bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies on octylphenoxy surfactants. Part 2: Effects on foliar uptake and translocation
Authors: Stevens Peter J. G. , Bukovac Martin J. 
Published: November 2006

AbstractThe effects of octylphenol (OP) and four of its ethoxylated derivatives on uptake into, and distribution within, maize leaf of 2‐deoxy‐glucose (2D‐glucose), atrazine and o, p′‐DDT are reported. The surfactants and OP (2 g litre−1 in aqueous acetone) increased the uptake, at both 1.5 and 24 h, of the three model compounds (applied at 1 g litre−1) having water solubilities in the g, mg and μg litre−1 ranges. The uptake of 2D‐glucose was positively correlated with the hygroscopicity of the surfactants. The uptake of DDT and atrazine increased with the uptake of the surfactants, being inversely related to their hydrophile:lipophile balance (HLB). Uptake of 2D‐glucose and atrazine was enhanced at high humidity, the relative enhancement for atrazine increasing with increasing ethylene oxide (EO) content of the surfactants. A significant proportion of the atrazine and DDT entering the leaf was recovered from the epicuticular wax, the amount of atrazine recovered from the wax increasing with the EO content of the surfactants. The proportion of the surfactants taken up which was recovered from the epicuticular wax was minimal at an EO content of 12.5–16 mole equivalents. The appearance of the deposits on the leaf surface differed markedly among the surfactants, with similar trends for all three chemicals and without visible evidence for infiltration of the stomatal pores. The total quantities of glucose and atrazine translocated were increased by all surfactants but that of DDT was not, despite increases in uptake of up to 7.5‐fold. Relative translocation (export from treated region of leaf as a percentage of chemical penetrating beyond the epicuticular wax) was reduced in all cases in the presence of surfactant. Up to 30% of the applied [14C]chemicals was not recovered from the treated leaf after 24 h. The reduced recovery of 2D‐glucose, but not that of atrazine and DDT, was largely attributable to movement out of the treated leaf, with approximately 70% of the chemical taken up being translocated basipetally. Loss of atrazine and DDT was a result of volatilisation. There was no evidence that either [14C]2 D‐glucose or [14C]atrazine was metabolised to [14C]carbon dioxide.
Influence of temperature on physical properties of non‐aqueous pesticide formulations and spray diluents: Relevance to u.l.v. applications
Authors: Sundaram Alam 
Published: November 2006

AbstractThe viscosity, surface tension and volatility of a range of ultra‐low‐volume (ULV) spray diluents and pesticide formulations were measured at 5°C and 20°C. For u.l.v. application of 1.0 to 1.5 litre ha−1 through conventional boom and nozzle systems or rotary (Micronair) atomisers, it is concluded that the spray medium should have a viscosity of ⩽30 mPa s at 20°C. The surface tension values covered only a narrow range and showed little temperature dependence. There was no clear optimum and all surface tensions within the range measured would appear to be acceptable for ULV applications. The volatility factor, 1/(A.T1/2), where A represents the percentage of non‐volatile material in the spray mixture and T1/2, the half‐life (minutes) of evaporation, should be <40 times; 10−5.
Triadimenol soil residues following tobacco seedbed drenches to control sore shin of transplants
Authors: Cole James S. , Zvenyika Zvenyika , Toet Leendert 
Published: November 2006

AbstractTriadimenol residues were monitored during a four‐year period in sandy soil following annual drenches (2 litre m−2) over tobacco seedbeds and in rotatinos with one or two years of Rhodes grass (Chloris gayana) followed by tobacco. Residues in the 0–10 cm zone were proportional to rates of application and did not accumulate during the four‐year period. Maximum concentration two months after treatment was found in the 5–7–5 cm zone. They inhibited the emergence and growth of Rhodes grass, though not permanently. Recolonization of the soil by Rhizoctonia solani was delayed and there was little effect on emergence and growth of tobacco seedlings.
Influence of physical properties on droplet size spectra and deposit patterns of two mexacarbate formulations, following spray application under laboratory and field conditions
Authors: Sundaram Alam , Sundaram Kanth M. S. , Leung John W. , Holmes Stephen B. , Cadogan Beresford L. 
Published: November 2006

AbstractThe influence of viscosity, density, surface tension, volatility and apparent viscosity‐shear rate relationship on droplet‐size spectra and deposit characteristics of two mexacarbate (4‐dimethylamino‐3,5‐xylyl methylcarbamate) formulations, one oil‐based and one water‐based, was studied following spray application under laboratory and field conditions. The oilbased formulation had a higher viscosity, a higher apparent viscosity at high shear rates and a lower volatility than the water‐based formulation; application through rotary atomisers gave larger droplet sizes, more droplets cm−2 and deposits of the active ingredient ha−1 than those from the water‐based formulation in both the laboratory and field studies. Both formulations had similar surface tensions and densities and, therefore, the contribution of these properties to droplet‐size spectra could not be determined. Among the three properties (viscosity, apparent viscosity‐shear rate relationship and volatility), volatility contributed most to the deposit patterns of the two formulations.
Influence of formulation properties on droplet size spectra and ground deposits of aerially‐applied pesticides
Authors: Sundaram Alam , Retnakaran Arthur 
Published: November 2006

AbstractThe influence of the physical properties of the spray liquid on droplet size spectra and ground deposits of aerially‐applied pesticides was studied using heavy (high‐viscosity) oil‐ and water‐based suspensions of wettable powders (w.p.), a clear solution in a light (low‐viscosity) oil, and an emulsion‐suspension containing a bacterial control agent. The heavy oil provided a highly viscous spray medium, 52 to 64 mPa s (at a shear rate of 480 s−1), resulting in large droplet sizes and a high deposit on the ground sampling units. When the spray medium was thickened with petroleum jelly to keep the w.p. in suspension during overnight storage, the viscosity became excessively high (102 mPa s at 480 s−1), and the droplet spectrum was undesirably coarse and resulted in poor coverage of the spray plot and low deposits. The light‐oil‐based solution (ca 4 mPa s), provided a finer droplet spectrum and lower deposits than the heavy‐oil‐based formulations. The water‐based suspensions of the w.p. (ca 2 mPa s), showed Newtonian behaviour, whereas the emulsion‐suspension (ca 240 mPa s at 480 s−1) showed pseudoplastic behaviour. Consequently, the emulsion‐suspension provided a markedly different droplet spectrum from that of the suspensions of the w.p. Nevertheless, all three aqueous media provided deposits comparable to those of the light‐oil‐based solution, markedly lower than the heavy‐oil‐based suspensions. The study indicated that highly viscous Newtonian formulations should be avoided in pesticide applications using Micronair AU3000 atomisers at the volume rate (4–7 litre ha−1) used here if high atomisation efficiency is required.
Broad versus narrow‐spectrum herbicides and the future of mixtures
Authors: Martin Trevor J. 
Published: November 2006

AbstractThe weed flora of cereals is subject to changes in husbandry methods such as cultivations and crop rotations. The herbicide chemist inevitably has to aim at a moving target. Herbicides themselves apply a selection pressure to the weed flora and when newly introduced often give exceptional results. Continued use allows the less‐susceptible species to become dominant and herbicide mixtures may prove necessary. The concept of mixtures is not new; the phenoxy‐acid herbicides were being formulated together in the 1960s. More recently bromoxynil and ioxynil have been added to assist in the control of more difficult species like mayweeds and parsley piert. Grass weeds, which have been encouraged by minimum‐cultivation techniques, can now be controlled, in addition to broad‐leaved weeds, by suitable mixtures.Completing the weed spectrum is the most obvious reason for mixing two compounds in a formulation or in the spray tank but synergistic interaction, combination of different modes of action, simple convenience and lengthening a product's commercial life may all be involved.Despite the very large choice of products for use in UK cereal crops there is not a single herbicide that could not be replaced by more effective compounds, safer to the crop, more flexible in application criteria, and with generally more reliable action. The chances of new compound discovery are decreasing and the fluctuations in the weed flora make it difficult to aim at specificity. The development of resistant biotypes within species seems to happen rather slowly and compounds with less specificity or in mixture with others having different sites of action would almost certainly help to avoid the problem.
Fenvalerate wash‐off from cotton plants by rainfall
Authors: McDowell Leslie L. , Willis Guye H. , Southwick Lloyd M. , Smith Sammie 
Published: November 2006

AbstractInformation on rainfall wash‐off of foliar‐applied pesticides is needed in developing mathematical models to predict the transport of pesticides to soil and in run‐off from croplands. Fenvalerate [(RS)‐α‐cyano‐3‐phen‐oxybenzyl (RS)‐2‐(4‐chlorophenyl)‐3‐methylbutyrate] is used extensively for cotton (Gossypium hirsutum L.) insect control in the southern United States during July, August and September, which are months of high‐intensity thunderstorms. Fenvalerate was washed from mature cotton plants by the use of a multiple‐intensity rainfall simulator. Fenvalerate concentration in wash‐off from plants was independent of rain intensity. When 25 mm of rain was applied at 7, 13, 26 and 51 mm h‐1 just2 h after fenvalerate was applied at 0.224 kg ha‐1, 38 (±10)% of the fenvalerate load on the plants was washed off. Fenvalerate concentrations in storm wash‐off decreased with wash‐off volume as hyperbolic functions. Rainfall amount affected the wash‐off of fenvalerate from cotton to a greater extent than did rainfall intensity. This information greatly simplifies modelling the movement of fenvalerate from plant canopy to soil during natural storms.
Effect of formulation properties on ground and foliar deposits of two insecticides in flushed and one year‐old balsam fir needles following aerial application
Authors: Sundaram Kanth M. S. , Raske Arthur G. , Retnakaran Arthur , Sundaram Alam , West Rick J. 
Published: November 2006

AbstractA study was conducted in 1985 in Newfoundland to investigate the interrelationships between the physical properties of spray formulations, droplet‐size spectra and deposits on ground sampling units, and deposits on flushed and one‐year‐old balsam fir foliage following aerial application of aminocarb and fenitrothion at different dosage rates, but using the same volume rates. The fenitrothion formulations were pseudoplastic, because of the presence of polymeric ingredients, and provided higher deposits on the ground sampling units and on foliage than the aminocarb formulations, which were nearly Newtonian. At similar dosage rates, the ground deposits of fenitrothion were about twice those of aminocarb, whereas the corresponding foliar deposits were about 6 to 8 times higher than those of aminocarb, suggesting possible advantages of pseudoplastic formulations in providing optimum droplet sizes for enhanced deposition on balsam fir needles.The foliar deposits generally showed an increase when the dosage rates of the two insecticides were increased. Deposits in flushed foliage were slightly higher than those in mature foliage, probably due to the location of the flushed needles at the extreme periphery of the tree canopy.
Effects of the pyrethroid insecticide, WL85871 and phosalone on adults and progeny of the leaf‐cutting bee Megachile rotundata F, pollinator of lucerne
Authors: Tasei Jean‐Noël , Carre Serge , Bosio Pierre Gustave , Debray Philippe , Hariot Jean 
Published: November 2006

AbstractExperiments have been carried out to compare the effects of phosalone and the pyrethroid insecticide, WL85871 on the alfalfa leaf‐cutting bee. Laboratory trials using male adults exposed to treated filter papers showed that WL85871 at the rate of 15 g ha−1 caused mortality equal to or less than that with phosalone at 1000 g ha−1. At the rate of 10 g ha−1, the pyrethroid was less harmful than phosalone. Populations of about 400 females were reared in 4 flowering lucerne fields. One was the control and was not treated, the three other treatments were: A=phosalone at 1000 g ha−1, B=WL85871 at 10 g ha−1, C=WL85871 at 15 g ha−1. Two days after the treatments, counts of live females in artificial nesting sites showed the losses due to A, B, C to be respectively 31%, 21% and 12%. After hibernation and incubation of the progeny larvae, little effect of the treatments could be observed. No residues were detected in live larvae. The maximum residues found in leaves in nests were 71 mg kg−1 of phosalone and 1 mg kg−1 of WL85871. Much lower residues were found in pollen provisions, where the maximum values were 1 mg kg−1 of phosalone and 0–07 mg kg−1 of WL85871.
Toxicity and mode of action of reductively dechlorinated cyclodiene insecticide analogues on houseflies (Musca domestica L.) and other diptera
Authors: Brooks Gerald T. , Mace David W. 
Published: November 2006

AbstractThe toxicities of reductively dechlorinated analogues of dieldrin and some of its photochemical rearrangement products were compared with those of reductively dechlorinated analogues of endrin, endosulfan and isobenzan, against houseflies (Musca domestica L.), blowflies (Calliphora vicina R‐D) and in some cases, fleshflies (Sarcophaga barbata Parker) by topical application of the compounds in acetone. Some of the known toxic oxidative metabolites of dieldrin and endrin were also included for comparison. The chlorine atoms at C‐1 and C‐8 (bridge‐end) of the hexachlorobicyclo[2.2.1]hept‐2‐ene nucleus were retained in all of the analogues tested, while those at C‐9, C‐10 (ethylenic) and C‐11 (dichloromethane bridge), or their equivalent in the photochemical rearrangement products, were variously replaced by hydrogen atoms. The four‐fold increase in toxicity obtained when both of the C‐9 and C‐10 chlorine atoms in dieldrin were replaced by hydrogen appeared to be unique for this compound. Similar increases in potency also resulted from the selective reductive monodechlorination of the endosulfan isomers but in dechlorinated compounds from other series of analogues, toxicities were either unchanged or reduced. Thus, the effect of reductive dechlorination depends on the structure of the remainder of the molecule. Reductive dechlorination of the C‐11 dichloromethane bridge had the most consistent effect on toxicity; the anti‐C‐11 chlorine atom was generally more important for toxicity than the syn‐C‐11 chlorine atom, with large differences between the toxicities of these isomers in some cases. The results, which support a suggested structural analogy between the cyclodienes, lindane, and convulsant, substituted γ‐butyrolactones such as picrotoxinin, are discussed in relation to current theories of cyclodiene insecticide action.
A rapid and sensitive method for gas‐liquid chromatographic determination of N‐nitrosodimethylamine in formulations of chlormequat chloride
Authors: Wigfield Yuk Y. , Lacroix Mario D. 
Published: November 2006

AbstractA rapid and sensitive method for the isolation, clean‐up and gas‐liquid chromatographic determination of trace quantities of N‐nitro‐sodimethylamine (NDMA) in an aqueous formulation of 2‐chloroethyltrimethylammonium chloride (chlormequat chloride) is reported. Seventeen samples of two different formulations were collected and analyzed. The levels of NDMA ranged from 0.08 to 0.2 μg g−1 of chlormequat chloride. The minimum detectable amount was 0.01 ng which is equivalent to 0.01 μg g−1 or 0.03 μg g−1 depending on the concentration of the active ingredient in the formulation. Recoveries from the samples spiked with NDMA standard at 0.23, 0.17 and 0.11 μg g−1 were 90–102% with a mean of 98.4% and an overall coefficient of variation of 3.7%. The detector response was found to be linear within the range 0.05 ng to 0.2 ng.
Enhanced degradation of iprodione and vinclozolin in soil: A simple colorimetric test for identification of rapid‐degrading soils
Authors: Walker Allan 
Published: November 2006

AbstractMeasurements by gas‐liquid and high performance liquid chromatography confirmed that 3,5‐dichloroaniline was an important degradation product of iprodione in soil, and demonstrated that it could be extracted in relatively high concentrations when iprodione degradation was rapid. A colorimetric test based on the production of a diazo colour complex was shown to differentiate between amounts of the aniline in the range from 2 to 15 μg. The test was used to examine 3,5‐dichloroaniline production from iprodione incubated at 50 mg kg−1 in 33 soils with previously‐measured iprodione degrading properties. A positive colour reaction in acetone extracts made after 3 days was obtained with those soils in which the time to 90% degradation of iprodione was less than 6 days. A positive reaction after 7 days was obtained when this time was less than 14 days, and a positive reaction after 10 days was associated with a time to 90% degradation of less than 22 days. Preliminary studies with vinclozolin indicated that the test could also be used to identify soils which rapidly degrade this fungicide.
1,2‐Diphenylaziridines as pesticides: Studies on acute toxicity and delayed effects
Authors: Dahlman Douglas L. , Kadaba Pankaja K. 
Published: November 2006

AbstractThe insecticidal activities of 15 different 1,2‐diphenylaziridines were evaluated. These compounds are readily obtained by photolysis of 1,2,3‐triazolines; the latter can be conveniently prepared by the addition of diazomethane to Schiff bases in dioxane in the presence of water. Compounds containing a chloro, bromo or trifluoromethyl group in the para position of the 1‐phenyl and a chloro in the ortho position of the 2‐phenyl caused acute toxicity in 5th‐instar Manduca sexta larvae via both oral and topical routes of exposure. Lower concentrations resulted in delayed effects such as reduced growth rate, pupal and adult malformations and reduced fecundity. When either phenyl group was unsubstituted, the activity was reduced. Unsubstituted 1,2‐diphenylaziridine was inactive. Topical applications of l‐(4‐fluorophenyl)‐2‐(2‐chlorophenyl) aziridine were active against representative species in the insect orders Lepidoptera, Coleoptera and Orthoptera.
An analytical study of formulations containing malathion
Authors: Mason David J. , Crozier Brian 
Published: November 2006

AbstractA total of sixty‐five samples of eighteen different commercial formulations containing malathion were examined in this study. Twelve formulations were found to have a malathion content which was in general agreement with that declared. However, one of these twelve formulations (an emulsifiable concentrate) contained a high level of isomalathion. Five formulations (all emulsifiable concentrates) had significantly lower malathion contents than those declared and were contaminated with malathion analogues, present at concentrations ranging from c.2 to over 100 % mass/mass of the malathion found. These analogues of malathion appear to have resulted from the transesterification of malathion with alcohols used as formulating agents. One formulation (a dustable powder) was found to contain no malathion above the detection limit. Many of the formulations failed tests of their physical properties.
The pyrethrins and related compounds. Part XXXIII. Effective combinations in the gemdimethyl‐central group region of non‐ester pyrethroids
Authors: Baydar Ahmet E. , Elliott Michael , Farnham Andrew W. , Janes Norman F. , Khambay Bhupinder P. S. 
Published: November 2006

AbstractSynthesis and testing for insecticidal activity ofa wide range of combinations representing simultaneous variation in the acid or alcohol and central fragments of non‐ester pyrethroids reveals strong interactions between these changes, When the gemdimethyl (CMe2), or the equivalent cyclopropyl, group is present in the central chain rather than in a side chain, a new set of requirements for effective central groups applies; those identified as conferring highest activity in this situation are ; (CH2)3; CH2CO. CH2 and CH2O. CH2. Other variations establish the limits to structural changes within these combinations, for activity to be retained.
Minimum concentration levels of methyl bromide required for full efficacy against seven species of stored‐product beetle at two temperatures
Authors: Bell Christopher H. 
Published: November 2006

AbstractThe dosages of methyl bromide required to control insect pests can be expressed as concentration, time (Ct) products for concentrations down to a certain minimal level, here defined as the efficacy threshold, below which Habers Ct rule (C×t=k,a constant for mortality) no longer applies. Twelve strains of seven species of stored‐product beetle were tested to identify efficacy threshold concentrations at 15°C and 25°C. For each strain the efficacy threshold was higher at 25°C than at 15°C. Different species differed widely in the threshold levels identified. Strains with a higher than usual tolerance to methyl bromide than their standard stock counterparts had slightly higher efficacy thresholds at 25°C but not at 15°C. The order of tolerance of the standard stocks to methyl bromide at 15°C was Tribolium confusum> T. castaneum> Oryzaephilus surinamensis> Rhyzopertha dominica> Sitophilus granarius> S. zeamais> S. oryzae, and at 25°C Tribolium castaneum > T. confusum> R. dominica> O. surinamensis> S. granarius> S. zeamais> S. oryzae. The order of efficacy thresholds largely reflected the order of susceptibility, S. oryzae and S. zeamais having the lowest efficacy thresholds of about 0.6 mg litre−1 at 15°C and 1.3‐2.0 mg litre−1 at 25°C, while Tribolium spp. had the highest, 1.3‐2.0 mg litre−1 at 15°C and 2.5‐4.0 mg litre−1 at 25°C.
Residues of HCH in milk after its oral administration or dermal application to indian buffalo, Bubalus bubalis (L.)
Authors: Kapoor Sudesh K. , Kalra Rajinder L. 
Published: November 2006

AbstractThe excretion of HCH (hexachlorocyclohexane) residues in the milk of Indian buffalo, the main milch cattle of India, after oral or dermal exposure to technical HCH was studied. Following the intake of 10, 25,50 and 100 mg of technical HCH by different groups of buffaloes, HCH residues in milk showed an initial rapid rise but soon attained a dose‐dependent equilibrium. The transfer coefficient of HCH residues in milk fat at 'plateau' showed an average value of about 15%. Half‐life values for the rate of decline of HCH residues during the post‐dosing period were computed according to a two open‐compartment model. Dermal application of technical HCH to buffaloes also resulted in significant residues in milk. The proportions of alpha‐, beta‐, gamma‐ and delta‐isomers of HCH in milk of buffaloes following oral and dermal routes of exposures were different. The significance of these results in the regulation of HCH residues in milk is discussed.