bluuebunny/crossref_metadata_2025_split huggingface dataset:
The adsorption of atraton and monuron by soils at different water contents
Authors: HANCE R. J. 
Published: July 2006

Summary:Estimates of adsorption by soil at water contents down to less than wilting point were obtained with a three phase system of soil‐water‐immiscible organic solvent. The method is restricted to solutes with a water‐organic solvent partition ratio of between about 10 and 0.5 if analytical errors are to be acceptable. With the two soils used the results with atraton and monuron were similar. There was little change in adsorption as soil water content was reduced until the level approached that needed to produce a monolayer on the soil surfaces, when it increased sharply. There were no differences at water contents between field capacity and wilting point.
Chemical control of marsh ragwort (Senecio aquaticus Huds.) in established grassland
Authors: FORBES JAMES C. 
Published: July 2006

Summary:Infestations of marsh ragwort, Senecio aquaticus Huds., in established ley grassland were sprayed at the rosette stage in April or May with MCPA, 2,4‐D, asulam or a 2,4‐D asulam mixture. All treatments gave better control in the year after spraying than in the year of spraying. The most effective herbicide was 2,4‐D ester at 1–68 or 1–12 kg/ha with or without the incorporation of asulam at 1–12 kg/ha. MCPA at 1–68 kg/ha was less effective, especially in the year of spraying and asulam alone at 1‐12 kg/ha gave consistently the poorest control of all treatments. Spraying in May gave better control in the year of spraying than April application, but in the year after spraying date of application made no difference to the degree of control. S. aquaticus at the various sites differed in general susceptibility to herbicides in the year of spraying, but in the year after spraying these differences disappeared.
Effect of four herbicides and two oils on leaf‐cell membrane permeability*†
Authors: PRENDEVILLE G. N. , WARREN G. F. 
Published: July 2006

Summary:Leakage of electrolytes from leaf discs of treated Phaseolus Vulgaris L. plants was the main criterion used to study the effect of several chemicals on the permeability of leaf‐cell membranes. Paraquat, diquat, dinoseb and oxyfluorfen (2‐chloro‐1‐(3‐ethoxy‐4‐nitrophenoxy)‐4‐(Trifluoromethyl) benzene) increased leaf‐cell membrane permeability after exposure for 12 h or less. An‘aromatic’oil caused a large increase in permeability at 2–5 min after treatment. Increases in electrolyte release were also correlated with release of soluble amino acids from the leaf discs but the former method was the more sensitive. Increase in cell membrane permeability was always associated with injury symptoms such as appearance of necrotic areas in leaves. Chlorpropham, linuron, sodium azide, glyphosate and 2,4‐D at 10−3M, as well as 1% X‐77 surfactant and a non‐phytotoxic isoparaffinic oil did not alter leaf‐cell permeability at 12 h after treatment.Light was necessary for paraquat and oxyfluorfen to alter leaf cell permeability. Paraquat and oxyfluorfen caused a greater increase in leaf‐cell permeability of a soybean mutant with yellow leaves as compared with the normal green leaves. With oxyfluorfen this difference in permeability was greater than with paraquat, and was associated with the appearance of severe necrotic injury symptoms in the yellow mutant; paraquat caused no injury symptoms.
Control of Cirsium arvense (L) Scop, by herbicides and mowing
Authors: AMOR R. L. , HARRIS R. V. 
Published: July 2006

Summary:The efficacy of mowing and of herbicides (applied by spot spraying or boom spraying) for the selective control of Cirsium arvense (L) Scop, in Victorian pastures was investigated. The pastures were based on Trifolium repens L. and Lolium perenne L.A general decline in the number of thistle shoots in untreated plots at three out of five sites was recorded.‘Tordon 50‐d' (5% a.i. picloram and 20% a.i. 2,4‐D as triisopropanolamine salts), MCPB, 2,4‐DB and mowing resulted in suppression, but not eradication, during the experimental period. MCPB and 2,4‐DB are the most suitable herbicides for selective control. The use of‘Tordon 50‐d' is restricted by its effect on clovers, soil persistence and cost.Variable growth of C. arvense, associated with variable summer rainfall in Victoria, increases the difficulty in controlling this weed and necessitates a persistent long term approach.
The nutritive value of Echium plantagineum L. and Trifolium subterraneum L.
Authors: PIGGIN C. M. 
Published: July 2006

Summary:Echium plantagineum is a widespread, persistent, highly productive and often dominant species in southern Australia. In pastures, it usually occurs with Trifolium subterraneum. which is commonly regarded as a valuable forage species. However, there is considerable controversy over the value of E. plantagineum as a pasture species.In this study, the nutritive value (dry matter content, in vitro digestibility, nitrogen content) of herbage of E. plantagineum and T. subterraneum generally was similar at any time during the year. It is concluded that E. plantagineum is a useful forage species because it is highly productive, is readily eaten by grazing stock and has a relatively high nutritive value.
Population flux and mortality in a ragwort (Senecio jacobaea L.) infestation
Authors: FORBES JAMES C. 
Published: July 2006

Summary:Actuarial data on the progress through the life‐cycle and the death of individual plants of Senecio jacobaea in permanent pasture were obtained over a period of one year by repeated mapping of all the plants in twenty permanent quadrats. The data were used to construct a model of population flux and mortality in a hypothetical population in which germination, maturation and death were constant from year to year and equal to those in the real population in the year of study. In the hypothetical population 57% of all plants died as seedlings. 35% as vegetative rosettes and 8% immediately after flowering. Of plants which flowered in the first 2 years or survived into a third year 8% were annuals or winter annuals, 39% were biennials and 53% were perennials.
Tuber composition in yellow nutsedge (Cyperus esculentus (L.)) variants
Authors: MATTHIESEN R. L. , STOLLER E.W. 
Published: July 2006

Summary: Résumé: ZusammenfassungYellow nutsedge variants from California, Georgia, Illinois, Maryland, Minnesota and Oklahoma were analysed for intraspecific differences in tuber composition. Tuber size varied from 70 to 710 mg. Carbohydrates ranged from 45 to 77% of tuber dry weight. Starch was the most abundant carbohydrate in all the tubers. The saccharides, fructose, glucose, sucrose and melibiose were found at least in trace quantities in all the tubers; only tubers of the Georgia and Maryland variants contained significant quantities of all four saccharides, and the other three variants containted principally sucrose. Triglycerides constituted more than 80% of the lipids in the tubers. The major acid present in all tubers was oleic. Composition du tubercule chez divers biotypes de Cyperus esculentus (L.)Des biotypes de Cyperus provenant de Californie, de Géorgie, de l'Illinois, du Maryland, du Minnesota et de l'Oklahoma ont été analysés en vue de rechercher des différences intraspécifiques dans la composition du tubercule. Le poids du tubercule a varié de 70 à 710 mg. Les hydrates de carbone représentaient de 45 a 77% du poids sec du tubercule. L'amidon a été l'hydrate de carbone le plus abondant dans tous les tubercules. Les saccharides: fructose, glucose, saccharose et mélibiose ont été trouvés au moins à l'état de traces dans tous les tubercules; seuls les tubercules des biotypes de Géorgie et du Maryland contenaient des quantités significatives des quatre saccharides et les trois autres biotypes contenaient principalement du saccharose. Les triglycérides constituaient plus de 80% des lipides des tubercules. Le principal acide gras présent dans tous les tubercules était l'acide oléique. Inhaltsstoffe der Knollen verschiedener Herkünfte von Cyperus esculentus (L.)Herkünfte von Cyperus esculentus aus Kalifornien, Gorgia, Illinois, Maryland und Oklahoma wurden auf Unterschiede in ihrer Knollenzusammensetzung untersucht. Die Knollenge‐wichte variierten zwischen 70 und 710 mg. Die Kohlenhydratgehalte schwankten von 45 bis 77% des Knollentrockengewichtes. Stärke war in alien Knollen das häufigste Kohlenhydrat. Die Saccharide Fructose, Glucose, Sucrose und Melibiose waren in alien Knollen zumindest in Spuren festzustellen. Lediglich Knollen aus Gorgia und Maryland enthielten größere Mengen aller 4 Saccharide. DieTestlichen 3 Herkünfte enthielten haupt‐sächlich Sucrose. Triglyceride bildeten mehr als 80% der Knol‐lenlipide. Die häufigste Fettsäure war Ölsäure.
The long term decline of a population of Avena fatua L., with different cultivations associated with spring barley cropping
Authors: WILSON B. J. 
Published: July 2006

Summary:The decline of a population of A. fatua established in September 1971, and not allowed to seed thereafter, was monitored in three successive barley crops Numbers of viable seeds in the son in June fell from 159 m2 in 1972 to 1 m2 in 1974 declining by 83° in the first, and by 96° in the second year. Seedling numbers fell from 138 m2 in 1972 to 9 m2 in 1974, declining by 32° in their first and by 89° in the second year. The slower decline of seedling numbers in the first year was attributed to loss of dormancy of seed reserves giving proportionally more seedlings in the second spring.Cultivations had no major influence on the pattern of seedling emergence in the spring, but they did affect population level. Where the stubble was cultivated immediately after seeding in September 1971, twice as many seedlings and three times as many seeds in the soil were present in 1972 compared with delayed autumn cultivations in 1971. From this greater reserve of seeds in the soil more seedlings arose in 1973 and in 1974. Time cultivation in the winter of 1971 resulted in slightly more seedlings in 1972 than did ploughing; this greater population declined more rapidly with line cultivation in 1973 and 1974. It is suggested that with no herbicidal control annual line cultivation will lead to a more rapid build up than ploughing: where A. fatua is controlled, the decline should be more rapid with tne cultivation. Persistence of A. fatua as a weed in arable situations seems related more to survivors shedding seeds than to the persistence of seeds on the soil. Factors which may influence the persistence of seeds in the soil are discussed.
Recovery from inhibition of photosynthesis by metamitron in various plant species
Authors: VAN OORSCHOT J. L. P. , VAN LEEUWEN P. H. 
Published: July 2006

Summary:Inhibition of photosynthesis by metamitron in the rooting medium and its subsequent recovery after transfer of the roots to herbicide‐free nutrient solution was measured in eight plant species.Fast and complete recovery within a few hours after treatment showed that metamitron, once absorbed, was rapidly and completely inactivated in the leaves of sugar beet (Beta vulgaris L.). Inactivation in perennial ryegrass (Lolium perenne L.) was slower and incomplete. It was low in Echinochloa crusgalli (L.) P.B., Amaranthus retroflexus L., Alopecurus myosuroides Huds. and bean (Phaseolus vulgaris L.), and undetectable in maize (Zea mays L.) and Portulaca oleracea L.From the transpiration rate and the concentration of metamitron in the nutrient solution that just did not cause inhibition of photosynthesis in sugar beet, uptake and inactivation rates per unit leaf area were calculated to be at least 18·5 ng/cm2/h. The same external concentration markedly depressed photosynthesis in the other more susceptible species.After leaf sprays sugar beet plants gradually resumed the normal rate of photosynthesis, but bean plants did not recover.
Translocation of 2,4‐D, asulam and amitrole in water hyacinth
Authors: SINGH S.P. , MÜLLER F. 
Published: July 2006

Summary:In glasshouse experiments foliar application or 14C‐labelled herbicides to water hyacinth plants at the 4‐leaf stage indicated that amilroie transport from the treated leaf blade was faster and greater than 2.4‐D. but a little less than asulam. From the treated leaf 14·2, 25·9. 39·7. 44·5 and 51·8% of the recovered 14CNamitrole was translocated at intervals of 6 h. and 1. 3. 6 and 12 day., respectively. Both xylem and phloem transport of asulam and amitrole was evident, whereas 2.4‐D moved only from ‘source to sink’.Movement of the herbicides from the mother to the connected daughter plant or vice versa was dependent upon the size of the latter. Maximum transport of these herbicides in either direction took place at the 2‐leaf stage of daughter plants. With any increase or decrease in the number of leaves on daughter plants, the transport of herbicides was reduced. As an exception, daughter plant to mother plant movement of amilroie was maximum at the 1‐leaf stage.After extraction, fractionation and TLC separation of foliage applied 14C‐2.4‐D 76–4 and 72·1% of the radioactivity was detected in the chloroform phase of the leaf extract at 3 and 6 day intervals, respectively.In another pot culture experiment, it was observed that after spraying the mother plants with 2.4‐D‐amine at 0–75 kg/ha the connected daughter plants at 1 to 4‐leaf stages werckilled if the culture solution was contaminated while spraying, or by dying leaves. When contamination was totally avoided, the connected but unsprayed daughter plants at 3 to 4‐feaf stages survived.
Herbicide tank‐mixing for post‐emergence weed control in sugar beets
Authors: GIANNOPOLITIS C. N. , STROUTHOPOULOS TH. G. 
Published: July 2006

Summary:Tank‐mixtures of selective herbicides were evaluated for 2 years on field‐grown sugarbeets under two weed flora situations: (a) mixed floras of broad‐leaved and grass weeds and (b) weed floras of broadleaves grown beyond their stages of greatest sensitivity to herbicides. In these situations single herbicides usually fail to provide satisfactory post‐emergence weed control in sugarbeets.Of several tank‐mixtures, which could be devised for use in the first situation, ethofurnesate + Betanal AM 11, diclofop‐methyl + Betanal AM 11 and diclofop‐methyl + metamitron gave synergistic phytotoxicity to sugarbeet seedlings. Synergism in weed control, becoming apparent by an accelerated appearance of the herbicidal effects, was obtained with the mixture alloxydimeton + Betanal AM 11. This mixture was not phytotoxic and appears to be the most efficient for simultaneous control of broad‐leaved and grass weeds.From trials in the second situation it became apparent that the activity of metamitron, which was reduced on older weeds, could be restored by mixing with a non‐phytotoxic oil or a low dose of Betanal AM 11. These mixtures should be useful when growth of sugarbeets has been retarded by carried‐over herbicides, drought, frost, etc.
Differences intraspecifiques chez Convolvulus arvensis L.*
Authors: GARCIA‐BAUDIN J. M. , DARMENCY H. 
Published: July 2006

Résumé:Divers aspects de la biologie du liseron sont abordés dans ce travail à travers l'étude comparative de populations d'origine française et espagnole. Le poids des semences, la caryologie, les résultats del'électrophorése des protéines séminales solubles, la morphologic foliaire et l'aptitude à la floraison, ont été les caractères utilisés. L'observation des plantes cultivées ensemble à Madrid et la comparaison des électrophorégrammes ont permis de proposer un schéma de différenciation intraspécifique chez Convolvulus arvensis L., en se fondant principalement sur l'influence de sa répartition géographique, facteur rendant bien compte des variations enregistrées. Ce phénomène introduit un élément supplémentaire de variation pouvant affecter la réussite des traitements herbicides.
The influence of herbicides, nitrogen fertilizer, seed rate and method of sowing, on the establishment and long‐term composition of a perennial ryegrass ley.
Authors: AGGAR R. J. H 
Published: July 2006

Summary:Changes in ihe species composition of a ryegrass pasture were examined over a 2 year period from a spring establishment. Seed of S23 perennial ryegrass was sown in main plots, eilher broadcast or drilled, at rates of 15, 25 or 35 kg/ha in a field experiment at Oxford. The whole area was oversown withfour weed grasses (Agrostis siolonifera.Holcus lanatus. Poa annua and P trivialis). Five cultural and three herbicide treatments were applied across the plots. These consisted of three levels of nitrogen (0. 50 and 100 kg N per ha), two companion species (Italian ryegrass and white clover) and 2.4‐D, benazolin and methabenzihiazuron applications.Ten weeks after sowing, broad‐leaved weeds accounted for nearly half the lotal dry‐matter yield, except where controlled by the three herbicides. Grass yields were nol increased by herbicide treatment. The only cultural treatment checking broad‐leaved weeds was ihe 35 kg/ha seeding rale.Seven months after sowing, the only treatment which had decreased the abundance of weed grasses was melhabenzthiazuron especially againsi A. stolonifera and Poa spp. Two years afler sowing, perennial ryegrass had only 34% ground cover and had been replaced largely by H. lanatus (38%), Poa spp, (15%) and A. stolonifera (7%), Where methabenzthiazuron had been used the ryegrass ground cover was 48%. with less P. trivialis and A. stolonifera. but H. lanatus was nol altered. White clover decreased H. lanatus cover.In two supplementary pot experiments, methabenzthiazuron sprayed pre‐emergence damaged perennial ryegrass unless the seed was covered with at least 4 mm of soil. Only H. lanatmand F. rubra out of sixteen grasses were relatively resistant to methabenzihiazuron when applied at ihe tillering stage, confirming that this herbicide has potential for preventing the ingress of many unsown grasses in new leys.
Persistence of dichlobenil in a sandy soil and effects of residues on plant growth
Authors: WILLIAMS JOHN H. , EAGLE DAVID J. 
Published: July 2006

Summary:The persistence of dichlobenil following the application of dichlobenil granules was studied in a replicated plot experiment including both surface and incorporated treatments of 8·3 and 16·6 kg/ha ai. Soil analyses showed an initial half‐life of about 4 weeks but the persistence increased with time and a year after application the half‐life was about 1 year. Incorporation of the granules into the soil markedly increased the persistence of dichlobenil and its metabolite dichlorobenzamide. The most sensitive crop was carrot which was damaged by residues of only 1–2% of the recommended dose. Residues phytotoxic to carrots persisted for 2 years from the 8·3 kg/ha surface application and 5 years from the 18·6 kg/ha incorporated application. Lettuce was also highly sensitive to residues.
Factors affecting glyphosate activity in Imperata cylindrica (L.) Beauv. and Cyperus rotundus L. II: effect of shade
Authors: MOOSAVI‐NIA H. , DORE J. 
Published: July 2006

Summary: Imperata cylindrica and Cyperus rotundus were grown under three different light regimes; unshaded, 50% shade, and 75% shade and no shade plus 75% shade before and after spraying, (temporary shade) in a heated greenhouse. Six weeks after the start of the experimenis, glyphosate was applied to the plants at 0·2, 0·4 and 0·8 kg/ha (for Imperata) or 0·3, 0·6 and 1·2 kg/ha (for Cyperus). Glyphosate toxicity was enhanced as shade increased. In Imperata, all shade regimes at all rates of glyphosate eaused greater damage to the plants than the unshaded regime. The reduction in shoot dry weight, rhizome dry weight and total carbohydrate content of Imperate rhizotties at 75% continuous and temporary shaiie conditions, with the lowest rate of glyphosate, was almost twice as much as the reduction in the same features m the unshaded plants caused by the highest rate of glyphosate. In Cyperus. glyphosate at the intermediate and highest rates decreased the shoot dry weight at 75% continuous shade by 79% and 98% respectively. Plants in 50% shade were significantly affected only at the highest rate of glyphosate. Sprouting ability of the tubers al 75% continuous shade was inhibited when the tubers were replanted for recovery. Enhanced toxicity of glyphosate in reduced light intensity was attributed to the morphological changes in the nature of the leaves caused by shade.
Determination of extractable and non‐extractable radioactivity from prairie soils treated with carboxyl‐ and ring‐labelled [14C]2,4‐D
Authors: SMITH ALLAN E. , MUIR DEREK C. G. 
Published: July 2006

Summary:Ring‐ and carboxyl‐labelled [14C]2,4‐D were incubated under laboratory conditions, at the 2 g/g level, in a heavy clay, sandy loam, and clay loam at 85% of field capacity and 20 1C. The soils were extracted at regular intervals for 35 days with aqaeous acidic acetonitrile, and analysed for [14C]2,4‐D and possible radioactive degradation products. Following solvent extraction, a portion of the soil residues were combusted in oxygen to determine unextracted radioactivity as [14C]carbon dioxide. The remaining soil residues were then treated with aqueous sodium hydroxide, and the radioactivity associated with the fulvic and humic soil components determined.In all soils there was a rapid decrease in the amounts of extractable radioacitivity, with only 5% of that applied being recoverable after 35 days. All recoverable radioactivity was attributable to [14C]2,4‐D, and no [14C]‐containing degradation products were observed. This loss of extractable radioactivity was accompanied by an increase in non‐extractable radioactivity. Approximately 15% of the applied radioactivity, derived from carboxyl‐labelled [14C]2,4‐D, and 30% from the ring‐labelled [14C]2,4‐D was associated with the soil in a non‐extractable form, after 35 days of incubation.After 35 days, less than 5% of the radioactivity from the carboxyl‐labelled herbicide, and less than 10% of the ringlabelled material, was associated with the fulvic components derived from the three soils. Less than 5% of the applied radioactivities were identifiable with any of the humic acid components.It was considered that during the incubation [14C]2,4‐D did not become bound or conjugated to soil components, and that non‐extractable radioactivity associated with the three soil types resulted from incorporation of radioactive degradation products, such as [14C]carbon dioxide, into soil organic matter.
The effect of CGA 43089 as a safener of metolachlor in sorghum (Sorghum bicolor) (Recordings of elongation rates on single sorghum leaves)
Authors: CHRIST R.A. 
Published: July 2006

Summary:The influence of metolachlor [2‐chloro‐6‐ethyl‐N‐(2‐methoxyl‐methylethyl)acet‐o‐toluidide] on sorghum (Sorghum bicolor Moench.) is first demonstrated in order to be able to show the difference observed when this herbicide is applied together with CGA 43089. The effect of various concentrations (in nutrient solution) and of various exposure times on the elongation rate of single leaves is demonstrated.The safener CGA 43089 (x‐(cyanomethoximino)‐benzacetonitrile] showed no effect on the elongation rates when used in normal concentrations. The combined application of safener and metolachlor (concentration ratio 1:3) prevented the growth reductions due to metolachlor. When the safener was applied before metolachlor the safening action was as good as that of the combined application. When the safener was applied 1 or 2 days after the herbicide the safening effect was diminished. Plant uptake of the safener over a period of 3 days was sufficient to prevent the action of metolachlor but the safening effect was reduced when the interval between the end of safener application and the beginning of the herbicide application was increased. The conclusion drawn regarding the mode of action is that CGA 43089 does not interfere with herbicide uptake into the plant. The safener is, however, able to reduce the active amount of herbicide when present at the right time at the site of effect.