bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stabilisation of the carbamate acaricide promacyl in cattle dipping fluid
Authors: McDougall Kerryn W. , Machin Michael V. 
Published: November 2006

AbstractThe concentration of promacyl declined in cattle dipping fluid, and laboratory experiments were undertaken to establish the cause of breakdown and devise ways of overcoming it. Promacyl declined more quickly in dipping fluid at 15–26°C than at 35°C, with concentrations of the metabolite promecarb increasing as the temperature decreased. Promacyl did not break down in distilled water, other than by hydrolysis at 50°C. The degradation rate of promacyl in dipping fluid increased with the addition of ammonium nitrate and by saturation with air, but it remained unchanged with the addition of copper sulphate, magnesium chloride, urea and chlorhexidine diacetate. When samples which were already breaking down were recharged with promacyl the rate of depletion remained unaltered. Samples inoculated with dip solution already showing promacyl breakdown had increased rates of promacyl degradation (P<0.05). Calcium hypochlorite prevented promacyl breakdown, but only for a short time. Breakdown could be prevented by the addition of the bactericides 2,4‐benzisothiazolin‐2‐one or dichlorophen, or by reducing the pH to <5.0. Data indicated that breakdown of promacyl was due to microbial action.
Degradation rates in soil of 1‐benzyltriazoies and two triazole fungicides
Authors: Patil Shantagouda G. , Nicholls Peter H. , Chamberlain Keith , Briggs Geoffrey G. , Bromilow Richard H. 
Published: November 2006

AbstractThe degradation rates in soil of 1‐benzyltriazole together with six analogues having substituents in the phenyl ring and two commercial triazole fungicides, PP450 and triadimefon, were determined at 15°C and 20 % soil water content. The order of degradation rates of the benzyltriazoles was H > 4‐OCH3 > 4‐F>4‐Cl.4‐≥tert‐C4Hg3,4‐diCl>3‐CF3. Thus, in general, persistence was enhanced by electron‐withdrawing substituents and by lipophilic groups that increased sorption by soil.Of the commercial fungicides, PP450 was degraded very slowly (half‐life 578 days) while triadimefon was quickly converted (half‐life 15 days) to the corresponding alcohol, triadimenol, which in turn was degraded very slowly.The effects of temperature and soil water content on rate of degradation were studied for 1‐benzyltriazole and 1‐(4‐fluorobenzyl)triazole. The rate of degradation of 1‐benzyltriazole was more sensitive to soil temperature and water content than was that of 1 ‐(4‐fluorobenzyl)triazole. The influence of these results on the input data required by models which simulate persistence in field soil is discussed.
Studies on pesticides based on coumarin. III. Synthesis and antifungal activity of substituted 4‐methyl‐coumarins and related compounds
Authors: Singh Rajvir , Abrol Mrs V. , Gupta Bharat B. , Malik Om P. 
Published: November 2006

AbstractA series of substituted 4‐methylcoumarins was synthesised and the members tested for their toxicity towards mycelial growth of seven phytopathogenic fungi in culture. Rhizoctonia solani, Alternaria alternata and Fusarium solani exhibited maximum sensitivity to these compounds whereas Pythium aphanidermatum, Colletotrichum falcatum, Drechslera oryzae and Macrophomina phaseolina were relatively less sensitive. 6‐Ethyl‐3‐n‐ propyl‐7‐hydroxy4‐methylcoumarin (I) was relatively toxic towards all fungi except C. falcatum, P. aphanidermatum and M. phaseolina. The 6‐n‐butyl (III) and 6‐(1, 1, 3, 3‐tetramethylbutyl) (VI) derivatives were highly toxic to R. solani with EC50, values of lμg ml−1.
The pyrethrins and related compounds. Part XXXII. Replacement of the central ester link
Authors: Elliott Michael , Farnham Andrew W. , Janes Norman F. , Khambay Bhupinder P. S. 
Published: November 2006

AbstractThis paper, and the two following, report a detailed examination of the effect of replacement of the central link in pyrethroids by isosteric or isoelectronic groups, and how the resulting change in insecticidal activity depends on the particular groups present in the other parts of the molecule. In this first paper, a wide range (42 variations) of central groups in different combinations are synthesised and tested. Results indicate that with conventionally pyrethroidal acid and alcohol fragments in the molecule, some isosteric replacements are tolerated, but most other variations are unsuccessful, Particularly interesting central groups are COCH2 and CHCHCH2(E).
Degradation and movement of aldicarb residues in Florida citrus soils
Authors: Jones Russell L. , Hornsby Arthur G. , Suresh P. , Rao C. 
Published: November 2006

AbstractThe movement and degradation of the pesticide aldicarb was monitored in two Florida citrus groves. One of these was a bedded grove near Oviedo and the other was located in the central ridge near Lake Hamilton. Soil core samples were collected at 0.3 or 0.6 m depth increments six times over an eight‐month period and were analyzed for aldicarb and its two oxidation products aldicarb suljoxide and aldicarb suljone. These analyses showed a relatively rapid decrease of aldicarb accompanied by an increase in aldicarb sulfoxide and aldicarb suljone; the levels of these carbamate metabolites peaked after about 50 days and then began to decline. The dissipation rate of aldicarb carbamate residues in surface soils corresponded to a half‐life of approximately 20 days at both jield sites. The degradation rate in subsoils appeared to be significantly longer (half‐life greater than 60 days), especially at the Lake Hamilton site.Aldicarb carbamate residue concentrations measured in replicate soil analyses were highly variable, with coeflcients of variation ranging up to 300% for samples collected at the same time and depth. These data point out the need for carefirl design of soil‐sampling strategies (including numbers, timing, and location of samples) in order to obtain statistically valid results from unsaturated zone pesticide monitoring studies.
Promotion of stomatal infiltration of glyphosate by an organosilicone surfactant reduces the critical rainfall period
Authors: Field Roger J. , Bishop Nicholas G. 
Published: November 2006

AbstractThe addition of the organosilicone surfactant ‘Silwet L77’ at 1‐5 ml litre−1 to formulated glyphosate gave complete surface wetting on application to the adaxial leaf surface of perennial ryegrass (Lolium perenne L.). The wetting characteristics of the solution were associated with rapid foliar uptake and near maximal uptake in 3 h compared to greater than 5 h in the absence of ‘Silwet L77’. Evidence is presented showing that solutions containing ‘Silwet L77’ rapidly infiltrate stomata. Rapid uptake did not occur after application to the astomatous abaxial surface of perennial ryegrass leaves.The rapid rate of glyphosate uptake reduced the critical rainfall period to 2 h or less, compared to up to 10 h in the absence of ‘Silwet L77’. The use of ‘Silwet L77’ has major practical implications for the use of glyphosate in regions with unpredictable rainfall or high rainfall frequency.
The synthesis and biological activity of substituted chlorinated benzenedicarbonitriles
Authors: Clifford David P. , Edamura Fred 
Published: November 2006

AbstractA number of chlorinated 1,2‐, 1,3‐ and 1,4‐benzodicarbonitriles monosubstituted by either hydroxy, arylamino, alkylthio, sulphinyl or sulphonyl groups were synthesised and assayed against P. viticola, P. oryzae, V. inaequalis, P. parasitica and a number of other fungi and bacteria. The 1,3‐benzodicarbonitriles were the most active compounds and the alkylsulphiyl and sulphonyl groups the most effective substituents.
Estimating buffer zone widths for pesticide applications
Authors: Payne Nicholas J. , Helson Blair V. , Sundaram Kanth M. S. , Fleming Richard A. 
Published: November 2006

AbstractA technique for estimating the width of buffer zones required around sensitive areas during pesticide applications has been devised and tested. The technique has been used to estimate the buffer width required around water bodies during ground‐based permethrin applications in Canadian forests to prevent significant impact on fish and their food populations. A worst‐ case scenario was developed for environmental impact in water bodies result ing from ground‐based permethrin applications, and a spray application was made under these worst‐case conditions. Permethrin deposit on ground sheets was measured downwind of overlaid crosswind swaths. From these measurements the deposit at various downwind distances from a single crosswind swath was calculated, and a curvilinear regression line fitted to these values. Permethrin deposit downwind of multiple‐swath applications was computed by adding the contributions from individual swaths. Mortality resulting from various permethrin concentrations was measured for Aedes aegypti larvae. Although these larvae are not an important food species for the fish species of interest, salmon and trout, they are more sensitive to permethrin than most aquatic invertebrates. Predicted mortality in populations of this species and Salmo gairdneri, rainbow trout, at various downwind distances from the permethrin application was calculated from the toxicological and spray‐cloud dispersal data. Buffer width was estimated by choosing an acceptably low mortality, and determining the downwind distance at which this value was obtained. For example, a 20 m swath width was found to be adequate to limit mortality in A. aegypti andS. gairdneri populations to 10 and 0.1% during ground‐based permethrin applications.
Molecular properties of the apamin binding protein associated with a calcium activated potassium channel
Authors: Seagar Michael J. , Marqueze Beatrice , Couraud François 
Published: November 2006

AbstractApamin, a 2‐kdalton peptide from bee venom, is a potent convulsant. Its neurotoxic action has been attributed to specific blockade, at nanomolar concentrations, of the slow Co2+ activated K+ current (IAHP) that underlies the late afterhyperpolarisation in certain neurons. Mono[125I] iodoapamin binds with high affinity to intact cultured neurons (Kd = 30 PM, Bmax = 500‐1000 sites/cell) and synoptic membranes (Kd = 30 PM, Bmax = 30 fmol mg protein−1). Apamin contains two primary amines (alpha cysl and epsilon lys4) that can be modified to produce photoactivatable arylazide derivatives. Photoaffinity labeling with these derivatives has identified receptor polypeptides of 86 and 59 kdaltons accessible from the alpha cysl position and 33 kdaltons accessible from the epsilon lys4 position of the bound ligand. This suggests that apamin binds at the interface between 3 putative K+ channel subunits. Radiation inactivation studies indicated a target size of 84‐115 kdaltons. The simplest interpret at ion is that the 86 kdalton chain alone carries the neurotoxin binding site.The apamin binding protein can be extracted from rat brain membranes using sodium cholate. Scatchard analysis of equilibrium binding data revealed a single class of non‐interacting sites with Kd = 40 pm and Bmax = 17 fmol mg protein−1. As in membrane‐inserted receptors, apamin binding is stimulated by occupation of a K+ ion site that saturates at low millimolar concentrations. Other cations can be substituted for K+ with an affinity sequence: K+ = Tl+ = Rb+ > Cs+ > NH+4 > Li+ or Na+. The K+ channel Mockers quinidine and tetraethylammonium + displaced apamin from its solubilised receptor at concentrations similar to those required to block flux through apamin‐sensitive channels. Analysis by sucrose gradient centrifugation showed that the receptor sediments with S20=20, corresponding to a molecular weight of about 700 kdaltons. However, as much as 50%of this could be contributed by the detergent.Receptor sites for [125I]‐apamin have also been detected and identified by photoaffinity labeling in primary cultured astrocytes and heart cells as well as in membrane preparations from liver and smooth muscle. A 86–87 kdalton componet was was present in all these tissues whereas the 57–59 and 33kdalton polypeptides were revealed in some but not in others, These observations support the hypothesis that the larger chain contains the apamin binding site while the two smaller polypeptides are noncovalently associated perpheral subunits.
Synthesis, insecticidal activity and pyrethroidal mode of action of new tin ether derivatives
Authors: Tsushima Kazunori , Yano Toshihiko , Umeda Kimitoshi , Matsuo Noritada , Hirano Masachika , Ohno Nobuo 
Published: November 2006

AbstractA novel range of trimethylstanniomethyl ethers of well known pyrethroid alcohols were synthesised, and their insecticidal activities and modes of action as insecticides were investigated. Among them, ethers from three types of alcohol (3‐phenoxybenzyl, 4‐fluoro‐3‐phenoxybenzyl and 6‐phenoxy‐2‐pyridylmethyl) showed remarkable insecticidal activities against rice stem borers, houseflies and German cockroaches.According to electrophysiological studies on the abdominal nerve cords of German cockroaches, trimethylstanniomethyl 6‐phenoxy‐2‐pyridylmethyl ether induced a rapid decline in spontaneous firing similar to that from tetramethrin. However, insecticidal trimethyltin chloride caused an entirely different response.These observations suggest that the present tin ether derivatives resemble pyrethroids, rather than the insecticidal tin compounds known so far.
Assessment of canopy and ground deposits of fenitrothion following aerial and ground application in a northern ontario forest
Authors: Sundaram Kanth M. S. , Millikin Rhonda , Sundaram Alam 
Published: November 2006

AbstractSpray deposit patterns on simulated and live foliage of balsam fir and white birch were determined at different heights and at periphery and interior locations of the tree crown, following aerial and ground applications of fenitrothion formulations over a boreal forest near Searchmont, Ontario. Droplet size spectra and AI deposits were assessed at ground level with ‘Kromekote’ card/glass plate units. Aerial application was made with a Cessna 188 aircraft fitted with ‘Micronair’ AU3000 atomizers. For ground application, a ‘Soloport’ 423 backpack mistblower fitted with an extension tube and a diffuser nozzle at the tip was used.Deposit data on the ground samplers indicated significantly larger droplets and greater deposits from the aerial spray trial than from the mistblower treatment. However, foliar deposits at tree canopy level were only slightly higher in the former trial than in the latter.Analysis of spray deposits on simulated and live fir foliage showed definite gradients in deposit levels, decreasing from top to bottom crown, and from periphery to inner tree crown. In the birch tree crown, such gradients were not observed. The simulated leaves generally acted as better collectors of spray droplets than the natural leaves. The overall mean deposit values, expressed in ng cm−2, showed a wide variation, although there was generally a close relationship between the deposits on the simulated and natural surfaces.
Physiological and structural aspects of adipokinetic hormone function in locusts
Authors: Goldsworthy Graham J. , Wheeler Colin H. 
Published: November 2006

AbstractDuring trivial flight in locusts, carbohydrates are the main energy source for the flight muscles, but during long‐term (migratory) flight, lipids mobilised from the fat body are utilised. The supply of fuels to the flight muscles, and the balance between fuels, is determined by peptidic adipokinetic hormones, AKH‐I and AKH‐II, released from the corpora cardiaca. These peptides also indirectly effect changes in lipid‐transporting mechanisms in the haemolymph, and regulate a lipoprotein lipase necessary for lipid uptake by the flight muscles. The sequences of the AKHs of locusts are known and they are members of a family of invertebrate neuropeptides. Extensive structure/activity studies for the action of AKHs on lipid mobilisation have been carried out and, together with studies on secondary structure, the structural features necessary for biological activity are being elucidated. Such information will be of great importance in receptor studies for these hormones, and in the development of powerful agonists and antagonists.
Disposal of concentrated solutions of diazinon using organic absorption and chemical and microbial degradation
Authors: Mullins Donald E. , Young Roderick W. , Palmer Christopher P. , Hamilton Robert L. , Sherertz Peter C. 
Published: November 2006

AbstractPeat moss has been found to be an effective ‘organic matrix’ for the absorption and degradation of diazinon in experimental disposal pits. High concentrations of diazinon sorbed onto nutrient‐enriched commercial grade peat moss were rapidly degraded. Pits treated with diazinon concentrations ranging from 4000 to 32000 mg kg−1 contained less than 1 to 7 mg kg−1 after 18 weeks. Initially, degradation probably was due to hydrolysis resulting from the effects of heat, moisture, low pH and some microbial activity. Further degradation of the hydrolysis product, IMHP, was most likely due to microbial activity. The results obtained suggest that a managed degradation pit, containing a nutrient‐enriched organic matrix (peat moss), might provide a useful means for absorbing and neutralizing waste pesticide formulations because the materials used in this system are readily available and the system may be regenerative so that it can be used repeatedly.
A biopolymer‐based pesticide delivery system for insect suppression in stored grains
Authors: Singh Satish K. , Fan L. T. 
Published: November 2006

AbstractDegradation of grain quality during storage is mainly caused by insects and microorganisms. To protect against insects, prevailing practices usually require the application of pesticides and fumigants directly to the stored grain; long‐term storage can involve repeated applications. Direct application results in accumulation of chemical residues on the grain, especially from pesticides. A simple delivery system, in which the pesticide (chlorpyrifosmethyl) is incorporated in a biopolymer (xanthan gum), has been formulated with the objective of reducing these residues while increasing the period of effectiveness of a single application. The biopolymer‐based formulation was compared to a conventional formulation on the basis of bioassay tests and residue analysis. The biopolymer‐pesticide formulation was effective over a longer period of time and produced significantly smaller residues than the conventional emulsifiable concentrate formulation.
Toxicity and electrophysiological effects of Spilanthes amella Murr. extracts on Periplaneta americana L.
Authors: Kadir Habsah A. , Zakaria Muhamad B. , Kechil Abdul A. , Azirun Moh D. S. 
Published: November 2006

AbstractThe potential insecticidal activity of Spilanthes acmella Murr. (Compositae) extracts was assessed in this study. The extracts were shown to be toxic against adults of American cockroach, Periplaneta americana L. The active component in S. acmella extract was isolated and identified as N‐isobutyl‐2,6,8‐decatrienamide (spilanthol). The results from topical application of spilanthol show that it has a high acute toxicity and spilanthol was the most potent compound when compared to three conventional insecticides. The potency was found to be 1.3, 2.6 and 3.8 times more toxic than carbaryl, bioresmethrin and lindane, respectively. Electrophysiological studies indicated immediate hyperexcitation followed by complete inhibition of the cockroach cercal nerve activity.
Isolation and characterisation of biologically‐active compounds from some plant extracts
Authors: Peterson Glenn S. , Kandil Mohamed A. , Abdallah Mounir D. , Farag Abdel‐aal A. 
Published: November 2006

AbstractOf the numerous fractions obtained from the crude plant extracts of Chenopodium ambrosioides, Conyza dioscordisis and Convolvulus arvensis, 11 were found to be active against stored grain pests. The chemical structures of compounds present in the 11 fractions were found by gas chromatography/mass spectrometry to include predominantly long‐chain fatty acid esters of hexadecanoic, arachidonic, and octadecanoic acids.
Photodegradation of the organophosphorus insecticide idofenphos
Authors: Walia Suresh , Dureja Prem , Mukerjee Sunil K. 
Published: November 2006

AbstractPhotodecomposition of the organophosphorus insecticide iodofenphos (O‐2,5‐dichloro‐4‐iodophenyl O,O‐dimethyl phosphorothioate) has been studied in solution and on glass, soil and leaf surfaces. Iodofenphos underwent dehalogenation, oxidation and clearage of the P‐O‐aryl linkage on irradiation in hexane and methanol and produced a mamber of photo‐products which were characterised by 1H‐NMR and mass spectroscopy. It has been observed that, as compared to dark conditions, the degradation of iodofenphos on soil, glass and leaf surface was accelerated under illuminated conditions.
Synthesis and pesticidal activity of some quinazolin‐4(3H)‐one derivatives
Authors: Sen Gupta Anil K. , Pandey Ashok Kumar 
Published: November 2006

AbstractA number of quinazolin‐4(3H)‐one carbothioamides, pyrazoles, pyrazolones and tetrazole derivatives have been synthesised by the reaction of 2‐hydrazino‐3‐(4‐substituted phenyl)‐quinazolin‐4(3H)‐ones with the appropriate aryl isothiocyanate, acetyl acetone, ethylacetoacetate and nitrous acid. All the compounds were tested in vitro for antibacterial, insecticidal and antifungal activity and found to have some activity.
Mode of action of fixed oils against eggs of Callosobruchus maculatus (F.)
Authors: Don‐Pedro Kio N. 
Published: November 2006

AbstractStudies on the mode of action of fixed vegetable oils on Callosobruchus maculatus eggs revealed two possible mechanisms of action which may be complementary: (1) that the oils exert lethal action slowly by drastically reducing respiratory activity and elimination of toxic metabolites as a result of the oil ‘barrier effect’, and (2) direct toxic effects of oil or oil constituents that possibly penetrate the eggs.The slow lethal action of oil was demonstrated by the continuous low level respiratory activity (measured by carbon dioxide emission) of dying eggs over a six‐day monitoring period, and the fact that a significantly higher proportion of the dead eggs found on groundnut or traditional coconut oiltreated grains developed up to the late embryonic stage (first instar larvae) when compared with the control. Furthermore, in an experiment carried out by trapping C. maculatus eggs on oil‐treated and untreated artificial membrane (Sellotape), it was found that oiling did not affect egg development up to the late embryonic stage but prevented hatching of significantly higher numbers of developed first instar larvae.Eggs that successfully hatch on oily grain surfaces may find it more difficult to penetrate, since egg attachments on such surfaces were found to be significantly less secure than on the control.The proposed modes of action show that the complete spread of an oil film over the surfaces of a commodity is vital for the successful utilisation of fixed oils as stored‐product protectants.
Structure—activity relationships of organotin biocides and Ceratocystis ulmi
Authors: Eng George , Coddington Stephen P. , Stockton Laura L. , Acholonu Alexander D. W. 
Published: November 2006

AbstractThe effect of organotin compounds on the growth of Ceratocystis ulmi, the causative agent of Dutch elm disease, was studied in shake culture. Triphenyltin, (C6H5)3SnX, tricyclohexyltin, (C6H11)3SnX, and tributyltin, (C4H9)3SnX, compounds were all effective in the inhibition of C. ulmi in vitro. The anionic group, X, did not play a major role in the inhibitory activities of these compounds, suggesting that the species involved in the inhibition is R3Sn+ or the hydrated cation.