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1.
2.
Exobasidium symploci-japonicae var. carpogenum, causing Exobasidium fruit deformation on Symplocos lucida collected in Fukuoka Prefecture, Japan, is newly described based on morphological observations of hymenial structure and mode of basidiospore germination. This new variety differs morphologically from the type variety, particularly in the septal number of basidiospores and in the shapes and sizes of conidia formed on the medium. Colonies of this new variety are also distinguishable from those of the type variety by yeast-like growth, morphology, and color of colonies.Contribution no.178, Laboratory of Plant Parasitic Mycology, Institute of Agriculture and Forestry, University of Tsukuba, Japan  相似文献   

3.
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   

4.
The time to the most recent common ancestor of the extant populations of Plasmodium falciparum is controversial. The controversy primarily stems from the limited availability of sequences from Plasmodium reichenowi, a chimpanzee malaria parasite closely related to P. falciparum. Since the rate of nucleotide substitution differs in different loci and DNA regions, the estimation of genetic distance between P. falciparum and P. reichenowi should be performed using orthologous sequences that are evolving neutrally. Here, we obtained full-length sequences of two housekeeping genes, sarcoplasmic and endoplasmic reticulum Ca2+-ATPase (serca) and lactate dehydrogenase (ldh), from 11 isolates of P. falciparum and 1 isolate of P. reichenowi and estimate the interspecific genetic distance (divergence) between the two species and intraspecific genetic distance (polymorphism) within P. falciparum. Interspecific distance and intraspecific distance at synonymous sites of interspecies-conserved regions of serca and ldh were 0.0672±0.0088 and 0.0011±0.0007, respectively, using the Nei and Gojobori method. Based on the ratio of interspecific distance to intraspecific distance, the time to the most recent common ancestor of P. falciparum was estimated to be (8.30±5.40) × 104 and (11.62±7.56) × 104 years ago, assuming the divergence time of the two parasite species to be 5 and 7 million years ago, respectively.This article contains an online supplementary table.Reviewing Editor: Dr. Martin Kreitman  相似文献   

5.
The spatial genetic structure was assessed by amplified fragment length polymorphism (AFLP) technique for Quercus crispula Blume (37 individuals) and Q.dentata Thunberg (54 individuals) growing along a 550-m transect in Ishikari, Hokkaido, northern Japan. The simple Mantel test revealed significant negative correlation between genetic similarity and geographic distance in Q.dentata and negative but insignificant correlation in Q.crispula. Spatial autocorrelation analysis revealed that Mantels r generally decreased from positive to negative values with the increase of spatial distance in both oak species with significant deviation from zero for the 50–100-m (positive) and 250–300-m classes (negative) in Q.dentata. Thus, significant spatial genetic structure was revealed at least in Q.dentata  相似文献   

6.
 Two Exobasidium species causing Exobasidium leaf blister on Rhododendron spp. are described. An Exobasidium leaf blister on Rhododendron yedoense var. yedoense f. yedoense has been recognized in Hokkaido Prefecture, Japan, since the first report was issued in 1950. The causal fungus is identified with Exobasidium dubium from the morphology of its hymenial structure and mode of germination of the basidiospores. Another Exobasidium leaf blister on Rhododendron dauricum has been observed in Hokkaido Prefecture, Japan. In comparison with morphology based on hymenial structure and mode of germination of the basidiospores of the 100 validly described taxa, this fungus differs from those known taxa in the size of basidia and basidiospores, the numbers of sterigmata and septa of basidiospores, and the mode of germination of basidiospores. Thus, a new species, Exobasidium miyabei, is established and illustrated. Received: February 13, 2002 / Accepted: September 25, 2002  Present address: National Institute of Agrobiological Sciences, Tsukuba 305-8602, Japan Acknowledgments We profoundly appreciate the cooperation of Dr. V. Melnik in providing Russian papers and Dr. L. Vasilyeva for translating them into English. We thank Prof. H. Takahashi for loaning the materials in the Herbarium of the Hokkaido University Museum and Dr. W. Abe, Graduate School of Science, University of Hokkaido, for his kind help with the sampling of R. dauricum in Teshikaga, Hokkaido Prefecture. This study was supported in part by a Grant-in-Aid for Scientific Research (B) (No. 13460019), Japan Society for the Promotion of Science (JSPS). Contribution No. 171, Laboratory of Plant Parasitic Mycology, Institute of Agriculture and Forestry, University of Tsukuba. Correspondence to:M. Kakishima  相似文献   

7.
Of 98 strains of moulds, isolated from arctic soils, Mortierella minutissima 01, grew the best on agar plates with limonene vapor. Perillyl alcohol and perillic acid were the main products of limonene biotransformation. Maximal yield of perillyl alcohol (125mgl–1) occurred in medium containing 0.8% substrate, at 15°C, pH 6 and after 4–5 d. Revisions requested 27 October 2004; Revisions received 27 November 2004  相似文献   

8.
We investigated the carbon dynamics and budget in a grassland of Miscanthus sinensis, which is widely distributed in Japan, over a 2-year period (2000–2001). Plant biomass began to increase from May and peaked in September, then decreased towards the end of the growing season (October). Soil respiration rates also exhibited seasonal fluctuations that reflected seasonal changes in soil temperature and root respiration. The contribution of root respiration to total soil respiration was 22–41% in spring and summer, but increased to 52–53% in September. To determine the net ecosystem production (carbon budget), we estimated annual net primary production, soil respiration, and root respiration. Net primary production was 1207 and 1140gCm–2 in 2000 and 2001, respectively. Annual soil respiration was 1387gCm–2 in 2000 and 1408gCm–2 in 2001; root respiration was 649 and 695gCm–2 in 2000 and 2001, respectively. Moreover, some of the carbon fixed as net production (457–459gCm–2) is removed by mowing in autumn in this grassland. Therefore, the annual carbon budget was estimated to be –56gCm–2 in 2000 and – 100gCm–2 in 2001. These results suggest that the Miscanthus sinensis grassland in Japan can act as a source of CO2.  相似文献   

9.
Two new species of ricefishes or buntingi, Adrianichthys roseni and Oryzias nebulosus, are described from Lake Poso, Sulawesi Tengah, Indonesia, bringing to 12 the number of endemic ricefishes known from Sulawesi. Adrianichthys roseni and its sole congener, A. kruyti, are distinguished from other relatively large-bodied ricefishes, Xenopoecilus, in having orbits that project beyond the dorsal profile of the head; paired preethmoid cartilages (versus single or absent in Xenopoecilus); and 13–16 (versus 8–13) dorsal fin rays. Also, as in A. kruyti, the lower jaw of A. roseni is enclosed in the upper jaw when the mouth is closed; however, the upper jaw is not as large and broadly expanded as in A. kruyti. Adrianichthys roseni differs further from A. kruyti in having fewer scales in a lateral series (approximately 63–65 versus 70–75), attaining a smaller maximum recorded standard length (90mm versus 109mm), and having the lateral process of the pelvic bone in line with the fifth, rather than the eighth, pleural rib. Oryzias nebulosus shares with O. nigrimas, also from Lake Poso, a unique sexual dichromatism in preserved specimens: adult males are dark gray to black, whereas females are a lighter grayish-yellow to brown. Relative to O. nigrimas, O. nebulosus is a small species (maximum recorded SL 33mm versus 51mm), with pelvic fins relatively anterior (lateral process of pelvic bone is in line with the third, fourth, or fifth, modally fourth, rather than the fourth or fifth, modally fifth, pleural rib), dorsal fin relatively anterior (origin above the 12–14th anal fin ray as opposed to the 15–17th anal fin ray), precaudal vertebrae 11–13, modally 12 (versus 13–14, modally 13), and relatively straight, narrow and slender (as opposed to curved, broad, and robust) ossified and cartilaginous portions of the gill arches. Endemic buntingi are threatened by introduction of exotic species, overfishing, and pollution. A conservation plan includes rearing native fishes for local use as ornamental fishes and possible reintroduction.  相似文献   

10.
Caragana korshinskii Kom. is a very important shrub species for vegetation rehabilitation in northern China for its high ecological and economic values. Experiments were conducted to determine its germination responses to (i) different temperature regimes under light and/or dark conditions, (ii) different light intensities, and (iii) different water potentials combined with varied constant temperatures. Under alternating temperatures (from 5:15 to 25:35°C), final percent germinations of Caragana korshinskii were quite similar. In dark conditions, constant temperatures resulted in lower final percent germinations than alternating temperatures. At a controlled temperature regime of 10:20°C, neither final percent germinations nor germination rates showed significant differences among varied light intensities. As water potentials were reduced from 0 (distilled water) to –0.6MPa, final percent germinations increased slightly and reached the peak at approximately –0.6MPa, however, the increment was not significant. Beyond –0.6MPa, further water potential reduction led to decreased final percent germinations and few seeds could germinate at –1.4MPa. Water stress also strongly inhibited germination at very high or low temperatures. The experimental results suggested that middle May might be a suitable time for aerial seeding for this species.  相似文献   

11.
Competition in a natural system may be interspecific or intraspecific. In semiarid ecosystems, competition for resources between established neighboring grass species and newly recruited seedlings is very high. To examine the effects of grass species density, growing space and time of establishment on Eucalyptus victrix seedlings (interspecific competition), and the effect of density and growing space within E.victrix (intraspecific competition) we conducted an experiment under controlled conditions. We tested four hypotheses (i) E.victrix seedling growth is not affected by grass density; (ii) there is no difference in E.victrix survival and growth between early and later grass establishment; (iii) interspecific competition is not more intense than intraspecific competition in E.victrix; and (iv) growth of E.victrix seedlings is not dependent on available growing space. In a monoculture of E.victrix, seedling mortality was higher (10%) in large pots. In mixed culture pots, where E.victrix seedlings and grass seedlings were planted on the same day, E.victrix seedlings survived for up to 4weeks, but started to die after week five in the smallest pots. However, mortalities occurred in pots of all sizes when grass was established before E.victrix seedlings. Results also indicated that the resources necessary for the growth of individual E.victrix seedlings were more limiting under conditions of increased density of neighboring grass species rather than intraspecific competition. In particular, photosynthetic area of E.victrix seedlings was drastically reduced in mixed cultures. Although density, pot size and time of planting had impacts on E.victrix seedlings, the patterns of these impacts were variable.  相似文献   

12.
The chromosomes of eight species of Rutilus and Scardinius, mostly endemic to the Italian and the Balkan peninsula, were analyzed by conventional and other banding techniques. Parallel analyses were conducted also on two leuciscine species, Alburnus albidus, for which we provide the first karyological analysis, and Leuciscus cephalus. All species examined displayed the same karyotype (2n=50 chromosomes, 8 metacentric+13 submetacentric+4 subtelo/acrocentric pairs) with nucleolus organizer regions (NORs) on the ends of the shorter arms of a medium-sized submetacentric pair. In contrast, interspecific variation was observed in the distribution of constitutive heterochromatin. The variation observed in this genomic material proved to be systematically and phylogenetically informative. Indeed, a peritelomeric C-band on the first telocentric pair characterizes species of Rutilus and Scardinius. In both genera heterochromatin differentiation appears to be directed to a centromere–telomere direction, particularly evident along the metacentric elements of their karyotypes.An erratum to this article can be found at  相似文献   

13.
Eleven postflexion larvae (9.1–23.9mm standard length: SL) of a bothid, Arnoglossus elongatus, from northwestern Australian waters were described. These specimens were characterized by vertebral numbers of 11–12+32–34=43–45, slender body, remarkably elongated second dorsal fin ray, and presence of melanophores on and slightly above midlateral line of body, plus on dorsal wall of abdominal cavity and air bladder (specimens >12.6mm SL), proximally on caudal fin rays (>16.5mm SL), and on pterygiophore zones of dorsal fin and anal fin (>23.8mm SL).  相似文献   

14.
Seasonal changes in microcystin concentrations in a resident snail (Sinotaia histrica) and an edible clam (Corbicula sandai) in Lake Biwa were surveyed. To clarify both the accumulation and depuration of microcystins, experimental studies with microcystin were also carried out on the snail. In the field investigation, microcystin was detected from the hepatopancreas and intestine of S. histrica (up to 3.2µgg–1 dry weight and 19.5µgg–1 dry weight, respectively); however, no microcystin was detected in the hepatopancreas of C. sandai. In the laboratory experiment, the microcystin-LR concentration in the hepatopancreas of S. histrica reached a value of 436µgg–1 dry weight on day 10 of 15 days of uptake, and a high value persisted despite a depuration period of 15 days. The depuration rate constant of microcystin and its biological half-life were 0.0828 day–1 and 8.4 days, respectively. These results indicate that S. histrica has a high ability to accumulate microcystin in its tissue. Because S. histrica is predated by fish and water fowl, it is likely to play an important role as a vector for microcystin in lakes with dense blooms of toxic cyanobacteria.  相似文献   

15.
Suillus and Boletinus were studied using Ohta medium. In media with glucose or trehalose, all tested strains grew well. With mannose and cellobiose, strains generally grew well, except for one strain of Suillus. Utilization of dextrin and soluble starch differed with each strain, and that of sucrose and glycerol was low for all strains. Utilization of four amino acids, arginine, glutamic acid, aspartic acid, and alanine, was similar to that of ammonium tartrate for Suillus strains, but mycelial growth with amino acids was clearly lower than with ammonium tartrate for the Boletinus strain. The effect of glucose and ammonium tartrate concentrations for nine strains of the genera Suillus and Boletinus was studied with ranges for glucose of 1–100 and 200g/l, respectively, and for ammonium tartrate of 0.2–5 and 20g/l, respectively. Six strains showed maximal growth at a glucose concentration greater than 25g/l, and one strain showed maximal growth at 70g/l. The results indicate that these fungi are adapted to relatively high concentrations of carbon sources. In general, glucose concentration at mycelial growth maximum decreased as ammonium tartrate concentration increased, and at higher concentrations of glucose, mycelial growth decreased more rapidly in higher concentrations of ammonium tartrate.  相似文献   

16.
A new genus and species of zoarcid fish, Magadania skopetsi, is described on the basis of 17 specimens (83.4–115.9mm SL) from the intertidal zone of the northern coast of the Sea of Okhotsk, near Magadan, Russia. This species differs from other known zoarcid genera and species by having the following combination of characters: suborbital bones 5, the suborbital canal with 6–8 small pores; first epibranchial fan-shaped; palatopterygoid series reduced; supraoccipital broadly contacting exoccipital; posttemporal ventral ramus weak; upper lip continuous at symphysis; palatine teeth, pelvic fins and scales present; lateral line configuration mediolateral, incomplete, absent on posterior half of body; vertebrae 18–22+78–83=97–104. The closest genus cannot be determined cladistically except that the species is a member of the subfamily Gymnelinae. During the spawning season, M. skopetsi lives under stones near the outer marginal area of the intertidal zone.  相似文献   

17.
Immobilization of Chlamydomonas reinhardtii in alginate increases its photorespiration rate. In the immobilized cells, the photorespiratory enzyme, phosphoglycolate phosphatase, was 75% higher than in freely suspended cells. Thus, the immobilized cells produced glycolate at twice the rate than in freely suspended cells when treated with aminooxyacetate (a transaminase inhibitor). With immobilized cells in a batch reactor, 270mol glycolatemg–1 Chl was produced after 12h.Revisions requested 27 October 2004; Revisions received 13 December 2004  相似文献   

18.
The eddy correlation technique was employed to measure net ecosystem carbon dioxide (CO2) (NEE) and water vapor exchange (LE) over a C3/C4 co-occurring wet temperate Miscanthus-type grassland in the Kanto plain of Japan in the 1999 growing season. The maximal mean canopy height and maximal leaf area index were 1.0m and 5.5, respectively. The daily maximal LE was approximately 540Wm–2. The maximum value of daily accumulative LE was 16.3MJday–1. Daily variation of the decoupling factor () suggests that in the morning LE decoupled with the atmosphere, and the available energy was the major driving force for LE, whereas in the afternoon LE coupled strongly with the atmosphere, and the atmospheric evaporative demand played a critical role in LE. The decline in (from 0.8 to 0.5) with the growing season demonstrates that LE decoupled from the atmosphere in the later growth season. The peak NEE value was 57.4µmolCO2m–2s–1 (the positive value signifies the canopy carbon gain was from the air). The maximal daily integrated NEE was 1.06molCO2m–2day–1 observed during the peak growth stage. A rectangular hyperbolic model was used to describe the relation between daytime NEE and incident photosynthetic photon flux density (PPFD). The net ecosystem CO2 was not light-saturated up to a PPFD level of 2000µmol m–2s–1. The initial slope estimated with the NEE–PPFD response model was approximately 0.042molCO2mol–1photon on average. The canopy light compensation point ranged from 210 to 430µmolm–2s–1 with an average of approximately 310µmolm–2s–1. Both the initial slope and the canopy light compensation point decreased as the canopy senesced. The switch in dominance from C3 to C4 plants played an important role in the canopy fluxes.  相似文献   

19.
The effects of fertilization [control (C), 200kgNha–1+25kgP ha–1 (LNP) and 400kgNha–1+ 50kgP ha–1 (HNP)] on fine root dynamics were examined in a 40-year-old Larix leptolepis plantation in central Korea. The average fine root biomass during the growing season for C, LNP and HNP was 957, 934 and 814kgha–1, respectively, whereas the fine root production for C, LNP and HNP was 2103, 2131 and 2066kgha–1, respectively. Nitrogen and P inputs into the soil via fine root turnover for C, LNP and HNP were 23.0 and 1.2, 23.3 and 1.2 and 22.6 and 1.2kgha–1, respectively. There were no significant differences in fine root biomass, production and N and P inputs through fine root turnover between the fertilization treatments during the first growing season after fertilization.  相似文献   

20.
Tissue-cultured plantlets of three sugarcane (Saccharum spp.) cultivars having a known field smut reaction were screened for susceptibility to Ustilago scitaminea H&P Sydow. Plantlets were inoculated with 0.5 l of a suspension of equally mixed quantities of plus and minus mating type sporidia of U. scitaminea at concentrations ranging from 1×101 to 1×106 cells. Fungal sori (whips) were produced in cultivar N12 (intermediate) 6weeks following inoculation with 1×105 mixed sporidia and thereafter in cultivar NCo310 (susceptible) but not in cultivar N19 (resistant). Sori bearing teliospores were produced up to 3months following inoculation and incubation at 26°C. No sori were produced at mixed sporidial concentrations lower than 1×105cells. The in vitro soral production in cultivars N19, N12 and NCo310 was 0, 27.5 and 47.5% respectively. Plantlets inoculated with 1×105sporidia of only one mating-type did not produce sori in any of the three cultivars tested. Blind scoring of an unknown sugarcane cultivar by this method corresponded exactly with its field smut rating.  相似文献   

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