to control Myriophyllum verticillatum, Potamogeton pectinatus and Vaucheria dichotoma at 1.0 ppm and Rhizoclonium hieroglyphicum and Cladophora glomerata at 0.5 ppm. A rapid reduction of the dissolved oxygen content of the water occurred during the first few days of treatment.
Detoxification of glyphosate in soil
Authors: TORSTENSSON N. T. L. , AAMISEPP A. 
Published: July 2006

Summary:Detoxification of glyphosate in not‐autoclaved and autoclaved soils was followed by bioassay with wheat. Comparisons are made with detoxification of MCPA under similar conditions followed by bioassay with spring rape. The well known pattern for microbial metabolism of MCPA with a ‘lag’‐phase preceding the rapid degradation was shown. The initial rapid inactivation of glyphosate is by adsorption, but the results also clearly indicate that the further disappearance of activity mainly depends on microbial degradation. Glyphosate does not seem to sustain microbial growth, which indicates that it is degraded by co‐metabolism. In autoclaved soil the possibility of a slight chemical degradation or an adsorption that becomes stronger with time could not be excluded.
The fate of the herbicide chlortoluron and its possible degradation products in soils
Authors: SMITH A. E. , BRIGGS G. G. 
Published: July 2006

Summary:Chlortoluron hadàhalf‐tire in soil of 4–6 weeks. The only metabolite identified was monomethyl chlortoluron, half‐life 8 weeks. 3‐Chloro‐4‐methylphenylurea hadàsimilar half‐life but was not detected in soils treated with chlortoluron or monomethyl chlortoluron suggesting that 3‐chloro‐4‐methylaniline was formed directly from monomethyl chlortoluron. This aniline hadàhalf‐life of 1–2 days in soil, initial concentrations above 5 ppm yielding dimers and trimers predominantly C — N linked. Neither the aniline nor polymeric products were detected in chlortoluron treated soils, presumably because slow formation of the aniline was followed by rapid degradation which kept concentration low.
Quantitative relationships between the weed flora after cultivation and the seed population in the soil
Authors: ROBERTS H.A. , RICKETTS MARGARET E. 
Published: July 2006

Summary:Eighty comparisons were made between the numbers of weed seedlings emerging after seedbed preparation and the numbers of apparently viable seeds extracted by sieving and flotation from samples of the top 10 cm of soil. When soil moisture was adequate, the total seedling numbers represented 3–6% of the numbers of seeds; when dry weather followed cultivation, the percentages were lower than this. The percentages were relatively high for Poa annua L. and Stellaria media (L.) Vill. but low for Chenopodium album L. and Papaver spp. Relatively high numbers of seeds of Potygonum aviculare L. gave rise to seedlings in early spring but few appeared on seedbeds prepared after mid‐May; the reverse was true for Aphanes arvehsis L. It is suggested that data of this kind could provide a basis for predicting weed floras following cultivation at any time of year from determinations of seed numbers made at the start of the year.
Adsorption and bioactivity of di‐allate, tri‐allate and trifluralin*
Authors: GROVER RAJ , BANTING JAMES D. , MORSE PAMELA M. 
Published: July 2006

Summary:Studies were conducled to cstmiate the adsorption parameter k and the bioactivity (in terms of G R50) of di‐allate [S‐2,3‐dichloroallyl N, N‐di‐isopropyl (thiocar bamate)], iri‐allate [S‐2,3,3‐trichloroallyl N, N ‐di‐isopropyl (thiocar bamate], and [trifiuralin (2,6‐dinitro N, N‐dlpropyl‐4‐trifluoromelhylaniline) in a number of Saskatchewan soil. The k values ratiged from 5 for di‐allate adsorption m Asquilh loamy sand to 315 for trifluralin adsorption on Melfort loam and were closely related to the soil organic matter content. The relative degree of adsorption was irifluralin > tri‐allate >di‐allaie. For each herbicide, the G R50 values were positively correlated wich organic matter conienl atid wilh k. It was suggested that these nonionic herbicides may be amenable to a predictive approach for field application rates in different soils. Among herbicides for any one soil, however, there was not the same relationship between G R50andk. since the G R50 was least for trifluralin and there was no significant difference between di‐allate and tri‐allate.
The basis of field tolerance of field bean and pea to dimefuron*
Authors: GLASGOW J. L. , DICKS J. W. 
Published: July 2006

Summary:Ficld bean (Vicia fab a L. cv. Maris Bead) was susceptible both to simazine and dimefuron applied to the root system in culture solution at concentrations of 0–5 and above. Pea (Pisum satirum L. cv. Kelvedon Wonder). however, exhibited significantly greater tolerance them field bean to dimefuron between concentrations of 0.5 and 1.0. The Hill activity of isolated chloroplasts from pea was more sensitive to dimefuron than that from field bean qualitative (autoradiography) and quantitative experiments dcmonstrated that root‐applied 14C dimefuron was more readily transported to the shoot system in bean than in pea. A double‐pot experiment revealed that the effective site of uptake by the field bean is the root system: foliar uptake of 14C‐dimefuron was shown, but little movement of label from the treated leaf oceurred. Adsorption of dimefuron on a calcareous loam soil was relatively low. It is concluded that fieltolerance exhibited by field bean to pre‐emergence applications of dimefuron is due principally to depth protection: in pea. retention in the root provides an additional basis iS for tolerance.
Germination tests on thirty‐two East African weed species
Authors: FENNER M. 
Published: July 2006

Summary:The seeds of thirty‐two species of common East African weeds were set to germinate in the light and in the dark. Eighteen species with more than 40% germination in the light were also germinated in leaf shade and in neutural shade of equal intensity. Germination of fifteen of these was inhibited by darkness, and of sixteen by leaf shade, with complete inhibition in six species. A high degree of dormancy was found in fourteen species. Only one species in this group responded to alternate wetting and drying of the seeds. In eight species dormancy was less in older seeds.The ecological implications of the results are briefly discussed, and comparisons made with temperate weeds.
The effects of glyphosate on the development and cell infrastructure of white mustard (Sinapis alba L.) seedlings
Authors: UOTILA M. , EVJEN K. , IVERSEN T.‐H. 
Published: July 2006

Summary:The phytotoxicity of glyphosate(N‐(phosphonomethyl glycine) to seedlings of white mustard (Sinapis alba) cultivated indoors was studied. Yellowing and wrinkling of leaves was observed, necrotic spots appeared and the elongation of the seedlings was significantly reduced at doses 0–49 kg ai/ha and above. Only when sprayed at 4–97 kg ai/ha was the effect of glyphosate 100% lethal (5–7 days after spraying) At the highest concentration of herbicide a marked decrease in chlorophyll content was found but with 0–49 kg ai/ha the chlorophyll content was found to be higher than that in the leaves of control plants.Two and fourteen days after spraying with glyphosate and the commercial product samples of leaf and stem were harvested for electron microscopy. Cellular defects in the leaves ranging from slight swelling to complete disruption of the chloroplasts were detected at the two highest herbicide doses 48 h after spraying. These defects were intensified with time und in addition other sub‐morphological changes occurred: decrease in starch grain content, an increase in the number of dictyosomes and mitochondria, disruption of tonoplasts and increase of plastoglobuli In the more central parts of stem segments the commercial product resulted in greater cellular effects than did glyphosate. It is suggested that the differences may be due to the surfactant.
Allelopathic potential of Datura stramonium L. (Thorn‐apple)
Authors: LOVETT J. V. , LEVITT JUDY , DUFFIELD A. M. , SMITH N.G. 
Published: July 2006

Summary:The effects of different concentrations of aqueous leachate of Datura stramonium seeds and leaves on germination and radicle elongation of Linum usitatissimum were examined.Germination and radicle elongation of L. usitatissimum were depressed at high leachate concentrations. Radicle elongation usually appeared more sensitive to the effects of the leachate than did germination. Preliminary investigations showed that D. stramonium leaf leachate had similar effects to those of seed leachate.Chemical analysis of the leachates by spot‐tests and by high‐voltage electrophoresis indicated the presence of tropane alkaloids, in particular scopolamine. The presence of both scopolamine and hyoscyamine was confirmed by gas chromatography/mass spectrometry. It was shown that varying concentrations of pure scopolamine and scopolamine plus hyoscyamine solutions had effects similar to those of seed and leaf leachates on germination and radicle elongation of L. usitatissimum.
Seed banks of soils under vegetable cropping in England
Authors: ROBERTS H. A. , NEILSON JUNE E. 
Published: July 2006

SummaryEstimates of viable weed seeds in soil samples taken in 1968–1975 from 89 vegetable fields in England gave a median value of 4120 m−2 in 0–15 cm. Poa annua, Stellaria media and Matricaria matricarioides occurred most frequently, and nine species accounted for 72% of all seeds found. The numbers of seeds were lower than those from a survey made a decade earlier but the species occurring most frequently were the same; M. matricarioides, however, appeared to have increased in relative importance.
Loss of herbicides from ground sprayers
Authors: COMBELLACK J. H. 
Published: July 2006

SummaryThe effect of herbicide spray losses on non‐target areas is reviewed. The parameters governing both exo‐ and endo‐losses of herbicides are delineated and the literature on the processes involved is reviewed. The reported studies of droplet drift and vapour drift are assessed. These reviews are then related to the mathematical models developed to describe the spray loss problem. Recommendations are made as to the areas of research needed to improve the predictions of herbicide losses and their effects.
The effect of shade on the growth of variegated thistle (Silybum marianum L.) and cotton thistle (Onopordum sp.)*
Authors: POOK E. W. 
Published: July 2006

SummaryThe effects of shading on growth of the annual, variegated thistle (Silybum marianum L.) and the biennial, cotton thistle (Onopordum sp.*) were studied in an unheated glasshouse during winter. The response to relative level of irradiance (r.l.i.) of both thistles was similar, seedling growth being systematically reduced with increased shading. Relative growth rates of seedlings of both thistles were virtually identical at all levels of irradiance up to 0.68 r.l.i. Light compensation points for growth were close to 0.024 r.l.i., equivalent to c. 2 W m−2 photosynthelically active radiation under the winter conditions. Increased shading progressively delayed time of initiation of leaves and decreased their total number at harvest. Apart from reduction in plant size, increased shading had only minor effects on gross seedling morphology until irradiance was reduced to less than 0.20 r.l.i. Although the thistle seedlings are quite shade tolerant, it is suggested that heavy shading by persistent pasture species in cool seasons could contribute to the control of thistle infestations in subhumid tableland environments of southeastern Australia.
EPTC persistence and phytotoxicity influenced by pH and manure
Authors: LODE O. , SKUTERUD R. 
Published: July 2006

SummaryThe degradation of EPTC and consequently its phytotoxicity to ryegrass (Lolium perenne L.) was greatly influenced by the pH in the three sail types tested. On raising the pH from approximately 5 to 7 the microflora and the degradation in the soil increased and the phytotoxic period was shortened by 2–3 weeks in glasshouse experiments. A similar increase in degradation of EPTC was also found on adding manure.The results indicated that EPTC could be ineffective in soils with high microbiological activity. On the other hand, a delayed breakdown of EPTC on acid soils could result in damage to the crops. In the period 2–4 weeks alter the disappearance of phytotoxicity there was an increase in the yield of ryegrass. This corresponded to a concentration of 0.1 g/g or less of EPTC in the soil.