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1.
In a previous study, cDNA microsatellite markers were described in apricot (Prunus armeniaca L.). Specific PCR primers were designed to amplify the microsatellite-containing regions from genomic DNA in different Prunus species. In the present work, cDNA microsatellite markers were developed in the hexaploid Prunus domestica L. species and polymorphism was ascertained in a segregating plum population. Co-dominant mendelian segregation of alleles was demonstrated and microsatellite polymorphism displayed up to 6 alleles per SSR locus per individual. Parentage lineage of three full-sib European plum cultivars (cv. Cacanska najbolja, Cacanska rana and Cacanska lepotica) was reconstructed by the analysis of the above nuclear SSR markers, completed by four chloroplastic microsatellite loci. The six most informative nuclear loci enabled discrimination between the three Cacak cultivars and unrelated individuals as well as the previously proposed parents, Wangenheim and Pozegaca. Data obtained support previous evidence that these cultivars originated from the Stanley cultivar. However, SSR analysis finally excluded Wangenheim as the other possible parent. Based on the results obtained with nuclear and chloroplast SSR loci, we propose the origin of those three Cacak cultivars in a cross between Stanley as the mother plant and Ruth gerstetter as the pollinator. Furthermore, we demonstrate the utility of these apricot SSR markers for genotype fingerprinting of the hexaploid plum cultivars.  相似文献   

2.
During chloroplast development in the primary leaves of Phaseolus vulgaris, the extractable activity of adenosine 5-phosphosulfate sulfotransferase increased ten-fold. When chloroplast development took place in air enriched with 3.5 l H2S·l-1 there was a decrease in adenosine 5-phosphosulfate sulfotransferase activity. Cyst(e)ine in concentrations up to 1 mM (in the external medium) did not affect the increase in adenosine 5-phosphosulfate sulfotransferase activity in intact plants. In plants with excised roots, 0.75 mM cyst(e)ine inhibited this increase. In green primary leaves, H2S or cyst(e)ine treatment resulted in a decrease of extractable adenosine 5-phosphosulfate sulfotransferase activity. In intact plants, this effect of cyst(e)ine was observed at a concentration of 1 mM, and in plants with excised roots, 0.25 mM had a comparable effect.In developing plants, the extractable activities of O-acetyl-L-serine sulfhydrylase (EC 4.2.99.9) and ribulosebisphosphate carboxylase (EC 4.1.1.39.) were not affected by H2S or cyst(e)ine.Abbreviations APS adenosine 5-phosphosulfate - APSSTase adenosine 5phosphosulfate sulfotransferase - BSA bovine serum albumin - DTE dithioerythritol - EDTA ethylenediaminetetra-acetic acid - OASSase O-acetyl-L-serine sulfhydrylase - PAPS adenosine 3-phosphate 5-phosphosulfate - POPOP 1,4 Di 2-(5-phenyloxazolyl)-benzene - PPO 2,5-diphenyloxazol - RubP ribulose-bisphosphate - RubPCase ribulosebiphosphate carboxylase This is no. 8 in the series Regulation of Sulfate Assimilation in Plants. The term cysteine is used when it is clear that cystine is not involved; cyst(e)ine is used for an undefined mixture of cysteine and cystine. The concentrations are expressed in all cases relative to cysteine  相似文献   

3.
Summary A ligninase gene has been cloned from a Phanerochaete chrysosporium genomic DNA library. Nucleotide sequencing of the gene has revealed that the ligninase structural gene contains 1116 bp of the protein-encoding sequence, of which 84 bp encode the signal peptide. The protein-encoding sequence is interrupted by eight introns which conform to the universal G-T/A-G splicing rule observed for the 3 and 5 intron boundaries. The putative eukaryotic regulatory sequences, i.e. CAAT and TATA box-like sequences, are present in the 5 flanking region.  相似文献   

4.
R. Huc  A. Ferhi  J. M. Guehl 《Oecologia》1994,99(3-4):297-305
Leaf gas exchange rates, predawn wp and daily minimum wm leaf water potentials were measured during a wet-to-dry season transition in pioneer (Jacaranda copaia, Goupia glabra andCarapa guianensis) and late stage rainforest tree species (Dicorynia guianensis andEperua falcata) growing in common conditions in artificial stands in French Guiana. Carbon isotope discrimination () was assessed by measuring the stable carbon isotope composition of the cellulose fraction of wood cores. The values were 2.7 higher in the pioneer species than in the late stage species. The calculated time integratedC i values derived from the values averaged 281 mol mol–1 in the pioneers and 240 mol mol–1 in the late stage species. The corresponding time-integrated values of intrinsinc water-use efficiency [ratio CO2 assimilation rate (A)/leaf conductance (g)] ranged from 37 to 47 mmol mol–1 in the pioneers and the values were 64 and 74 mmol mol–1 for the two late stage species. The high values were associated—at least inJ. copaia—with high maximumg values and with high plant intrinsinc specific hydraulic conductance [Cg/(wmwp], which could reflect a high competitive ability for water and nutrient uptake in the absence of soil drought in the pioneers. A further clear discriminating trait of the pioneer species was the very sensitive stomatal response to drought in the soil, which might be associated with a high vulnerability to cavitation in these species. From a methodological point of view, the results show the relevance of for distinguishing ecophysiological functional types among rainforest trees.  相似文献   

5.
Summary The meiotic identification of nine pairs of chromosomes at metaphase I of meiosis of Triticum aestivum (B genome, 4A and 7A) has been achieved using a Giemsa C-banding technique. As a result, the analysis of the pairing of each chromosome arm in disomic and monosomic intervarietal hybrids between Chinese Spring and the Spanish cultivar Pané 247 could be carried out. Differences in the chiasmata frequencies per chromosome arm cannot be explained on the basis of relative arm lengths only. Possible effects of arm-to-arm heterochromatic differences on meiotic pairing are discussed.  相似文献   

6.
Summary A frequency-time domain 3D NMR technique has been developed for measurement of heteronuclear coupling constants in oligonucleotides employing a combination of COSY andJ-resolved techniques. The method employs frequency-selective excitation to generate the 1 axis and 2D FT to generate the 2 and 3 axes. The procedure yields high resolution, especially along the 1 axis. The technique is demonstrated on a dinucleotide.  相似文献   

7.
Six specimens (2 flexion larvae: 9.5–10.4mm in notochord length; 4 postflexion larvae: 12.3–18.2mm in standard length) collected from the western North Pacific are tentatively ascribed to the genus Uncisudis of the tribe Lestidiini of the subfamily Paralepidinae (Paralepididae) in sharing remarkably elongate and filamentous pelvic fin rays, their tips reaching the origin of the anal fin. They are described as Uncisudis posteropelvis sp. nov. in uniquely having the insertion of pelvic fins closer to the origin of anal fin than to the posterior end of dorsal fin base among lestidiine species. Addition to this character, the new species has remarkably elongate and filamentous dorsal fin rays, the short distance between anus and origin of anal fin (4.2–6.1% of standard length, SL), the posteriorly located pelvic fins (prepelvic length 69.4–71.5% SL), dorsal fin rays 10, anal fin rays 28–29, myomeres 41–42+38–40=80–81 (vertebrae 38+41=79), and peritoneal pigment spots 11–12. The occurrence of larvae differing in pigment pattern from the present new species suggests another undescribed species of Uncisudis in the western South Pacific.  相似文献   

8.
The reliability of parasitic water-mites as criteria of a nulliparous condition has been investigated in ten species of mosquito in Uganda. Larvae of two kinds of hygrobatid-type mites, when alive, were found only on nulliparous mosquitoes; but living larvae of two other hygrobatids occurred on a small proportion of pars also. Larvae of thyasid-type mites occurred at least as often on pars as on nullipars. Different types of scars caused by mites can provide information concerning the original infestation rate of a population and also the likelihood that an individual female is parous.In the species of mosquito studied, the infestation rate of nullipars sometimes exceeded 80%, but was usually less than 20%.
Zusammenfassung An 10 Mückenarten von Uganda wurde untersucht, inwieweit schmarotzende Wassermilben zuverlässig sind zur Unterscheidung alter Mücken (d.h. solcher, die Eier gelegt haben) von jungen Mücken (d.h. solchen, die noch keine Eier gelegt haben). Untersuchung der Ovarien ermöglichte es, weibliche Mücken in alte und junge Individuen einzuteilen. Zu diesem Zweck wurden mehr als 20.000 Mücken seziert.Der Lebenszyklus der an Mücken schmarotzenden Wassermilben wird besprochen. Die Larven zweier Arten von hygrobatischen Wassermilben wurden lebend nur an jungen Mücken gefunden; lebende Larven von zwei anderen hygrobatischen Milbenarten kamen auch an einem kleinen Teil von alten Mücken vor. Larven von thyasischen Milben wurden mindestens ebenso oft an alten wie an jungen Mücken gefunden. Deshalb war es wichtig, den Milbentypus festzustellen und zu erkennen, ob die Milben lebendig oder tot waren.Die Infektion der Mücken durch fünf der gewöhnlichen Wassermilben-Species wird beschrieben. Es hängt von der Milben- und von der Wirts-Art ab, welche Stelle die Milben zum Anheften wählen. Verschiedene Typen der durch die Milben verursachten Narben informieren über die ursprüngliche Befallsrate einer Bevölkerung und auch über die Wahrscheinlichkeit, dass die Mücke alt ist. Die Stärke der Infektion ändert sich bei einer einzigen Mückenart von Monat zu Monat beträchtlich. Manchmal sind über 80% der jungen Mücken befallen, im allgemeinen aber weniger als 20%.Bei Culex annulioris, bei dem die hygrobatischen Larven sich auf die jungen Mücken beschränken, ist der Stechzyklus eines befallenen Weibchens derselbe wie dem aller jungen Weibchen. Deshalb kann der Stechzyklus der jungen Mücken, nicht aber der der alten, direkt von den untersuchten milbentragenden Weibchen abgeleitet werden.Es wird gefolgert, dass bestimmte Wassermilben des hygrobatischen Typus für eine schnelle Diagnose von jungen Mücken nützlich sind; vorher muss jedoch in ausgedehnten Versuchen der Grad ihrer Zuverlässigkeit für jede Wirtsart festgelegt werden.
  相似文献   

9.
In the female grasshopper Gomphocerus rufus mating elicits secondary defense which makes remating impossible. The behavioral change is caused by the liquid white secretions, proteins of less than 90 kD, which are produced by the white tubuli of the male's accessory glands. Experimental injection of the white secretions directly into the spermathecal duct of receptive virgins provokes secondary defense instantly whereas sperm transfer had no such effect. Secondary defense is also released by eggs entering the oviducts and excerting pressure against the oviductal walls on their way to oviposition.  相似文献   

10.
Apostichopus (= Stichopus) japonicus blastulae and gastrulae were acclimated for 18 h to salinities of 32 (control), 24 and 22 (the lower limit of the range of tolerance), and 20 (below the range of tolerance). Acclimation to 20 resulted in the appearance of teratic larvae, most of which subsequently died. Acclimation to 24, 22, and 20 led to a shift in the range of tolerance of the larvae at further stages of development. With a decrease in salinity, acclimated larvae developed more successfully than unacclimated larvae. Acclimated larvae attained the pentactula stage and settled at a salinity range of 32–20; unacclimated larvae, at 32–22. At different stages of development, acclimated larvae survived greater decreases in salinity than unacclimated larvae. The acclimation effects could be traced up to metamorphosis and settling, i.e., two weeks after the end of the acclimation process.  相似文献   

11.
Data on both the colloid size distributionpresent in freshwaters and the extent to whichtrace metal ions associate with the differentsize fractions within the so-called dissolved phasein these systems are examined. Several keyfeatures are identified: (i) division of totalmetal into particulate and dissolved fractions via a single ca. 450 nm filtrationprocedure provides no useful information, (ii)within the dissolved fraction, a continuum ofparticle sizes exists in the colloidal sizerange in freshwaters, (iii) for the tracemetals Cu, Cd, Zn, Cr, Co, and Ni, the greatestproportion of dissolved trace metals are in the low molecular mass fraction, together withthe largest proportion of DOC, (iv) in allrivers, and in lakes with a low DOC content,the predominant determiner of the sizedistribution of trace metals is the lowermolecular size, more strongly complexing,pedogenic organic matter fraction.  相似文献   

12.
A new type of exterilium larvae referable to Leptobrotula (Ophidiiformes: Ophidiidae) is described on the basis of two specimens (20.7+mm and ca. 35.4mmSL) collected from the tropical Indo-Pacific. They are characterized, in particular, by several elongated anterior dorsal fin rays supported by the large dorsal pterygiophores and the exterilium gut bearing filamentous appendages along the ventral border. It is suggested from larval evidence that Leptobrotula forms a distinct lineage with Brotulotaenia and Lamprogrammus, which may be placed in an expanded Brotulonaeniinae.  相似文献   

13.
A novel syrup containing neofructo-oligosaccharides was produced from sucrose (Brix 70) by whole cells of Penicillium citrinum. The efficiency of fructo-oligosaccharides production was more than 55% and those of the main carbohydrate components, 1-kestose (Fruf 21Fruf 21 Glc), nystose (Fruf 21Fruf 21 Fruf 21 Glc) and neokestose (Fruf 26 Glc12 Fruf), were 22, 14 and 11%, respectively.  相似文献   

14.
Summary None of the Agrobacterium tumefaciens and A. rubi strains tested produces detectable amounts of -galactosidase although they are capable of utilizing lactose as sole source of carbon. This opportunity was taken to investigate the expression of lac transposon Tn951 (Cornelis et al. 1978) in Agrobacterium with the ultimate goal of using this system to investigate alien gene expression. When the transposon was introduced with the help of a broad-host range plasmid, RP1, the transconjugants produced significant quantities of -galactosidase which was inducible by isopropyl--D-thiogalactopyranoside. Tn951 was capable of restoring the Lac+ phenotype to an A. tumefaciens mutant not capable of using lactose. Cellobiose, a known inducer of aldohexopyranoside: cytochrome c oxidoreductase which regulates the characteristic 3-ketolactose production in Agrobacterium: van Beeumen and De Ley (1968), had no effect on -galactosidase activity.Abbreviations NCPPB National Collection of Plant Pathogenic Bacteria, Harpenden - km kanamycin resistance - str streptomycin resistance - rif r rifampicin resistance  相似文献   

15.
Interaction behaviors of larvae of Simulium vittatumand S. decorum,behaviors that directly affect other black fly larvae, were observed under laboratory and field conditions. Experiments with S. vittatumshowed that changing the larval density or the amount of available food resulted in only minor changes in interaction behavior. Reduction in larval density resulted in shorter interactions, although the distance between the silkpads of the interacting larvae remained the same. Reduction in food availability resulted both in shorter interactions and in a shorter mean distance between silkpads during an interaction. The actor (initiator of an interaction) in both species was more likely to probe or make a silkpad, while the reactor was more likely to push or attack the actor's silkpad. In the field, S. vittatumcommonly occur in spaced dispersion patterns, and S. decorumin clumped patterns. In the laboratory, both species formed spaced dispersion patterns and showed similar interaction behaviors. Field observations suggest that the dispersion pattern exhibited depends on microhabitat rather than species. The actors' head locations, which indicate potential larval attachment sites, moved downstream and away from the reactors during an interaction. Interaction behavior, therefore,produces the spaced dispersion pattern exhibited by these larvae.  相似文献   

16.
The life cycles of two separate populations (colonies A and B) of the rabbit tick, Haemaphysalis leporis-palustris, were studied under laboratory conditions. Domestic New Zealand rabbits, Oryctolagus cuniculus, and wild rabbits, Sylvilagus brasiliensis, were used as hosts for ticks from colony B and only O. cuniculus rabbits were used as hosts for ticks from colony A. Developmental periods were observed in an incubator at 27±1°C and RH 90±5%. Larvae from colonies A and B fed for 8.0±3.7 days and 8.5±1.3 days, respectively, on O. cuniculus. On S. brasiliensis larvae from colony B fed for 7.2±1.3 days. Nymphs from colony A fed for 8.1±1.4 days on O. cuniculus and nymphs from colony B fed for 8.1±1.0 days on S. brasiliensis. Only one engorged nymph from colony B was recovered from O. cuniculus. Females from colony A fed for 20.9±5.9 days on O. cuniculus and females from colony B fed for 18.6±2.4 days on O. cuniculus and 18.7±3.7 days on S. brasiliensis. Engorged larvae from colony A required 13.7±3.7 days to molt while engorged larvae from colony B required 11.8±3.0 and 11.5±1.8 days to molt, after having fed on O. cuniculus and S. brasiliensis, respectively. Engorged nymphs from colonies A and B required 16.3±1.9 days and 14.7±1.4 days to molt, respectively. Engorged females from colonies A and B required 4–7 and 3–5 days, respectively, to start oviposition. Mean egg incubation periods lasted for 33–34 days. For ticks from colony B, host species accounted for significant differences (p<0.05) in larval and nymphal feeding periods, oviposition weights and CEIs. Significant differences (p<0.05) between the two colonies when ticks fed on O. cuniculus were observed for larval and nymphal feeding and premolt periods, engorged female and oviposition weights and conversion efficiency indexes (CEI). S. brasiliensis were always a more suitable host for H. leporis-palustris than O. cuniculus. Significantly more larvae and nymphs engorged and molted when fed on S. brasiliensis (p<0.001). Females fed S. brasiliensis were more successful to lay fertile eggs and showed the highest engorged and egg mass weights, and the highest CEIs. Data of H. leporis-palustris fed on wild rabbits (one of its natural host species) are reported for the first time.  相似文献   

17.
The main carotenoid of Flavobacterium strain R1560 has been identified as (3R,3R)-zeaxanthin. Also present were small amounts of 15-cis-phytoene, phytofluene, -carotene (7,8,7,8-tetrahydro-, -carotene plus 7,8,11,12-tetrahydro-, -carotene), neurosporene, lycopene, -zeacarotene, -carotene, -carotene, -cryptoxanthin, rubixanthin, 3-hydroxy--zeacarotene and several apo-carotenals. Zeaxanthin production was inhibited by nicotine (10 mM), and lycopene and rubixanthin accumulated. The biosynthesis of zeaxanthin is discussed in terms of pathways and also of half-molecule reaction sequences. The presence of zeaxanthin may be a characteristic of a group of Flavobacterium species, and may thus be useful in the taxonomic classification of these organisms.  相似文献   

18.
Syntheses of the following compounds are described: 6-(Trifluoroacetylamino)hexyl 2-acetamido-2,6-dideoxy--d-glucopyranoside and 2-acetamido-2-deoxy--d-xylopyranoside, two allyl 2-acetamido-2-deoxy--d-glucopyranosiduronic acid derivatives, and several allyl 2-acylamido-2-deoxy--d-glucopyranosides having different acyl groups. These and other compounds were used as inhibitors in the binding assay for the chicken hepatic lectin specific forN-acetylglucosamine. We found that: 1) The inhibitory potency ofN-acylglucosamine derivatives decreased progressively with increase in the size of acyl group, 2) absence of either 3-or 4-OH group ofN-acetylglucosamine lowered the binding affinity more than 100-fold, and 3) the presence of a negatively charged group (carboxylic acid) at the C-6 position did not lower the affinity. The first two items are similar to the mammalian hepatic galactose/N-acetylgalactosamine lectins, but the last item is in a strong contrast to the mammalian lectins.Abbreviations XyLNAc N-acetyl-d-xylosamine - BSA bovine serum albumin - NeuAc N-acetylneuraminic acid - GlcNAc34-BSA amidino-type neoglycoprotein [6] containing on the average 34N-acetylglucosaminyl residues per BSA molecule  相似文献   

19.
Transgenic animals secreting individual chains and assembled fibrinogen were produced to evaluate the capacity of the mammary gland for maximizing assembly, glycosylation and secretion of recombinant human fibrinogen (rhfib). Transgenes were constructed from the 4.1kbp murine Whey Acidic Protein promoter (mWAP) and the three cDNAs coding for the A, B and fibrinogen chains. Transgenic mice secreted fully assembled fibrinogen into milk at concentrations between 10 and 200 g/ml, with total secretion of subunits approaching 700 g/ml in milk. Partially purified fibrinogen was shown to form a visible and stable clot after treatment with human thrombin and factor XIII. The level of assembled fibrinogen was proportional to the lowest amount of subunit produced where both the B and chains were rate limiting. Both the B and chains were glycosylated when co-expressed and the degree of saccharide maturation was dependent on expression level, with processing preferred for chains over B chains. Also, the subunit complexes 2, A2 and the individual subunits A, B and were found as secretion products. When the B was secreted individually, the glycosylation profile of the molecule was of a mature complex saccharide indicating recognition of the molecule by the glycosylation pathway without association with other fibrinogen chains. To date secretion of B chain has been not observed in any cell type, suggesting that the secretion pathway in mammary epithelia is less restrictive than that occurring in hepatocytes and other cells previously used to study fibrinogen assembly.  相似文献   

20.
Hybridizations ofElymus nutans andE. jacquemontii were carried out with one species ofPseudoroegneria (S genome), and 20Elymus species, each containing either of the SH, SY, SYH, or SYW genomes. Chromosome configurations were analysed at metaphase I of the two target taxa and their interspecific hybrids. It is concluded that (i)E. nutans is an allohexaploid containing the SYH genomes, andE. jacquemontii is an allotetraploid having the SY genomes; (ii) the genomic affinity is associated with the geographic distance between the species studied; (iii) minor genomic structural rearrangements have occurred within the hexaploid taxon ofE. nutans.  相似文献   

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