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61.
Strain RB1401 contains a plasmid with a fusion between the upper pathway promoter of the TOL plasmid xyl genes and a lux gene cassette. Bioluminescence activity appeared in the early period of biodegradation of m-xylene, and was observed at all tested conditions of temperature (15, 27, 35°C) and pH (5, 7, 9), showing in the range of 300 ~ 6100 RLU. Biokinetics of strain RB1401 in the presence of m-xylene were as follows: Y 0.56 mg/mg, μmax 2.67 day-1, and Ks 19.25 mg/L. A ratio of C:N(KNO3):P(KH2PO4) = 100:8:1.5 and 0.01% (w/v) of H2O2 were chosen for optimum biostimulation conditions of RB1401 with m-xylene in soil system. These results demonstrate the capability of such a genetically engineered bacteria for the development of biomonitoring and bioremediation in soil environments contaminated with specific volatile organic compounds. 相似文献
62.
P. VERBAARSCHOT D. CALVO G. D. ESSELINK J. Ma. MOLINA K. VRIELING P. W. DE JONG 《Molecular ecology resources》2007,7(1):60-62
Ten microsatellite markers for the flea beetle Phyllotreta nemorum were developed using di‐ and trinucleotide repeat‐enriched libraries. Each of these primer pairs were characterized on 96 individuals. Expected heterozygosities ranged between 0.11 and 0.84 and the number of alleles ranged between two and 14 per locus. These microsatellite markers are the first published for any Phyllotreta species. 相似文献
63.
B. J. A. POLLUX M. DE JONG A. STEEGH N. J. OUBORG J. M. VAN GROENENDAEL M. KLAASSEN 《Freshwater Biology》2006,51(11):2063-2071
1. The potential for seed dispersal by fish (ichthyochory) will vary among aquatic plants because of differences in seed size and morphology. 2. To examine how seed morphology influences the probability of dispersal by the common carp (Cyprinus carpio), we studied seed ingestion, retention time and subsequent egestion and germination of seeds of Sparganium emersum and Sagittaria sagittifolia, two aquatic plant species with similar sized but morphologically different seeds. 3. We compared dispersal probabilities between the two plant species, in which the probability of dispersal is assumed to be a function of the probabilities of seed ingestion, egestion and germination, and the dispersal distance is assumed to be a function of seed egestion rate over time. 4. We found that, although the soft seeds of S. sagittifolia had an approximately 1.5 times higher probability of being ingested by the carp than the hard seeds of S. emersum (83.15% ± 1.8% versus 56.16% ± 2.7%, respectively), the latter had an almost twofold higher probability of surviving the passage through the digestive tract (38.58% ± 2.7% versus 20.97% ± 1.5%, respectively). Patterns of seed egestion over time did not differ between the two plant species, despite the difference in seed morphology. Gut passage had a different effect on seed germination between plant species. Compared with non‐ingested controls, seeds of S. emersum showed a 12.6% increase in germination and a 2.1 day acceleration in germination rate, whereas seeds of S. sagittifolia displayed a 47.3% decrease and 5.1 day delay, respectively. 5. Our results suggest that seed morphology affects the dispersal probability and postdispersal establishment, but not the dispersal distance, of aquatic plants that are dispersed by fish. 相似文献
64.
From either a mycelial or a conidial inoculum the fungus survivedin soil as inactive chlamydospores. The level of its soil populationat equilibrium was too low to be studied by dilution plating.Plant materials placed on or beneath the surface of inoculatedsoil were colonized deeply by the fungus, which produced conidiaon them. Dispersal of conidia can occur with water movementin soil, and at right angles to, as well as in the directionof, that movement. No evidence was found of dispersal of thefungus in soil by continuous growth, even over continuous stretchesof organic matter. This finding was related to the inabilityof the fungus to colonize those organic materials that werepreviously colonized by other organisms from the soil, unlessits inoculum potential were greatly augmented. The fungus isthus seen to be a pioneer fungus. The strain used here grewoutwards a short distance from colonized organic food basesin the soil, leaving in the soil resting spores which couldcolonize fresh pieces of organic material subsequently addedthere. The organism could thus spread by discontinuous growthon successively available, fresh, organic materials. 相似文献
65.
66.
WILLARD Z. PARK 《American anthropologist》1938,40(4):622-638
67.
A cladistic analysis of the tribe Agathidiini Westwood is presented. Agathidiines are slime mould specialists and they are hypothesized to be a monophyletic group consisting of 12 genera (Afroagathidium Angelini & Peck, Agathidium Panzer, Anisotoma Panzer, Besuchetionella Angelini & Peck, Cyrtoplastus Reitter, Decuria Miller & Wheeler, Gelae Miller & Wheeler, Liodopria Reitter, Pseudoagathidium Angelini, Sphaeroliodes Portevin, and Stetholiodes Fall), based on three synapomorphies: epipleuron present to apical third, mesoventrite without longitudinal carina and longitudinal setal lines present on the tibiae. The dataset for phylogenetic analysis comprised 72 characters representing 198 character states derived from adult morphology. These data were analysed using equal weighting and implied weighting (k = 1–6) and supported the monophyly of the tribe based on three unique characters (epipleuron present to apical third, mesoventrite without longitudinal carina, longitudinal setal lines present on tibia) and two homoplastic characters [antennomeres 7–10 (or 6–9) asymmetrical, apical shape of terminal antennomere abruptly tapered]. The topology of IW trees with k = 4–6 was identical with one of three EW trees. Decuria was sister group to the remaining agathidiine genera whereas the following groups were resolved as monophyletic: Anisotoma, Gelae + Liodopria, and Pseudoagathidium (Afroagathidium + Besuchetionella). The clade [Sphaeroliodes rufescens (Agathidium bockshini, Agathidium subcostatum)] was supported in all analyses except for the IW (k = 1) cladogram. The monophyly of Agathidium was not supported at all and was rendered paraphyletic by the placements of Sphaeroliodes, Stetholiodes and the Pseudoagathidium (Afroagathidium + Besuchetionella) clade. Sphaeroliodes is synonymized with Agathidium ( syn.n. ) resulting in two new combinations [A. acuminatus (?vec) and A. rufescens (Portevin)]. Contractability is a complex character composed of several morphological features that have evolved independently within the agathidiine tree. Conglobation (the ability to roll the body into a ball) has arisen at least twice in Agathidiini. 相似文献
68.
Light-dependent potassium uptake by Pisum sativum leaf fragments 总被引:1,自引:0,他引:1
A net K+ influx into chopped pea leaves bathed in 5 mM KCl,0.26 M sucrose and illuminated with 4000 lux amounted to about7.5 µmoles/g fresh weight-hr, while essentially no netflux occurred in the dark. This light-dependent K+ uptake waslinear with time for nearly 2 hr and continuously increasedas the light intensity was raised to 9000 lux. Over half ofthe K+ uptake was balanced by H+ release into the bathing solution,possibly by a mechanism in which bicarbonate was the anion accompanyingK+. The replacement of Cl by HCO3 increased thelight-dependent K+ uptake to 56 µmoles/g fresh weight-hr.About 23% of the light-dependent K+ uptake in 5 mM KCl was accompaniedby a Cl uptake. This net Cl influx was less sensitiveto the uncoupler tri-Fl-CCP and more sensitive to DCMU in thebathing solution than was the K+ uptake. The remaining net K+influx into pea leaf fragments was balanced by effluxes of sodium(accounting for 5%), magnesium (8%) and calcium (1%). (Received March 31, 1969; ) 相似文献
69.
70.
Jong Kyun PARK Cheol Min LEE Tae Sung KWON Jin Young PARK Jong Eun LEE 《Entomological Research》2011,41(3):103-105
A truncatipennes‐group species, Coptodera japonica Bates, is newly recorded from Korea. Here we provide a diagnosis and systematic accounts of C. japonica Bates and a key to the species of Korean Coptodera. 相似文献