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1.
Summary Supercooling point elevation to –3.2±1.3°C among 17 freeze tolerantChymomyza amoena larvae was delayed until January, 1983 in the mild winter of 1982–83 and occurred despite particulate matter in the gut. The larval population in mid-Michigan is polymorphic for both freeze tolerant and freeze sensitive larvae. One substrate,Malus coronaria fruits, appears to be a neutral niche supporting both phenotypes in the population.Discussions with K. E. Zachariassen and J. Duman before beginning the work onC. amoena cold-hardiness were invaluable. Visits of both at Michigan State University were jointly sponsored by the Depts. of Zoology and Entomology. H. Carson suggested thatC. ameona might be breeding in endemic crabapples. G. Parmalee at MSU showed one of us (HTB) a long established thicket ofMalus coronaria. The MSU Climatology Center supplied all Lansing area weather data.  相似文献   

2.
Summary Proline is accumulated by overwinteringC. amonea larvae. Mortality averages over 50% by spring. PGMF in the population shifts from 70% in summer to less than 50% during winter, increasing again in summer. Product synthesis from stored glycogen may be mandated in dipteran larvae also using larval proteins for cold hardiness when completion of development is delayed until spring.Thanks are gratefully extended to Derek Lamport and Patrick Muldoon of the MSU/DOE Plant Biology Laboratory for the amino acid analyses. Thanks are also extended to Jerry Wolfe, Director of Mt. Lake Biological Station in summer, 1985 and Blaine Cole, Director beginning summer, 1986 for research space, to the University of Virginia, Charlottesville for a fellowship for the work at MLBS in summer, 1986 and to all the property owners in Michigan and Virginia who allowed collection at their orchards, farms, gardens or residences. Apples in January and March, 1986 were from a university research orchard. — This paper is dedicated to Hampton L. Carson on his retirement.  相似文献   

3.
Summary Chymomyza amoena larvae in apples in summer were found to be either potentially freeze tolerant or to supercool. By late September only potentially freeze tolerant larvae were recovered from apples. Larvae from walnut husks in winter supercooled to avoid freezing. However, freeze tolerance could be induced in laboratory grown larvae by placing them in apples around the seed area and maintaining them at chilling temperatures for several weeks. Overwintering mechanisms employed byC. amoena larvae in Michigan appear to depend upon larval feeding site.Prof. Davis at Michigan Agricultural College placed 9C. amoena emerging from apples in August and Sept. 1891 along with codling moth in the MAC (=MSU) Entomological Museum collection.  相似文献   

4.
Summary Chymomyza amoena, a member of the family Drosophilidae, is now breeding in fallen apples in the state of Michigan.C. amoena larvae can overwinter in fallen apples, completing development and emerging as adults in the summer. Cold resistance during the overwintering phase may not depend upon the accumulation of glycerol or other sugar alcohols.  相似文献   

5.
Summary Hagenius brevistylus lost mass by evaporation in a moderately desiccating environment at the rate of 20.4 mg h–1, and died of desiccation in less than 1 day at a body mass of 79.8% of their normally hydrated mass. It was estimated thatHagenius minimally would have to consume the equivalent of 60% of its body mass each day to meet its daily water requirements. This amount of food is equivalent to that necessary to power flight of a dragonfly for 4.6h.This research was financed in part by a grant from the American Philosophical Society to C.R.T., and was conducted at the University of Michigan Biological Station, Douglas Lake (USA).  相似文献   

6.
Summary North American populations of the monarch butterfly,Danaus plexippus, have been found to contain pyrrolizidine alkaloids and their N-oxides. Analytical methods (TLC, GC, and GC/MS) have been developed to isolate, quantitate, and structurally elucidate the alkaloids. Examples of at least two classes of pyrrolizidine alkaloids have been identified, the macrocyclic diesters, senecionine, integerrimine, and seneciphylline, and the monoesters, echinatine, intermedine, and lycopsamine.21 November 1986This work was supported by NSF (Grants BSR-81-19391 and BSR-81-19382), and a Stauffer Chemical Company fellowship. We thank David Hodapp, Mark Stelljes, and Cordula Bruenner for technical help, Dr T.P. Krick, University of Minnesota, St. Paul, Minn., USA, for assistance in GC/MS analysis of PAs, and Dr J.A. Edgar, CSIRO, Parkville, Victoria, Australia, for samples of authentic reference compounds.  相似文献   

7.
It has been suggested that a common sex pheromone composition may account for interspecific sexual interactions observed with certain moths in the Arctiidae. In this study, it is demonstrated that the sex pheromones released by females of the Scarlet Tiger Moth,Callimorpha dominula L., and the Cinnabar Moth,Tyria jacobaeae L., have similar activities and elute at the same retention time on analysis by coupled gas chromatography (GC)-electrophysiology with males from each species. Peak enhancement on GC, chiral GC and coupled GC-mass spectrometry using authentic compounds show that the sex pheromone for bothC. dominula andT. jacobaeae is (3Z,6Z,9S,10R)-9,10-epoxyheneicosa-3,6-diene.  相似文献   

8.
Summary The fresh water mollusc,Lymnaea tomentosa, the intermediate host of the liver fluke is heavily infested under natural conditions with ectocommensal annelid,Chaetogaster limnaei. These annelids which destroy the larval stages ofFasciola hepatica have been observed in the laboratory. The association ofC. limnaei with the snail intermediate host is of value in exploiting a control measure against economically important liver fluke disease.I am greatly indebted to Dr. M. J. Howell for his critical comments and help in preparing this research note. Also to the Australian National University authority for awarding a scholarship to carryout this work.  相似文献   

9.
Summary Giant mitochondria were observed in the perikarya and dendrites of Purkinje cells in the developing cerebellar cortex of the lizardGallotia galloti at sevral stages previous to hatching. Such mitochondria are absent from the adult cerebellum.4 December 1986The authors would like to thank Prof. L. Puelles (Murcia University) for his critical assistance and the Edafology Department of La Laguna University for facilities offered, specially for the use of the electron microscope. This work has been pertially suported by a CAICYT research grant No. 909-2.  相似文献   

10.
Summary Males and females of Chilean strains ofDrosophila subobscura exhibit a pronounced tendency toward homogamic mating. This tendency shows a clear relation to the distance between the geographic localities from which the respective strains came. Nevertheless, when the Chilean flies are confronted with European strains, the ethological isolation is observed in some cases but not in others, depending on the geographic origin of the strains.Acknowledgments. This work has been partially supported by grants from the Univ. of Chile (Project B 729-8345) and PNUD/UNESCO (RLA 78/024). We are most grateful to Prof. D. Sperlich of the University of Tübingen who provided theD. subobscura strains from Tübingen and Sicily, and Prof. A. Prevosti from the University of Barcelona and R. de Frutos from the University of Valencia who provided the strains of Mallorca and Almería. We are finally obliged to Mr E. Zárate for his technical assistance.  相似文献   

11.
Summary The brain allatotropic hormone (ATTH) is released inGalleria mellonella from the Median neurosecretory cells located in the pars intercerebralis. These cells show the ability to elicit supernumerary larval molts upon implantation into sensitive host larvae, and the ability to in vitro stimulate the juvenile hormone synthesis in corpora cardiaca-corpora allata glands ofG. mellonella.11 November 1986Acknowledgments. I am greatly indebted to Wesleyan University (Connecticut, USA) for supporting this study.  相似文献   

12.
Summary Although at least 159 cases of interspecific hybridization between closely related species ofDrosophila have been obtained under laboratory conditions, only 7 cases of natural interspecific hybridization have been recorded. We report yet another case, concerningD. malerkotliana andD. bipectinata.Thanks are due to the University Grants Commission for supporting the research project of J.P.G. and to the Head of the Department for laboratory facilities.  相似文献   

13.
Summary Luffolide (4) is a minor metabolite of the spongeLuffariella sp. from Palau. The structure of luffolide was determined by single crystal X-ray analysis. Luffolide is relatively unstable and undergoes a complex cyclization reaction to give the hexacyclic products5 and6. Luffolide (4) has some of the anti-inflammatory properties of manoalide (1): this may help to define the chemical reaction between manoalide (1) and phospholipase A2.All crystallographic calculations were done on a PRIME 9950 computer operated by the Cornell Chemistry Computing Facility. Principal programs employed were: FOBS, a data reduction program by G.D. Van Duyne, Cornell University, 1987; MULTAN 80, and RANTAN 80, systems of computer programs for the automatic solution of crystal structures from X-ray diffraction data (locally modified to perform all Fourier calculations including Patterson syntheses) written by P. Main, S. E. Hull, L. Lessinger, G. Germain, J. P. Declercq and M. M. Woolfson, University of York, England, 1980 BDLS, an, anisotropic block diagonal least squares refinement written by K. Hirotsu, E. Arnold, and G. D. Van Duyne, Cornell University, 1987; PLUTO 78, a locally modified crystallographic illustration program by W. D. S. Motherwell, Cambridge Crystallographic Data Centre, 1978; and BOND, a program to calculate molecular parameters and prepare tables written by K. Hirotsu and G. Van Duyne, Cornell University, 1985.Acknowledgment. We thank the Government of the Republic of Palau for a scientific research permit. We thank Dr Klaus Rützler, Smithsonian Institution, Washington, D.C. for identifying the sponge and Mary Kay Harper for performing additional bioassays. This research was supported by grants from the Sea Grant College Programs of California [Projects R/MP-30 to DJF) and R/MP-31 (to RSJ)] and New York (to JC) and the National Institutes of Health (CA 24487 to JC).  相似文献   

14.
Summary The chloride electrochemical potential difference between the inside of cells ofNitella translucens and some external solutions, where Cl has been progressively replaced by benzenesulphonate, has been measured by means of Ag-AgCl electrodes. It appears that benzenesulphonate moves into the cell by an electrogenic pump and that the uptake of Cl byNitella is not in contradiction with a carrier hypothesis.

This work was supported by grants from the F.N.R.S. and was carried out in the Biophysics Section of the Edinburgh University. We are indebted to Dr. E. J.Williams and Dr.Hogg for having sponsored this research and kindly provided the material.  相似文献   

15.
Summary Glutamine synthetase I was purified fromRhizobium sp. UMKL 20 following polyethylene glycol precipitation. The enzyme had a subunit molecular weight of 58 kd. Apparent Km values for ammonia and glutamate were 5.6 and 15.2 mM, respectively. Glutamine synthetase I activity was inhibited by several end products of glutamine metabolism. The purified enzyme was highly adenylylated (E n =8.5).Acknowledgment. I would like to thank Mr J. C. Lai for technical assistance. This work was carried out with the support of Vote F 153/79 from the University of Malaya.  相似文献   

16.
Summary Luffariellolide (2) is a sesterterpene from the Palauan spongeLuffariella sp. that has useful anti-inflammatory properties. In contrast with the irreversible action of manoalide (1) on phospholipase A2, luffariellolide (2) is a slightly less potent but partially reversible PLA2 inhibitor.30 December 1986Acknowledgment We thank Edward Luedtke, Elise Clason and Ellen Snideman for performing some of the assays reported above. The sponge was identified by Dr. Klaus Rützler, Smithsonian Institution, Washington, D.C. The research was supported by grants from Allergan Pharmaceuticals and the California Sea Grant College Program (Projects R/MP-30 and R/MP-31).  相似文献   

17.
Summary By means of closed-loop-stripping and subsequent GC analyses the diel periodicity of release of (Z)-11-hexadecenyl acetate, (E)-8-dodecenyl acetate, and (Z)-9-tetradecenyl acetate, the main constituents of the respective sex pheromone blends ofMamestra brassicae, Cryptophlebia leucotreta andSpodoptera sunia females, was determined.Pheromones, 64. For the 63rd contribution we have taken from: Szöcs, G., Toth, M., Bestmann, H. J., Vostrowsky, O., Heath, R. R., and Tumlinson, J. H., Z. Naturforsch.42c (1987) 165; Pheromones, 62: Bestmann et al.13.  相似文献   

18.
Little is known about the genetic control of phytotoxin production by plant pathogenic fungi. The production of host-selective toxins known to play a role in disease development has been genetically analyzed in three species ofCochliobolus. InC. heterostrophus, a single genetic locus with two alleles has been identified controlling the production of HMT-toxin. This locus appears to be at or near the breakpoint of a chromosome rearrangement. Single genetic loci have also been identified controlling the production of HC-toxin byC. carbonum and HV-toxin byC. victoriae. The locus inC. carbonum may be a cluster of tightly linked genes.  相似文献   

19.
Summary Allozyme electrophoresis was used to determine the hybrid parentage of the triploid parthenogenetic speciesCnemidophorus exsanguis. 19 of 33 loci were polymorphic inC. exsanguis and/or the 7 potential bisexual progenitors. It was determined from allele distributions thatC. exsanguis containes genomes form 3 different species, probablyC. costatus, C. inornatus andC. septemvittatus.Acknowledgments. We thank R.L. Bezy, W.M. Brown, A.E. Greer, C.S. Lieb, J.L. Patton and K.L. Wright for assistance in the field; the Departments of Game and Fish of Arizona and New Mexico and the Direccion General de la Fauna Silvestre, Mexico for providing collecting permits; and R.L. Bezy, H.W. Greene and D.B. Wake for discussions and criticisms. This research was supported in part by NSF Grants DEB 76-20599 and DEB 81-05615 and by a Research Fellowship in Herpetology from the Natural History Museum of Los Angeles County to DAG.  相似文献   

20.
Summary A new linear polyketide, Annonacin (I), has been isolated from active extracts of the stembark ofAnnona densicoma Mart. Annonacin (I) is highly cytotoxic and is active in an assay designed to detect antimitotic agents. The structure of (I) was determined by analysis of spectroscopic data.25 September 1986  相似文献   

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