Showing papers by "Agriculture and Agri-Food Canada published in 1975"
TL;DR: The isolation of a myotropic substance, proctolin, associated with the innervation of the viscera of the cockroach, Periplaneta americana, is reported and was homogeneous on paper and thin-layer chromatography and on high-voltage paper electrophoresis at pH 3·5 and 6·4.
251 citations
TL;DR: The persistence of a small amount of a 1,2-dihydroxybenzene-3,5-disulfonate (Tiron) oxidizing species in the dark supports the concept of Tiron accessibility but not the superoxide dismutase accessibility of superoxide anion bound in its formative enzyme complex.
66 citations
TL;DR: Carbon dioxide was found to potentiate the action of phosphine against a normal strain of Tribolium confusum and normal and resistant strains of Sitophilus granarius so that the length of the exposure period could be reduced.
51 citations
TL;DR: Synthetic (E)-9-oxo-2-decenoic acid (9-ODA) was as attractive to drones as ether extracts of queen heads, suggesting that 9- ODA is the component of the sex pheromone that attracts drones from a distance.
Abstract: Synthetic (E)-9-oxo-2-decenoic acid (9-ODA) was as attractive to drones as ether extracts of queen heads, suggesting that 9-ODA is the component of the sex pheromone that attracts drones from a distance. However, other substances produced in the heads of both virgin and mated queens cause drones to hover near a lure. Positive anemotaxis and short-range visual stimuli are also involved in the mate-finding process. “Keeper” substances ensure the gradual release of the pheromone. (E)-9-Hydroxy-2-decenoic acid (9-HDA) did not attract drones from a distance or affect their behavior near a lure.
36 citations
TL;DR: In this paper, two buried paleocatenas were studied to determine some features and techniques by which buried soils could be recognized, and to define their pedological characteristics, their lateral variation, and their contemporary environment.
29 citations
TL;DR: The hyphae wall of Fusarium sulphureum Schlect was isolated and purified and the major cell wall component N-acetylglucosamine was shown by X-ray diffraction analysis to be present as chitin.
25 citations
TL;DR: A technique for mass rearing the carrot weevil, Listronotus oregonensis (LeConte), was described in this article, where adults were provided with carrot roots for food and oviposition sites.
Abstract: A technique for mass rearing the carrot weevil, Listronotus oregonensis (LeConte), is described. Adults were provided with carrot roots for food and oviposition sites. Larvae developed directly in these roots. Different temperature regimens for larval rearing were tested and best results were obtained using 21 °C for the first 2 weeks of larval development and 27 °C thereafter. Photoperiod was maintained at 16 h and relative humidity at 70%. Under these conditions, 97.6% of adults emerged in 39–42 days.
24 citations
TL;DR: It is thought it worthwhile to apply the same physico-chemical techniques in an attempt to isolate virus from mouse brains infected with scrapie agent as repeated fluorocarbon extractions of mink tissues infected with Aleutian disease virus have resulted in isolation of the virus.
Abstract: SCRAPIE, a naturally occurring slow virus disease of sheep and goats, has been transmitted experimentally to the mouse, rat, gerbil, mink, hamster, vole and monkey1. The agent has shown an unusual resistance to ultraviolet irradiation2, nucleases3 and β-propiolactone4. The precise nature of the scrapie agent, however, has yet to be defined. It is not known whether it is a virus, some type of self-replicating cell membrane, or part of a membrane5. The viroid hypothesis of the scrapie agent of Diener6 has been discounted7,8. Several different particles have been seen in thin sections of naturally and experimentally infected scrapie tissues9–11. As repeated fluorocarbon extractions of mink tissues infected with Aleutian disease virus (ADV), which causes persistent infection of mink, have resulted in isolation of the virus12,13, we thought it worthwhile to apply the same physico-chemical techniques in an attempt to isolate virus from mouse brains infected with scrapie agent.
22 citations
TL;DR: Recoveries of paraquat added to lettuce, carrots and onion at 0.5, 0.1, and 0.05 ppm were between 75 to 86%, with maximum standard error of 4%.
Abstract: A method is described for determining paraquat residues in lettuce, carrots and onions. The procedure is based on the extraction of the sample with 5N H2SO4 and catalytic hydrogenation of the acid extract. This is followed by column cleanup on alumina and subsequent determination by gas chromatography. Recoveries of paraquat added to lettuce, carrots and onion at 0.5, 0.1, and 0.05 ppm were between 75 to 86%, with maximum standard error of 4%. The lower limit of this method is in the 0.05 ppm range.
20 citations
TL;DR: It is shown that the so-called "non complement-fixing" viral antibodies in the serum of these animal species can be demonstrated by the MDCF test, as well as the micro AGP test, which is possible to differentiate antigenically BT virus from EHD virus.
Abstract: The viral antibodies in the serum of cattle, sheep and deer are not detectable in the ordinary direct CF test. We have shown that the so-called "non complement-fixing" viral antibodies in the serum of these animal species can be demonstrated by the MDCF test. The MDCF test, as well as the micro AGP test, are group reactive, with all BT isolates studied. However, it is possible with these tests to differentiate antigenically BT virus from EHD virus. The FAT was also useful in differentiating BT virus grown in TC cells from the EHD virus. In the PRN test, all the BT virus isolates studied cross reacted and although quantitative differences were frequently observed, no obvious antigenic classification was possible with the antiserums used in this work. Reactions between the BT viral isolates and the EHD virus were all within the limits of what is presently considered to be non-specific inhibition.
17 citations
TL;DR: Analytical methods include polarography by DME and RPE, titrimetry, spectrophotometry, and GC with microthermal conductivity, hydrogen flame ionization, electron capture, microcoulometric, thermionic, and flame photometric detector systems, with backup by enzymatic, radiometric, NAA and X-ray flourescence methods.
Abstract: The terms fumigant and fumigant residue are defined. Interrelationships between physically and chemically bound residues, storage environments, nature of the substrate and other influencing factors are outlined. Analytical methods include polarography by DME and RPE, titrimetry, spectrophotometry, and GC with microthermal conductivity, hydrogen flame ionization, electron capture, microcoulometric, thermionic, and flame photometric detector systems, with backup by enzymatic, radiometric, NAA and X-ray flourescence methods. Various aspects are illustrated with different fumigants used commercially. Supplementary methods to extend the power and usefulness of analytical methods in fumigant research are indicated.
TL;DR: Fenitrothion O,0-dimethyl-0-(4-nitro-m-tolyl) phosphorothioate is extensively used in Canadian forests for the control of spruce budworm and its presence in technical products is not unexpected.
Abstract: Fenitrothion O,0-dimethyl-0-(4-nitro-m-tolyl) phosphorothioate is extensively used in Canadian forests for the control of spruce budworm. After aerial spraying, the analysis of washings from a glass plate, used to sample at ground level, revealed traces of a second organphosphorus compound. A mass spectrum of this material showed a base ion at m/e 125, a parent ion of m/e 277 and an ion at m/e 260 (m-17), which suggested that the compound was an isomer of fenitrothion. This was confirmed by comparison with an authentic sample of S-methyl fenitrothion. JOINER and BAETCKE (1973) attributed the finding of S-ethyl and S-nitrophenyl isomers of parathion on cotton leaves one week after treatment to the effect of light. Since the sample of fenitrothion was exposed to light for only a short period of time (1-2 hrs) after spraying, the S-isomer was thought not to arise from photolysis. The S-alkyl isomers can be formed by thermal isomerisation as was first shown by EMMETT and JONES (1911) and later by JAGLAN et. al. (1970b), by photolysis (COOK and PUGH 1957, and EL-RAFFAI and HOPKINS 1966), and by alkylation (BURN and CADOGAN 1961). Their presence in technical products is therefore not unexpected. The amount present will depend on the method of preparation of the sample and on the storage conditions. METCALF and MARCH (1953) have reported that the amount of S-ethyl isomer varied from 5-20% in some parathion samples.
TL;DR: It is determined that the plant in question is in fact a male of Datisca cannabina L. are remarkable mimics of Cannabis sativa L. (females are less so).
Abstract: In a recent paper in Economic Botany, Quimby et al. (1973) described a peculiar variant of Cannabis, found on a herbarium sheet housed in the Field Museum of Natural History, Chicago, Illinois (accession number 1628511). This specimen was identified on the herbarium label as Cannabis indica Lam., and Quimby et al. interpreted it as an unusual example of Cannabis sativa L., with pinnate leaves. Two photographs of this specimen were included in the paper '(figs. 23, 24, p. 127; not fig. 22 as stated in text). The specimen has been cited several times in recent symposia, and I have received a number of inquiries concerning its nature. Dr. John McNeill of this institute and I have determined that the plant in question is in fact a male of Datisca cannabina L. Male plants of Datisca cannabina L. are remarkable mimics of Cannabis sativa L. (females are less so). As noted by Steam (1974): "In the Hortus Cliffortianus, Linnaeus provided a short diagnosis, Cannabis foliis digitatis, to distinguish the true hemp from a then imperfectly known plant diagnosed there as Cannabis foliis pinnatis, but named Datisca cannabina in the first edition of the Species Plantarum." On close examination, a wealth of characters distinguish the two species. Indeed, they are so distant that Cronquist (1968) assigns
TL;DR: Charolais-sired steers on both regimes had the fastest gain and were the first to reach slaughter weight and Limousin-sire steers raised on the fast-gaining regime had the highest dressing-out percentage, and the largest area of m.
Abstract: A total of 178 castrated male cattle (steers), the progeny of Charolais, Hereford and Limousin bulls mated to Holstein-Friesian and Ayrshire cows, were raised from 8 months of age to 545 kg (slaughter weight) on fast- or slow-gaining regimes. The steers on the fast gaining regime were fed a grain mixture with little hay, while those on the slow-gaining regime grazed all summer and were wintered on hay supplemented with a little grain.The steers on the fast-gaining regime were more efficient in feed conversion ratio, had 0·42 kg per day higher live-weight gain, reached slaughter weight 306 days earlier, and had 2% higher dressing-out percentage, 5·7 mm thicker fat and 5 mm2 larger area of m.longissimus thoracis than those on the slow-gaining regime.Charolais-sired steers on both regimes had the fastest gain and were the first to reach slaughter weight. Limousin-sired steers raised on the fast-gaining regime had the highest dressing-out percentage, and the largest area of m. longissimus thoracis on both regimes. Hereford-sired steers had the thickest fat cover and the smallest area of m. longissimus thoracis. Little difference was found between the steers from Holstein and Ayrshire cows.
01 Jan 1975
TL;DR: Red raspberry (Rubus idaeus) is an important crop in southwestern British Columbia and ranks second in the world in terms of yield per acre, but in recent years plantings declined considerably, with yields in many fields down by 40–50% and plantings becoming unproductive after only 7–8 yr.
Abstract: Red raspberry (Rubus idaeus) is an important crop in southwestern British Columbia and ranks second in the world in terms of yield per acre. Plantings free of disease remain productive for 10–15 yr and yield 4–5 ton/acre. However, in recent years plantings declined considerably, with yields in many fields down by 40–50% and plantings becoming unproductive after only 7–8 yr. No single factor appears responsible for this decline and in fact it may be a complex of biotic and abiotic factors. It is estimated that in 1973 there was a 31% loss to the potential 9 million dollar industry due to this slow decline problem.
TL;DR: The effectiveness of codling moth control by the sterile-insect release method depends on the frequency of effective matings between the released sterile males and the wild females; the higher the frequency, the more sterility is introduced into the wild population.
Abstract: The effectiveness of codling moth, Laspeyresia ponmnella (L.), control by the sterile-insect release method depends on the frequency of effective matings between the released sterile males and the wild females (Proverbs 1971). The higher the frequency of this mating, relative to the matings between the wild males and wild females, the more sterility is introduced into the wild population; this applies irrespective of whether only sterile males or sterile males and females are used for release.
TL;DR: The method was used for the simultaneous analysis of 2,4-D, dicamba, and mecoprop residues in wheat, barley, and soil samples obtained from fields sprayed with the herbicide formulation Kil-Mor.
Abstract: A method has been developed for the simultaneous analysis of 2,4-D (2,4-dichlorophenoxy-acetic acid), dicamba (2-methoxy-3,6-dichloro-benzoic acid), and mecoprop (MCPP; 2-[(4-chloro-o-tolyl) oxy] propionic acid) residues in soil, wheat, and barley. Soil and crop samples are extracted with acidic acetone and methanol, respectively. The extracts in diethyl ether are esterified with diazomethane and cleaned up by passing through a Florisil column. Extracts are analyzed by gas-liquid chromatography, using an electron capture detector to determine 2,4-D and dicamba residues. Mecoprop in the extract is not detected at low levels of concentration. However, bromination of the extract increases the response of the electron capture detector to mecoprop. The method is sensitive to about 0.05 ppm 2,4-D and dicamba and 0.5 ppm mecoprop. Recoveries of these 3 herbicides added to soil, wheat, and barley samples at 0.05, 0.1, 0.5, and 1.0 ppm levels were between 65 and 93%. The method was used for the simultaneous analysis of 2,4-D, dicamba, and mecoprop residues in wheat, barley, and soil samples obtained from fields sprayed with the herbicide formulation Kil-Mor.
TL;DR: Eggs and early stage larvae were most susceptible to methomyl, chlorpyrifos, and chlorphoxim, while later stage larvae, pupae, and adults became increasingly tolerant to these insecticides, and none of the treatments was phytotoxic.
Abstract: In primary laboratory screening tests, the effectiveness of 30 insecticides applied by direct contact to 3rd stage larvae was assessed relative to carbaryl for control of Pseudaletia unipuncta (Haworth). Many of the insecticides were more effective than carbaryl. Methomyl, chlorpyrifos, chlorphoxim, and parathion were the most toxic ovicides tested. Eggs and early stage larvae were most susceptible to methomyl, chlorpyrifos, and chlorphoxim, while later stage larvae, pupae, and adults became increasingly tolerant. Five promising insecticides were field-tested using micro plots planted with sweet corn and infested with laboratory-reared larvae, with carbaryl being included for comparison. Carbofuran G applied as a band application at 3.36 kg/ha did not provide adequate control. Methomyl, chlorpyrifos, leptophos, carbofuran, and WL 24073 ( O -(2-chloro-2,5-dichlorophenyl) vinyl) O -methyl ethylphosphonothioate) applied as broadcast sprays at 0.28 to 0.56 kg/ha were as or more effective than carbaryl at 2.24 kg/ha. None of the treatments was phytotoxic. No residues of chlorpyrifos, chlorpyrifos-oxon, leptophos, leptophos-oxon, or carbaryl were detected on the corn at harvest.
TL;DR: The requirement to confirm the identity of pesticide residues in the nanogram or picogram range is becoming increasingly important in environmental studies and chemical derivative formation followed by electron capture gas chromatography has found wide acceptance.
Abstract: The requirement to confirm the identity of pesticide residues in the nanogram or picogram range is becoming increasingly important in environmental studies (McCULLY 1969). Various methods have been employed including thin layer chromatography (KOVACS 1963, MINYARD and JACKSON 1965); extraction p-values (BOWMAN and BEROZA 1965); gas chromatography mass spectrometry combination (DAMICO et al. 1970) and multiple gas-liquid chromatography column methods (FAHEY and SCHECTER 1961). Chemical derivative formation followed by electron capture gas chromatography has been employed in a number of laboratories performing routine analyses and has found wide acceptance (McCULLY 1969, WOODHAM et al. 1972; COCHRANE and CHAU 1970). The latter has the advantage of being convenient and sensitive. The identification of organophosphorus insecticides can be made more specific by the use of a flame photometric or an alkali flame ionisation detector rather than an electron capture detector. Even so, the response of these detectors is not unequivocal evidence for the presence of a specific insecticide (ASKEW et al. 1969, GIUFFRIDA 1964, BRODY and CHANEY 1966).
TL;DR: A comparison has been made of the disease produced in white-tailed deer by the viruses of epizootic haemorrhagic disease and bluetongue and some of the viral properties has been described.
Abstract: A comparison has been made of the disease produced in white-tailed deer by the viruses of epizootic haemorrhagic disease and bluetongue. The similar nature of these diseases in deer and of some of the viral properties has been described. Although these two viruses are considered to be distinct, it is possible by employing an unnatural procedure to produce antibody which will demonstrate a minor antigenic component common to both viruses. Biological features that differ between the two viruses have also been noted.
TL;DR: In this paper, a model which includes concentration, time and interaction between the two was found to describe the dosage-response relationship better than concentration and time alone, and the inclusion of data on uptake into the model did not provide appreciable contribution to explain the observed mortalities beyond that already given by concentration.
01 Jan 1975
TL;DR: In recent years, the economic importance of herbicides has greatly exceeded that of other pesticides and their use for weed control has had a tremendous impact on crop production as well as on management of non-agricultural land.
Abstract: In recent years the economic importance of herbicides has greatly exceeded that of other pesticides. Their use for weed control has had a tremendous impact on crop production as well as on management of non-agricultural land. They are being used in increased quantity and new compounds are being added to the list of herbicides every year. Thus, there exists an increasing demand for analytical methodology of herbicide residues.
01 Jan 1975
TL;DR: To date, two nematode transmitted viruses and their vectors have been found in British Columbia and they have limited distribution and they are currently of only minor economic importance.
Abstract: To date, two nematode transmitted viruses and their vectors have been found in British Columbia Both are Nepo viruses and both are transmitted by Xiphinema americanum However, the two viruses have limited distribution and they are currently of only minor economic importance
TL;DR: The nodes formed by the mid-ventral tracheal anastomoses in abdominal segments 3–6 are modified into conspicuous glandular organs in larvae of certain Lepidoptera.
Abstract: The nodes formed by the mid-ventral tracheal anastomoses in abdominal segments 3-6 are modified into conspicuous glandular organs in larvae of certain Lepidoptera. They comprise clusters of extremely large cells penetrated by an extensive lacunar system opening onto the tracheal wall. These cells appear to sequester substances from the haemolymph which may be conjugated with a lipoid synthesized within them and the product excreted into the lacunar system, ultimately passing into the tracheal lumen.
TL;DR: In this article, a tracer was used as a gaseous tracer to determine the rate of unassisted air movement in the microclimate of grain stored in steel bins.
Abstract: Sulphur hexafluoride, SF6, was used as a gaseous tracer to determine the rate of unassisted air movement in the microclimate of grain stored in steel bins. The airspeeds were influenced by the nature of the stored products, the size and geometrical shape of the kernels and the storage temperature. Air movement rates varied from 3 to 108 in/h depending on the temperature gradients. This is the first quantitative evidence of the ultraslow speed of air movement in stored grain.
TL;DR: Studies on existing monotelotrisomics have shown that those representing the long arm frequently resemble the corresponding primary trisomic in gross morphology while short arm counterparts are rarely distinguishable from diploids.
Abstract: Recent developments in the study of aneuploids in barley are reviewed. To date five complete series of primary trisomics have been produced. Considerable progress has been made toward the production of a complete set of monotelotrisomics. Eleven of the possible 14 have thus far been identified though not all in the same genetic background. Studies on existing monotelotrisomics have shown that those representing the long arm frequently resemble the corresponding primary trisomic in gross morphology while short arm counterparts are rarely distinguishable from diploids. The average transmission rate of extra telos through female gametes was 31.9% with all showing a low rate of male transmission. In 81.3% of cells at metaphase 1 of meiosis the extra telos are synapsed with normal homologues to form heteromorphic trivalents. Tandem-chain configurations were the predominant type.