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1.
Taxonomic analysis of a group of morphologically similar ponyfishes (Perciformes: Leiognathidae) establishes the Leiognathus splendens complex comprising four valid species: L. jonesi James, 1971, widely distributed in the Indo-West Pacific, from Mauritius to Papua New Guinea, north to Hainan I. (China), and south to Brisbane, Australia; L. kupanensis sp. nov., currently known only from Kupang, Timor, Indonesia; L. rapsoni Munro, 1964, currently known only from India, Indonesia, and Papua New Guinea, and L. splendens Cuvier, 1829, widely distributed in the eastern Indian and western Pacific oceans, from India to Papua New Guinea, and from southern Japan to northern Australia. The L. splendens complex can be defined by the following combination of characters: body depth 42–60% of standard length; mouth protruding downward; slender, minute teeth uniserially on jaws; lower margin of orbit above the horizontal through the gape when mouth closed; breast almost completely scaled; lateral line complete, and a dark blotch on top of spinous dorsal fin. Diagnostic characters of the members are as follows: L. jonesi—anterior dorsolateral body surface with a semicircular naked area on nape, and a paler dark blotch on spinous dorsal fin; L. kupanensis—anterior dorsolateral body surface widely naked; L. rapsoni—cheek scaled; L. splendens—anterior dorsolateral body surface completely scaled and a jet black blotch on spinous dorsal fin.  相似文献   

2.
An esterase locus (Est-2), coding for carboxylesterase, and an acid phosphatase locus (Acph) were genetically studied by agar gel electrophoresis in the mosquito Aedes (Finlaya) togoi. The Est-2 and Acph variants occur as a monomer and a dimer, respectively. Both enzyme loci are linked to the sex locus (M) and s (straw-colored larva); the gene arrangement and recombination distances were Est-2—12.6%—s—31.7%—M—2.9%—Acph—3.2%—Est-3. The Est-3 locus was previously shown to code for carboxylesterase.This work was supported by Grant AI 16983-02 from the National Institutes of Health, Bethesda, Md.  相似文献   

3.
Summary The linkage relationship of a nuclear male sterile locus, ms-10, was tested with two enzyme marker loci known to be on the same chromosome (long arm of chromosome 2). The results indicate the gene order is Est-1 — 18 cM — Prx-2 — 1.5 cM — ms-10. The linkage intensity of ms-10 and Prx-2 (1.5 cM) suggests that Prx-2 might provide a selectable marker for male-sterility. In accordance with this idea, the ms-10 allele was placed in cis with a rare-allele of Prx-2 (Prx-2 1). Selection on the basis of the codominant Prx-2 1 allele should allow for more rapid and efficient transfer of the recessive male sterile allele into an array of genetic backgrounds, thus promoting its use in hybrid seed production.  相似文献   

4.
Summary We find that recombination between two alleles of the maize A1 locus that contain transposon insertions at known molecular positions can occur at 0.04–0.08 cM per kbp (centimorgan per kilobase pair), which is two orders of magnitude higher than the recombination rate for the whole maize genome. It is however, close to the rates found within the bronze locus, another maize structural gene for which both genetic and molecular data are available. This observation supports the idea that the genome consists of regions that are highly recombinogenic — in some cases, at least, structural genes — interspersed with regions that are less recombinogenic.  相似文献   

5.
Oviposition behaviour of Meligethes aeneus F. (Coleoptera: Nitidulidae) is characterised and quantified on four different plant species. Six behavioural components are identified: W—walking, WA—walking with abdomen on surface, R—resting, B—biting, AOH—placing abdomen over the bite hole and OVI—oviposition. Comparison of host acceptance behaviours on Brassica napus L., Brassica juncea (L.) Czern, Brassica nigra (L.) Koch and Sinapis alba L. showed that S. alba was accepted as a host only after a long exposure to the plant. Behaviour on the Brassica species was similar, however on B. nigra beetles spent a high proportion of time actually ovipositing. We conclude that important cues for oviposition are located both on the bud surface and inside the bud.  相似文献   

6.
Summary Allozyme polymorphisms of nine enzymes — aspartate aminotransferase (AAT), diaphorase (DIA), esterase (EST), formate dehydrogenase (FDH), -galactosidase (GAL), -glucosidase (GLU), malate dehydrogenase (MDH), malic enzyme (ME), and peroxidase (PRX) — were described in chick-pea (Cicer L.). Thirteen isozyme loci, Aat-c, Dia-4, Est-2, Est-4, Est-10, Fdh, Gal-2, Gal-3, Gal-4, Glu-3, Mdh-2, Me-2, and Prx-2, were genetically defined. Alleles of each of these isozyme loci expressed codominantly in heterozygotes and exhibited a codominant, single-locus segregation ratio in F2. The loci Est-2, Mdh-2, and Me-1 were expressed only in flower. Linkage relations were determined for these 13 and several previously defined isozyme loci. The following new genetic linkages were identified: Pgm-p (locus for plastid phosphoglucomutase) — Est-10; Ald-p1 (one of the duplicate loci for plastid aldolase) — Glu-3Gal-2Est-2,3; Gal-3Aco-m (locus for mitochondrial aconitase) — Prx-2,3; Gpi-c (locus for cytosolic glucosephosphate isomerase) — Fdh; and Est-4Me-1. This study provides further confirmation on the existence of several conserved linkage groups among Cicer, Pisum, and Lens.  相似文献   

7.
Summary Alpha-IPM synthase catalyzes the first committed step in leucine biosynthesis in the yeast S. cerevisiae. LEU4 is known to encode this enzyme activity. A second gene, LEU5, has been proposed to encode a second enzyme with this activity.We cloned LEU5 and genetically defined the locus. LEU5 maps to chromosome VIII and is tightly linked to CEN8.Five different mutations in LEU5 were analyzed: a sitedirected deletion and a disruption, as well as three distinct mutations produced by chemical mutagenesis. In a leu4 background, each leu5 mutation causes a Leu — phenotype; in a LEU4 background, none of the mutations alters the Leu+ phenotype. This shows that LEU5 is not essential for leucine biosynthesis. In either a leu4 or LEU4 background, each leu5 mutation causes a glycerol — phenotype. This operationally defines LEU5 as a PET gene.Two distinct suppressors of the Pet — phenotype of leu5 strains have been isolated. These suppressors revert the Pet — phenotype of each of four mutant leu5 alleles that were tested. Suppression occurs regardless of the allele at LEU4. Moreover, the suppressors co-revert the Leu — phenotype for each of the four leu5 mutations that is combined with a leu4 allele. This establishes the presence of a gene other than LEU5 that encodes a second alpha-IPM synthase. Further analysis provided no evidence for synthase activity that is encoded by LEU5.Abbreviation EMS ethylmethane sulfonate - IPM isopropylmalate - NPD nonparental ditype - PD parental ditype - TT tetratype  相似文献   

8.
Phylogenetic relationships of ten wild species and several cultivars ofForsythia were reconstructed based on the chloroplast (cp) DNA variation. A total of 216 cpDNA variants, 44 of which were potentially phylogenetically informative, was detected using 24 restriction endonucleases. Phylogenetic analysis usingFontanesia andAbeliophyllum as outgroups revealed four well defined species groups in the genus: 1)F. suspensa, 2)F. europaea — F. giraldiana, 3)F. ovata — F. japonica — F. viridissima, and 4)F. koreana — F. manshurica — F. saxatilis. The amount of support for each monophyletic group was evaluated by various methods including character number, decay analysis, parsimony bootstrapping, Neighbour-Joining (NJ) — bootstrapping, NJ-jackknifing, and the topology-dependent permutation tail probability (T-PTP) test. The data do not support the hybrid origin ofF. intermedia fromF. suspensa andF. viridissima. The disjunctly distributed European species,F. europaea, was identified as a sister species of the ChineseF. giraldiana and it was probably derived through recent long distance dispersal.  相似文献   

9.
Four species of turbellarian temnocephalan symbionts (Platyhelminthes: Temnocephalida) are reported for the first time from the external surfaces of Cherax quadricarinatus, a freshwater crayfish from northern Australia. Three of these species — Temnocephala rouxii Merton, 1913, Notodactylus handschini (Baer, 1945), and Diceratocephala boschmai Baer, 1953 — are known previously from related crayfish in New Guinea. The newly discovered fourth species, Decadidymus gulosus n. gen., n. sp., has an unusual combination of characters linking it with both the Temnocephalidae and the Scutariellidae. Together the four species possess an array of characters that challenges current concepts of families in the order. D. boschmai has an almost completely ciliated epidermis, a feature otherwise unknown in the order.  相似文献   

10.
Compositae (Asteraceae) are remarkably homogenous in basic type of inflorescence, flower and fruit. TheCichorioideae are more closely related to the other groups than usually realized. The classical concept of theAsteroideae tribes has been confirmed in general, but recent investigations (using palynology, carpology, phytochemistry etc.) suggest numerous corrections, and some genera (e.g.Liabum, Echinops, Tarchonanthus, Arnica) do not fit into the scheme. The tribes ofAsteroideae may be divided into two groups characterized by several common characters and common tendencies. The oldest reliable fossils are known from the borderline Oligocene/Miocene. Looking for the nearest relatives,Campanulales (incl.Calyceraceae) and—because of interesting phytochemical agreements—Araliales have to be discussed.This paper was read at the XIIth International Botanical Congress, Leningrad, July 1975.  相似文献   

11.
In contrast to low diversity seen in many Australian rainforest squamate genera, sclerophyll adapted groups—such as Carlia—show signs of faster diversification. Here we expand upon a previous single-locus mitochondrial DNA phylogenetic study of Carlia which described a major polytomy at an intermediate level of divergence. With additional mtDNA data, two nuclear intron loci and comprehensive taxonomic coverage, we provide support, congruent across loci, for the existence of three major clades. In doing so we recognise three genera for the ‘Carlia group of skinks’: clade 1, Carlia Gray, 1845; 2, Lygisaurus De Vis, 1884 (includes all species formerly known as Lygisaurus, and also includes C. parrhasius); 3, Liburnascincus Wells and Wellington, 1984 (consisting of three boulder-dwelling species). Remaining regions of low bootstrap and posterior probability support are associated with short internodes and apparent conflict among loci, as inferred by Partition Branch Support. Likelihood-based diversification-rate analysis rejects constant rate models, and indicates that Carlia underwent a period of relatively rapid diversification early in the evolution of the group, a rate 3–4 times faster than subsequent rates, and faster than comparable wet forest skinks.  相似文献   

12.
15 new species are described: Sect.Sclerocalycinae:S. farsistanica, S. stapfii. — Sect.Spergulifoliae:S. paktiensis. — Sect.Auriculatae:S. caroli-henrici, S. daënensis, S. gertraudiae, S. nizvana, S. oligophylla, S. persepolitana, S. pseudaucheriana, S. pseudonurensis, S. renzii, S. salangensis, S. sojakii. — Sect.Brachypodae:S. rasvandica. — All the new species are from Iran with exception ofS. paktiensis andS. parvanica which are from Afghanistan.
Florae Iranicae praecursores 46–60. — Praecursores praecurrentes in Pl. Syst. Evol.142: 239–246 (1983).  相似文献   

13.
An electrophoretically detectable variant of lactate dehydrogenase-2 in Mus musculus has been found and used to locate the structural gene, Ldh-2, on chromosome 6. Gene order and recombination frequencies are estimated as Sig—36.0±4.8—Lc 21.0±4.1—Mi wh—20.0±4.0—Ldh-2.  相似文献   

14.
Electrophoretic analysis of the developmental stages and tissues of Anopheles albimanus showed that qualitatively similar allozymes of aconitase (Acon-2) occur at all stages, and the enzyme is widespread in every larval and adult tissues. Relative heat stabilities of the allozymes were investigated by electrophoresis of heated aqueous extracts and by heating the enzyme in situ in acrylamide gels after electrophoretic separation in Tris-citrate and Tris-maleate buffer systems. The pupal aconitase in the crude extract is more stable to heat than the larval and adult enzyme. The presence of citrate ions in the gel increased the stability of aconitase to heat. Studies of substrate specificities indicated that cis-aconitic acid is the best substrate but citric acid can also serve as a substrate. Zymograms developed with isocitric acid as a substrate showed no aconitase electromorphs and produced only isocitrate dehydrogenase bands. Aconitase has a pH optimum of 8.0 and this enzyme is completely inhibited if treated in situ with ethylenediaminetetra-acetic acid (EDTA), p-chloromercuribenzoate (PCMB), and urea at concentrations higher than 5mm, 5×10–5 m, and 2 m, respectively. Acon-2100 and Acon-2105 do not respond differently to the above treatments. Genetic crosses involving a holandric translocation, pericentric inversions, visible mutants, and allozyme markers were analyzed to map the aconitase (Acon-2) locus on the left arm of chromosome 3. The gene sequence (and map distances) on 3L is centromere—esterase-8 (Est-8)—2—esterase-4 (Est-4)—25—esterase-2 (Est-2)—9—Acon-2—5—phosphoglucomutase (Pgm)—7—esterase-6 (Est-6).  相似文献   

15.
A pot experiment was conducted in the green house to investigate the establishment of phosphate solubilizing strains of Azotobacter chroococcum, including soil isolates and their mutants, in the rhizosphere and their effect on growth parameters and root biomass of three genetically divergent wheat cultivars (Triticum aestivum L.). Five fertilizer treatments were performed: Control, 90 kg N ha—1, 90 kg N + 60 kg P2O5 ha—1, 120 kg N ha—1 and 120 kg N + 60 kg P2O5 ha—1. Phosphate solubilizing and phytohormone producing parent soil isolates and mutant strains of A. chroococcum were isolated and selected by an enrichment method. In vitro phosphate solubilization and growth hormone production by mutant strains was increased compared with soil isolates. Seed inoculation of wheat varieties with P solubilizing and phytohormone producing A. chroococcum showed better response compared with controls. Mutant strains of A. chroococcum showed higher increase in grain (12.6%) and straw (11.4%) yield over control and their survival (12—14%) in the rhizosphere as compared to their parent soil isolate (P4). Mutant strain M37 performed better in all three varieties in terms of increase in grain yield (14.0%) and root biomass (11.4%) over control.  相似文献   

16.
Rumex sect.Axillares first described by the author in 1937 is known to be represented in N. America by 20 endemic species. From S. America only five species, all endemic, were previously known; this number is raised in the present revision to 15. Outside America there exist small groups of endemic species in S. Africa and in the islands of Hawaii as well as in Australia and scattered single species in C. Africa, on the remote Atlantic islands of Tristan de Cunha and Gough Island, and in eastern Asia.—In Europe the section is completely absent, except for three American species which occur as rare aliens. TheAxillares are not only morphologically well-characterized by their growth—no leaf rosettes, flowering period practically unlimited by formation of later flowering axillary shoots, flowers often monoecious—but also by their genetic structure expressed by a different behaviour in hybridization. Hybrids are frequent between species of sect.Rumex (syn.Simplices) and are easy to recognize by their sterility which results in a certain peculiarity in habit. In contrast, no spontaneous hybrids are known with certainty among species of sect.Axillares. Most artificial hybrids are fairly fertile. So far only three hybrids between species of the two sections have been known. Three more have been found by the author in Chile, all being highly sterile and showing the growth characteristics resulting from sterility as occur in hybrids between species of sect.Rumex.
Resumen Rumex secciónAxillares fue descrito por primera vez por el autor en 1937. Se conoce en América del Norte con 20 especies endémicas. De América del Sur se conocían sólo 5 especies, todas ellas endemicas; este número asciende a 15 en la presente revision. Fuera de las Américas se encuentran pequeños grupos de especies endémicas en Sudáfrica, en las Islas de Hawaii y en Australia; especies aisladas se encuentran en Africa Central, en las lejanas Islas Atlánticas de Tristan de Cunha y Gough Island y en Asia Oriental. La sección no tiene representantes en Europa, con excepción de tres especies americanas introducidas, poco frecuentes. La secciónAxillares se caracteriza bien, tanto morfológicamente por su forma de creciemiento—sin rosetas foliares, período floral prácticamente ilimitado por la formación de inflorescencias axilares parciales, flores a menudo monoicas—como por su estructura genética que se manifiesta en un comportamiento diferente de hibridación. Híbridos son frecuentes en las especies de la secciónRumex (syn.Simplices) y reconocibles por su esterilidad que se expresa en cierta particularidad del habito. Al contrario, no hay seguridad de híbridos espontáneos en la secciónAxillares. La mayor parte de los híbridos artificiales son totalmente fértiles. Hasta ahora se conocían solo tres híbridos entre las especies de ambas secciones. Otros tres han sido encontrados por el autor en Chile. Todos completamente estériles y con las características de hábito típicas resultantes la esterilidad, como ocurre en los híbridos de la secciónRumex.
  相似文献   

17.
A new and rapid procedure has been developed for the isolation of the bacteriochlorophyll a-containing Fenna—Matthews—Olson (FMO)-protein from green sulfur bacteria. Polyclonal antibodies raised against the FMO-protein of Chlorobium (Chl.) tepidum were employed in the preparation of an antibody column utilizing immobilized protein A as the matrix. The antibody column afforded essentially a one-step purification process, resulting in preparations that were free from contaminating pigments and proteins. This was evidenced by absorption spectroscopy, SDS—PAGE, and fluorescence emission.This revised version was published online in October 2005 with corrections to the Cover Date.  相似文献   

18.
The appendages of an insect are subdivided into distinct segments or podomeres. Many genes responsible for the regionalization of the growing limb into subdomains have been isolated from Drosophila. So far, only one gene is known in the leg that is solely required for specifying the distal-most pattern element—the pretarsal claw. In Drosophila, the gene aristaless is expressed in the centre of the antennal and leg imaginal disc that represents the most distal position of appendages, and in a proximal region. When Drosophila aristaless function is impaired, antennae and legs develop without their distal-most structures—the arista and the claw. We describe here the analysis of aristaless in the beetle Tribolium—an insect that shows a different, more ancestral mode of appendage formation than Drosophila. In Tribolium, appendages grow out continuously during embryogenesis, and no imaginal discs are formed. Tribolium aristaless (Tc-al) expression starts midway during appendage elongation, and is seen in a distal and a proximal position of head and trunk appendages. At the end of embryogenesis, Tc-al is seen in four expression domains in the leg, in the dorsal epidermis, and ventrally in every segment in lateral groups of cells, presumably the histoblasts. Like in the Drosophila adult, Tc-al is required in the larva for the formation of the most distal structures of the leg and the antenna as revealed by RNAi experiments. We conclude that aristaless is evolutionarily robust, meaning that it has retained its expressional and functional characteristics, although a heterochronic change of the process of appendage elongation took place towards the evolution of the highly derived diptera.Edited by D. Tautz  相似文献   

19.
Populations of the annualPhaseolus sublobatus from different ecogeographical zones are genetically differentiated. In twelve populations from the western ghats (Maharashtra range) chasmogamous flowers are arranged in peduncled capitate racemes borne in leaf axils of higher nodes. One population (Poona Race S4) has additional inflorescences, also with chasmogamous flowers, on the main axis between the cotyledonary node and the ground. When the pods of these flowers ripen, the inflorescence gradually coils and, eventually, gets bury the fruits in the soil. This phenomenon is not known in any other plant.—The seed-coat patterns as revealed by SEM, and germination behaviour of both aerial and subterranean seeds are similar, and both types of seeds lack dormancy.—Heavy seed predation selection pressure is probably the principal cause for the evolution of fruit dimorphism inP. sublobatus. The origin of geocarpy in relation to fruit dimorphism and seed predation is discussed.  相似文献   

20.
Laboratory trials were performed to screen the potentials of four herbicides — PARAQUAT, DIQUAT, TOK E-25 and DALAPON — for the chemical control of Salvinia molesta. The herbicides were applied as aerial sprays, and their phytotoxic effects were assessed by visual estimation. Paraquat and Diquat have been found to be the more promising.The toxicities of the four herbicides were tested on three aquatic organisms associated with the plant in the aquatic environment —larva of Nymphula responsalis, Rasbora trilineata and Poecilia reticulata. An attempt was made to correlate the toxicological results with the application rates of the herbicides in terms of safety factors. TOK E-25 has been found to be most toxic, the others being relatively safe.  相似文献   

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