bluuebunny/crossref_metadata_2025 huggingface dataset:
The selective control of grasses in red clover (Trifolium pratense) and lucerne (Medicago sativa) crops by carbetamide and propyzamide
Authors: HAGGAR R.J. , OSWALD A.K.
Published: July 2006

Carbetamide at doses up to 3 kg/ha and propyzamide at 1–25 kg/ha applied in February to two crops each of red clover (Trifolium pratense L.) and lucerne (Medicago sativa L.) caused no crop damage to either species. Flowering of red clover was substantially increased by both herbicides. Lolium perenne (L.) and Lolium midriflorum (Lam.) in red clover were completely controlled by carbetamide at less than 2 kg/ha; removal of these grasses resulted in significant increases in yield of red clover. Poa aimtia (L.) and other grasses were less well controlled in the lucerne crops.

Le déskerhage sélectif contre les graminées dans le trèfle rouge (Trifotium pratense) et la luzerne (Medicago sativa) acec le carbétamide et le propyzamide.

Le carbétamide à des doses allant jusqu'à 3 kg/ha et le propyzamide à 1,25 kg/ha appliqués en février à deux cultures de tréfle rouge (Trifolium pratense L.) et de luzerne (Medicago sativa L.) n'ont pas causé de dommages à ces deux espèces. La floraison du trèfle rouge a été notablement accrue par les deux herbicides. Lolium perenne (L.) et Lolium muliljiorum (Lam.) ont été complètement détruits par le carbétamide à moins de 2 kg/ha. L'élimination de ces deux mauvaises herbes a provoqué des augmentations sjgnificatives de rendement du trèfle rouge. Poa annua (L.) et d'autres graminées ont été moins bien combattues dans les cultures de luzerne.
Etude des phénomènes de sorption entre deux triazines herbicides et des acides humiques
Authors: GAILLARDON P.
Published: July 2006

La terbutryne est très adsorbée par les acides humiques tandis que l'atrazine l'est peu, cn milieu acide seulement. L'influence du pH sur l'adsorption et l'effet compétitif des cations Ca2+, Al3+ et Fe3+ montrent que la forme protonée des molécules des deux herbicides peut être adsorbée selon un mécanisme du type échange d'ions; la forme neutre des molécules de terbutryne pourrail être adsorbée selon d'autres mécanismes. La désorption de la terbutryne s'accompagne d'un phénomène d'hystéqerésis plus marqué dans le cas des molécules neutres et, en milieu acide, le calcium manifcste un faible pouvoir de déplacement vis‐à‐vis de l'herbicide adsorbé.
Effects of some phenylurea herbicides on photosynthesis of two wheat varieties
Authors: EVELING D. W. , EISA M. Z.
Published: July 2006

A range of plant species was treated with three commercial herbicides to which a cuticule‐damaging kaolin was added. The addition of the kaolin resulted in increased phytotoxicity for Coleus blumei Benth., Phaseolus vulgaris L. and young leaves of Taraxacum offcinale Weber in laboratory and field trials, but failed significantly to increase phytotokicity for twelve common weed species.
A quick method of recording plant growth stages
Authors: KOVÀCS A. I.
Published: July 2006

The recording of the stage of growth of crops and weeds by directly photocopying the plants is described.
Mesure rapide du coefficient de diffusion de l'atrazine en solution aqueuse
Authors: CALVET RAOUL
Published: July 2006

Une méthode est décrite pour la mesure du coefficient de diffusion. Elle est simple à mettre en oeuvre et ne nécessite pas de molécules marquées par un isotope radioactif. Appliquée à l'atrazine en solution aqueuse, elle indique un coefficient d'autodiffusion d'environ 5,6. 10−6 cm2 s−1, légèrement inférieur à celui mentionné dans la littérature.
Spread of weeds from a roadside into sclerophyll forests at Dartmouth, Australia
Authors: Amor R. L. , STEVENS P. L.
Published: July 2006

The extent to which alien plants have spread from an old roadside into three sclerophyll forest communities was measured at a new dam site in Victoria, Australia. The data are discussed in terms of the possible spread of weeds at sites disturbed by the dam construction and subsequent tourist activities.

The frequency of alien plants in the forests declines with increasing distance from the road, and was correlated with the reduction in diffuse light. Wetter communities were more heavily colonized than drier communities.

Rubus procerus P. J. Muell. and Hypochoeris radicata L. were the most successful colonizers. R. procerus, which has become a major weed in the area, was most common near wet sites such as gullies and old water races formerly used for gold mining.
Long‐term effects of herbicides on the photosynthetic apparatus I. Influence of diuron, triazines and pyridazinones
Authors: BÖGER P. , SCHLUE U.
Published: July 2006

Long‐term effects of herbicides on the photosynthetic membrane system were investigated. For this purpose the unicellular alga Bumilleriopsis filiformis was grown in liquid culture in the presence of sublethal concentrations of diuron, atrazine, metribuzin, and some substituted pyridazinones. This allowed reproducible growth conditions, exact dosing of herbicides, and also the preparation of functionally active cell‐free photosynthetic systems.

The electron transport system of cells grown in the presence of ureas and triazine derivatives is not impaired at all, wherea scultivation with pyridazinones damages their photosynthetic redox system. In addition, a strong bleaching effect is observed, whereas the first group of herbicides enhance chlorophyll formation.
An experimental, tractor‐mounted, very low volume uniform‐drop‐size sprayer
Authors: TAYLOR W. A. , MERRITT C. R. , DRINKWATER J. A.
Published: July 2006

The design, construction and performance of an experimental tractor‐mounted machine to apply herbicides to small field plots is described. The machine has five spray units, each with five rotating discs. Uniform sized drops in the range from 150 to 350 μm can be produced with lipophilic, hydrophilic and emulsifiable formulations. Spray volumes can be varied from 5 to 120 1/ha. A preliminary assessment of the physical performance of the machine is presented.
Application of bioassay techniques to herbicide investigations
Authors: HOROWITZ M.
Published: July 2006

Bioassay techniques used in herbicide studies are based on the response of chosen organisms, superior plants or microorganisms, to the chemical. Various means of assessment are used: germination, weight or size of plant parts, modifications in physiological activities such as photosynthesis and transpiration, and typical symptoms. Several special bioassays are described. Dose‐response relations are affected by the age of the indicator plant and environmental conditions of growth. Results can be estimated visually or by objective measurements; for correct interpretation appropriate controls and standards must be included in each experiment. Examples are given of bioassay procedures developed to investigate various aspects of herbicide behaviour: soil effects, dissipation from the soil surface, movement in soil, degradation and persistence.
Factors affecting seedling establishment and survival of Echium plantagineum L., Trifolium subterraneum L. and Lolium rigidum Gaud.
Authors: PIGGIN C.M.
Published: July 2006

Echium plantagineum L. is a widespread, persistent, and often dominant volunteer species in southern Australia. This paper describes glasshouse and field studies investigating its seedling establishment and that of two commonly associated species, Trifolium subterraneum L. and Lolium rigidum Gaud.

In the glasshouse, all species established successfully from sowing depths ranging from 0 to 2.5 cm, and L. rigidum was favoured over the other species when sown on the soil surface (0 cm) and at 7.6cm. In the field, survival of established seedlings during moisture stress was higher for E. plantagineum than T. subterraneum. Seedling‘drought resistance’appeared to be related to rate of root penetration, but not seed size.

Prolific germination after summer and early autumn rains, when temperatures are high, and high seedling survival during moisture stress, explain why E. plantagineum is favoured over T. subterraneum in years with early or‘false’seasonal breaks. T. subterraneum can establish successfully in years with early breaks, but is favoured over E. plantagineum in years with later breaks.
Soil enrichment studies with nitralin
Authors: SIEDSCHLAG E. W. , CAMPER N. D.
Published: July 2006

Soil enrichment studies were conducted with nitralin [4‐(methylsulfonyl)‐2,6‐dinitro‐N,N‐dipropylaniline] with and without exogenous carbon and nitrogen. Bacterial isolates obtained were placed into three categories. Eight fungal isolates, notably Fusarium and Penicillium sp., were obtained from the enriched soil culture. Only one bacterial isolate (Erwinia trachelphila) and no fungal isolates appeared to degrade nitralin. The degradation product isolated was tentatively identified by TLC and radioautography as 4‐(methylsulfonyl)‐2,6‐dinitrophenol. No 14CO2 evolution from ring‐labelled nitralin was detected from any isolates tested.
Interactions between soil‐applied herbicides in the roots of some legume species
Authors: O'DONOVAN J. T. , PRENDEVILLE G. N.
Published: July 2006

The effects on plant growth of applying trifluralin or nitralin combination with simazine, atrazine, prometryne and linuron to the upper 5‐cm root region of vetch (Vicia sativa L.), pea (Pisum sativum L.) and soybean (Glycine max) were investigated. Foliar injury due to herbicides of the second group was markedly reduced in each species by simultaneous treatment with trifluralin or nitralin both of which inhibited lateral root growth without affecting aerial plant growth or tap root extension growth. This inhibition of lateral root growth in roots treated with trifluralin or nitralin was associated with reduced uptake and subsequent transport to the foliage of 14C‐labelled simazine in vetch and pea and 14C‐labelled atrazine in soybean. This probably accounted for the reduction in simazine and atrazine phytotoxicity.

In the presence of trifluralin or nitralin comparatively higher amounts of radioactivity were retained in the roots of pea and soybean and this reduced the amount of 14C available for transport to the foliage. This was not evident in vetch.
Changes in the translocation and distribution of 2, 4, 5‐T in blackberry (Rubus procerus P. J. Muell.) with time
Authors: RICHARDSON R. G.
Published: July 2006

The distribution of 2.4,5‐T in Rubus procerus P. J. Muell. was measured 24 h and 7 days after application to the leaves at 60% of the normal concentration used in the field. There was no significant difference in the amount translocated at these times. At 24 h after treatment there was a very large concentration gradient across the crown but 6 days later the concentration gradient was much smaller. It was concluded that, at the rate used, the amount of 2,4,5‐T translocated to the roots was insufficient to prevent regeneration from the root system.
Weed competition in irrigated cotton (Gossypium barbadense L.) and groundnut (Arachis hypogaea L.) in the Sudan Gezira
Authors: DRENNAN D. S. H. , JENNINGS E. A.
Published: July 2006

Losses of crop yield due to weed competition in unweeded plots averaged nearly 60% of weed‐free yields in cotton and 70% in groundnuts. Weed competition was not directly related to weed groundcover but was dependent on the seasonal growing conditions. The critical period of weed competition in both crops was the 6 weeks between 4 and 10 weeks after crop emergence. During this period cotton could tolerate up to 25% weed groundcover without appreciable loss in crop yield. Groundnuts could tolerate not more than 10% weed cover before yield loss occurred. A main factor in achieving standards of weed control within these limits was preventing the early growth of monocotyledonous weed species: pre‐sowing application of trifluralin and benfiuralin provided this over a wide range of growing conditions.
Control of bracken (Pteridium esculentum G. Forst (Cockayne)) in pasture with asulam
Authors: MARTIN R. J.
Published: July 2006

Asulam was tested for the control of bracken in non‐arable pasture on the North Coast of New South Wales between 1971 and 1976. Satisfactory results were obtained with applications between April and early July, providing treated fronds were mature. The degree of control varied between years and sites. Rates of 4–8 kg a.i./ha reduced frond numbers from 70 to 100% after 6 months but recovery commenced as early as 9–12 months after application. Whole plants and sections of rhizome were excavated 4, 6 and 9 months after treatment and a sequence of events is described for the effect of asulam on bracken. The effects of frond maturity, frond density and frost are discussed in relation to herbicide effectiveness and ecological implications of the results are discussed in relation to increasing productivity of bracken‐infested pasture.
Long‐term effects of herbicides on the photosynthetic apparatus II. Investigations on bentazone inhibition
Authors: BÖGER P. , BEESE B. , MILLER R.
Published: July 2006

Non‐cyclic electron transport by isolated chloroplasts from the alga Bumilleriopsis is inhibited by bentazone, while the activity of photosystem I is not affected. Chloroplast material isolated from cells grown for several days in the presence of bentazone also shows inhibition of photosystem II activity, similar to the decreased cellular photosynthesis. A slow partial recovery is possible, whereas it is fast and complete after exposure of cells or isolated chloroplasts to the herbicide for some hours only. Irreversibility of longterm inhibition could be a metabolic process which brings about the binding of bentazone (or an active derivative) to the thylakoids in vivo, but not in vitro.
The effect of herbicides on respiration and transformation of nitrogen in two soils I. Metribuzin and glyphosate
Authors: MARSH J. A. P. , DAVIES H. A. , GROSSBARD E.
Published: July 2006

The effects of metribuzin and glyphosate at 100 ppm on carbon dioxide evolution and nitrogen transformation in two soils have been investigated in the laboratory. Both herbicides reduced CO2 evolution from Boddington Barn soil (organic carbon content 1.5%, pH 6.6) at some dates, but neither gave any consistent effects on Triangle soil (organic carbon content 4.0%, pH 5.1). Both metribuzin and glyphosate stimulated mineralization of nitrogen for at least 9 weeks. Only metribuzin on Triangle soil gave any indication of inhibition of nitrification. Metribuzin degraded more rapidly in Triangle soil than in Boddington Barn.
Instrumental methods for the analysis of herbicide residues*
Authors: JAKCZYK H. J.
Published: July 2006

Instrumental techniques for the residue analysis of herbicides in soil, water and plant material are reviewed. Various analytical methods, including gas chromatography using different detector systems, thin‐layer chromatography, colorimetry, spectroscopy, as well as the use of labelled compounds for the evaluation of residue methods, are discussed.
Effect of 2,4‐D on the water‐soluble carbohydrate content of ragwort (Senecio jacobaea L.) leaves
Authors: IRVINE A. M. , FORBES J.C. , DRAPER S.R.
Published: July 2006

Leaves of Senecio jacobaea plants sprayed with 2,4‐D had a higher water‐soluble carbohydrate (WSC) content than unsprayed leaves 9–14 days after spraying. Insofar as WSC is a measure of palatability, this implies an increased risk of Senecio poisoning in grazing cattle for more than 14 days after spraying with growth regulator herbicides. Total unsaturated pyrrolizidine alkaloid content may also be increased by 2,4‐D, making the plant more toxic.
The phytotoxicity of various herbicides in two sandy loam soils and the effect of liming
Authors: RICHARDSON W. G. , BANTING J. D.
Published: July 2006

The phytotoxicity of five soil‐acting herbicides was investigated in two sandy loam soils and that of a further five herbicides in one of these soils. The effect of liming on phytotoxicity was also examined. Metoxuron, fenuron, metribuzin and fluometuron were more active in Boddington Barn soil than in Bledington soil. Prometryne was similar in effect in both soils. Liming significantly increased the effect of metoxuron in Boddington Barn soil and metoxuron, atraton, difenoxuron and metribuzin in Bledington soil. Monolinuron was less toxic in limed Bledington soil. Reasons for these differences have not been determined.
Persistence and movement of terbacil in peach orchard soil after repeated annual applications*
Authors: MARRIAGE P. B. , KHAN S. U. , SAIDAK W. J.
Published: July 2006

Terbacil (5‐chloro‐6‐methyl‐3‐butyluracil) residues did not accumulate in peach orchard soil after seven consecutive annual spring applications of the herbicide at the rate of 4.5 kg/ha although carry‐over of terbacil from year to year occurred. Terbacil was lost by degradation and leaching and the time required for a 50% decrease in surface soil concentration was 5–7 months in the sandy loam soil. The major part of the residues was found in the upper 15 cm of the soil profile and smaller amounts were detected to a depth of 60 cm. Terbacil leached readily in prepared columns of sandy loam soil in proportion to the amount of water added. The residual levels of terbacil in the orchard were phytotoxic to oats planted 3 years after the last application.
Chlorfenprop‐methyl: its hydrolysis in vivo and in vitro and a new principle for selective herbicidal action
Authors: FEDTKE CARL , SCHMIDT ROBERT R.
Published: July 2006

Chlorfenprop‐mèthyl is hydrolysed completely as soon as it penetrates the leaf in sensitive as well as in resistant plants. The product of hydrolysis chlorfenprop presumably is the herbicidally active compound. The in vitro hydrolysing activity has been characterized.

The behaviour of the herbicide in a system for the detection of rapid herbicidal activity (leaching system) and in three auxin‐dependent systems leads to the conclusion, that a difference at the site of action is the basis for the observed herbicidal selectivity.
A review of foliar absorption and translocation of 2,4‐D and 2,4,5‐T
Authors: RICHARDSON R. G.
Published: July 2006

This review is restricted to an examination of the literature on the environmental and chemical factors that affect foliar absorption and translocation of 2,4‐dichlorophenoxyacetic acid (2,4‐D) and 2,4,5‐trichloro‐phenoxyacetic acid (2,4,5‐T) by plants. Most of the papers covered by this review have been published since 1965. Earlier works have been reviewed elsewhere by other authors (Currier & Dybing, 1959; Sargent, 1965; Franke, 1967; Robertson & Kirkwood, 1969; Hull, 1970). Often absorption and translocation of herbicides are considered together; here the two will be considered separately wherever possible.
A comparison of the tolerance by winter wheat of herbicide mixtures containing dicamba and 2,3,6‐TBA, or ioxynil
Authors: TOTTMAN D. R.
Published: July 2006

The tolerance by winter wheat of two types of herbicide was examined in field experiments over 3 years. When overdosed or sprayed late, an ioxynil + mecoprop mixture had a greater margin of safety to the crop than mixtures containing dicamba or 2,3,6‐TBA.

Herbicide mixtures containing MCPA, applied before the leaf sheaths of the crop began to extend in the spring caused ear deformities. Spraying dicamba mixtures when the crop was jointing resulted in narrowed ears and shrivelled grain, In one experiment the latter effect was produced by a dicamba mixture, at twice the recommended dose, when sprayed on any of ten dates, covering crop development stages from 6‐leaves through to jointing.

Varieties differed in their tolerance of the dicamba mixtures; Maris Ranger was most sensitive but part of this difference could have been due to differences in the stage of development of the varieties at the time of spraying.
Effects of competition, herbicides and activated carbon on establishment of Australian grasses
Authors: HAGON M. W.
Published: July 2006

The establishment of four Australian native grasses, Themeda australis (R.Br) Stapf, Bothriochloa macra (Steud) S.T. Blake, Danthonia spp. and Stipa bigeniculata Hughes, was investigated in a weedy soil under glasshouse conditions at Canberra, Australia. The presence of weeds (approximately 3500/m2) significantly reduced the percentage emergence of Danthonia and Stipa but had no effect on Themeda, Bothriochloa or the pasture species Lolium perenne L. (ryegrass). The percentage reduction in dry matter production after 8 weeks in the presence of weeds was less for Themeda and Bothriochloa (65%) than for Stipa and ryegrass (80%), while Danthonia production was reduced by over 90% Chlorthal‐dimethyl at 6 or 12 kg/ha reduced the number of emerged seedlings of Danthonia and Stipa but had no effect on emergence of Themeda and Bothriochloa. Diuron at 4 and 16 kg/ha was toxic to seedlings of all four species. The application of activated carbon as a band or a seed pellet overcame the toxic effects of both herbicides, at least at the lower rates of application. The results are discussed in relation to the establishment of native grasses on urban areas requiring low maintenance.
Water utilization by S‐ethyl dipropylthiocarbamate treated wheat
Authors: WILKINSON R. E. , KARUNEN P.
Published: July 2006

Wheat (Triticum aesticum L. var. Holley) was grown in 0.5 Hoaglands complete mineral nutrient solution containing sub‐toxic concentrations of S‐ethyl dipropyl‐thiocarbamate (EPTC) (0, 0.0625, 0.125, 0.25, or 0.5mg/1). Total fresh and dry plant weights per pot decreasedas EPTC concentration increased. Leaf fresh and dry weight per pot decreased as EPTC concentration increased. Root fresh weight per pot was not greatly influenced by EPTC and dry weight per pot was statistically significantly decreased at the 0.5 mg/l EPTC concentration. Total plant water utilization and leaf water contents (mg/g DW) decreased as EPTC concentration increased, but evapotranspiration (ml/g FW or DW) per unit leaf tissue was increased to ca 145% of the untreated wheat. This increased evapotranspiration explains an EPTC induced accumulation of 14C‐atrazine in leaves beyond the detoxification level which ultimately resulted in atrazine injury in EPTC pretreated plants.
Response of spring cereal crops to soil residues of ethofumesate*
Authors: SCHWEIZER E. E.
Published: July 2006

For evaluation of soil residues of ethofumseate [(±)2‐ethoxy‐2,3‐dihydro‐3,3‐dimethylbenzofuran‐5‐yl‐methylsulphonate], spring barley (Hordeum vulgare L.) and spring wheat (Triticum aestivum L.) were sown in soil planted 11 months previously with sugar‐beet (Beta vulgaris L.) and previously treated with band or broad‐cast applications of the herbicide at rates of 1.68‐4.48 kg/ha. The height of barley and wheat was suppressed only where ethofumesate was applied broadcast and the soil was not ploughed after sugar‐beet harvest. Three months after sowing, the 4.48 kg/ha rate suppressed the height of barley 18% and wheat 34%. In another experiment, barley grew normally on soil treated the previous year with pre‐planting and post‐emergence applications of ethofumesate where ploughing followed sugar‐beet harvest. For all treatments, yields of straw and grain were not significantly lower than those of the untreated check plots. The dissipation of ethofumesate 24 weeks after application to sugar‐beet was 89–100% when applied on a band compared to 85‐95% when applied broadcast.
The growth of Arrhenatherum elatius var bulbosum (Willd.) Spenn. in spring barley, as influenced by cultivation
Authors: AYRES P.
Published: July 2006

Populations of Arrhenatherum elatius var bulbosum were established either from seed or vegetatively and studied under four cultivation regimes. Treatments were carried out in the autumn and winter and the experiment was sown with barley in the following spring. Winter mouldboard ploughing gave the greatest reduction of tillers and bulbs of established plants, but was less effective when preceded by rotary cultivation in the early autumn. Tine cultivations increased the numbers of tillers and bulbs, but the largest increase in growth was recorded on plots that were not cultivated.

The germination of seeds was not affected by early autumn cultivations. Mouldboard ploughing, tine cultivation and paraquat at 060 kg a. i. /ha each gave complete control of seedlings in winter.

A simple test on the morphology of plants grown from seed agreed with earlier conclusions that the bulbous form is not a distinct variety. It is suggested, nonetheless, that the bulbous form should be named seperately as in practice it alone succeeds as an arable weed.
Flowering and seed production of Echium plantagineum L.
Authors: PIGGIN C. M.
Published: July 2006

Summary: Résumé: Zusammenfassung

Glasshouse and field studies made in Australia to investigate flowering and seed production of Echium plantagineum L, are described.

Stem elongation and flowering were hastened by long photo‐periods and by tow temperatures. This provides some explanation as to why the species is more common in higher latitudes, where temperatures are low in winter and phoioperiods are long in summer.

The plant produced c. 6000 gcrminable seeds m−2 in a grazed pasture and c. 10 000 germinable seeds m−2 in a nearby ungrazed area. Such productions would be more than adequate to permit persistence and potential dominance. The reduction in seed production by grazing helps to explain why E. plantagineum is often less common in pastures than on ungrazed roadsides and waste areas.

Floraison et production de semences chez Echium plantagineum L.

L'auteur rapporte des essais faits en serre et au champ en Australie pour étudier la floraison et ta production de semences chez Echium plantagineum L.

L'élongation des tiges et la floraison on t été accélérées pa r des photopèriodes longues et par des températures basses, Ceci fournit une explication au fait que cette espèce est plus répandue am latitudes élevées où les températures en hiver soul basses et les photopériodes tongues en été.

La plante produit environ 6 000 sentences viables au m2 dans une prairie pâturée et 10000 semenes viables au m2 dans un environnement non pâturé. De telles productions sont plus que suffisantes pour pertneure la persistance de I'espèce et sa dominance potentielle La rèduction de la production de semences sous l'influence du pâturage aide à expliquer pourquoi E. plantagineum est souvent moins répandue dans les pâtures que le long des routes ou dans les terres incultes.

Blütr und Samenproduktion bei Echium plantagineum L.

Es werden Unitersuchungen zur Blüte und Samenproduktion von Echium plantagineum L. beschrieben. die in Australian mit Hilfe von Gewächshaus‐und Feldversuchen durchgeführt wurden.

Durch lange Photoperioden und niedrige Temperuturen wurde der Stengelzuwachs und dus Blühen beschleunigt. Damit wird erklärlich. warum dicse Art in grösseren Höhen häufiger vorkommt. wo im Winter niedrigce Temperuturen und im Sommer lange Photoperioden hcerrschen.

Die Pflanze produziene auf einer Weide etwa 6000 keimfä‐hige Samen je m2; auf einer in dcer Nähe liegenden unbeweideten Fläche warm es 10000. Eine derartige Samenproduktion ist mehr als ausreichend, um die Persisienz und möglcherweuse auch Jie Dominanz dieser Art zu gevrährleisten. Der Rückgang der Samenproduktion durch Bcweiden macht es erklärlich, warum E. plan tagineum auf Grünland häufig weniger vor‐kommt als auf unbewcideten Strassenrändern und Schuttplatzen.
The influence of temperature and acid scarification duration on Ipomoea obscura Hassk. seed germination
Authors: HARDCASTLE W. S.
Published: July 2006

Summary: Résumé: Zusammenfassung

Germination of seed of Ipomoea obscura Hassk. (small white morning glory) was enhanced when seed coats were pricked with a needle or scarified by cone H2 SO4. When seed were incubated in moist paper towels, they germinated best following 75 min exposure to acid. Seed planted in a potting mixture of sandy clay loam, ground sphagnum moss, and sand germinated best after 90 min in acid. I. obscura seed germination was highest at 15°C, but germination at temperatures up to 35°C was not significantly lower after 144 h incubation.

Influence de la température et de la durée de la scarification acide sur la germination des semences d'Ipomoea obscura Hassk.

La germination des semences d'Ipomoea obscura Hassk. (petit liseron blanc) a été augmentée lorsque l'enveloppe des semences a été piquée avec une aiguille ou scarifiée par l'acide sulfurique concentré. Lorsque les semences ont été mises à germer dans des feuilles de papier spongieux humidifié, la meilleure germination a été obtenue après 75 minutes de traitement acide. Les semences plantées dans un mélange de limon argilo‐sableux, de sphagnum et de sable ont atteint leur meilleure germination après 90 minutes de traitement acide. La germination des semences de /. obscura a été maximale à 15°C, mais la germination à des températures allant jusqu’à 35°C n'a pas été significativement inférieure après 144 heures d'incubation.

Einfluss von Temperatur and Behandlungsdauer mil Söure auf die Keimung der Samen von Ipomoea obscura Hassk.

Die Samenkeimung von Ipomoea obscura Hassk. wurde verbes‐sert, wenn die Samenschale mit einer Nadel angestochen Oder die Samen mit konz. Schwefelsäure behandelt wurden. Wenn die Samen in feuchte Papierhandtücher inkubiert wurden, keimten sie am besten, wenn sie vorher 75 Minuten mit Säure behandelt worden waren. Eine gute Keimung in Topferde, bestehend aus sandigem Lehm, Sphagnum‐Moos und Sand, wurde nach 90‐minütiger Säurebehandlung erzielt. Die Samenkeimung von I. obscura war bei 15°C am besten. Bei einer Inkubationsdauer von 144 Stunden waren die Keimraten bei Temperaturen bis zu 35° C nicht signifikant geringer.
Four season herbicide injection of hardwoods*
Authors: KOSSUTH S. V. , YOUNG J. , VOELLER J. , HOLT H. A.
Published: July 2006

Summary: Résumé: Zusammenfassung

Eleven different hardwood species were injected using a hypo‐hatchet with eight different lierbicides during the spring, summer, fall and winter seasons. Late spring to fall injections gave maximum efficacy. All the herbicides were effective at the given concentrations and injection of I ml/2.5 cm of stem diameter, Least effect followed winter injections probably due to poor translocation, little active tree metabolism, and high viscosity of some formulations when air temperatures were near freezing. Spring injection tended to allow revegetation by release of lateral buds after apical meristems and leaves had been killed. Multiple clumps of red maple stems were not well controlled by single stem injection.

Quatre saisons de traitement herbicide par injection de ligneux à bois dur

Onze espéces ligneuses à bois dur ont été traitées par injection en utilisant une hachette spéciale, avec 8 herbicides, au printemps, en été. en automne et en hiver. Les traitements faits de la fin du printemps à l'automne ont donné le maximum d'efficacité. Tous les herbicides ont été actifs aux concentrations données et pour un volume d'injection de 1 ml pour 2,5 cm de diamétre de tige. L'effet plus faible des injections faites en hiver est probablement du à une faible migration, au métabolisme peu actif dans les arbres et à la viscositéélevée de certaines formulations lorsque les températures de I'air avoisinaient le gel. Les injections de printemps ont montré une tendance à un nouveau départ de la végétation par libération de bourgeons latéraux aprés la mort des méristémes apicaux et des feuilles. De nombreux rejets de tiges d'érable n'ont pas été détruits par une injection unique dans la tige.

Herbizid‐Injektionen bei Laubbdämen in vier Jahreszeiten

Mit Hilfe eines Spezialbeils wurden im Frühjahr, Sommer, Herbst’ und Winter Laubbäumen 11 verschiedener Arten acht

verschiedene Herbizide injiziert. Injektionen vom späten Frühjahr bis zum Herbst zeigten die beste Wirkung. Mit einer Injektion von 1 ml je 2.5 cm Stammdurchmesser waren alle Herbizide in den gewählten Konzentrationen wirkungsvoll. Den geringsten Effekt zeigten Injektionen im Winter, was wahrschein‐ lich auf ungenügende Translokation, geringe Stoffwechselaktivität der Bäume im Winter und hohe Viskosität einiger Formulierungen bei Lufttemperaturen in der Nähe des Gefrierpunktes zurückzuführen ist. Injektionen im Frühjajr konnten nach Abtötung von apikalen Meristemen und Blattwerk durch Entwieklung von Seitenknospen zu einem gewissen Austrieb führen. Baumgruppen von Rotahorn liessen sich durch eine einzelne Stamminjektion mit nur mässigem Erfolg bekämpfen.
The inactivation of glyphosate by various soils and metal salts*
Authors: HENSLEY D. L. , BEUERMAN D. S. N. , CARPENTER P.L.
Published: July 2006

Summary: Résumé: Zusammenfassung

A root bioassay was used to determine the effect of various soils, and the chloride salts of Fe+++, Fe++, Al +++, Ca ++, K +, and Na+ on the activity of glyphosate (N‐(phosphonomethyl)glycine]. Mineral soils significantly reduced the inhibitory effects of glyphosate on root growth. One muck soil inactivated glyphosate, but another muck soil and bentonite clay had little effect. Soils with the greatest inactivation capabilities had high concentrations of weak‐acid‐extractable iron. Glyphosate inactivation showed no correlation between cation exchange capacity and organic matter of the muck soils. FeCl3, FeCl2 and AlCl3, significantly reduced the activity of glyphosate, and, when allowed to stand in solution, combinations of FeCl3 and glyphosate formed a precipitate. CaCl2, KCl and NaCl did not inactivate glyphosate.

Inactivation du glyphosate par divers sols et sels métalliques

Un test biologique sur racines a été utilisé pour déterminer l'action de divers sols et de sels chlorés de Fe+++, Fe++, Al++, Ca++, K +, et Na+ sur I'activité du glyphosate N‐(phosphono‐méthyl) glycine. Les sols minéraux ont réduit significativement les effets inhibiteurs du glyphosate sur la croissance des racines. Un sol organique a inactivé le glyphosate, mais un autre sol organique, ainsi que la bentonite. n'ont eu que peu d'effet. Les sols qui ont présenté les plus grandes possibilités d'inactivation renfermaient des concentrations élevées dc fcr extractible par des acides faibles. II n'a pas été observé, en ce qui concerne l'inactivation du glyphosate, de corrélation entre la capaeité d'échange des cations et la teneure matiére organique des sols organiques. FeCl3, FeCl2, et AlCl3 ont significativement réduit l'activité du glyphosate et, lorsqu'ils ont été mis en présenceen solution, la combinaison de FeCl3 et du glyphosate a provoqué la formation d'un précipité, CaCl2, KCl et NaCl n'ont pas inactivé le glyphosate.

Die Inaktivierung von Glyphosat durch verschiedene Böden und Metallsalze

Die Wirkung verschiedener Bödden und der Chloride von Fe+++, Fe++, Al+++, Ca++, K+ und Na+ auf die Aktivität von Glyphosat N‐(Phosphonomethyl)glycin wurde mit einem Wurzel‐Biotest festgestellt. Mineralische Böden verringerten signifkant den Hemmeffekt von Glyphosat auf das Wurzelwachstum. Durch einen der organischen Böden wurde Glyphoat inaktiviert, ein anderer und das Tonmineral Bentonit, wirkten jedoch nur wenig inaktivierend. Böden mit der stärksten Inaktivierungsfähigkeit besassen hohe Konzentrationen an mit schwacher Säure extrahierbarem Eisen. Die Inaktivierung von Glyphosat war nicht mil der Kationen‐Austauschkapazität und dem Gehalt der Böden an organischer Substanz korreliert Durch FeCl3, FeCl2 und AlCl3 wurde die Aktivitat von Glyphosat signifikant verringert. Wenn FeCl3 und Glyphosat in Lösung zusammengebracht wurden, bildete sich beim Stehenlassen dieser Kombination ein Niederschlag. CaCl2, KCl und NaCl wirkten auf Glyphosat nicht inaktivierend.
Computed effect of decomposition on the partition coefficient determined by the batch equilibration method
Authors: DEKKERS W. A.
Published: July 2006

Summary: Résumé: Zusammenfassung

A simulation model was used to calculate the effect of decomposition on the soil‐water partition coefficient of a herbicide determined by a batch equilibrium method.

The results showed the necessity of a correction for decomposition in calculating the equilibrium partition coefficient, especially during repeated desorption steps, even if the amount decomposed was very small.

Estimation de l'effet de la déecomposition sur le coefficient de partage déterminé par la méthode de équilibres dans des suspensions

Un modèle de simulation a été utilisé pour calculer l'effet de la décomposition d'un herbicide sur son coefficient de partage sol‐eau, en déterminant les équilibres dans des suspensions. Les résultats ont montré la nécessité d'une correction pour la décomposition, dans le calcul du coefficient de partage en équilibre, particulièrement durant les étapes de la désorption, et même dans le cas oò les quantités décomposées ont été très faibles.

Einfluss des Abbaus auf den Verteilungskoeffizienten‐Bestim‐mung nach der “batch‐equilibration”—Methode

Der Einfluss des Abbaus auf die Bestimmung des Boden/Wasser‐Verteilungs koeffizienten eines Herbizids mit der “batch‐equilibration”—Methode wurde mit einem Simulationsmodell erforscht. Die Ergebnisse ergaben, dass für die Berechnung des Verteilungskoeffizienten eine Korrektur eingeführt werden muss, die dem Abbau Rechnung trägt. Das gilt besonders für wiederholte Desorptionsschritte, auch wenn dabei die abgebaute Menge sehr klein ist.
Etude sous conditions contrôlées de la concurrence entre le chénopode blanc (Chenopodium album (L.)) et la variété de maïs INR A 258, en fonction du stade de développement du chénopode
Authors: CAUSSANEL J. P.
Published: July 2006

Summary: Résumé: Zusammenfassung

Dans Jes conditions contrôlées d'une salle climatisée, la concurrence entre le chénopode blanc (Chentopdium album) et de jeunes plantules de maïs (variété INRA 258) a éléétudiée en fonetion du stade de développcment du chénopode. sur sol et sur solution nutritive, Des eftets depressifs croissants du cbénopode sur e maïs en fonction du stade de développement atteint par le chénopode au début de chuque essai ont élé mis en évidence: ceseffets sont plus précoces sur solution nutritive que sur sol. II csi suggéré que des effets non compétitifs peuvent contribucr à la concurrence exercée par le chénopode blane sur le maïs.

Study under controlled conditions of the competition between Chcnopodium album (L.) I and the rariety of maize INRA 258 in relation to the stage of development of Chcnopodium album

In the controlled conditions of a growth chamber, the competition between Chenopodium album and young plants of maize (variety INRA 258) was studied, in relation to the stage of development of C. album in soil and in nutrient solution Increasing depressive effects on the maize in relation to the stage of development of C. album at the start of each test were noted earlier These effects were shown in nutrient solutions rather than in soil. It is suggested that non‐competitive effects can contribute to the influence exercised by C. album on the maize

Untersuchungen zur Konkurrcnzwirkung von Chenopodium album (L.) auf die Maissorte INRA 258 unter Kontrollierten Bedingungen in Zusamenhang mit dem Entwickhungsstadium ran Chenopodium album

Es wurden Untersuchungen zur Konkurrenz zwischen Chenopodium album und jungen Maispflanzen (Sorte INRA 25K) in Klimakammern durchgeführL Die Pflanzen wuchsen in Nährlösung bzw. im Bo den Das Ziel der Untersuchungen war, den Einfluss des Entwicklungsstadiums von C. album festzustellen. Mit zunehmendem Entwicklungssiadium der C. album PManzen wurde der Mais deutlich stärker untcrdruckt Diese lilfckte waren in Nährlösung Prüher ausgeprägt als im Boden. Is wird angenommen. dass cinige nicht auf einer Konkurrcnzwirkung beruhenden Effekte zum Einfluss von C. Album auf Mais beitragen können
Competitive growth of Echium plantagineum L. and Trifolium subterraneum L.
Authors: PIGGIN C. M.
Published: July 2006

Echium plantagmeum is a widespread, persistent, and often dominant votunteer species in southern Australia. In pastures. it commonly grows with Trifolium subterraneion. This paper describes glasshouse studies investigating the effects of soil fertility. plant density. sward composition, defoliation frequency. and delayed estabilishment of t. subserraneum on the growth of E. pluntagineum and T. subterraneum when grown in pure swards and in mixtures.

Generally. herbage production of swards was increased by the presence of E. plantagineum. the addition of nutrogen and phosphorus fertilizers, and increasing density, It was decreased by defoliation. E. pluntagineum plants generally produced more shoots and roots than did T. subterraneum. Both species responded. E. plantiagineum generally more than T. subterraneum. to added phosphorus and nitrogen fertilizers. Both species showed a non‐linear reduction in plant size as plant density of the sward was increased. especially during early growth. E. plantagineum was, however. more plastic in its response to density than T. subterraneum. Defoliation reduced the plant weight of both species. more for E. plantagineum than for T. subterraneum.

In mixtures. there was little competition between the two species during early growth. when swards were defoliated and when both species established at the same time. T. subserraneum was, howerver. sometimes suppressed during later growth if swards were undefoliated. if soil fertility was high. and if E. plantaginteum established before t. subserraneum. Such competition appeared to be between shoots rather than between roots.

In the field. E. plantagineum is likely to be fovoured in undergrazed situations, where soil fertility is high and when false or early seasonal breaks allow it to establish earlier than t. subterruneum. Its high productivity under a wide range of pasture situations ‐ especially in autumn and winter when pasture availability is ofter critically low and the fact that it is relatively nutritious and readily eated by stock suggest that it is a useful pasture species.
La detection et le dosage des herbicides à l'aide des chlorelles: recherches sur les conditions expérimentales optimales et application à l'analyse de plusieurs herbicides
Authors: LEFEBVRE‐DROUET E. , CALVET R.
Published: July 2006

The detection and estimatinn of herbicidés uith ihe aid of Chtorelta: investigation of optimum conditions and iheir applicalion to the analysis of several herbicides

The use of a uniform culture of Chlorella as yn inoculum at a given density under known conditions of temperature, light and nutrition in a gaseous mixture has allowed an improvement in the technique and given highly reproducible results. Tests with atrazine have shown that it can be detected at a dose or 0.012 ppm and estimated to an accuracy of 0.04 ppm. Other herbicides have been tested and their sensitivity was found to be in lhe following descending order: lerbutryne > lenacil = isoproturon > atrazine > chlortoluron > methabenzthiazuron = metoxuron.
The effect of herbicides on respiration and transformation of nitrogen in two soils III. Lenacil, terbacil, chlorthiamid and 2,4,5‐T
Authors: MARSH J.A.P. , DAVIES H.A.
Published: July 2006

The effects of lenacil, terbacil, chlorthiamid and 2,4,5‐T at 100 ppm on carbon dioxide evolution, oxygen uptake and nitrogen transformation in two soils have been investigated for several months in the laboratory. The herbicides had no effect on CO2 output from either Boddington Barn soil (organic carbon content 1.6%, pH 6.1) or Triangle soil (organic carbon content 3.7%, pH 4.8) apart from 2,4,5‐T which reduced it sometimes. All the herbicides caused temporary reductions in O2. uptake, but in Triangle soil treated with 2,4,5‐T a significant reduction was observed during the second half of the incubation. 2,4,5‐T and to a lesser extent chlorthiamid, reduced nitrification in Triangle soil. All the herbicides slightly increased mineralization of nitrogen except 2,4,5‐T which had variable effects in Triangle soil.
Effect herbicides on weed control, yield and quality of eggplant (Solanum melongena L.) in Trinidad
Authors: BRATHWAITE R. A. I.
Published: July 2006

Summary: Résumé: Zusammenfassung

The effects of six herbicides on weed control, yield and quality of transplanted.‘Early Long Purple’eggplant (Solantam melongena L.,) were evaluated in two replicated field experiments during the wet seasons (June to December) of 1976 and 1977 on River Estate loam soil in trifluralin 0 kg and had gave the best yield and excellent weed control for 8 weeks. Benfluralin (kg and ha) isopropalin (1.5 kg m.a ha) and diphenamid (5.0 kg and ha) gave acceptable weed control for 8 weeks and satisfactory yields, but chlorthal‐dimethyl (1 kg a ha) and hotra (40 kg a ha) were less satisfactory. All the herbicides tested controlled weed for 4 weeks. There was no crop injury.

Effet des herbicides sur le desherbage de sendement et la qualite de l'aubergine (Solanum melongena L.,) d Trinidad

Les effets de herbicides sur le desherbage, le rendement et la qualite de preds transplantes d'aubergine (Solantum melongena L.,) var ‘Farly Long Purple’, ont ete evalues dans deux experiences au champ, durant les sarsons humides (june to December repetees en 1976 et 1977, sur un sol argileux de River Estate a Trinidad La triflurraline 1.0 kg m a has donne le meilleut rendement et un excellent desherbage pendant S sernames I a benfluraline (1.1 kg m.a. ha) l'isopropaline (1.5kg ma. Ha) et le diphenamide (5.0 kg m.a ba) ont donne un desherbage acceptable et des rendements satisfaisant mais le chlorthal dimethyl (10.0 kg m.a ha) et la butraline (4.0 kg m.a ha) ont ete moins satisfaisants Tous les herbicides essayes ont maitrise les measures herbes pendant 4 semaines II n'y a pas eu de degats sur la recolte.

Emsatz von Herbizalen in Eterfruchen Solanum melongena in Trinidad Wirkane aut Unkraut. Ertrag und Qualdat.

Es wurde die Ergnung von wchs Herniziden fur die Unkraut‐bekämpfung in gepfltanzten Eterfrüchten (Solaman melongena L.) der Sorte ‘Early Long Purple’ sowie the Wirkung aut Ertrag und Qualität in zwer Feldversuchen wahrend der Regen zen (Juni bis December) in den Jahren 1976 und 1977 auf einem River‐Estate‐Lehmnoden in Trinidad gepruit. Mit Trifluralin (1.0 kg ha AS) wurden die hochsten Ertage und cine ausgezetchnete Unkrauthekämpfung über acht Wechen erzielt Benfluralin (1.1 kh ha AS) Isopropalin (1.5 kg ha AS) und Dephenamid (5.0 kg ha AS) wirkten uber acht Wochen zufriedenstellend und führlen zu mittleren Ertagen; Chlorthaldimethyl (10.0 kg ha AS) und Butralin (4.0 kg ha AS) befriedigten weniger. Alle gepruften Herbicide bekämpften die Unkrauter uber cine Zeit von 4 Wochen. Schaden an der Kulturpflanze konnten nicht festgestellt werden.
Studies on the depth distribution and on the germination and growth of Equisetum arvense L (field horsetail) from tubers
Authors: WILLIAMS E.D.
Published: July 2006

Soil core samples taken from a sandy loam soil at Woburn during January 1972, following spring beans during the previous year, indicated that half the rhizome dry weight of Equisetum arvense (L.) occurred in the uppermost 25 cm of soil and 10% between 75 and 100 cm. Tubers occurred relatively more deeply with half the number and three‐quarters of the weight deeper than 50 cm. However, after a 2‐year fallow 80% of the rhizomes and tubers were in the uppermost 25 cm of soil. In general, the weight of individual tubers increased with increasing depth in the soil. In pots in the glasshouse, tubers that were formed in one season lost weight when new shoots emerged in the following year; those formed during summer germinated readily in warmth indoors when detached in the autumn, but not until June of the following year in the field. Burial of tubers at a range of depths down to 25 cm did not affect the number of shoots emerging but emergence was delayed.

Plants made more growth in neutral than in acid or basic soil, more in silty clay loam than in sandy loam and appeared well adapted to growth in soils with little nitrogen. In general, rhizome growth was less affected by variations in pH and nitrogen level than were shoots and tubers. Plants grown from tubers were suppressed greatly by wheat sown densely and given a moderate amount of nitrogen fertilizer but had negligible effect on the wheat. With fewer wheat plants given less nitrogen, the species partitioned more of its assimilate into tubers than when it was grown alone.

The significance of tubers in the biology of the species is briefly discussed and areas meriting further study are highlighted.