bluuebunny/crossref_metadata_2025_split huggingface dataset:
In‐vitro metabolism of O,O‐diethyl S‐(N‐methylcarbamoylmethyl) phosphorodithioate by mouse liver
Authors: El‐Oshar Mohamed A. , Dauterman Walter C. 
Published: November 2006

AbstractThe in‐vitro metabolism of O,O‐diethyl S‐(N‐methylcarbamoymethyl) phosphorodithioate in mouse liver was studied. The major route of metabolism was via the mixed‐function oxidases present in the microsomal fraction, which formed the oxygen analogue, O,O‐diethyl hydrogen phosphorothioate and diethyl hydrogen phosphate upon addition of nicotinamide‐adenine dinucleotide phosphate (NADPH). In the absence of NADPH, the carboxylic acid analogue (S‐carboxymethyl O,O‐diethyl phosphorodithioate) was isolated only from the microsomal fraction. Addition of glutathione to the 100 000 g supernatant resulted in no metabolism of the parent compound. However, addition of glutathione to the 10 000 g supernatant resulted in the carboxylic acid formed by amidase activity being further metabolised to O,O‐diethyl hydrogen phosphorodithioate by a glutathione‐dependent reaction.
The activity of some pyrethroids against Periplaneta americana and Blattella germanica
Authors: Chadwick Peter R. 
Published: November 2006

AbstractThe knockdown and contact killing actions of various pyrethroids were compared using Blattella germanica and Periplaneta americana. A wide range of knockdown activity was found; 5‐benzyl‐3‐furylmethyl (1R)‐cis‐3‐(dihydro‐2‐oxo‐3‐thienylidenemethyl)‐2,2‐dimethylcyclopropanecarboxylate (RU 15525) acted fastest, more rapidly than pyrethrins, against B. germanica as well as having a low LD50 value. Topical application and direct spray tests showed that (S)‐α‐cyano‐3‐phenoxybenzyl (1R)‐cir‐3‐(2,2‐dibromovinyl)‐2,2‐dimethylcyclopropanecarboxylate (NRDC 161) was more active as a killing agent, by an order of magnitude, than cismethrin, the next most active compound, and also had considerable knockdown activity. Piperonyl butoxide generally had little synergist effect. Female P. americana were over three times more tolerant than males to a range of insecticides applied topically. Residual knockdown action in the WHO resistance test was observed to provide baseline data. There was little overlap in speed of action between pyrethroids and other insecticides among the compounds tested.
Action of pesticides on earthworms. Part I: The toxicity of cholinesterase‐inhibiting insecticides to earthworms as evaluated by laboratory tests
Authors: Stenersen Jørgen 
Published: November 2006

AbstractThe action of seven cholinesterase‐inhibiting pesticides [aldicarb, carbaryl, carbofuran, oxamyl, paraoxon (diethyl 4‐nitrophenyl phosphate) parathion and trichloronate], the organochlorine insecticide, gamma‐HCH, and the nematicide potassium N‐hydroxymethyl‐N‐methyl(dithiocarbamate) (PHMD) on four earthworm species was investigated by laboratory toxicity tests. Eisenia foetida was the most tolerant species to the pesticides tested. Aldicarb was the most toxic pesticide to this species, causing severe dehydration prior to death or at sublethal concentrations. Aldicarb was also toxic to the other species (Allolobophora caliginosa, A. chlorotica and Lumbricus rubellus), while oxamyl, the other oxime carbamate, was not toxic to any of them. Carbaryl and carbofuran at low concentrations were lethal to A. caliginosa, A. chlorotica and L. rubellus, but E. foetida could tolerate high concentrations without dying, although low concentrations severely affected its ability to work the soil or to disappear from the soil surface. Paraoxon, parathion, trichloronate and gamma‐HCH were moderately toxic with low lethal effect to all species. The ability to work the soil was moderately affected by parathion, trichloronate and gamma‐HCH. PHMD was toxic to all the species. The lethal and non‐lethal effects of the pesticides are discussed in relation to their possible biochemical mode of action in earthworms, and the data are compared with published information from field trials.
Electrical theory and measurements on an experimental charged crop‐spraying system
Authors: Jones Christopher D. , Hopkinson Peter R. 
Published: November 2006

AbstractA series of electric‐field measurements taken in the vicinity of spinning disc atomisers maintained at a high potential is described. Information on the space charge density, droplet mobility and droplet trajectories is deduced from a theory which is developed in the paper. Direct evidence of improved performance in strong winds compared with uncharged sprays was obtained.
Determination of the products of surface‐induced hydrolysis of organophosphorus pesticides
Authors: Mingelgrin Uri , Kljger Lilian , Saltzman Sarina 
Published: November 2006

AbstractA procedure which enables the identification of the hydrolysis products of a number of phosphoric and phosphorothioic esters was developed. This procedure, which includes thin‐layer chromatography (t.l.c.), gas chromatography and u.v. spectroscopy, has been used to demonstrate that surface hydrolysis on kaolinite is a general property of bioactive phosphoric and phosphorothioic esters. The path of hydrolysis was shown to be the breakage of the PO A or PSA bond, where A is the electron attracting moiety of the organic molecule.
Effects of sodium azide and methyl bromide on soil bacterial populations, enzymic activities and other biological variables
Authors: Kelley Walter D. , Rodriguez‐Kabana Rodriguez 
Published: November 2006

AbstractThe application of a granular formulation of sodium azide (Smite 8G), to pine nursery beds at rates of 0, 22.4, 67.2 and 134.5 kg active ingredient ha−1 under water seal or plastic seal, was compared over a 1‐year period with methyl bromide, applied at a rate of 650 kg ha−1, to determine the effects of soil bacterial populations, soil enzymic activities, development of mycorrhizal roots, weed population and incidence of root diseases. Bacterial populations at 24 days after treatment had increased in proportion to the amount of sodium azide added; however, highest numbers of bacteria were recorded from the methyl bromide‐treated plot. At the last sampling date no significant differences were observed in bacterial populations among treatments. Neither sodium azide nor methyl bromide caused permanent changes in soil enzymic activities or adversely affected mycorrhizal root development on pine seedlings. Sodium azide at 134.5 kg ha−1 and methyl bromide both significantly decreased the number of Cyperus spp. plants in plots; however, the number of pine seedlings exhibiting a root disease was highest in plots receiving these treatments.
Time related factors in Heliothis control on cotton
Authors: Morton Neil 
Published: November 2006

AbstractMost factors in Heliothis control on cotton are crucially related to time but all are interrelated one with another and form two complex interactions hinging on the pest life cycle. One is the crop‐pest interaction and the other the control strategy. This paper reviews most of the factors and reports work carried out in Swaziland to elucidate some of them. In the crop‐pest interaction the timing of the initial attack and a cue for spraying can be indicated by development of an alternate host and, in Swaziland, by reference to the average date of maize tassellation. Later infestations are measured by scouting and a comparison is made of the two main systems, the first based on a small part of many plants and used in the USA, and the second based on the whole of a few plants in Africa. Their respective purposes are discussed and economic spray thresholds based on them are presented. The compensatory ability of the plant diminishes as the season progresses but in Swaziland manual bud/flower removal experiments over 3 years on raingrown and irrigated cotton showed that prior to 12 January (9‐12 weeks from planting) removal increased the yield in half the cases whilst later removal could cause a decrease. The natural Heliothis infestation was allowed to remove fruits in an experiment by leaving spray gaps and the results confirmed those of the previous manual experiments except that damage continued for about 2 weeks after spraying restarted. This advanced the critical date to 31 December but up to three sprays could be saved without loss of yield and possibly with a yield bonus. In the control strategy the different stages of the life cycle are considered as targets but the most obvious is normally the first instar larvae. Rapid plant growth can dictate frequent spray applications regardless of deposit persistence which may need to be longer when using aircraft in spite of Heliothis oviposition occurring predominantly on exposed surfaces. Temperature‐independent or fumigant insecticides or those affecting the adult may best be sprayed in the evening when cooler and calmer post‐treatment conditions occur and adults are starting to fly.
Localisation and quantification of elements in biological tissues by electron‐microprobe analysis
Authors: Dick David A. T. 
Published: November 2006

AbstractAn introduction is provided to the basic ideas and theory of electron‐microprobe analysis as applied to biological tissue. The nature of characteristic and continuous X‐rays is outlined. X‐ray detectors, specimen preparation and the relative advantages and disadvantages of thick and thin section techniques are discussed.
Studies of cellular dynamics by laser Doppler microscopy
Authors: Earnshaw John C. , Steer Martin W. 
Published: November 2006

AbstractThe sources and magnitudes of typical molecular, macromolecular and cytoplasmic motions in cells are reviewed and compared with the ability of the conventional light microscope to detect and quantify them. The principles of laser Doppler spectroscopy are introduced; the type and range of motions detectable are reviewed and found to be superior to conventional light microscopy in certain respects. A laser Doppler microscope system has been developed that allows accurate placement of the beam within the cell and combines visual monitoring of the cellular behaviour with the superior resolution of motions from spectroscopy. The system operates with a non‐destructive, low intensity, laser beam that permits continuous monitoring of diffusive and translational motions in living cells.
Mechanism of DDT resistance in larvae of the mosquito Aedes aegypti L.; The effect of DDT selection
Authors: McDonald Alan E. , Wood Roger J. 
Published: November 2006

AbstractSelection with pp'‐DDT was applied to fourth‐stage larvae of Aedes aegypti along four lines, starting with larvae of the F2 generation from crosses between a susceptible strain and each of four resistant strains (two of Trinidad origin and two of Bangkok origin). Larval resistance increased substantially along each line but there was little or no change in the percentage breakdown of DDT to 1,1‐dichloro‐2,2‐bis(4‐chloro‐phenyl)ethylene (pp'‐DDE) in vivo and in no line were these two variables significantly correlated. Percentage breakdown was generally higher at 10 mg than at 50 mg litre−1. DDT uptake (defined as content of DDT+pp'‐DDE) was generally higher after exposure to 50 mg than to 10 mg litre−1. It increased significantly with selection in the TE×NS line; it remained unchanged in the T8 × NS line; and in the other two lines (BSJ × NS and B51 × NS), it increased initially but dropped as selection progressed, the reduction being highly significant in the second of these lines. The amount of internal residual (unmetabolised) DDT tolerated by larvae of the TE × NS line also increased significantly with resistance. The levels in the other lines followed the pattern of uptake, remaining steady in T8 × NS despite the increase in survival, rising at first and then declining in the two Bangkok lines. Thus selection produced a higher tolerance to internal unmetabolised DDT in the two Trinidad lines but led ultimately to a lower content of DDT+pp'‐DDE in the two Bangkok lines. The reasons for this behaviour are discussed.
Mitotic instability in Aspergillus nidulans caused by the fungicides iprodione, procymidone and vinclozolin
Authors: Georgopoulos Spyros G. , Sarris Michael , Ziogas Basil N. 
Published: November 2006

AbstractThe fungicides iprodione, procymidone and vinclozolin were found to increase greatly the frequency of mitotic recombination in diploid colonies of Aspergillus niduluns. Although generally more potent, these fungicides do not appear to differ in their activity from members of a previously suggested ‚aromatic hydrocarbon group’︁ with which they should be classified in this context.
Effects of repeated applications at high rates of chlorthiamid and dichlobenil to blackcurrants
Authors: Clay David V. , McKone Colin E. 
Published: November 2006

AbstractChlorthiamid and dichlobenil were applied to blackcurrants each year for five years at doses up to 54 kg ha−1. Growth and yield were not affected but leaf margin chlorosis was caused at the higher rates. No nitrile residues of dichlobenil or chlorthiamid were found in the fruit but 2,6‐dichlorobenzamide (DCB) was present in most samples tested. There were no adverse effects of the treatments on the taste and flavour of the canned fruit. Nitrile residues in the soil were largely confined to the top 15 cm layer. Amounts detected one year after the previous application did not increase with repeated treatments and were always less than 10% of the annual doses. Nitrile residues were less from dichlobenil than chlorthiamid. The rate of disappearance of soil residues present at the end of the 5‐year treatment period was much slower than that of the freshly applied herbicide. During the period of treatment there was generally less DCB than nitrile in the 0‐15 cm layer but more was found in deeper layers and small amounts were detected at all depths sampled (up to 105 cm). These residues had largely disappeared 3.5 years after the final treatment. Test crops sown on the plots two years after the final treatment varied in susceptibility to the residues as follows; barley and cabbage (unaffected) <wheat<lettuce<carrot (most susceptible). In the following year only the treatments with chlorthiamid at 27 and 54 kg ha−1 caused a decrease in the growth of carrots but all the treatments caused skin abnormality.
Characterisation of bound residues of [3H]triforine in the straw of barley grown in the field
Authors: Rouchaud Jean , Moons Chantal , Meyer Joseph A. 
Published: November 2006

AbstractBarley was grown in an experimental field and, at the growth stage J (during the stem extension stage when the second node of the stem was formed and the next‐to‐last leaf just visible), the aerial part of the plants was sprayed with an aqueous emulsion of a mixture of triforine and [3H]triforine (uniformly labelled in the piperazine ring) at the recommended rate of 250 g triforine ha−1. Barley was harvested when ripe, and the straw was analysed separately. Extraction of the straw with methanol left methanol‐insoluble solids containing an amount of radioactivity (the bound residue) which represented 88 % of the tritium (as with all the subsequently quoted percentages, relative to the total tritium incorporated into the straw). Methanol acidified with hydrochloric acid extracted a further 8% of the triforine‐derived bound residues as radioactive iminodiacetic acid (0.4%). glycine (3.2%), serine (2.0%), ethanolamine (0.2%) and unidentified compounds (2.2%); a neutral detergent solution extracted a further 3% of the radioactive triforine‐derived bound residues as unidentified compounds; these radioactive compounds, which were dissolved by the acidified methanol and by the neutral detergent solution, were thus complexed in the straw to straw constituents. An acid detergent solution extracted a further 58% of the total tritium, which was incorporated by means of σ chemical bonds into the hemicelluloses fraction. Acid hydrolysis of the hemicelluloses yielded a mixture of mono‐saccharides; these were converted into a mixture of osazones (50%), recrystallised several times, and had a constant specific radioactivity, indicating that the mono‐saccharides were tritiated. The plant solids (which contained 19% of the total tritium), left by the acid‐detergent extraction, were processed and separated into the tritium‐containing cellulose (13%) and lignin (6%) fractions. No piperazine was observed in the bound residue of straw. Biochemical pathways are suggested for the radioactive metabolites of [3H]triforine.
Determination of residues of 1‐(2‐cyano‐2‐ methoxyiminoacetyl)‐3‐ethylurea (DPX‐3217) by gas‐liquid chromatography
Authors: Holt Richard F. 
Published: November 2006

AbstractResidues of the fungicide 1‐(2‐cyano‐2‐methoxyiminoacetyl)‐3‐ethylurea (DPX‐3217) in grapes, potatoes, tomatoes and wine were determined by initial extraction with ethyl acetate, clean‐up by liquid‐liquid partitioning and adsorption chromatography, and final determination by gas‐liquid chromatography with a nitrogen‐selective detector. The sensitivity of the method was 0.04 mg kg−1 based on 50‐g samples. Recoveries of the compound added to untreated substrates averaged approximately 92% in the range of 0.04‐5.0 mg kg−1.
In‐vitro metabolism of a mixture of atrazine and simazine by the soluble fraction (105000g) from goose, pig and sheep liver‐homogenates
Authors: Khan Shahamat U. , Foster Thomas S. , Akhtar M. Humayoun 
Published: November 2006

AbstractThe soluble fraction (105 000g) from goose, pig and sheep liver‐homogenates was found to contain an enzyme which metabolised a mixture of atrazine and simazine in in‐vitro incubations by a combination of hydrolysis and partial N‐dealkylation. Complete dealkylation was not observed as shown by the removal of only one alkyl group, but not both, from the compounds containing chlorine or hydroxyl‐groups attached to the triazine ring.
The antifungal activity of alkyl benzimidazol‐2‐ylcarbamates and related compounds
Authors: Eckert Joseph W. , Rahm Michael L. 
Published: November 2006

AbstractThe fungistatic activity against Penicillium digitatum and Diplodia natalensis decreased slightly in ascending a homologous series of alkyl esters of benzimidazol‐2‐ylcarbamic acid from the methyl ester (carbendazim) to the pentyl ester; the hexyl and octyl esters were inactive. 2‐(Acylamino)benzimidazoles were slightly less active than the analogous alkyl benzimidazol‐2‐ylcarbamates. Introduction of a methylene bridge between the benzimidazole ring and the 2‐methoxycarbonylamino group abolished antifungal activity. Methylation of either the carbamate nitrogen or an imidazole nitrogen of carbendazim produced inactive compounds. Replacement of the benzimidazole ring of carbendazim with various other ring systems was accompanied by marked reduction in antifungal activity.
Inhibition of oviposition in the cattle tick Boophilus microplus by certain acaricides
Authors: Mansingh Ajai , Rawlins Samuel C. 
Published: November 2006

AbstractDoses of ten acaricides, ranging from 2.5 to 10 μg, induced about 10‐60% mortality and inhibited oviposition in engorged Boophilus microplus as well as preventing larval hatching from the eggs. The effects of the acaricides were dose dependent. The efficacy of acaricides in reducing the reproductive potential (inhibition of oviposition × inhibition of hatching/100) was in the following order: dimethoate > dioxathion > naled > diazinon > chlordimeform > carbaryl > trichlorphon > phosphamidon > gamma‐HCH > fenitrothion. Most of the acaricides also retarded the oviposition cycle, delaying the peak activity by 4‐8 days. The ovarian development in control ticks reached its peak between the 5th and 7th days before decreasing gradually and ceasing completely between the 16‐20th days after engorgement. The protein content of the ovaries and the rate of incorporation of [14C]glycine into the tissues followed a similar pattern. Carbaryl, fenitrothion and naled inhibited these activities. Chlordimeform stimulated [14C]glycine incorporation and increased the ovarian protein content up to the 13th day before resorption of the oocytes. The eggs from treated ticks were mostly non‐viable and contained more protein; those from dioxathion, carbaryl and chlordimeform treatments had a higher dry weight than the control.
Susceptibility of a dieldrin‐resistant and a susceptible strain of the tick Rhipicephalus evertsi evertsi Neumann, 1897 from East Africa, to carbamate and organophosphorus acaricides
Authors: Lourens Jan H. M. 
Published: November 2006

AbstractA dieldrin‐resistant and a susceptible strain of the tick Rhipicephalus evertsi evertsi Neumann, 1897 from East Africa were compared for susceptibility to nine organophosphorus and a carbamate acaricides, using an internationally approved oil‐based packet test. As only minor differences in response existed between the strains, the presence of cross resistance may be excluded. For some of the acaricides, distinct susceptibility classes were recognised which were probably genetically determined. The tolerances existed independently of the organochlorine‐susceptibility status and were low (by a factor less than 3), except in the case of dimethoate for which resistance factors of up to 10 were present. As susceptibility data were not assessed prior to introduction of the compounds in the field, the lowest susceptibility classes may now be considered as providing baseline data. When compared with data from susceptible reference strains of other ticks such as Boophilus microplus from Australia and R. appendiculatus from East Africa, it is feasible that the tolerances observed in the laboratory will not interfere with practical control.
Comparative modification of insecticide‐resistance spectrum of Culex pipiens fatigans wied. By selection with temephos and temephos/synergist combinations
Authors: Ranasinghe Leonard E. , Georghiou George P. 
Published: November 2006

AbstractThe evolution of strong organophosphorus multiresistance, suppressible by S,S,S‐tributyl phosphorotrithioate (TBPT), in a California strain of Culex pipiens fatigans was examined by further selection with temephos, alone and in combination with the synergists TBPT or piperonyl butoxide (PB). Selection by temephos and temephos + PB increased resistance to higher levels. However, selection by temephos + TBPT virtually abolished TBPT‐suppressible resistance while preventing the emergence of significant alternative resistance mechanisms. The phenomenon of synergism may enable the extended use of an insecticide where alternative resistance mechanisms are either absent or of low efficiency in the target population.