bluuebunny/crossref_metadata_2025 huggingface dataset:
The pyrethrins and related compounds. XIX Geometrical and optical isomers of 2,2‐dimethyl‐3‐(2,2‐dichlorovinyl)‐cyclopropanecarboxylic acid and insecticidal esters with 5‐benzyi‐3‐furylmethyi and 3‐phenoxybenzyl alcohols
Authors: Burt Paul E. , Elliott Michael , Earnham Andrew W. , Janes Norman F. , Needham Paul H. , Pulman David A.
Published: November 2006

Esters of 2,2‐dimethyl‐3‐(2,2‐dichlorovinyl)‐cyclopropanecarboxylic acid with appropriate alcohols are more active insecticides than the corresponding 3‐isobutenyl compounds (chrysanthemates). (±)‐Cis and (±)‐trans forms of the dichloro acid are obtained by fractional crystallisation of the mixed acids or by hydrolysis of the ethyl esters separated by fractional distillation. The (±)‐cis and (±)‐trans acids are resolved into their (+)‐ and (‐)‐forms with α‐methyl‐benzylamine and threo‐l‐p‐nitrophenyl‐2‐N,N‐dimethyiamino‐propane‐1,3‐diol respectively. As for the corresponding chrysanthemates, the (+)‐cis and (+)‐trans acids give esters more active as insecticides than their enantiomers.
Studies on the breakdown of p‐chlorophenyl methylcarbamate. I. In soil
Authors: Priest Bernard , Stephens Richard J.
Published: November 2006

The compound p‐chlorophenyl methylcarbamate (PCMC) was shown to inhibit the breakdown of the herbicide isopropyl 3‐chlorophenylcarbamate (chlorpropham) in soil, increasing its half‐life from 7.5 to 20 days. The inhibitory effect of PCMC on the breakdown of chlorpropham persisted for 40 days, with a half‐life of 20 days. The conversion in soil, of PCMC to p‐chlorophenol, a compound which did not affect the persistence of chlorpropham, was demonstrated, and it is suggested that spontaneous chemical hydrolysis may account for this conversion. PCMC and p‐chlorophenol were shown to be of low toxicity to buckwheat (Fagopyrum esculentum Moensch.).
Indirect polarographic determination of folpet
Authors: Seifert Josef , Davídek Jiři , Egertová Jarmila
Published: November 2006

Phthalimide, the reaction product of the interaction between folpet and L‐cysteine, has been determined polarographically and the method applied to the parallel determination of folpet and phthalimide impurities in commercial preparations and in the surface residues on strawberries and cotton seeds.
Accumulation and distribution of pp′‐DDT and related compounds in an apple orchard. II. Residues in trees and herbage
Authors: Stringer Austin , Pickard John A. , Lyons Clive H.
Published: November 2006

DDT residues in or on the roots and leaves of the herbage and the roots, bark, leaves and fruit of the trees are given for an apple orchard sprayed annually (1953–1969). The distribution of DDT in both the grass and the grass roots was in circular areas of residues, with maximum values at each trunk and decreasing radially to each alley. Of the spray applied at the green cluster stage 80% was deposited on the grass sward and very little, if any, directly on the soil surface. The pp′‐DDT content of the grass fell rapidly with successive mowings (from which the cuttings remained in situ) from 400 μg/g at spraying to 2 μg/g after nine months. 33 g/ha pp′‐DDT was found in the herbage roots (0.87% of the total residues in the soil). The residues in the bark (87.5 g/ha) were much lower than expected after 13 years spray application. There were increased amounts of pp′‐DDE, pp′‐TDE and pp′‐TDEE relative to pp′‐DDT, indicating some breakdown on the bark, but the chief losses were attributed to volatilisation and to removal by wind and rain. The residue content of root bark varied from 3 μg/g near the emerging trunk to 0.05 μg/g at a depth of 90 cm. The pp′‐DDT content of leaves at leaf fall rose from <1 ng/g after a single spring spray to 8.33 μg/g following an additional spray in late June. There was a large loss of DDT from the canopy between the June spray and leaf fall (440–480 g/ha down to 25 g/ha), attributed to volatilisation. The amount of pp′‐DDT on the fruit, after a single spray, was 3 ng/g fresh weight (80.9 mg/ha out of a total of 1.0–1.5 kg/ha used).
The development of flamprop‐isopropyl—A new wild oat herbicide for use in barley
Authors: Haddock Ernest , Jordan Donald , Sampson Alan J.
Published: November 2006

Flamprop‐isopropyl, isopropyl (±)‐2‐[N‐(3‐chloro‐4‐fluorophenyl)benzamido]‐propionate, has been shown to give good control of Avena spp. in barley. Results from glasshouse tests have been confirmed in field trials over two seasons, in 8 European countries, using a 200 g/litre formulation of the herbicide. In Spring barley the crop stage during which application should be made for optimum weed control and crop benefit lies between late tillering and the formation of the second node.
Structure‐activity relationships in fungitoxicants related to triforine and chloraniformethan. III. A quantitative hansch analysis
Authors: Brown David , Woodcock David
Published: November 2006

Quantitative structure‐activity relationships in several series of fungitoxic N‐(1‐substituted‐2,2,2‐trichloroethyl)formamides and bis[1‐(2,2,2‐trichloroethyl)formamides] were investigated by the Hansch method, employing partitioning data determined by reversed‐phase thin‐layer chromatography and electronic parameters calculated by the Hückel Molecular Orbital method. The activity of compounds applied as root‐drenches against Erysiphe graminis on barley correlated with their partitioning properties alone, but electronic properties of the aromatic derivatives were also influential in leaf‐spray tests. Possible factors governing the activity of the compounds are discussed. It is tentatively proposed that the biologically active centre of triforine and related aliphatic compounds includes the XCHNHCO grouping (where X = heteroatom), whereas that of chloraniformethan and its aryl analogues incorporates the grouping RXCHNHCO (where RX = a conjugated system capable of accepting pi‐electrons from an electron donating receptor).
Residues of DDT in cottonseed after spraying with DDT and torbidan
Authors: Zorgani Gaafer A El
Published: November 2006

DDT at 1.12 and 2.24 kg/ha a.i. and Torbidan at 5 and 10 litre formulation/ha (1 and 2 kg DDT/ha) were sprayed five times on cotton over a period of 15 weeks. Seeds from the first pick of the crop were found to contain as residues pp′‐DDT and pp′‐DDE [1,1‐dichloro‐2,2‐di‐ (4‐chlorophenyl)ethylene]. The highest residue level (0.783 parts/106) was found in seeds from Torbidan 10 litre/ha treatment.
Pest and disease control on intensive apple trees by overhead mobile spraying
Authors: Cooke Barry K. , Herrington Pamela J. , Jones Kenneth G. , Morgan Norman G.
Published: November 2006

In 3 year field experiments on pest and disease control by mobile overhead spraying of intensive Cox's Orange Pippin apple trees, overhead booms applying 1125 litres/ha and overhead mist‐blowing equipment applying 562 litres/ha, each spraying two complete rows from one alley in half the normal time, were compared with conventional automatic mast spraying at 2250 litres/ha and with conventional mist‐blowing at 562 litres/ha. The overhead boom application of demeton‐S‐methyl (0.0036% a.i.) with azinphos‐methyl (0.0165% a.i.) or of fenitrothion (0.031% a.i.) at the green cluster stage gave control of the applegrass aphid, Rhopalosiphum insertum, virtually equal to that obtained by conventional application of the same insecticides. Similarly, the overhead mist applications of conventional quantities of insecticides gave equal control, but not when applying one‐quarter of the normal amount of insecticides. The conventional methods generally gave better control of apple sucker, Psylla mali. In 1971, when the incidence of apple scab, Venturia inaequalis, was only moderate, the overhead boom method gave equal control to conventional spraying with both dodine/captan (0.03% a.i. and 0.094% a.i.) and benomyl (0.025% a.i.) programmes: in 1972 and 1973, when the scab incidence was heavier, the overhead boom spraying was again equal to the conventional method with the benomyl programme but was less effective with the dodine/captan programme. The overhead mist applications gave control only when the scab incidence was light. Repeated applications of dinocap emulsion (0.025% a.i.), included in the fungicide programme in 1971, gave as good control of the active stages of fruit tree red spider mite, Panonychus ulmi, when applied by the overhead methods as by conventional spraying, but application of the benomyl programme gave poor control. Mobile overhead spraying of small intensive apple trees is a promising method but needs further development before becoming fully acceptable.
Structure—activity relationships of fungicidal acetylenic sulphones
Authors: Selling Hendrik A. , Tempel Albert
Published: November 2006

Regression analysis in the l‐alkylsulphonyl‐2‐arylacetylene series yielded significant correlations of antifungal activity against six microorganisms with certain physicochemical parameters (electronic effects, lipophilicity and steric factors). Fungicidal activity is enhanced by introducing electron‐withdrawing substituents in the aryl nucleus, whereas variation of the lipophilic parameter reveals an optimum value. The results obtained indicate a mechanism of action based on a reaction of the compounds with nucleophiles present in the fungal cells, which was confirmed by determining the second‐order rate constants of the reaction between 1 ‐alkylsulphonyl‐2‐arylacetylenes and the model nucleophile 4‐nitro(thiophenol). The lipophilic para‐meter was also determined experimentally using thin‐layer chromatography. Regression analysis with this completely experimental set of parameters regression gave highly significant results in close agreement with those obtained above.
Pest and disease control with low doses of pesticides in low and ultralow volumes applied to intensive apple trees
Authors: Cooke Barry K. , Herrington Pamela J. , Jones Kenneth G. , Morgan Norman G.
Published: November 2006

In 3 year field experiments on the development of more economical methods for pest and disease control on intensively planted dessert apple trees, low dose applications of one‐tenth of the normal quantities of pesticide in one‐hundredth, one‐tenth and one‐fifth of the normal volumes were compared with conventional high volume spraying at 2250 litres/ha. An experimental tractor‐mounted mist blower, a motorised knapsack mist blower and a fan‐assisted disc sprayer were each used to apply the pesticides in 225, 45 and 22.5 litres of water/ha. Control of the apple‐grass aphid, Rhopalosiphum insertum, obtained by low dose spraying of demeton‐S‐methyl (8 g a.i./ha) combined with azinphos‐methyl (37 g a.i./ha) in 225 and 22.5 litres/ha in 1971 and of fenitrothion (70 g a.i./ha) in 225, 45 and 22.5 litres/ha in 1972 and 1973 was almost equal to that obtained by the conventional high volume method. Low dose applications of benomyl fungicide programmes gave poor control of apple scab, Venturia inaequalis in 1971 when the disease incidence on the fruit was very high at 73%, but in 1972 and 1973, when it was moderately high at 42–45%, control was almost equal to that given by the conventional high volume method. Under these conditions all the low dose methods gave better control with benomyl than with dodine/captan programmes.
Simulation of herbicide persistence in soil .I. Simazine and prometryne
Authors: Walker Allan
Published: November 2006

The effects of soil temperature and soil moisture content on the rates of degradation of simazine and prometryne were measured under controlled conditions. The time for 50% disappearance of simazine in a sandy loam soil varied from 37 days at 25°C and 13 % soil moisture to 234 days at 15°C and 7% soil moisture. With prometryne, changes in soil moisture content had a greater effect on the rate of loss than similar changes with simazine. The time for 50% disappearance at 25°C was increased from 30 to 590 days with a reduction in soil moisture content from 14 to 5%. With both herbicides, the rate of degradation increased as the initial herbicide concentration decreased and the data suggest that a hyperbolic rate law may be more appropriate than simple first‐order kinetics. Degradation curves for three separate field applications of the two herbicides were simulated using the laboratory data and the relevant meteorological records in a computer program. A close fit to the observed pattern of loss of incorporated prometryne was obtained, but prometryne surface‐applied was lost rapidly during the first 30–40 days after application. This initial rapid loss could not be predicted by the program. With simazine, the patterns of loss of surface and incorporated treatments were similar, but the simulation model tended to overestimate residue levels. Possible reasons for the discrepancies are discussed.
Synthesis and insecticidal and acaricidal properties of some 5‐methoxy‐1‐methyl‐6‐oxo‐1H‐pyridazin‐4‐yl phosphorus esters. III
Authors: Konečný Václav , Varkonda Štefan , Vargová Mária
Published: November 2006

A series of new 5‐methoxy‐1‐methyl‐6‐oxo‐1H‐pyridazin‐4‐yl phosphorus esters, which was prepared by phosphoroylation of 5‐methoxy‐1‐methyl‐6‐oxo‐1H‐pyri‐dazin‐4‐ol, is described. Many of the compounds showed high insecticidal and acaricidal activity.
Uptake, distribution and metabolic fate of 3H‐triforine in plants. II. Long‐term experiments
Authors: Fuchs Adriaan , De Vries Frits W. , Aalbers André M. J.
Published: November 2006

Uptake of 3H‐triforine by tomato and barley seedlings from soil with a high organic matter content was much less efficient than from aqueous suspensions, even though the period of exposure was much longer—at least 1 week (“long‐term treatment”) vs 1 day (“short‐term treatment”). After transplanting to fresh soil, part of the label in the roots was lost probably by desorption. Distribution of label in tomato shoots was as irregular as after short‐term treatment; label was virtually confined to the leaves which expanded before about 14 days after cessation of the treatment. In shoots of barley seedlings which were pretreated in an aqueous suspension of 3H‐triforine for 1 day before being subjected to a long‐term soil treatment, almost all radioactivity present could be ascribed to uptake during the pretreatment phase. The distribution pattern strongly resembled that obtained after short‐term treatment, hardly any label being found in leaves which unfolded after the pretreatment phase. Rates of conversion of 3H‐triforine in barley shoots depended to some extent on whether or not seedlings were transplanted to fresh soil after 1 week.
Degradation of the insecticide SD 8280, 2‐chloro‐1‐(2, 4‐dichlorophenyl)vinyl dimethyl phosphate, in soils
Authors: Roberts Terry R. , Stoydin George
Published: November 2006

The degradation of the insecticide SD 8280 [2‐chloro‐1‐(2,4‐dichlorophenyl)vinyl dimethyl phosphate] in soil has been examined under laboratory conditions using two soils from rice‐growing areas in Japan and one UK soil. In all soils SD 8280 underwent degradation to 1‐(2,4‐dichlorophenyl)ethanol, 2,4‐dichlorobenzoic acid, 2‐chloro‐1‐(2,4‐dichlorophenyl)vinyl methyl hydrogen phosphate and 2′,4′‐dichloro‐acetophenone. These degradation products were present in the soils as free (extractable) compounds and as bound forms and soil binding occurred most extensively with 2,4‐dichlorobenzoic acid. Polar products were also formed and these appeared to be in part the result of complexing of degradation products with the soil organic matter. The effect on the degradation of the insecticide of varying the moisture content of one soil was also examined. In soil incubated at 11, 17, 30 and 62% moisture the recovery of SD 8280 after 60 days was 71.0, 12.3, 9.0 and 11.3%, respectively. Although the rate of degradation varied, the same degradation products were detected in all samples.
Influence of artificial rainfall and washing on the benomyl and thiophanate‐methyl residue content in lettuce
Authors: Dejonckheere Willy , Steurbaut Walter , Kips René H.
Published: November 2006

Experiments have been carried out to investigate the influence of artificial rainfall, applied during the growing season of lettuce in a glasshouse, and washing of the sample prior to analysis on the residue content of the crop treated with the systemic fungicides benomyl and thiophanate‐methyl. The results show that if artificial rainfall is applied, treatment with a threefold dose of thiophanate‐methyl, compared to benomyl, results in about the same residue content at harvest time. Applying artificial rainfall during the growing season leads to a residue level on the average 54.7% lower for benomyl and 60.2% for thiophanate‐methyl compared to no sprinkling. If the sample is thoroughly rinsed with water prior to analysis the figures obtained are 34.6% with and 39.3% without artificial rainfall for benomyl and 56.9 and 71.3% respectively for thiophanate‐methyl. The combined effect of both treatments is a residue content of 70.4 % less for benomyl and 88.8 % for thiophanate‐methyl.
A new extraction method for benomyl residues in soil and its application in movement and persistence studies
Authors: Austin Douglas J. , Briggs Geoffrey G.
Published: November 2006

A simple and rapid method for extracting benomyl residues from soils was compared with previous methods. Soil was extracted by shaking for 2 h at room temperature with (1:1) acetone/M aqueous ammonium chloride followed by clean‐up by solvent partition and ultraviolet absorption estimation of carbendazim. Recoveries were comparable to those obtained by refluxing with methanolic hydrochloric acid for 4 h, hitherto the most efficient method reported, and were much greater than those obtained by extraction with ethyl acetate or chloroform. The new method gave more tractable extracts than those obtained by refluxing with methanolic hydrochloric acid, which form troublesome metal hydroxide precipitates during clean‐up. In field experiments with 2‐[14C]‐benomyl and 2‐[14C]‐carbendazim, no radioactivity was found more than 25 mm from the soil surface during 10 months after surface application of 1 kg/ha. Carbendazim residues in soils from three field experiments indicated that its persistence is very sensitive to soil pH. The time for 50% loss of initial dose ranged from 26 months at pH 5.5 to less than 3 months at pH 7.2. Biological effectiveness in a crop may therefore depend markedly on differences in soil pH.
2‐arylalkanoates, a new group of synthetic pyrethroid esters not containing cyclopropanecarboxylates
Authors: Ohno Nobuo , Fujimoto Keimei , Okuno Yoshitoshi , Mizutani Toshio , Hirano Masachika , Itaya Nobushige , Honda Toshiko , Yoshioka Hirosuke
Published: November 2006

Although structure modifications of natural pyrethrin constituents have disclosed a variety of potent synthetic analogues, all known examples are cyclopropanecarboxylate esters, a grouping that appeared to be essential for insecticidal activity. Some new substituted 2‐phenylalkanoates, whose biological activities are of a similar nature and potency to those of conventional pyrethroids, are now reported. 5‐Benzyl‐3‐furylmethyl and 3‐phenoxybenzyl 3‐methyl‐2‐phenylbutyrates and their analogues are potent insecticides. Activity is increased on the introduction of appropriate groups into the 3 and/or 4‐positions of the aryl ring and the (S)‐2‐phenylalkanoates are far more active than their (R)‐enantiomorphs. Structure/activity relationships are compared with those for conventional pyrethroids. Some of the new series compare favourably with typical insecticides in tests against Musca domestica, Spodoptera litura and Plutella xylostella.
RU‐15525, a new pyrethroid with a very strong knockdown effect
Authors: Lhoste Jean , Rauch François.
Published: November 2006

(E)‐5‐Benzyl‐3‐ furylmethyl (1‐R),3‐S)‐2,2‐dimethyl‐3‐(2,3,4,5‐tetrahydro‐2‐oxothien‐3‐ylidenemethyl)cyclopropanecarboxylate or RU‐15525 is a new pyrethroid. The action of this compound was tested on Musca domestica and Aedes aegypti and a very strong knockdown effect was observed in comparison with the knockdown effect of allethrin, bioallethrin and (S)‐bioallethrin.
Independent and joint biological activity of isomeric forms of synthetic pyrethroids
Authors: Wickham John C.
Published: November 2006

Various isomeric mixtures of pyrethroids were examined in topical application tests against houseflies, Musca domestica. On the basis of the activities of the separate isomers of 5‐benzyl‐3‐furylmethyl (±)‐cis,trans‐chrysanthemate, it was shown that when combined in pairs to give the (±)‐trans or (±)‐cis or (+)‐cis,trans mixtures the observed mortalities did not differ from those expected by simple additive action calculated by the harmonic mean. In contrast the (±)‐cis,trans mixture showed considerable antagonism with a mortality only 60% of that expected. Similar evaluations using the separate and combined isomers of bioallethrin [(R,S)‐3‐allyl‐2‐methyl‐4‐oxocyclopent‐2‐enyl (allethronyl) ( + )‐trans‐[(1R,3R)‐chrysanthemate] and the corresponding (+)‐cis‐(1R,3S)‐chrysanthemate indicate antagonism calculated to be correlated with the content of the (R)‐isomer of the alcoholic moiety. Hence the activity of the most active isomer of the “allethrin” series, (S)‐3‐allyl‐2‐methyl‐4‐oxocyclopent‐2‐enyl ( + )‐trans‐(1R,3R)‐chrysanthemate, (S)‐bioallethrin, is not fully realised unless it is present in pure form and a substantial part of the value of bioresmethrin (5‐benzyl‐3‐furylmethyl ( + )‐trans‐chrysanthemate] as a killing agent is lost when the racemic form is used. In racemic mixtures there is mutual antagonism between pairs of isomers so that considerable masking of activity occurs.
Herbicides and grassland improvement
Authors: Haggar Roger J.
Published: November 2006

Under normal systems of grassland management, most sown swards become invaded by weed grasses. This ingress is usually associated with a depletion in the size and number of the sown species. Selective herbicides can be used to combat this grass invasion and the results of two experiments are presented to show how low‐dose dalapon in mid‐July can be used for this purpose. When the sown grasses are too severely depleted, some method of introducing seed is required. A new one‐pass technique is now being developed for establishing grass and clover seed into existing swards. After sowing, ways of increasing the clover content are being studied, based on the use of grass‐suppressing herbicides in late winter. In one experiment several‐fold increases in clover growth were recorded 5 months after applying carbetamide (2.8 kg/ha) and propyzamide (0.8 kg/ha).
Residual fumigant effect of 1,2‐dibromoethane (EDB) in fumigations against queensland fruit fly, Dacus tryoni (froggatt), infestations in mangoes
Authors: Swaine Gordon , Corcoran Robert J. , Davey Marguerite A.
Published: November 2006

A residual fumigant effect is demonstrated for fruit held 1 to 3 days within its cardboard carton after fumigation with 1,2‐dibromoethane (EDB). This residual fumigant effect reduces significantly the dosage required for a specified level of control when compared with that required for fruit removed from the carton immediately after airing when fumigation is completed. The effect is due to the slow release of gas sorbed during fumigation and to the slow dispersion of this gas from the carton.
Conversion and leaching of aldicarb in soil columns
Authors: Leistra Minze , Smelt Johan H. , Lexmond Theo M.
Published: November 2006

Aldicarb was applied to soil columns in the laboratory which were leached by artificial rainfall. Concentrations of aldicarb, its sulphoxide and its sulphone in the effluent were measured by gas‐liquid chromatography. The measured results were analysed in some detail using a computation model. Aldicarb and its oxidation products were very mobile in soil, a fact which could be well described after introducing very low sorption coefficients in the computation model. Aldicarb itself was converted at a high rate following first order kinetics (half‐life about 2 days). The best approximations obtained for the rate constant of sulphoxide conversion in two soils were about 0.03 and 0.06/day respectively (half‐lives 23 and 12 days). Only a rather wide range of possible values could be obtained for the rate at which sulphone was decomposed.
Entry of pesticides into the plant symplast as measured by their loss from an ambient solution
Authors: Peterson Carol A. , Edgington Lloyd V.
Published: November 2006

A method was developed to determine the extent of penetration of substances into the plant symplast. The known apoplastic dye trisodium 3‐hydroxy‐5,8,10‐pyrenetri‐sulphonate (PTS) and various systemic pesticides were studied using potato tuber tissue. The dye penetrated only 5% of the volume of living tissue while those pesticides which display an apoplastic pattern of transport in plants penetrated the entire tissue volume. The pesticides diffused freely out of the tissue when it was transferred to fresh medium. It is proposed that the term euapoplastic be used to describe chemicals that behave like the dye, and that the term pseudoapoplastic be used to describe chemicals that behave like atrazine, carbendazim, carboxin and diuron. 2,4‐D, which displays a symplastic transport pattern in the plant, was concentrated by the tissue and did not diffuse out freely. It appears that the property which allows a pesticide to be transported in the symplast is not its ability to penetrate the plasmalemma but rather its ability to be retained by the symplast after entry.
A simple method for the analysis of picloram and 2,4‐D or 2,4,5‐T in mixtures and commercial formulations
Authors: Hargreaves Phillip A. , Rapkins Sonia H.
Published: November 2006

A method is described for the analysis of mixtures of picloram with 2,4‐D or 2,4,5‐T in commercial formulations. The method involves the esterification of the acids in sealed tubes at 105°C using boron trifiuoride‐methanol reagent, followed by extraction, and then estimation by gas chromatography using flame ionisation detection.
Dosage values obtained following pre‐plant fumigation for perennials. 1.1,3‐dichloropropene nematicides in eleven field situations
Authors: McKenry M. V. , Thomason I. J.
Published: November 2006

The movement of 1,3‐dichloropropene nematicides in 11 different field situations was monitored. The eventual dosages of 1,2‐dichloropropane and 1,3‐dichloropropene achieved at various positions in the soil profile are reported. Soil moisture, temperature, texture and profile differences are indicated for each experiment. The influence of soil profile modification, surface sealing techniques and various methods and rates of application are reported.
Phorate residues in aphid colonies on broad bean plants in relation to the site of application
Authors: Galley D. John , Foerster Luis A.
Published: November 2006

Aphis fabae colonies were established on both leaflets of the second leaf of young broad bean plants. Doses of phorate sublethal to the aphids were applied to the roots or to the third leaf. The aphids, their honeydew and the foliage on which they were feeding were analysed and the quantities of toxic and non‐toxic radiolabel determined at intervals. Toxic metabolites were found in the aphids and the leaves but whereas the aphid colonies in all experiments contained approximately similar amounts of the toxic metabolites, the residues in the leaves on which they were feeding differed considerably. The leaves contained more than 100 times as much of these metabolites following the root treatment than after the foliar treatment. These results are discussed in relation to the aphids' feeding site and the probable transport routes of the toxicants.
Excretion and residues of the herbicides benzoylprop‐ethyl flamprop‐isopropyl and flamprop‐methyl in cows, pigs and hens
Authors: Crayford John V. , Harthoorn Paul A. , Hutson David H.
Published: November 2006

Two wild oat herbicides, benzoylprop‐ethyl and flamprop‐methyl were administered to lactating cows at low dose levels (0.3–3.0 mg/kg in total diet) and the excretion of total metabolites in milk, urine and faeces was measured. Total residues in tissues were also determined. Similarly a third and related herbicide flamprop‐isopropyl was fed to cows, pigs and hens (at 0.5 mg/kg in total diet) and the residues were determined in excreta and tissues, including eggs. The amounts of the compounds fed were equivalent to approximately 10–300 times the total residue found in cereal treated in the field. Residues in milk in most cases were well below 0.001 mg/kg; in muscle samples <0.003 mg/kg; and in eggs, 0.0008 mg/kg, decreasing by 50% in approximately 3 days to 0.0001 mg/kg 4 days after the termination of treatment. Elimination of the herbicides from the animals was rapid in every case and this, together with the low residue levels, was attributed to very efficient metabolic de‐esterification to the parent carboxylic acid metabolites (benzoylprop and flamprop). These metabolites possess physical properties ideally suited for excretion via the kidneys and bile into urine and faeces and, conversely, unsuited for transport into milk and eggs.
The metabolism and residues of [14C]Endrin in lactating cows and laying hens
Authors: Baldwin Michael K. , Crayford John V. , Hutson David H. , Street Deborah L.
Published: November 2006

[14C]Endrin was fed to two lactating cows in a portion of their diet for 21 days. The intake was equivalent to approximately 0.1 mg of endrin per kg of total diet. Excretion of radioactivity in milk, urine and faeces reached equilibrium with intake between 4 and 9 days after starting treatment. Milk residues reached 0.003–0.006 mg/kg, were composed of unchanged endrin and were located in the fat. Muscle residues reached 0.001–0.002 mg/kg. Residues in the fat reached a maximum of 0.1 mg/kg and were due to unchanged endrin. [14C]Endrin was administered in corn oil to six laying hens for 21 weeks. The intake was equivalent to approximately 0.13 mg/kg of total diet. Ingestion and excretion were almost in balance at 16–20 weeks. Egg residues reached 0.11–0.18 mg/kg, were composed of unchanged endrin and were located in the yolk. Tissue residues were 0.01 mg/kg in breast, 0.1 mg/kg in leg, 0.17 mg/kg in kidney, 0.47 mg/kg in liver and 1.0 mg/kg in fat. The residues were accounted for as unchanged endrin except in liver and kidney in which part was probably due to polar metabolites in the process of excretion. The results show that endrin is much more rapidly metabolised in cows than in hens. The pathways of metabolism were fundamentally the same in both species, the major product being anti‐12‐hydroxyendrin, which was found un‐conjugated in cow urine and faeces and as the O‐sulphate conjugate in hen excreta. The only observed difference in primary metabolism was some syfl‐12‐hydroxyendrin and 12‐ketoendrin in cows. This pathway was not detected in hens.
A gas‐liquid chromatographic method for determining imazalil residues in citrus fruit
Authors: Greenberg Rachel , Resnick Chaim
Published: November 2006

An electron capture gas‐liquid chromatographic method is described for the analysis of the fungicide imazalil,a 1‐(β‐allyloxy‐2, 4‐dichlorophenethyl)imidazole, in citrus fruit. Recoveries were 80–95% from citrus fruit fortified at 0.50–2.0 mg/kg, with a limit of detection of 0.01 mg/kg.
Degradation and adsorption of carbendazim and 2‐aminobenzimidazole in soil
Authors: Helweg Arne
Published: November 2006

Increasing adsorption of [14C]‐labelled carbendazim in soil took place within a few weeks of incubation and was greatest in soil with a high organic matter content. Carbendazim was slowly decomposed in soil, mainly by soil microorganisms. After 250 days of incubation in two unsterilised soils, 13 and 5% respectively of added [14C]‐carbendazim was recovered compared with 70 and 50% respectively from sterile soils; 4–8% of added carbendazim was recovered as 2‐aminobenzimidazole (2‐AB) from both unsterilised and sterile soil. After 270 days' incubation, 33 and 9% of 14C was recovered as 14CO2 from soil supplied with [14C]‐carbendazim (20 and 100 mg/kg) respectively. Degradation started more rapidly when carbendazim was added to soil preincubated with the fungicide but the degradation rate was very low in all cases, indicating that the compound is a poor microbial energy source and that the degradation is a co‐metabolic process. 2‐AB was found as a degradation product although it appeared to be unstable in soil, decomposing rapidly after a lag period of about 3 weeks; small amounts remained in the soil for several months, however, presumably adsorbed on soil particles.
Problems and limitations in aerosol particle size distribution measurements
Authors: Pengilly Roger W.
Published: November 2006

Various methods for measuring the particle size distribution in aerosols are discussed and their limitations considered.
Formation of nitrite in plants treated with herbicides that inhibit photosynthesis
Authors: Fedtke Carl
Published: November 2006

Avena sativa and Sinapis alba plants were sprayed with selected herbicides and time was allowed for the herbicides to penetrate into the plants. The plants were then illuminated in a nitrogen atmosphere for 60 min. Nitrite (up to 600 nmol/g fresh weight) was found in plants treated with herbicides that inhibit photosynthesis; these plants died a few hours later. Nitrite (up to 408 nmol/g fresh weight) was found in plants treated with herbicides that uncouple oxidative phosphorylation, but here the highest values were obtained after incubation in air. No nitrite was found in control plants incubated in nitrogen or in plants treated with photosynthesis‐inhibiting herbicides and incubated in air. Experiments with plants either grown on different nitrogen sources or adapted to different light intensities rule out the possibility that the damage observed in the plants could be caused by nitrite. Possible reasons for the herbicidally induced damage are discussed.
Determination of individual esters of 2, 4‐D and 2, 4, 5‐T in commercial crops
Authors: Munro Henry E.
Published: November 2006

A rapid gas chromatographic method for the determination of the individual esters of 2, 4‐D and 2, 4, 5‐T in tomato plants and other commercial crops is described. Several suitable esters can be determined at one time. Separation is by steam distillation into a hexane trap followed by clean‐up on a column of “Florisil”. Using a sample of plant material (100 g), 1 μg of each of the esters in the mixture can be determined with recoveries of 72–96% for 2, 4‐D esters and 66–84% for 2, 4, 5‐T esters.
Degradation of the pyrethroid cypermethrin NRDC 149 (±)‐α‐cyano‐3‐phenoxybenzyl (±)‐cis,trans‐3‐(2,2‐dichlorovinyl)‐2,2‐dimethylcyclopropanecarboxylate and the respective cis‐(NRDC 160) and trans‐ (NRDC 159) isomers in soils
Authors: Roberts Terry R. , Standen Mervyn E.
Published: November 2006

The degradation of the pyrethroid insecticide cypermethrin and the geometric isomers NRDC 160 (cis‐) and NRDC 159 (trans‐) in three soils has been studied under laboratory conditions. Samples of the insecticides labelled separately with 14C in the cyclopropyl and benzyl rings were used. The rate of degradation was most rapid on sandy clay and sandy loam soils, 50% of the NRDC 160 and NRDC 159 applied to both soils being decomposed in 4 weeks and 2 weeks respectively. The major degradative route in all soils was hydrolysis of the ester linkage leading to the formation of 3‐phenoxybenzoic acid and 3‐(2,2‐dichlorovinyl)‐2,2‐dimethylcyclopropanecarboxylic acid; soil treated with the cis‐isomer (NRDC 160) was found to contain both cis‐ and trans‐isomer forms of the cyclopropanecarboxylic acid. Further degradation of these carboxylic acids was evident since 14CO2 was released from cyclopropyl‐ and benzyllabelled cypermethrin in amounts equivalent to 24 and 38% of the applied radioactivity over a 22 week period. A minor degradative route was ring‐hydroxylation of the insecticide to give an α‐cyano‐3‐(4‐hydroxyphenoxy)benzyl ester followed by hydrolysis of the ester bond. Under waterlogged conditions the rate of hydrolysis of cypermethrin on sandy loam soil was slower than under aerobic conditions and 3‐phenoxybenzoic acid accumulated in the anaerobic soil.
Design of Trials for Evaluating Insecticides against Some Insect Pests of Vegetables
Authors: Thompson Alwyn R. , Wheatley Geoffrey A.
Published: November 2006

Evaluation trials should provide a maximum of information with minimal effort. Conventional trials designed as randomised block layouts are simple but not very precise and they do not readily permit dose/response relationships to be explored. Semi‐systematic designs, especially in conjunction with log‐dose treatments, can largely overcome these problems. The types of information needed and factors influencing the design of machinery to apply granular insecticides to small plots are discussed. Different experiment designs were tested and standardised designs were developed for evaluating insecticides against cabbage root fly and carrot fly. Examples of results for insecticide efficiency against carrot fly and cabbage root fly and effectiveness in terms of cauliflower yield are given and side‐effects involving phytotoxicity and non‐selectivity are discussed.
The concentrations of aldrin and dieldrin and their photoisomers in the atmosphere
Authors: Baldwin Michael K. , Bennett David , Beynon Kenneth I.
Published: November 2006

Air samples taken in 1973 at a point remote from areas of organochlorine pesticide usage, Bantry Bay in S.W. Ireland, were analysed for aldrin and dieldrin in the vapour state and in association with particupate matter. In addition, some of the samples were analysed for the photoisomers of aldrin and dieldrin, and for pp'‐DDT, 1,1‐dichloro‐2,2‐di‐(4‐chlorophenyl) ethylene (pp'‐DDE) and pp'‐IDE. Detection and quantitation of all compounds were by gas‐liquid chromatography with electron capture detection (g.l.c./e.c.). Confirmatory evidence for the presence of dieldrin and pp'‐DDE was obtained with some samplesusing gas‐liquid chromatography with mass fragmento‐graphic detection (g.l.c./m.f.). Dieldrin was detected in all seventeen samples of air taken, but the mean concentration was 0.36 ng/kg and the range of concentrations was 0.06–1.60 ng/kg. Aldrin was not detected in the samples examined, neither were the two photoisomers. Only pp'‐DDE of the pp'‐DDT group of compounds was detected in the nine samples examined, and the apparent mean concentration was 0.14 ng/kg. None of the compounds was detected in particulate matter.
The insecticidal and acaricidal properties of some 3‐alkylcarbamoyloximino‐2, 4‐dimethyl‐1,5‐benzodiazepines
Authors: Clifford David P. , Jeffrey Peter
Published: November 2006

A number of the title compounds were synthesised, evaluated and shown to have activity against Aphis fabae.
Resistance to synthetic pyrethroids in a DDT‐resistant strain of Boophilus microplus
Authors: Nolan James , Roulston William J. , Harry Wharton R.
Published: November 2006

The susceptibility of a standard reference strain of the cattle tick Boophilus microplus, to a group of synthetic pyrethroids, has been compared with that of a DDT‐resistant strain. Cross resistance has been demonstrated in laboratory and field tests.
Residues of zineb and ethylene thiourea in orchard treated pears and commercial pear products
Authors: Ripley Brian D. , Simpson Charles M.
Published: November 2006

Zineb and ethylene thiourea (ETU) residues were monitored in Bartlett pears after spraying with zineb (5.04 kg a.i./ha). Zineb dissipated seven times faster in the first 10 days after application than in the subsequent days of the study; ETU residues ranged from 0.02 to 0.01 mg/kg over the 21 day trial. A 3–6% conversion of ethylene‐bisdithiocarbamate to ETU was found upon boiling treated pears. Analysis of randomly selected commercially canned pears and baby food pear purée showed no zineb residues but LT0.05 mg ETU/kg was present in four of the six samples of baby food.
Tracing insecticide spray droplets by sizes on natural surfaces. The state of the art and its value
Authors: Uk Solang
Published: November 2006

Recent trends in integrated chemical and biological pest control call for further refinement of the effectiveness of existing chemical pesticides by more efficient spray application. One aspect of improving spray efficiency is by the use of the correct range of droplet sizes. In this way the volume of spray, and the amount of active ingredient used, particularly in ultra‐low volume techniques, can be further optimised, and when combined with correct application time, gives maximum biological efficiency with minimum disturbance of the environment. This necessitates a study of the size spectrum of droplets deposited on rigorously defined biological targets which in turn calls for an investigation of suitable tracer methodology. Additional details of the previously published fluorescent particle method are discussed, and its reappraisal shows that it is a unique method capable of estimating droplet sizes on all biological surfaces, especially insect larvae. The reversibly soluble fluorescent pigment method based on the relative balance between soluble and insoluble state of the pigment proves highly successful in imprinting fluorescent droplets on broad leaves, particularly on cotton.
Pharmaceutical implications of particle growth at high relative humidities
Authors: Byron Peter R. , Davis Stanley S. , Bubb Malcolm D. , Cooper Paul
Published: November 2006

Official standards governing the particle size distributions of inhalation aerosols make no allowance for the high relative humidity within the respiratory tract. Our studies suggest that distributions determined under ambient conditions provide little real information about the fate of particles within the lungs.
Experimental chemotherapy and chemoprophylaxis of filariasis
Authors: Lämmler Georg
Published: November 2006

This paper describes some of the current methods used for the development of new chemotherapeutic agents against filarial parasites. These are based on the extensive previous experience of experimental chemotherapy of filariasis and of the development of new rodent and non‐rodent filarial models. A review on the chemotherapeutic activity and micro‐ or macro‐filaricidal potency of some well‐known or recently developed filaricidal drugs is given, based on results obtained with Litomosoides carinii infection of Mastomys natalensis. Corresponding information on the chemo‐prophylactic activity of filaricides is presented and discussed, with regard to the relevancy and need for the further development and evaluation of anthelmintics in filarial infections.
The effect on earthworm populations of methods of spraying benomyl in an apple orchard
Authors: Stringer Austin , Lyons Clive H.
Published: November 2006

Compared with high volume (2240 litre/ha) sprays, low (560 litre/ha) and ultra‐low volume (45 litre/ha) sprays of benomyl were less toxic to earthworms. The decrease in populations was proportional to the quantity of fungicide deposited on the ground; regression lines, probit (% reduction) on log (fall out in g/ha), are given for populations of Lumbricus terrestris and all species together. The reduction in numbers was similar for all species except L. terrestris and Allolobophora longa, L. terrestris was more susceptible to the deposits than the other species; A. longa was less affected, probably because it was in summer diapause.
An introduction to the principles of neurophysiology
Authors: Dowson Richard J.
Published: November 2006

Several of the research papers in this Symposium will refer to physiological processes with which most non‐biologist readers are unfamiliar. The aim of this introductory paper, therefore, is to give those people a broad introduction to the basic principles of nerve and muscle physiology.
The actions of pyrethroids upon the peripheral nervous system and associated organs in the locust
Authors: Clements Alan N. , May Theresa E.
Published: November 2006

The actions of a number of pyrethroids upon the crural nerve, chordotonal organs and skeletal muscles of the desert locust were investigated. The compounds were principally 3‐phenoxybenzyl esters (with or without an α substituent), and particular attention was given to fenvalerate and related compounds. Four different effects were observed, both during the early stages of intoxication of intact locusts and during perfusion of physiological preparations with low concentrations of the pyrethroids. The type of effect produced was determined by the molecular structure of the pyrethroid. Knockdown activity was associated with one particular effect, and it is suggested that it is the type of action caused by a pyrethroid, rather than its rate of penetration into the insect, that determines whether or not it will have knockdown activity.
Skin damage of meyer lemon by fumigation with 1,2‐dibromoethane (EDB)
Authors: Swaine Gordon , Corcoran Robert J. , Cranny Anne E. , Davey Marguerite A.
Published: November 2006

Meyer lemons are susceptible to skin damage by EDB vapour. The damage can be caused by excessive vapour concentration during fumigation. Residual fumigant desorbed from fibreboard cartons containing the fruit is also of major importance in relation to damage where post‐fumigation ventilation is restricted. The damage was minimised by a period of 4 h ventilation in the chamber after fumigation using the standard treatment of 18 g EDB/m3 for 2 h at 21°C.
The nature of bound residues derived from triforine in barley plants
Authors: Rouchaud Jean , Decallonne Jacques R. , Meyer Joseph A.
Published: November 2006

The shoots of barley plants root‐treated with [3H]‐triforine fungicide (uniformly labelled in the piperazine ring) were analysed 30 days after treatment. Methanol extraction left a solid plant residue which contained 33% of the total 3H which had been incorporated into the shoots. Methanol acidified with hydrochloric acid extracted a further 18% of the triforine‐derived bound residues as N‐[2,2,2‐trichloro‐1‐(piperazin‐1‐yl)ethyl]formamide (8%), and piperazine (10%). In the plants, these compounds had thus been complexed to plant constituents. Hot dimethyl sulphoxide (DMSO) extracted a further 13% of the total 3H, leaving a solid residue (mainly cellulose) which contained 2% of 3H, perhaps incorporated into the cellulose. Evaporation of the solvent from the DMSO extract gave a solid, the radioactivity of which (13%) could not be extracted by methanol. A part (7%) of this radioactivity could be released by successive hydrolysis with amyloglucosidase and β‐glucosidase, which generated a complex mixture of polar and water soluble unknown radioactive compounds not including piperazine. These latter compounds would be the products of extensive metabolism of triforine (and its metabolite piperazine) bound to, or incorporated into starch. Most (11%) of the radioactivity of this solid could be released by hydrochloric acid hydrolysis, which also generated a complex mixture of polar and water soluble unknown radioactive compounds not including piperazine; a part (4%) of them could have been associated with lignin in the plant.
Effects of DDT on the cockroach nervous system at three temperatures
Authors: Gammon Derek W.
Published: November 2006

Some effects of DDT on the cockroach nervous system have been correlated with poisoning symptoms, using free‐walking cockroaches with implanted electrodes. Experiments at 16.5°C and 32°C used LD95 doses and at 25°C, an estimated LD95. DDT had excitant actions on each nerve studied; cercal afferent and efferent neurones, and abdominal interneurones. The effects on the central nervous system became more marked as temperature was reduced, despite the smaller quantity of DDT employed, but the excitant actions on the peripheral nervous system were not quantified. It is suggested that the effects of DDT on the cockroach nervous system could account for the negative temperature coefficient of toxicity of DDT.