bluuebunny/crossref_metadata_2025_split huggingface dataset:
Persistence and movement of ethofumesate in soil*
Authors: SCHWEIZER E. E. 
Published: July 2006

Summary:Persistence of ethofumesate [(±)2‐ethoxy‐2.3‐dihydro‐3,3‐dimethylbenzofuran‐5‐yl‐methansulphonate] in soil was associated with soil temperature. Ethofumesate applied at 4.5 kg/ha in November persisted about twice as long in soil as that applied the following March. In another field study, 88–91% of the herbicide had dissipated after 24 weeks in sandy loam soil, compared to 72–77% in loam soil when it was applied at rates of 2.2, 3.4, 4.5, and 9.0 kg/ha. The rate of degradation was independent of the initial rate of chemical applied. The time required for 50% of the herbicide to dissipate in sandy loam and loam soils was 7.7 and 12.6 weeks, respectively. The movement of ethofumesate in these two soils over a 24‐weeks sampling period was confined mainly to the upper 7.5 cm of the soil profile.
Adsorption et désorption de la pyrazone par quelques colloïdes organiques et minréaux
Authors: FUSI P. , CECCONI S. , Franci M. , VAZZANA C. 
Published: July 2006

Résumé:On a éludié l'adsorption et la désorption de la pyrazone sur des colloïdes organiques et minéraux et sur des résines échangeuses d'ions saturées par les ions H+, Na+, K+, Ca++ et Mg++. Pour ce qui concerne les adsorbants‐H, on a trouvé l'ordre d'adsorption suivant: Amberlite‐H> Dowex‐H > humus‐H> montmorillonite‐Al,H > illite‐Al,H > kaolinite‐ Al,H. Cette adsorption, qui semble etre due à des liaisons physiques et non à des mécanismes de protonation, est plus grande que celle trouvée avec des systèmes‐K, ‐Na, ‐Ca, et ‐Mg. Avec des systèmes‐Ca on a obtenu le même ordre d'adsorption: Dowex‐Ca> montmorillonite‐Ca> illite‐ Ca> kaolinite‐Ca. Contrairement à ce que nous avons trouvé pour la résine Dowex, avec la montmorillonite et l'illite, le cation saturant semble avoir un effet sur l'adsorption de la pyrazone; en effet nous avons obtenu l'ordre suivant: Ca++> Mg++> K+> Na+. Pour tons les systèmes que nous avons examinés, la désorption de la pyrazone adsorbée a été complète.
Specific microbial responses to herbicides*
Authors: GROSSBARD ERNA , DAVIES HAZEL A. 
Published: July 2006

Summary:Examples from the literature and from the authors’own laboratory demonstrate that herbicides can exert adverse effects on the soil micro‐flora, depending on concentration, though often at higher rates than the herbicidal dose. Examples refer to changes in microbial growth (asulam, linuron, paraquat) and equilibrium (metoxuron), respiration and nitrification in samples from field experiments (linuron, simazine) and laboratory experiments (bentazone, glyphosate, barban, etc.), enzyme activities (urease, phosphatase; barban, chlorpropham, linuron) and the decay of sprayed vegetation (glyphosate, paraquat).
A note on the dispersal of seeds of blackberry (Rubus procerus P.J. Muell.) by foxes and emus
Authors: BRUNNER H. , HARRIS R. V. , AMOR R. L. 
Published: July 2006

Summary:The monthly variation in the number of seeds of blackberry (Rubus procerus P. J. Muell.) in fox (Vulpes vulpes) faecal droppings was measured at two sites in Victoria, Australia. The maximum percentage of droppings containing seeds (89% at Dartmouth and 55% at Sherbrooke) and the maximum monthly average for the number of seeds per dropping (570 at Dartmouth and 390 at Sherbrooke) occurred in March. Droppings of emu (Dromaius novaehollandiae) collected at Dartmouth contained a mean of 2460 blackberry seeds per dropping.Blackberry seed obtained from berries, fox droppings and emu droppings was tested for germination over a 1O‐month period. Germination commenced in spring and ranged from 22 to 35%.It is concluded that foxes and birds are probably responsible for dispersing blackberry over large areas of Victorian bushland.
Uptake, translocation, metabolism and selectivity of glyphosate in Canada thistle and leafy spurge
Authors: GOTTRUP O. , O'SULLIVAN P. A. , SCHRAA R. J. , VANDEN W. H. 
Published: July 2006

Summary:The uptake, translocation and metabolism of glyphosate [N‐(phosphonomethyl) glycine] by Canada thistle (Cirsium arvense (L.) Scop.) (susceptible) and leafy spurge (Euphorbia esula (L.)) (resistant) were examined in an attempt to elucidate the nature of the differential sensitivity. The pattern of uptake and translocation was similar in both species. Glyphosate moved readily in the apoplast and the symplast. High humidity and/or surfactant greatly increased the amount of 14C‐glyphosate absorbed and translocated over that in low humidity and/or without surfactant. No 14Cmetabolites were detected in either species 1 week after treatment with 14C‐glyphosate. More of a glyphosate spray solution containing a fluorescent dye was received and retained on Canada thistle by virtue of its growth habit than on leafy spurge. More glyphosate should therefore be available for uptake by Canada thistle and this may account for the differential sensitivity of these two species.
The vegetation of roadsides and adjacent farmland of the Mornington Peninsula, Victoria, Australia
Authors: LANE D. 
Published: July 2006

Summary:A survey of the composition and structure of the vegetation of the roadside easement and adjacent farmland was made at eighteen sites on the Mornington Peninsula. Victoria, Australia. The ground cover was grass dominant at all sites, with a predominance of introduced species notably Holcus lanatus, Anthoxanthum odoratum and Briza maxima. Agrostis tenuis and Paspalum dilatatum occurred to a lesser extent. Two alien broad‐leafed species, Hypochoeris radicata and Plantago lanceolata, were abundant at most sites.The frequency of species present on the easement was markedly reduced in the adjacent farmland; conversely, the pasture plants Lolium perenne, Trifolium repens and T. subterraneum, did not colonize the easement to any great extent.At some sites, the native trees and shrubs had not been cleared during road construction. They were able to survive on the easement despite the influences of the adjacent road and farmland. Seedlings of all the native species were found.
Investigations into some aspects of the biology of potatoes as weeds
Authors: LUTMAN P. J. W. 
Published: July 2006

Summary:The results of a survey of potato fields have shown that up to 370 000 tubers/ha may remain in the field after the potato harvest. Most of these tubers were less than 4 cm in diameter and their distribution in the soil suggests that they had fallen between the bars of the harvester elevators.Despite high mortality during winter, substantial populations of potato plants were found in subsequent crops. Up to 50 000 sprouts/ha were recorded in a survey of several winter wheat fields. Emergence of these sprouts started in April and continued until the end of May, and in other trials new sprouts were still emerging at the end of June. Several experiments indicated that soil temperatures and moisture levels in spring and also tuber depth affected emergence; the deeper tubers emerged later. Weed potato plants in cereal crops were found to produce an average of 2 daughter tubers, thus providing a tuber population for infestations in the following year.The results are compared with those of other workers, and their importance in the development of methods of control is discussed.
Glasshouse trials with controlled drop application of some foliage‐applied herbicides
Authors: MERRITT C. R. , TAYLOR W. A. 
Published: July 2006

Summary:MCPA, mecoprop, dichlorprop, dicamba, 2,3,6‐TBA, bentazone, ioxynil/bromoxynil (a mixture), barban, difenzoquat and chlorfenprop‐methyl were applied by spinning disc in controlled drop sizes from 150‐350μm and at very low volume rates (5–45 1/ha), to the foliage of some dicotyledonous weed species or wild oats (Avena fatua L.). The same herbicides were also applied by means of conventional hydraulic nozzles at volume rates of about 200 1/ha. Most of these herbicides performed as well at very low volume rates as with the conventional application, the major exceptions being bentazone, ioxynil/bromoxynil (both of which have distinct contact effects) and dichlorprop. Comparisons between oil and water as the diluent at a very low volume rates suggest that there may be situations when oil is preferable and others when water is.
The degradation of simazine, linuron and propyzamide in different soils
Authors: WALKER A. , THOMPSON JULIE A. 
Published: July 2006

Summary:Simazine, linuron and propyzamide were incubated in 18 different soils at 25°C and field capacity soil moisture content. The degradation of each herbicide followed first‐order kinetics. The half‐life of simazine varied from 20 to 44 days, that of linuron from 22 to 86 days and that of propyzamide from 10 to 32 days. The rate of linuron degradation was highly significantly correlated with soil organic matter content, clay content, soil respiration and the extent of herbicide adsorption by the soil. The rate of simazine degradation was significantly and negatively correlated with soil pH, but the rate of propyzamide degradation was not related with any of the soil factors examined.
Seed dormancy and periodicity of seedling emergence in Veronica hederifolia L.
Authors: ROBERTS H.A. , LOCKETT PATRICIA M. 
Published: July 2006

Summary:Emergence of Veronica hederifolia seedlings began in mid‐October and continued into spring; few appeared from June to September. Ripe seeds shed in June were dormant but wben buried in soil outdoors developed a capacity for germination initially at low temperatures (constant4 C; daily alternations of 4‐10° and 4‐1 5 C) and later at somewhat higher temperatures, with peak germination in September‐November. During winter, spring and early summer thc germination capacity declined, to increase again in late summer and early autumn. Cyclic physiological changes thus occur in seeds of V,hederifolia present in the soil, with which lhe consistent seasonal periodicity of seedling emergence is associated.In dry storage ihe capacity for germination progressively increased, but alter 12 months there was a sharp decline in germination at 4° C. Few seeds germinated at 20° C, but moistening with GA 4/7; brought about complete germination at this temperature.
Impact of 2,4‐D on Ceuthorhynchidius horridus (Coleoptera: Curculionidae) and their compatibility for integrated control of Carduus thistles
Authors: TRUMBLE J. T. , KOK L. T. 
Published: July 2006

Summary:Acute and chronic effects of spring application of 2,4‐D on adult C. horridus (Panzer) were examined by determining dose‐mortality response and adult vitality. LC50 values for males (70.2 kg/ha) and females (61.4 kg/ha) corresponded to 41.7 and 36.6 times, respectively, the recommended application rate of 1.68 kg/ha. Survival of weevils treated with 1.68 kg/ha was not different from untreated controls, but higher doses (16.8–147.8 kg/ha) caused significantly greater mortality. Adult vitality, measured by number of feeding marks per weevil and rate of weight change. was unaffected by the herbicide. When thistle infested fields were sprayed with 1.68 or 2.24 kg/ha of 2,4‐D the host plants died, but the survival, reproduction, and population increase of C. horridus were not affected.
A study of competition between seedlings of gorse (Ulex europaeus L.) and perennial ryegrass (Lolium perenne L.) by means of a replacement series experiment
Authors: IVENS G. W. , MLOWE F. 
Published: July 2006

Summary:Competiton between seedlings of gorse (Ulex europaeus L.) and perennial ryegrass (Lolium perenne L cv. Grasslands Nui) was studied in a replacement series experiment under glasshouse conditions. Without cutting, the shoot growth of gorse in monoculture exceeded that of ryegrass over 22 weeks but was reduced more by competition from ryegrass than the grass growth was reduced by competition from gorse. The root system of gorse was small compared with that of ryegrass and was further reduced by competition. Cutting three times at 2 or 4 cm reduced the total growth of both species and gorse was affected more than ryegrass. With grass, however, the ‘growth between succeeding cuts declined faster than that of gorse and in the final harvest period, gorse in monoculture oulyielded ryegrass. The relative crowding coefficients of gorse were low compared with those of ryegrass and their products consistently exceeded 1.0. The results are discussed in relation to lirmiting seedling establishment of gorse in the field.
Interaction between glyphosate and various herbicides for broadleaved weed control
Authors: O'SULLIVAN P.A. , O'DONOVAN J.T. 
Published: July 2006

Summary:The effects of several herbicides for broadleaved weed control on glyphosate (n‐phosphonomethyl glycine) phytotoxicity to wheat (Triticum aestivum L.), barley (Hordeum vulgare L.) and wild oats (Avena fatua L.) were studied in the greenhouse. In tank mixtures, dicamba (3,6‐dichloro‐o‐anisic acid), 2,4‐D (2,4‐dichlorophenoxy‐acetic acid) and bromoxynil (3,5‐dibromo‐4‐hydroxy benzonitrile) reduced the phytotoxicity of threshold rates of glyphosate on all three species. With increasing rates of the herbicides for broadleaved weed control relative to a fixed rate of glyphosate, there was a general trend towards increased antagonism. Increasing glyphosate rates above the threshold level in mixtures containing a fixed rate of herbicides for broadleaved weed control overcame the antagonism. Both the inert and active ingredients of 2,4‐D amine and ester appeared to be involved in the antagonism. There was no reduction in glyphosate phytotoxicity on the annual grasses when 2,4‐D or bromoxynil were sprayed sequentially at various times in relation to glyphosate. When droplets of bromoxynil and glyphosate were placed side by side on a leaf, glyphosate phytotoxicity was not reduced, whereas when the two herbicides were mixed and applied as one droplet, considerable reduction in glyphosate phytotoxicity occurred. These results suggest that the reduction in glyphosate phytotoxicity caused by tank mixing with herbicides such as 2,4‐D, bromoxynil and dicamba may be due to a physical or chemical incompatability within the tank mixture rather than to a biological interaction in the plant.
Residues of atrazine and its metabolites after prolonged usage
Authors: KHAN S. U. , SAIDAK W. J. 
Published: July 2006

Zusammenfassung:Atrazine was applied to a field planted to corn (Zea mays L.) for 20 consecutive years at rates ranging from 1.40 to 2.24 kg/ha. Analysis of soil samples taken 6 and 12 months after the final application showed the presence of residues of the parent compound and its mono dealkylated hydroxy analogues. Shoots and roots of oat (Avena saliva L.) plants grown in the field contained hydroxyatrazine (2‐hydroxy‐4‐ethylamino‐6‐isopropylamino‐s‐triazine) and one of its mono dealkylated analogues in the conjugated form. Oats and timothy (Phleum pralense L.) grown in treated soil in a growth cabinet showed similar results. The data suggest that long‐term annual applications of atrazine for weed control in corn result in the persistence of some of its degradation products, mainly hydroxylated analogues, in soil I year after the final herbicide application. It is conceivable that such residues may enter into the food crops planted in atrazine‐treated soil in the year or years following the cessation of a long‐term treatment.
The kinetics of linuron and metribuzin decomposition in soil using different laboratory systems
Authors: HANCE R.J. , HAYNES R. A. 
Published: July 2006

Summary:Rales of linuron and metrihuzin breakdown in soil were studied in four laboratory systems: fresh soil incubated in polyethylene bags; air‐dry soil resetted and incubated in polyethylene bags; complete soil cores; a perfusion apparatus. The apparent order of reaction. estimated using a power rate equation, varied from 0.45 to 2.90 and was not consistent with respect either to the compounds or the incubation methods. It is possible that diffusion controlled processes may be involved in producing this variation. The results of six of the eight experiments could be fitted to the first order rate equation (P= 0.01). When the first order model was statistically valid, half‐life times were within 50% of the time for 50% disappearance calculated wiih the power rate expression but there were differences up to five‐fold in the times for 90% disappearance, calculated by the two methods. It is suggested that decomposition experiments giving orders of reaction greater than I require verification in more than one experimental system
Ash from rice stubble inactivates thiobencarb and molinate
Authors: TOTH J. , MILHAM P. J. , RAISON J. M. 
Published: July 2006

Summary:The vegetative growth of Japanese millet (Echinochloa utilis Ohwi et Yabuno) was much lens reduced by pre‐emergent treatments of thiobencarb (S‐eithyl hexahydro‐1,4‐azepine‐l‐thiolcarbamate) and molinate (S‐(4‐chlorobenzyl)‐N.N‐diethylithiolcarbamate] when the herbicides were applied at <4 l a.i. ha−1 over rice stubble ash. The effcct was caused by adsorption of the herbicides onto activated carbon in the ash and occurred alike in field and pot experiments.The reduction in herbicide activity was quantified in the pot experiment. There the ash rendered at least 60% of the applied herbicide biologically unavailable.
Maternal inheritance of simazine resistance in a population of Senecio vulgaris
Authors: SCOTT K. R. , PUTWAIN P. D. 
Published: July 2006

Summary:Inheritance of resistance to simazine was investigated in reciprocal pair crosses of resistant and susceptible genotypes of Senecio vulgaris. The simazine resistant genotypes had been selected in a screening experiment and were unaffected by 2.8 kg ha−1˜’a.i. simazine. Reciprocal differences for resistance and susceptibility to simazine in F2 families showed that resistance is maternally inherited. The practical implication of maternal inheritance is that a resistant field population will build up very rapidly from a very low initial frequency of the resistant genotype.
Selective herbicides for establishing weed‐free grass. I. Evaluation of ethofumesate and methabenzthiazuron
Authors: HAGGAR R. J. , KIRKHAM F. W. 
Published: July 2006

Summary:The consequences of using two pre‐emergence herbicides on autumn‐sown perennial ryegrass (Lolium perenne L.) were measured over 3 years in a field experiment. Ethofumesate (2‐ethoxy‐2,3‐dihydro‐3,3‐dimethylbenzofuran‐5‐yl melhylsul‐phonate) and methabenzthiazuron [N‐(benzothiazol‐2‐yl)‐N, N'‐dimethylurea] were each applied at 0, 0.8, 1.6 and 3.2 kg ha−1 one week after drilling the grass seed. Monthly counts of plants per unit area and tillers per plant were made until the following April and the herbage dry weights of the major species were recorded at seven harvests.Heavy infestations of Stellaria media (L.) Vill. and Poa annua L. occurred on untreated plots. Ethofumesate, and to a lesser extent methabenzthiazuron, proved effective in suppressing these weeds, only low rates being needed to control S. media. Both weeds needed to be controlled to achieve full benefits to the crop; control resulted in a 4‐fold increase in ryegrass tiller density by the first spring and a 6‐fold increase in ryegrass herbage was recorded at the first harvest in May. Some yield benefits were carried over into the second year but not into the third. In total, an extra 4.16 t ha−1 of ryegrass dry‐matter was harvested from plots treated with ethofurnesate at 0.8 kg ha−1 compared with the controls. The results are discussed in terms of defining optimum crop densities when pre‐emergence herbicides are used.
Action of propanil on in vivo chlorophyll a fluorescence in Echinochloa crus‐galli and rice
Authors: DANIELL H. , SAROJINI G. , KUMARACHINNAYAN P. , KULANDAIVELU G. 
Published: July 2006

Summary:When sprayed as a post‐emergent, foliar herbicide propanil destroyed Echinochloa crus‐galli (L.) with little or no visible injury to rice, confirming its selective contact action. In treated rice leaves there was, however, a temporary decrease in dry weight, pigments, proteins and photosynthetic products followed by complete recovery in 4–5 days. In both rice and E. crus‐galli, at lower concentrations propanil inhibited the electron flow in a manner similar to that of DCMU, but at higher concentrations it damaged the primary electron donor. In vivo chlorophyll a fluorescence kinetics determined at various times after spraying 1% propanil in the field confirmed progressive weed deterioration. Rice leaves showed a decreased fluorescence for a few hours but exhibited partial recovery from the effects of propanil within 6 h and total recovery within 48 h after spraying. When the leaves were infiltrated with propanil solutions there was good recovery of fluorescence in both weed and crop leaves at 0.01% while at 1% both were drastically affected. With 0.1% propanil, fluorescence in the weed leaves deteriorated progressively while the crop leaves recovered after 4 h of incubation. This suggests that the crop has also an effective endogenous detoxifying mechanism.
Relative persistence of MCPA, MCPB and mecoprop in Saskatchewan soils, and the identification of MCPA in MCPB‐treated soils
Authors: SMITH ALLAN E. , HAYDEN BRIAN J. 
Published: July 2006

Summary:The persistence of MCPA, MCPB and mecoprop was compared at the 2 μg g−1 level, under laboratory conditions, in three Saskatchewan soils at 85% of their field capacity moistures and 20 ± 1°C. Following extraction of the soils with aqueous acidic acetonitrile, the methylated extracts were analysed gas chromatographically for herbicides remaining.Breakdown of all three phenoxyalkanoic acids was rapid; the average half‐lives for MCPA, MCPB and mecoprop being < 7, 6 and 8 days, respectively. Degradation in air‐dried soils was minimal. The presence of MCPA as a degradation product of MCPB was confirmed in all moist soils.
Rapid detection of‘triazine resistant’weeds using chlorophyll fluorescence
Authors: ALI A. , MACHADO V. SOUZA 
Published: July 2006

Summary:A simple and rapid method for the detection of triazine resistant plants is reported, based on chlorophyll fluorescence. Leaf discs were floated in phosphate buffer solution with and without 10−4 M alrazine for 2–4 h. Subsequently, the relative leaf chlorophyll fluorescence (LCF) was measured with a plant productivity fluorometer. Following herbicide uptake LCF in triazine susceptible plants was 2–3 times greater than in the untreated controls; no such LCF changes were observed in triazine resistant plants. Concentration and time course studies were conducted on several species having triazine susceptible and resistant biotypes. The use of this method for field extension purposes is described.
Activité des peroxydase, catalase et glycolate oxydase après traitement avec divers herbicides
Authors: DECLEIRE M. M. , HONOREZ Y. P. , van ROEY G.V. 
Published: July 2006

RésuméDivers herbicides ont été administrés à des plantules de concombres de 17 jours, croissant sur solution nutritive. Les activités des peroxydase, catalase et glycolate oxydase ont été mesurées après 1, 2 et 3 jours dans les feuilles des plantules traitées avec des doses létales d'atrazine, de chlortoluron, de MCPA, d'alachlore et de dichlobenil. Les mêmes déterminations ont été effectuées après 5 h sur plantules préalablement pulvérisées au paraquat et au DNOC. L'atrazine et le chlortoluron ont inhibé l'activité de la peroxydase et stimulé légèrement celle de la catalase. Ces deux enzymes ont été activées par le MCPA, l'alachlore et le dichlobenil et après 3 jours, les rapports peroxydase/catalase ont été respectivement de 0.7; 7 et 14. Le DNOC et le paraquat ont inhibé la catalase. L'activité de la glycolate oxydase a augmenté dans les plantules traitées à l'atrazine, au chlortoluron, au MCPA et au DNOC et a diminué dans celles traitées au dichlobenil et au paraquat.