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41.
Illumination of pea plants caused a doubling in the rate ofCO2 fixation by the subsequently isolated chloroplasts comparedwith the rate obtained for chloroplasts from plants in the dark.This enhancement in the CO2 fixation rate was half-maximal for800 lux incident on the plants and was 90% light saturated at2000 lux. The half-time for the enhancement of the CO2 fixationrate following illumination of the plants was about 4 min andthe half-time for its reversal when the plants were placed backin the dark was 5 min. Illuminating the plants had relativelylittle effect on the O2 evolution rate of the subsequently isolatedchloroplasts. Moreover, the ferricyanide reduction rate by theisolated chloroplasts was also essentially unaffected by theillumination condition of the plants from which the chloroplastswere isolated. Consequently, light on the plant apparently causesa doubling in the CO2 fixed per electron moving in the photosyntheticelectron transport pathway. This enhanced coupling is discussedin terms of a concomitant increase in endogenous photophosphorylationand flattening of the chloroplasts in vivo, other changes causedby light incident on the plant. (Received January 16, 1970; ) 相似文献
42.
We developed 11 new microsatellite markers in Pseudosciaena crocea by screening an enriched genomic library using nonradioactive polymerase chain reaction (PCR) techniques. All loci were found to be polymorphic with an average of 14.9 alleles per locus (range four to 30). The mean observed and expected heterozygosities were 0.86 (range 0.57–1.00) and 0.90 (range 0.62–0.98), respectively. Four loci showed significant Hardy–Weinberg disequilibrium. The high variabilities revealed in this study suggest that these microsatellite loci should provide useful markers for population genetic studies of P. crocea. 相似文献
43.
BYUNG CHEOL CHO JONG SOO PARK KUIDONG XU JOONG KI CHOI 《The Journal of eukaryotic microbiology》2008,55(5):417-426
ABSTRACT. A new ciliate, Trimyema koreanum n. sp., isolated from hypersaline water (salinity of 293‰) from a solar saltern in Korea, was investigated using live observation, protargol impregnation, and gene sequencing. Trimyema koreanum is about 30 × 13 μm in vivo, has usually 23 longitudinal ciliary rows forming two distinct ciliary girdles visible both in vivo and in protargol impregnation. A third indistinct ciliary girdle as well as a girdle of mucocysts is distinguishable only in impregnated cells. We suggest T. koreanum as a new species, differing from the most similar species, T. marinum, by the presence of two distinct ciliary girdles (T. marinum usually has six ciliary girdles clearly visible in living cells and three anterior spirals that encircle the cell completely). Although the number of known 18S rRNA sequences in the genus Trimyema was limited, the Trimyema group including T. koreanum forms a strong clade. The phylogenetic position confirms that the isolate belongs to the genus Trimyema and is different from previously sequenced species. Trimyema koreanum is able to consume both prokaryotes and small eukaryotes (specifically, the alga Dunaliella sp.). 相似文献
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Kyung-Hwa PARK 《Entomological Research》2009,39(5):334-340
In order to elucidate the phylogenetic relationship among groups of the order Entomobryomorpha (Collembola), the sequences on the ITS 1 to ITS 2 fragments of the rRNA gene were analyzed in 11 species of three families. In order to avoid the potential risks and inconsistencies of a single method or data set, the phylogenetic reconstructions were based on three different approaches: methods of maximum parsimony, maximum likelihood and neighbor joining. The inferred phylogenies supported monophyly of the order Entomobryomorpha. The relationships between families were different, but the orders of branching within each family were the same. Entomobryidae and Isotomidae were paraphyletic, whereas Tomoceridae was monophyletic. Tomoceridae was subdivided into two branches; the molecular analysis provided results distinctive enough to separate the two genera by the high bootstrap value. On the other hand, two different populations of putative Homidia koreana appeared to be different species, although their chaetotaxy is identical. A wide coverage of characters, including not only morphological characters but also genetic data such as allozymes and DNA sequences, will give a more accurate picture of the classification and phylogeny of the studied group. 相似文献
46.
The genus Scaphobaeocera Csiki including three species ( S. dorsalis Löbl, S. inexpectata Löbl, S. pecki Löbl) is identified for the first time in Korea. A key to the species is given with diagnosis and illustrations of important morphological features. 相似文献
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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
49.
1. Bumblebee nests are difficult to find in sufficient numbers for well replicated studies. Counts of nest‐searching queens in spring and early summer have been used as an indication of preferred nesting habitat, but this relationship has not yet been validated; high densities of nest‐searching queens may indicate habitat with few nesting opportunities (meaning that queens have to spend longer looking for them). 2. From mid April 2010, queen bumblebees were counted along 20 transects in grassland and woodland habitats in central Scotland, U.K. The number of inflorescences of suitable forage plants were also estimated at each transect visit. The area surrounding each transect was searched for nests in the summer. 3. In total, 173 queen bumblebees were recorded on transects, and, of these, 149 were engaged in nest‐searching. Searches subsequently revealed 33 bumblebee nests. 4. The number of nest‐searching queens on transects was significantly, positively related to the number of nests subsequently found. Estimated floral abundance along the transect did not correlate with numbers of nest‐searching queens or with the number of nests found, suggesting that queens do not target their searching to areas that are locally high in spring forage. 5. The data suggest that counts of nest‐searching queens provide a useful positive indication of good nesting habitat, and hence where bumblebee nests are likely to be found later in the year. 相似文献
50.
Kyu‐Tek PARK 《Entomological Science》2012,15(3):294-302
As the eighth part in a series on the family Lecithoceridae (Lepidoptera: Gelechioidea) from New Guinea, Sulciolus Park, gen. nov. of the subfamily Lecithocerinae is described, based on the type species, S. pachystoma (Diakonoff), comb. nov., with two additional new species: (i) S. circulivalvae sp. nov.; and (ii) S. kaindiana sp. nov. The new genus shares with Achroa Meyrick, Onnuria Park, Hamatina Park and Scolizona Park a uniquely specialized 3rd segment of labial palpus, but it is differentiated from them by having a longitudinal furrow on the inner surface of the segment. Sulciolus abrasa (Diakonoff), S. capra (Diakonoff), S. induta (Diakonoff) and S. perspicua (Diakonoff) are newly combined, and Lecithocera sextacta Diakonoff is synonymized with S. perspicua (Diakonoff). Keys to genera related to Lecithocera and to species of the genus are given. Adults, labial palpi, wing venations and male genitalia are illustrated. 相似文献