bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of MCPA and MCPB on 32P accumulation and its incorporation into ATP in Vicia faba L.
Authors: Matlib M. A. , Kirkwood R. C.
Published: November 2006

Treatment of excised bean root tissue with MCPA and MCPB resulted in a reduced uptake and incorporation of 32P into ATP accompanied by enhanced or reduced respiration. In all cases MCPB was found to be more toxic than MCPA. These results are explained on the basis that ATP is the energy source for phosphate uptake and that a reduction in ATP synthesis with MCPA and MCPB results in lowered phosphate uptake.
Effectiveness of the (+)‐trans‐chrysanthemic acid ester of (±)‐allethrolone (bioallethrin) against four insect species
Authors: Davies Mary S. , Chadwick P. R. , Holborn J. M. , Stewart D. C. , Wickham J. C.
Published: November 2006

The activity of the (+)‐trans‐chrysanthemic acid ester of (±)‐allethrolone (Bio‐allethrin) is shown to be superior to that of the (±)‐cis, trans‐isomers (allethrin), against houseflies, two species of grain beetle and larvae of the yellow fever mosquito. The efficiency of the (+)‐trans‐isomer compares favourably with that of pyrethrins when each is used alone or with piperonyl butoxide.
Residues of tetrachlorvinphos and its breakdown products on treated crops. III.—Residues on a range of field crops
Authors: Beynon K. I. , Edwards M. J.
Published: November 2006

A wide range of crops including top fruit, cereals, brassicas, root vegetables and cotton from field trials in several countries in 1965, 1966, 1967 and 1968 have been analysed for residues of tetrachlorvinphos (Gardona, trans‐homer of dimethyl 1‐(2′,4′,5′‐trichlorophenyl)‐2‐chlorovinyl phosphate) foliar insecticide, its isomer and its potential breakdown products.

The residues under field conditions were mainly of tetrachlorvinphos, its isomer and 1‐(2′,4′,5′‐trichlorophenyl)ethan‐1‐ol in free and sugar‐conjugated forms. Tetrachlorvinphos was not unduly persistent on the crops and its initial half‐life varied from 2 days on cabbage, to 7 days on potato foliage and to 12 days on pears (after the last of five applications). From one week after the final application onwards the highest residues of tetrachlorvinphos observed were on olives (1 ppm after 18 days after a single application of 0·1 % active material), maize leaf (2·8 ppm at 9·5 weeks after the last of two applications at 3 kg/ha), and cabbage (1·9 ppm at 12 days after the last of three applications at 0·5 kg/ha). The maximum residues of the alcohol in the free form were 3·2 ppm on maize leaf at 8 weeks from the second application at 1·5 kg/ha and in the conjugated form were 1·0 ppm on cauliflowers at 6 days after the last of four applications at 0·5 kg/ha.
Determination of aminozide residues in chrysanthemum tissues
Authors: Dicks J. W.
Published: November 2006

A method initially developed for aminozide [succinic acid mono (2,2 dimethylhydrazide)] determination in apple fruit, involving hydrolysis to unsymmetrical dimethylhydrazine and oxidation of the latter to form aldehyde, has been adapted for use with chrysanthemum tissues. Modifications include preparation of the standard curve from aminozide samples taken through the entire procedure, use of a smaller sample size routine concentration of distillates containing unsymmetrical dimethylhydrazine on a rotary evaporator to remove interfering volatile material and correction for low levels of ‘apparent aminozide’ found in untreated tissue.
Determination of trichlorfon and fenthion residues in animals of different species
Authors: Möllhoff E.
Published: November 2006

Original results of analyses of residues of trichlorfon and fenthion and its metabolites following application of commercial products to cattle, sheep and pigs, together with results taken from the literature are compared. Despite the use of higher dose rates of trichlorfon, residues are lower than those of fenthion after dermal application. On the other hand, the residues of trichlorfon that occur in the animals following oral application briefly approach the theoretical maximum level in the tissues. The results are discussed in relation to the physical and chemical properties of the pesticides and their metabolites.
Control of wireworms with organophosphorus and carbamate insecticides
Authors: Edwards C. A. , Thompson A. R.
Published: November 2006

Carbaryl, chlorfenvinphos, diazinon, disulfoton, parathion, phorate, fenitrothion, thionazin and trichlorphon were tested for their effectiveness in killing wireworms by broadcast treatments. Each insecticide was tested once or more in two field trials cropped with wheat and two cropped with potatoes. Phorate and parathion were very lethal to wireworms at 4 Ib active ingredient per acre (4–48 kg/ha). Thionazin and diazinon were intermediate in effectiveness and the other insecticides ineffective.
Some studies on the systemic activity of the thiophanate fungicides in plants
Authors: Mercer R. T.
Published: November 2006

Three closely related fungicides, thiophanate (NF 35), thiophanate methyl (NF 44) and NF 48 have been found to be active against a wide range of diseases including the powdery mildews of apple, cucumber and barley; apple and pear scab and grey mould of soft fruit. This paper deals with the preliminary experiments to compare their relative mobilities and biological persistence in crop plants, using the powdery mildews as indicator infections.

NF 44 and NF 48 in particular showed a high degree of systemic activity by root uptake and persistence of action against barley and cucumber mildew but very little systemic activity against apple mildew on potted rootstocks. They have also displayed trans‐laminar and localised movement towards the leaf apex in sprayed cucumber and barley leaves but movement was not so marked in sprayed apple leaves.

NF 48 was also active as a seed dressing against loose smut of barley.
Selective herbicidal activity of iodide in relation to iodide accumulation and foliar peroxidase activity
Authors: Mynett A. , Wain R. L.
Published: November 2006

The response of several plant species (dwarf bean, tomato, pea, cabbage, nettle and buttercup) to treatment with iodide has been investigated. Selective toxicity of iodide has been confirmed, sensitive species exhibiting severe desiccation of the leaves.

Iodination of cellular components following treatment of bean leaves with iodide has been demonstrated, indicating that the iodide undergoes intracellular oxidation to iodine. This is thought to be brought about by peroxidase enzymes. Peroxidase activities (in relation to iodide oxidation) in the leaves of the plants studied have been determined. Although very low peroxidase activities are correlated with iodide tolerance, the results obtained indicate that the extent to which iodide accumulates in the leaves is also an important contributory factor in iodide selective toxicity.
The pyrethrins and related compounds. XIII. Insecticidal methyl‐, alkenyl and benzyl‐substituted furfuryl and furylmethyl chrysanthemates
Authors: Elliott M. , Janes N. F. , Pearson B. C.
Published: November 2006

3‐Furylmethyl and furfuryl chrysanthemates with methyl, benzyl, substituted benzyl and alkenyl substituents, and other heterocyclic analogues of these compounds, are synthesised for structure‐insecticidal activity investigations.
Persistence of some organophosphorus insecticides in hen‐house litter
Authors: Galley D. J.
Published: November 2006

Thin‐layer chromatography was used to assess semi‐quantitively the persistence of six organophosphorus insecticides in hen‐house litter. Malathion disappeared within 4 h of application. Carbofenthion was the most persistent. Four weeks after treatment the proportions of the applied doses extracted from the litter were: carbofenthion 46%, phorate 21%, diazinon 13%, coumaphos 7% and fenitrothion 3%.
Mode of entry of oxime carbamates into insects
Authors: Gerolt Ph.
Published: November 2006

The outcome of our earlier work suggested that the transport of contact insecticides into insects does not involve the haemolymph, but that the chemical probably reaches the internal organs by migrating in and/or over integumental tissue. This applies to various insects having quite different integumental organisation, and to various groups of insecticides differing widely in physical and chemical characteristics.

The present work has shown that carbamates (1‐alkylthioacetaldoxime carbamates) with high water solubility are no exception. The permeability of the body wall of the housefly for the methyl homologue (methomyl) which is the most water‐soluble of the series, although relatively high, is not high enough to account for the toxicity of the compound if it followed the haemolymph route. Methomyl when injected with water instead of an organic solvent was also found to be less toxic than the equivalent amount topically applied.

Lateral migration in the integument could be demonstrated with all the carbamates tested and dissimilarities in rates were apparent. Methomyl migrated the most rapidly and the cyanomethylene homologue the most slowly. Differences in mobility may be partly responsible for inequality in toxic effect, but it is thought that metabolic detoxication is of over‐riding importance.
Fumigation with methyl bromide II. Equipment and methods for sampling and analysing deep field soil atmospheres
Authors: Kolbezen M. J. , Abu‐el‐haj F. J.
Published: November 2006

Procedures were developed for the rapid sampling of deep soil atmospheres in the field and analysing them by gas chromatography. The methods described here have been used in studies on the diffusion of methyl bromide in relation to the control of Armillaria mellea.
Uptake and movement of paraquat in cocksfoot and wheat as influenced by surfactants
Authors: Brian R. C.
Published: November 2006

Surfactants are used to increase the efficiency of herbicide formulations mainly because they wet out leaf surfaces, thereby stabilising and increasing the contact area of droplets on the surface. Herbicide penetration through the cuticle may also be facilitated.

The work described eliminates effects on wetting and contact area in order to study the effect of surfactants on the penetration and movement of paraquat in cocksfoot. Surfactants were various types of alcohols and amine oxides condensed with 2 to 30 moles of ethylene oxide used at 0.1 to 0.5%. An adult leaf of cocksfoot (Dactylis glomerata) was immersed briefly to constant area in paraquat solutions containing surfactant and uptake and movement of paraquat is recorded.

Uptake was little affected by differences in surfactant structure except where surface activity was low and solutions failed to wet out the leaf surface. Percentage movement with 0.5% surfactant was often less than that with 0.1% and a high ethylene oxide content also reduced percentage movement. Paraquat activity was influenced by both the degree of uptake and movement, but movement was the greater influence.

Amine oxide surfactants reduced movement less than those based on alcohols. The action of surfactants is discussed in terms of a hydrophobic/hydrophilic balance in the surfactant molecule.
A new screening procedure for detecting plant growth regulating compounds
Authors: Brown B. T.
Published: November 2006

The crucifer Arabidopsis thaliana has been developed as a convenient screening plant to detect synthetic plant growth regulating substances. The plants are grown on nutrient agar in which the compounds to be screened are incorporated. The plants have been shown to exhibit a wide variety of responses to known plant growth regulators, which were not only qualitatively apparent, but could be quantitatively assessed. The rapid growth, small size and uniformity of the plants enables any changes in their lifecycle, from germination through growth, flowering and senescence, to be observed.
Gas chromatographic residue method for iodofenphos and two of its metabolites in animal tissues, fat and milk
Authors: Burkhard N. , Voss G.
Published: November 2006

A gas chromatographic residue method for use on animal tissues, fat, and milk is presented for the organophosphorus insecticide iodofenphos. The procedure includes the determination of two potential metabolites, iodofenoxon, and 2,5‐dichloro‐4‐iodophenol. The two phosphorus‐containing compounds are analysed by means of a flame photometric detector after cleanup including silica gel column and thin‐layer chromatography. The substituted phenol is determined separately as the acetylated derivative using an electron capture detector. Some information on the problem of specificity with regard to possible interferences by closely related insecticides or their corresponding phenols is also given.
The mobility of some organophosphorus sheep dip insecticides in soil
Authors: Inch T. D. , Ley R. V. , Utley D.
Published: November 2006

The technique of soil thin‐layer chromatography has been adapted to permit the use of repeated or prolonged irrigation procedures so that the mobility characteristics of relatively non‐mobile insecticides may be studied. The procedure has been used to study the relative movement of organophosphorus insecticides such as chlorfenvinphos, trithion, delnav and dichlofenthion which are widely used as sheep dips.
The influence of additives on the penetration of foliar applied growth regulator herbicides
Authors: Turner D. J.
Published: November 2006

The possibilities are demonstrated of increasing the activity of foliar applied growth regulator herbicides by mixing them with chemicals which injure the cuticle or epidermis.

S, S, S‐Tributyl phosphorotrithioate (“DEF”) increases the effects of picloram, 2,4,5‐T and mecoprop salts on four woody species, privet (Ligustrum ovalifolium Hassk.), poplar (× Populus gelrica Ait.), bluegum (Eucalyptus globulus Labill.) and guava (Psidium guajava L.). Mixtures with esters of the herbicides are not synergistic and often antagonistic.

DEF, tributyl phosphorotrithioite, a number of alkyl and aryl phosphates and phosphites and potassium ethyl xanthate enhance the phytotoxicity of picloram solution on dwarf bean (Phaseolus vulgaris L.). Mixtures of picloram with tributyl phosphorotrithioite, tributyl phosphate, mixed acid butyl phosphates, trimethyl phosphate and mixed isomers of tritolyl phosphate are synergistic when applied to guava foliage. Tributyl phosphate and mixed acid butyl phosphates interact similarly with picloram on privet and tributyl phosphate increases the effects of foliar applied mecoprop salt on guava.

The mode of action of the additives is not fully understood but there is evidence that DEF facilitates the entry of water soluble growth regulator herbicides into leaves and has little effect on the rate at which the herbicides move through the plant.

Tributyl phosphate and mixed acid butyl phosphates are suggested for practical use in herbicide formulations to control woody plants, as they are relatively cheap and non‐toxic.
The effect of processing in lowering the BHC residue in green leafy vegetables
Authors: Visweswariah K. , Jayaram M.
Published: November 2006

Investigations conducted on certain varieties of green leafy vegetables revealed very high BHC residues. The significance of certain common processing techniques in reducing the pesticide residue level on the raw material was investigated. Cooking the material in water for 5 minutes and immersion of the sample in 1% acetic acid solution and subsequent cooking reduced the level of pesticide residue within the permissible limit.
The phytotoxicity of some methylphosphonofluoridates
Authors: Howells D. J. , Hambrook Joy L.
Published: November 2006

The phytotoxicity of some O‐alkyl methylphosphonofluoridates has been studied by examining the effects of the compounds and their likely breakdown products on the germination of wheat seed and on the growth of wheat seedlings (14 to 18 days old) in hydroponic culture. The four O‐alkyl methylphosphonofluoridates (ethyl; isopropyl; 3,3‐dimethylbut‐2‐yl(pinacolyl) and cyclohexyl) were found to be phytotoxic and the phytotoxicity was shown to be a property of the compounds as such and not of their breakdown products. The phytotoxicity of the phosphonofluoridates was apparently influenced by the nature of the O‐alkyl group and tended to increase as follows: ethyl <isopropyl < pinacolyl <cyclohexyl.
The determination of thiabendazole (2‐(4‐thiazolyl)‐benzimidazole) in citrus fruit dips
Authors: Holmes M. Glennie
Published: November 2006

Methods for analysing the strength of thiabendazole (TBZ) dipping fluids are described. The methods which require only the minimum laboratory facilities and can be used in citrus packing houses, are based upon (i) a titration method utilising the complex formed by TBZ with silver ions, for accurate work, and (ii) a refractive index method after concentration for rapid checking by packing house employees. These methods are compared with a spectrophotometric method.
Antisporulant activity of 8‐hydroxyquinoline and its 5‐ and 6‐n‐alkyl derivatives against Gloeosporium fructigenum berk
Authors: Sneh B. , Clifford D. R. , Corke A. T. K.
Published: November 2006

The antisporulant activities of 8‐hydroxyquinoline (oxine) and members of the homologous 5‐ and 6‐n‐alkyloxine series against Gloeosporium fructigenum at varying ambient pH values and in the presence or absence of added Cu2+, Zn2+ and Fe2+ are described. Whilst changes in the pH value only influenced the antisporulant activity of oxine at low concentrations, lowering the ambient pH increased considerably the activities of the 5‐ and 6‐alkyl isomers at all concentrations. Below pH 7.0 the addition of these ions to the oxines resulted in decreased antisporulant activity (Fe2+ > Zn2+ > Cu2+) whereas, at pH 8.0, the addition of Cu2+ increased the activity of some oxines. It is suggested that at low pH (3.2) the oxine cation is an important toxicant.
The uptake of [14C] dieldrin via the roots of young cotton plants
Authors: Kavadia V. S. , Phillips F. T.
Published: November 2006

The stems and leaves of young cotton plants growing in nutrient solution containing a radioactive dieldrin suspension became radioactive. After 2 weeks, dieldrin was taken up at a constant rate which differered slightly in different environments probably because the plants transpired at different rates.
Residues of chlorpyrifos in various crops II. Residues after field treatments
Authors: Maini Paolo , Collina Arrigo , Passarini Ireneo
Published: November 2006

Five agricultural crops were treated with OO‐diethyl O‐(3,5,6‐trichloro‐2‐pyridyl) phosphorothioate (chlorpyrifos) granular or emulsifiable concentrate formulations at dosages from 0.5 to 6.0 kg (a.i.)/ha and at different periods before harvest. Chlorpyrifos residues were determined by gas chromatography after extraction and sweep co‐distillation clean‐up. Low residue levels were found. The average values in lettuce were 0.046 and 0.070 part/million, in sugar beet leaves 0.037 to 0.128 part/million and roots <0.005 to 0.038 part/million; no chlorpyrifos was detected in carrots, potatoes and cured tobacco leaves at the limit of the method (0.005 part/million).
Interactions between organophosphorus compounds and soil materials I. Adsorption of ethyl methylphosphonofluoridate by clay and organic matter preparations and by soils
Authors: Hayes M. H. B. , Lundie P. R. , Stacey M.
Published: November 2006

Data for the adsorption of ethyl methylphosphonofluoridate from aqueous and the vapour phases onto montmorillonite and kaolinite clays, onto soil organic matter preparations, and onto a limited number of soils are reported. These show that the phosphonofluoridate was absorbed from the vapour phase onto the dry clay preparations by physical‐chemical forces but was not adsorbed by the organic soil materials. In a general way adsorption onto dry soils could be related to their clay contents when the organic matter contents were low. Water was found to compete effectively with the phosphonofluoridate for adsorption sites, and it is concluded that this molecule will be most effectively retained by dry soils low in organic matter and rich in clay. Mechanisms for its adsorption onto clays are discussed.
The control of solute movement into sieve elements
Authors: Peel A. J.
Published: November 2006

A review is given of work on the movement of solutes into sieve elements, particularly with regard to investigations in which sieve tube exudate is obtained via the severed stylets of the aphid Tuberolachnus salignus (Gmelin), sited on bark strips or stem segments of willow.

Evidence is given showing that the uptake of naturally occurring solutes is an active and highly selective process, thus the rate of uptake is governed not by differences in concentration between the sieve tube and the source cells, but by “potential” gradients. It is pointed out that the phenomenon of selectivity by the sieve tube cannot yet be explained, though experiments are described which indicate the site of selection to be the tonoplast of the source cells, at least in the case of sugars.

Calcium is generally considered to be a rather phloem‐immobile cation. Evidence is given which demonstrates that a factor determining the immobility of this substance may be its inability to enter the sieve elements.

Some data are provided on the movement of certain synthetic growth regulators and herbicides into the sieve elements of willow. These were found to be loaded within a short time from their application to the cambial surface of bark strip. It is suggested that their ability to move into sieve elements is brought about by competition with naturally occurring solutes.

The conclusion is reached that investigations on solute loading are probably of more practical importance than those on the mechanism of longitudinal transport, since the control of the overall rate of transport may be in the former, rather than the latter, process.
Determination of nitroxynil in milk and dairy products
Authors: Parnell M. J.
Published: November 2006

Methods are described for the determination of nitroxynil (4‐cyano‐2‐iodo‐6‐nitrophenol) in milk and dairy products. The final estimation is made by direct current polarography.
Plant growth substance action on lecithin and lecithin/cholesterol vesicles
Authors: Kennedy C. D. , Harvey J. M.
Published: November 2006

The adsorption of some plant growth regulating compounds onto lecithin and equimolar lecithin/cholesterol vesicles and the effect of these substances on the rate of chloride/nitrate and sodium/potassium ion exchange across the vesicular membranes have been examined.

On comparing the binding of 2,4‐D, 2,6‐D, 2,4,5‐T and IAA to lecithin vesicles in solution at various pH values it is found that the unionised form of these acids is bound very much more strongly than the ionised form. Compounds having relatively low oil/water partition coefficients such as 2,4‐D, 2,6‐D and 2,4,5‐T are adsorbed onto vesicles, from solutions containing equimolar equilibrium concentrations of the unionised molecules, to markedly different extents (depending on the structure of the lipophilic portion of these molecules). Where the oil/water partition coefficient is higher, as for 2,4‐dichlorophenol and 2‐(2,4‐dichlorophenoxy)ethanol, binding to vesicles may also arise due to non‐specific solution within the hydrocarbon region of the lipid bilayers. The affinity of these compounds for lecithin has also been assessed by noting the extent to which the inclusion of lecithin in the oil phase increases the oil/water partition coefficient. This has shown that affinity for lecithin depends on the structure of both the lipophilic and hydrophilic portions of the molecule.

Only the unionised form of the compounds examined had any large effect on ion flux across the vesicle membranes. Significant increases in the rate of chloride/nitrate exchange were obtained on introducing quite high concentrations (0.015 to 1.5 mM) of the compounds 2,4‐D, 2,6‐D, 2,4,5‐T, IAA, and 2,4‐dichlorophenol, but not 2,4‐dichlorophenoxyethanol, to suspensions of lecithin vesicles. Similar flux increases were observed with lecithin/cholesterol vesicles except that more pronounced effects on flux were obtained on adding 2,4‐dichlorophenol and 2,4‐dichlorophenoxyethanol. In contrast 2,4‐D, 2,6‐D, 2,4‐dichlorophenol and IAA had no significant effect on the rate of Na+/K+ ion exchange across lecithin vesicles although increases were observed with equimolar lecithin/cholesterol vesicles.

Interpretations of these phenomena are suggested and their relevance to plant growth substance effects at the plasmalemma membrane discussed.
An assessment of the consequences of the controlled release of pesticides from granular formulations
Authors: Osgerby J. M.
Published: November 2006

The value of an analytical approach to the assessment of the advantages resulting from the use of controlled release granular formulations of pesticides is discussed. The methods are illustrated by considering the concentration‐time profiles resulting from the application of such formulations to water and to soils. The importance of the particular environment in which these formulations are used and of the dynamic nature of the pest population is emphasised. It is concluded that relatively simple controlled release granular formulations could give improvements in the performance of pesticides compared with conventional formulations but that the practicality of producing such formulations with a sufficiently large range of release rate constants is uncertain. Equally their use under field conditions might be subject to practical difficulties.
Effects of placement and distribution on the performance of granular formulations of insecticides for carrot fly control
Authors: Wheatley G. A.
Published: November 2006

Effects of granule distribution relative to carrot rows are discussed and further results described. Placing insecticides 5 to 10 cm deep 7.5 cm away from the centre line of the carrot row usually, but not always, improved their performance compared with bow‐wave applications. Both sides of the row need to be protected. The efficiency of chlorfenvinphos in a sandy loam, and phorate in a peaty‐loam, decreased with increasing distance from the row but they were slightly effective even 19 cm away. The optimum depth for side‐placing granules at sowing time varied from 5 to 10 cm, and combining side‐placement with a bow‐wave application did not greatly enhance efficiency. The most effective combination on a peaty‐loam was a bow‐wave application of 3 kg phorate/ha at sowing time followed 6 to 9 weeks later by a similar amount side‐placed 7.5 cm deep 7.5 cm from the row centre. Comparison of the performance of phorate broadcast, applied by the bow‐wave method or deep side‐placed indicated that efficiency was improved by restricting the granule distribution but that higher concentrations of granules were then needed in the treated zones to be equitoxic with more uniformly broadcast granules. Uptake by the carrot root system is an important factor in the action of insecticides against carrot fly larvae.
Pesticide residues in foodstuffs in Great Britain: A further report on the bromide contents of imported foods and feedingstuffs
Authors: Hill E. G. , Thompson R. H.
Published: November 2006

Results are presented for the determination of total bromide residues in cereals and cereal products, pulses, oilseed products, dried fruits, nuts and a variety of other products sampled in Britain during the 3‐year period July 1968 to June 1971. Of the 948 samples examined 801 (84%) contained not more than 100 mg/kg. bromide while only 20 samples (2 %) contained more than 200 mg/kg bromide. The highest residues were found in samples of nuts from India, South Africa and some East African countries and in some animal feedingstuffs.
Comparative tolerance of some dicotyledons to pronamide and chlorpropham
Authors: Roberts H. A. , Ricketts Margaret E.
Published: November 2006

In laboratory tests with 115 species of dicotyledons, the concentration of pronamide in water for 50% inhibition of root elongation ranged from 0.03 to >8 parts/million. With certain exceptions, species within a family responded similarly. Polygonaceae and Caryophyllaceae were the most susceptible and Compositae the most tolerant, as they were also to chlorpropham. There was good correspondence between the test results and the relative susceptibility of species to pre‐emergence application in the field.
The effect of benomyl and some related compounds on Lumbricus terrestris and other earthworms
Authors: Stringer Austin , Wright Michael A.
Published: November 2006

Earthworm populations in apple orchard plots sprayed with benomyl and thiophanate‐methyl were greatly reduced. Lumbricus terrestris, a surface‐feeding species, was not found in the treated plots. Captive worms would not feed on leaf material with spray deposits of benomyl, MBC and thiophanate‐methyl at 1.75 μg/cm2, and feeding was significantly reduced when deposits were 0.87 μg/cm2. There was 100 % kill of worms in pots of soil within 14 days following a benomyl drench at the rate of 7.75 kg/ha, and a 60 % kill following a drench at the rate of 1.55 kg/ha. Worms immersed for 1 min in benomyl suspensions of 0.05 or 0.5 % died within 27 and 13 days respectively; those immersed in lower concentrations would not feed for 2 weeks but eventually did so. It is suggested that the lethal effects of benomyl may be due to anti‐cholinesterase activity of the carbamate moiety of the molecule.
Derivatives of N‐(pyrid‐2‐yl)thiourea as root growth inhibitors
Authors: Brown B. T. , Harris R. L. N.
Published: November 2006

N‐Benzoyl‐N'‐(3‐methylpyrid‐2‐yl)thiourea has been shown to inhibit the elongation of linseed roots grown on nutrient agar, 50% inhibition being observed at a concentration of 0.18 μ. Similar effects were observed at higher concentrations on lettuce, ryegrass, cress, tomatoes and mustard. The effects were qualitatively similar to those caused by trifluralin. A structure‐activity study of analogues of this pyridyl thiourea indicates that structural requirements for this biological activity are extremely specific. In soil tests, this compound exhibits pre‐emergent herbicidal activity with a spectrum of selectivity different from that of trifluralin.
Gas chromatographic method for the residue analysis of soil exposed to fenazaflor
Authors: Whiteoak Roger J. , Crofts Michael , Harris Richard J.
Published: November 2006

A method is described for routine determination of residues in soil of 5,6‐dichloro‐2‐trifluoromethylbenzimidazole, the major product formed in soil from the acaricide fenazaflor. The residue is extracted from moistened soil with acidified aqueous methanol. After clean‐up by partition the residue is determined by g.l.c. with electron capture detection.

Details are presented of the investigations which led to the adoption of this procedure in preference to other variations.
Bacteria and protozoa in the rhizosphere
Authors: Darbyshire John F. , Greaves Michael P.
Published: November 2006

The origin and a modern interpretation of the term “rhizosphere”, the zone of soil close to plant roots, are discussed with special reference to soil bacteria and protozoa. The physical, chemical and biological factors which are known to influence the rhizosphere populations of these microbes are briefly considered. Root exudates and electronmicrographs of roots are discussed in relation to microbial ecology.
Some observations on microbial populations and nitrogen in soils infested with the take‐all fungus
Authors: Pearson Vivienne , Brown Margaret E. , Hornby David
Published: November 2006

Some possible causes of “take‐all decline”, the decrease in the severity of attack by Gaeumannomyces graminis on cereals after several years' consecutive culture, are discussed. The possible relationships between the NO3−–N:NH4+–N ratio in the rhizosphere, populations of rhizosphere bacteria and the incidence of take‐all are considered.
A simple laboratory spray method for use in crop protection research with special reference to ULV practice
Authors: Koopmans M. J. , Balk W.
Published: November 2006

A concise description is given of a method suitable for laboratory tests of crop protection agents, based on handspraying by means of a perfected spraying apparatus.

The dosage range is very wide, and the method is in fact applicable even in the ULV field.
Progress in research on resistance in arthropods
Authors: Busvine James R.
Published: November 2006

This is a short review of the history of the extensive research on resistance in the post‐DDT era, in relation to advancing experimental technique. The subject began as a serious concern to applied entomologists only, gradually involved other disciplines, notably genetics and biochemistry; and the inherent interest and challenge of the problem attracted the attention of experts in these fields. It will be convenient to divide the 25 years involved into three periods: the years up to 1952, the decade 1953‐62 and the decade 1963‐72. The various types of investigation can be categorised as: (1) detection and measurement, (2) genetic studies, (3) primary toxicology and (4) biochemical toxicology.
Studies of the adsorption of paraquat on soluble humic fractions by gel filtration and ultrafiltration techniques
Authors: Burns Ian G. , Hayes Michael H. B. , Stacey Maurice
Published: November 2006

The adsorption of paraquat dichloride (1,1′‐dimethyl‐4,4′‐bipyridylium dichloride) on a soluble sodium humate fraction of a Fenland soil was studied by gel filtration (on Sephadex G10 and G100) and by ultrafiltration (through an Amicon Diaflo UM‐2 ultrafilter). Both methods depend upon the separation, on a molecular weight basis, of the unadsorbed molecules of herbicide from the adsorption complex (consisting of polymeric organic materials and the adsorbed paraquat). Separations were obtained on columns of Sephadex G10 (Method I) and in the ultrafiltration experiments (Method II), and isotherms were prepared from data for adsorption in water (by Method II) and in sodium chloride (by Methods I and II) solutions. Results from the two methods were comparable over the concentration range examined. The increased adsorption of paraquat by Na+‐compared with Ca2+‐humate is explained on the basis of the selectivity sequence of humate for exchangeable cations. Attempts to prepare isotherms from gel filtration data, for the adsorption of paraquat on two soluble model humic polymers (polyacrylic acid and a polymer prepared by the oxidative coupling of benzoquinone and ammonium chloride) were unsuccessful because binding to the gel matrix did not permit quantitative recoveries of the adsorption complexes.

Paraquat was adsorbed to the same extent on each of four fractions of Na+‐humate separated on Sephadex G100.
Effects of the herbicide methabenzthiazuron on the physiology of wheat plants
Authors: Fedtke Carl
Published: November 2006

Spring wheat (Triticum aestivum L. “Caribo”) was grown in vermiculite containing methabenzthiazuron (N‐(benzothiazol‐2yl)‐NN′‐dimethylurea) presowing. Effects of the herbicide on plant development and plant composition were analysed up to an age of 4 weeks.

Inhibition of photosynthetic oxygen evolution represented the primary effect induced by the herbicidal treatment and led to a decreased concentration of soluble reducing sugars. Photosynthetic activity however recovered after 3 weeks and even increased above control values. Secondary effects following methabenzthiazuron treatment included a delayed chlorophyll breakdown, a decreased chlorophyll a/b ratio, enlarged chloroplasts, an increased concentration of soluble amino acids and of soluble protein, and an increased in vitro nitrate reductase activity. These responses are taken to indicate an increased photosynthetic and metabolic capacity in methabenzthiazuron treated wheat plants.

Comparable results can be obtained with plants grown at low light intensities. It is concluded that the “physiological effects” observed in wheat plants after treatment with methabenzthiazuron are similar to a natural adaptation reaction to low light intensities. It is assumed that this adaptation reaction is caused by a low concentration of soluble reducing sugars.

Experiments with plants growing at different light intensities indicated that effects due to herbicidal action were more pronounced at high light intensities.

Measurements on daily fluctuations revealed a peak around noon for the sugar content and the nitrate reductase activities measured in vivo as well as in vitro. In vivo nitrate reductase activity in plants treated with 5 parts/million methabenzthiazuron was very low, presumably because of lack of sugars for the production of NADH. The protein concentration was increasing and the amino acids were decreasing during the day in herbicide treated plants, possibly indicating increased protein synthesis in the light in plants treated with methabenzthiazuron.
Effect of time of irrigation on the distribution of 1,2‐dibromo‐3‐chloropropane in soil after shallow injection
Authors: Hodges L. R. , Lear Bert
Published: November 2006

The effect of irrigation time on the dispersion of 1,2‐dibromo‐3‐chloroproparie (DBCP) in soil after a shallow injection treatment was determined for Yolo fine sandy loam. When injections equivalent to 23.5 litres of DBCP/ha at a depth of 7 to 8 cm were subsequently followed by 15 cm of irrigation water, adequate distribution of DBCP was obtained if the soil was irrigated within 5 days. However, the most rapid and deepest penetration of fumigant was obtained by irrigating 2 to 5 days after application. There was insufficient downward movement of DBCP in non‐irrigated soil.
Insecticide trials for the control of the false codling moth, Cryptophlebia leucotreta Meyrick (Lepidoptera: Tortricidae; subfamily olethreutinae)
Authors: Nyiira Zerubabel M.
Published: November 2006

Parathion‐methyl and monocrotophos at 1.12 kg active material/ha at intervals of 10 and 5 days, respectively, suppressed larval populations of the false codling moth, Cryptophlebia leucotreta Meyrick (Lepidoptera: Tortricidae) in cotton bolls. The use of parathion‐methyl is not recommended in Uganda because of its high oral and dermal LD50 of 12 to 16 mg/kg and 67 mg/kg, respectively, on rats. Although comparatively, monocrotophos has a high oral LD50 of 20 mg/kg, it has a reasonable dermal LD50 of 342 mg/kg and can, in practice, be handled by peasant farmers if well instructed.
Bromine residues in potato and wheat crops grown in soil fumigated with methyl bromide
Authors: Brown George , Corbett Donald C. M. , Hide Geoffrey A. , Webb Robin M.
Published: November 2006

The bromine content of potato tubers grown in soil fumigated with methyl bromide at 487 and 975 kg/ha (1 lb and 2 lb/100 ft2) averaged 170 and 280 mg/kg of dry weight. Most of the bromine was in the outer layers of the tubers; peeled tubers has less than 100 mg/kg, which remained after boiling. Potato haulm contained 4000 or 6700 mg/kg bromine respectively for the two rates of application. The bromine content of wheat grain grown after potatoes depended on the rate of application of methyl bromide and the time interval between treatment and wheat crop. Wheat grain harvested 31/2 21/2 and 11/2 years after fumigation with methyl bromide at 975 kg/ha had mean bromine contents of 4.5, 15 and 44 mg/kg. but the amounts in grain from plots having the same treatments varied more than two‐fold; wheat grain harvested 11/2 years after fumigation at 487 kg/ha contained 23 mg bromine/kg. Wheat yields were unaffected by fumigation.
Insect problems in crops for processing
Authors: Wheatley G. A.
Published: November 2006

The differing motives of growers, processors and the public for controlling pests are discussed, and effects of changes in crop production systems are noted.

For each crop/pest/market problem, damage by particular pests has a unique importance and can be expressed as the frequency of occurrence of damaged crop produce (‘units’) and the amount of damage done to each. By reference to pests of vegetables, damage is classified according to whether it prevents the plant reaching maturity, or affects the unmarketed or the marketed part of the plant.

A distinction is made between the efficiency and the effectiveness of control measures. Their limitations and associated problems are also discussed.
Synthesis and structural studies of 9‐Anti‐hydroxy HEOD
Authors: Baldwin Michael K. , Porter Albert , Hayes William P. , Burns Duncan Thorburn
Published: November 2006

9‐Syn‐hydroxy HEOD, a major mammalian metabolite of HEOD was oxidised to the ketone which, on reduction with sodium borohydride, gave a product identified by spectrometric methods as 9‐anti‐hydroxy HEOD. This product was not converted to the pentachloroketone metabolite of HEOD, either by photolysis or metabolically by a rat.
The fate of some organophosphorus compounds applied topically to peach‐potato aphids (Myzus persicae (Sulz.)) resistant and susceptible to insecticides
Authors: Devonshire A. L. , Needham P. H.
Published: November 2006

The fate of [14C]‐dimethoate and [14C]‐parathion after topical application to strains of Myzus persicae resistant and susceptible to organophosphorus compounds was investigated. In 4 h approximately 65% of the dimethoate or para‐thion applied was lost from the aphids by evaporation, and this limited the amount available for penetration into the insect. Only approximately 25% of the dose applied penetrated, of which a very small proportion was excreted as metabolites. There was no difference in the amounts penetrating into the resistant and susceptible strains, indicating that penetration was not a factor contributing to the observed resistance. These findings emphasise that evaporation from the cuticle can greatly influence results when insecticides are applied topically.
The metabolism of carboxin in growing barley
Authors: Briggs Dennis E. , Waring Rosemary H. , Hackett Andrew M.
Published: November 2006

The major soluble metabolite of carboxin (2,3‐dihydro‐6‐methyl‐5‐phenylcarbamoyi‐1,4‐oxathiin) in barley seedlings and mature plants was identified as the‐hydroxy phenyl derivative. This phenol was also bound to the lignin fraction. The distribution of carboxin and its metabolites in seedlings and mature plants grown from treated seed was studied; maximum residues were found in the three oldest internodes, with traces in the roots and flowering heads. Treated plants had altered chlorophyll/carotenoid ratios, and raised levels of some free amino acids.
Dissipation of 4‐chloro‐2‐methylphenoxyacetic acid (MCPA) in a rice field
Authors: Soderquist Charles J. , Crosby Donald G.
Published: November 2006

The dissipation of the herbicide 4‐chloro‐2‐methylphenoxyacetic acid (MCPA) in a California rice field was investigated. Samples of water, rice plants and mud were collected at intervals for 20 days and analysed for MCPA by established methods for plants and mud, and by a novel method utilising XAD‐2 macro‐reticular resin for water. Water residues declined to less than 0.01 parts/106 of MCPA within 14 days after application; plant residues declined from 20 parts/106 to 1 part/106 within 20 days; mud residues remained constant at about 0.1 parts/106. Photolysis of dilute aqueous MCPA solutions with either sunlight or an indoor photoreactor yielded 4‐chloro‐2‐methylphenol as the major product; o‐cresol and 4‐chloro‐2‐formylphenol also were identified. While photosensitisation was observed with water taken from the rice field, microbial degradation proceeded at an even faster rate. All environmental compartments except air contained measurable amounts (>0.01 parts/106) at some time, but water contained the bulk of the applied MCPA whose eventual disappearance was shown to be due to biological and chemical degradation and not dilution.
Two improved methods for the determination of dinocap in fruits and vegetables
Authors: Johansson Carl E.
Published: November 2006

Gas chromatographic and spectrophotometric methods are described for the determination of dinocap extracted from apples, strawberries and cucumbers with organic solvents. The spectrophotometric method is based on the rapid hydrolysis of dinocap by means of ethanolamine. Qualitative confirmation of the presence of dinocap is performed by thin‐layer chromatography.
Effects of mode of testing on susceptibility to various insecticides of adults or larvae of Lucilia sericata, Chrysomya putoria and Musca domestica L
Authors: Busvine James R. , Iwuala Moses O. E.
Published: November 2006

Relative potency of eight compounds (four pairs of similar types) to adults and old larvae of three species of cyclorhaphous diptera was determined by injection, oral or topical application. The following points emerged from comparisons of equitoxic doses: (a) C. putoria was consistently more susceptible than L. sericata. M. domestica was more susceptible to organochlorines than either of the blowflies, but less susceptible to organophosphorus, carbamate or pyrethroid insecticides; (b) the most potent insecticides (bioresmethrin, diazinon) were about equally toxic to adults and larvae of all species; but some compounds (especially DDT, gamma‐BHC and propoxur) were relatively much less effective against larvae; (c) LD50 values for oral treatments were higher than by injection, and those for contact treatments higher still. These “penetration factors” were highly correlated within each of the stages. This could be due to similarity in the cuticular barrier and (or) detoxication; (d) experiments with various synergistic compounds showed higher synergistic factors for larvae than adults (with DDT, bioresmethrin and propoxur). This probably indicates a more efficient detoxication system in the larvae, which is consistent with findings (b) and (c).
Synthesis of potential organophosphorus fungicides. I. Diaryl dichloromethyl phosphonodithioates
Authors: Roy Nripendra K. , Mukerjee Sunil K.
Published: November 2006

The synthesis of five diaryl dichloromethyl phosphonodithioates and a novel substitution reaction of the trichloromethyl phosphonates is described. The new compounds prepared show only moderate activity in vitro against Pyricularia oryzae and poorer control of Helminthosporium oryzae.
Mechanism of transfer of insecticides in Musca domestica
Authors: Gerolt Philip
Published: November 2006

The onset of symptoms of toxicity in houseflies treated with poisons of the central nervous system (CNS) is shown to be delayed by measures which block metabolic activity such as depriving the insects of oxygen or decreasing the temperature. The indications from this work are that these measures also delay the penetration of the insecticide into the CNS. This suggests that the movement of the insecticide is mediated by a process which requires the expenditure of metabolic energy in a living tissue. The tissue most likely to be involved in insecticide transport is the epidermis.
A survey of sheep dip usage in Scotland, 1973
Authors: Cutler James R.
Published: November 2006

A survey of sheep dipping and spraying in Scotland during 1973 has shown that about 40 tonnes of organophosphorus, 8 tonnes of organochlorine and 2 tonnes of carbamate insecticides were used to control ectoparasites. Substances used to combat headfly (Hydrotaea irritans) and the main areas of Scotland affected by this pest are noted. Information about the pattern of dipping in relation to geographical area, season and flock size and about the disposal of surplus dip and empty containers is presented. Though a small potential for environmental damage still exists no evidence of such came to light.
Formulations for the control of dutch elm disease
Authors: Clifford Derek R. , Gendle Peter , Fribbins Edward A.
Published: November 2006

Solutions of methyl benzimidazol‐2‐ylcarbamate (carbendazim, formerly MBC) in dilute hydrochloric, orthophosphoric or hypophosphorous acid and in dilute hydrochloric acid containing methanol (“Lignasan”) and aqueous solutions of 2‐(thiazol‐4‐yl) benzimidazole (thiabendazole) hypophosphite, 8‐hydroxyquinoline (oxine)hydro‐chloride and dodecylguanidine acetate (dodine), were tested in the field for their efficacy in controlling Dutch elm disease caused by Ceratocystis ulmi. All gave some degree of control although some were phytotoxic, the benzimidazoles being the most active compounds tested. The anion and the concentration of acid present in the formulation may have some effect on retention of active material within the crown of the tree.