共查询到20条相似文献,搜索用时 31 毫秒
1.
This work evaluated the breeding success of Bubulcus ibis (Ardeidae), Egretta thula, Nycticorax nycticorax, Phimosus infuscatus and Plegadis chihi in Rio Grande do Sul during two consecutive nesting seasons. Mean clutch size for B. ibis was 2.59 in 1998/1999 and 2.49 in 1999/2000. The species with both the smallest and largest clutch was P. infuscatus, with 2.04 in 1999/2000, and 3.16 in 1998/1999. The highest mean number of nestlings per nest was 2.86 for P. chihi in 1998/1999 and the lowest was 1.85 for B. ibis in 1998/1999 and P. infuscatus in 1999/2000. In both nesting seasons all the species had major success, laying three eggs and raising two nestlings, exept for B. ibis. The breeding success for P. chihi varied from 1.54 young/nest in 1998/1999 to 0.4 in 1999/2000, whereas B. ibis ranged from 1.16 in the first period to 0.99 in the second. 相似文献
2.
T. Karanovic 《Helgoland Marine Research》2000,54(1):33-38
A new species of Arenopontia (Neoleptastacus) is described on the basis of a single female collected from one sandy beach in Montenegro, Adriatic Sea. With the addition
of the new species, the subgenus Neoleptastacus now includes 18 species throughout the world. At the end of this paper there is a key for their determination.
Received: 20 March 1999 / Received in revised form: 15 September 1999 / Accepted: 21 September 1999 相似文献
3.
Indirect effects mediated by compensatory shoot growth on subsequent generations of a willow spittlebug 总被引:1,自引:1,他引:0
We investigated whether oviposition by the spittlebug Aphrophora pectoralis on Salix miyabeana and S. sachalinensis in fall 1998 affected shoot growth pattern and further oviposition by subsequent generations of the willow spittlebug in
early September 1999 and 2000. Spittlebug oviposition enhanced the growth of current-year shoots on 1-year shoots with oviposition
(O-shoots) compared to those without oviposition (N-shoots): the length of current-year shoots increased in 1999 and 2000,
the number of current-year shoots increased in 2000 despite a decrease in 1999, and the shoot abscission rate decreased during
the 1999 winter. The number of egg masses per current-year shoot was greater on O-shoots than on N-shoots in 1999, and this
tendency was reinforced in 2000. The total number of egg masses was greater on O-shoots than on N-shoots in 2000, although
there was no significant difference in 1999. There is thus a positive feedback system between spittlebug attack and compensatory
growth on willow.
Received: April 11, 2002 / Accepted: July 30, 2002
Present address: Center for Ecological Research, Kyoto University, Otsu, Japan
Acknowledgments We thank Masanori J. Toda and Andrew Davis for valuable comments and critical reading on this paper. Financial support was
provided by a Japanese Ministry of Education, Science, Sports, and Culture Grant-in-Aid for Creative Basic Research to Takayuki
Ohgushi.
Correspondence to:A. Nozawa 相似文献
4.
Endophytic fungi in leaves of Lycopersicon esculentum Mill 总被引:1,自引:0,他引:1
Endophytic fungi were isolated from healthy tomato leaves from field-grown plants. Several surface-sterilization techniques were assayed for removing and killing epiphytes on tomato leaves. Surface-sterilization with an undiluted commercial solution of sodium hypochlorite was employed. To determine the spectrum of endophytes, samples were collected in February 1998 and 1999 from tomato plants (cultivar Tommy) cultivated in the experimental fields of Facultad de Ciencias Agrarias y Forestales, Universidad Nacional de La Plata, Buenos Aires, Argentina. In general, different spectra of species were isolated in 1998 and 1999.Alternaria alternata was the fungus most frequently isolated from tomato leaves in 1999, but it was the second most common species in 1998. In contrast, Colletotrichum gloeosporioides was the fungus most frequently isolated in 1998, but it was not found in 1999. Species of other genera, such as Cladosporium and Penicillium, were isolated in both years. 相似文献
5.
G. A. Akpan 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(2):315-318
Cytogenetic characteristics confirm that Hibiscus acetosella and Hibiscus cannabinus are outbreeders, while Hibiscus asper, Hibiscus physaloides, Hibiscus sabdariffa and Hibiscus surattensis have evolved into inbreeders. The inbreeding species appear to have co-evolved a floral structure in which some anthers abut
on the stigma prior to anthesis.
Received: 19 February 1999 / Accepted: 17 June 1999 相似文献
6.
K. Rajasekaran J. W. Cary T.J. Jacks K. D. Stromberg T.E. Cleveland 《Plant cell reports》2000,19(4):333-338
Transgenic tobacco plants producing chloroperoxidase (CPO-P), encoded by a novel gene from Pseudomonas pyrrocinia, were obtained by Agrobacterium-mediated transformation. Successful transformation was shown by PCR, Southern, northern and western blot analyses, and assays
of CPO-P enzyme activity. Extracts from plants transformed with the CPO-P gene significantly reduced Aspergillus flavus colonies by up to 100% compared with extracts from control plants transformed with pBI121. Compared with controls, the transformed
plants showed increased disease resistance in planta against a fungal pathogen, Colletotrichum destructivum, the causal agent of tobacco anthracnose.
Received: 10 March 1999 / Revision received: 22 June 1999 · Accepted: 5 July 1999 相似文献
7.
Ligninolytic basidiomycetes were screened for their ability to reduce aryl acids to the corresponding aldehydes and alcohols.
Seven fungal strains converted p-anisic acid in high molar yields to the reduced products. The white-rot fungus Bjerkandera sp. strain BOS55 was one of the best reducing strains and was highly tolerant towards high concentrations of different aromatic acids. It
was tested for the reduction of p-anisic, veratric, 3-chloro-4-methoxybenzoic, 3,5-dichloro-4-methoxybenzoic, 3,4-dichlorobenzoic, 4-fluorobenzoic, and 3-nitrobenzoic
acids. All of these compounds were reduced to their corresponding aldehydes and alcohols.
Received: 22 March 1999 / Received revision: 12 July 1999 / Accepted: 1 August 1999 相似文献
8.
Embryogenic tissue of Pinus patula Scheide et Deppe was cryopreserved for 8 weeks using sorbitol and dimethylsulfoxide (DMSO) as cryoprotectants. Results indicate
that 0.3 M sorbitol and 5% DMSO had the best cryoprotecting effect. The recovered tissue initially underwent a lag phase but then continued
to proliferate normally on MSG3 maintenance medium. Recovered tissue was placed onto MSG5 maturation medium, and embryos were
isolated and germinated. Plantlet regeneration from the recovered tissue was achieved.
Received: 16 April 1999 / Revision received: 26 July 1999 / Accepted: 17 August 1999 相似文献
9.
M. Emmerson 《Helgoland Marine Research》2000,54(2-3):110-116
Increasing concerns over global warming and expected sea level rises have led to the adoption of new coastal management strategies
around the south-east coast of England. This paper explores the role played by the estuarine invertebrate Nereis diversicolor in limiting the colonisation and establishment of the invasive pioneering salt marsh plant, Spartina anglica. The biology of N. diversicolor is briefly reviewed and data from field experiments are presented demonstrating significant negative effects of worm abundance
on transplanted S. anglica biomass. Laboratory-based experiments demonstrated significant negative effects of N. diversicolor abundance on the survival of S. anglica seeds transplanted to sediment cores. The importance of estuarine invertebrates in engineering the mudflat habitat may confound
the foreseen ecosystem services and function provided by saltmarsh management schemes.
Received: 15 February 1999 / Received in revised form: 4 June 1999 / Accepted: 11 June 1999 相似文献
10.
Parshikov IA Freeman JP Williams AJ Moody JD Sutherland JB 《Applied microbiology and biotechnology》1999,52(4):553-557
Cultures of the fungi Aspergillus niger, Cunninghamella verticillata, and Penicillium simplicissimum, grown in a sucrose/peptone medium, transformed N-acetylphenothiazine to N-acetylphenothiazine sulfoxide (from 13% to 28% of the total) and phenothiazine sulfoxide (from 5% to 27%). Phenothiazin-3-one
(4%) and phenothiazine N-glucoside (4%) were also produced by C. verticillata. The probable intermediate, phenothiazine, was detected only in cultures of P. simplicissimum (6%).
Received: 15 January 1999 / Received revision: 7 May 1999 / Accepted: 21 May 1999 相似文献
11.
Transgenic plants of cassava (Manihot esculenta) with resistance to Basta obtained by Agrobacterium-mediated transformation 总被引:1,自引:0,他引:1
Transgenic plants of cassava (Manihot esculenta) resistant to the herbicide Basta were obtained through Agrobacterium-mediated transformation. The plants also expressed the uidA gene and two were positive for PCR- and/or Southern-based detection of the nptII gene. Somatic-embryo-derived cotyledons were used as source of explants. A non-disarmed Agrobacterium strain (CIAT 1182) was used to transfer the genes of interest into cassava cultivar MPer183. Greenhouse tests of resistance
to Basta (Hoechst) showed three plant lines with different levels of tolerance to the herbicide. Based on Southern tests of
transgenesis, the transformation efficiency was 1%. The results constitute the first report of the bar gene conferring herbicide resistance to cassava plants.
Received: 9 January 1999 / Revision received: 10 May 1999 / Accepted: 15 June 1999 相似文献
12.
H. Fukuoka T. Ogawa I. Mitsuhara T. Iwai K. Isuzugawa Yoko Nishizawa Y. Gotoh Yaeko Nishizawa A. Tagiri M. Ugaki M. Ohshima H. Yano N. Murai Y. Niwa T. Hibi Y. Ohashi 《Plant cell reports》2000,19(8):815-820
The NCR promoter (PNCR) from soybean chlorotic mottle virus (SoyCMV) was used to express the selectable marker, neomycin
phosphotransferase (nptII) gene, in Agrobacterium-mediated transformation of both monocot (rice) and dicot (tobacco) plants. A multi-cloning site for insertion of a gene of
interest into the binary vector pTN is located proximal to the right border region of T-DNA. When chimeric genes under the
control of other strong promoters were located in a head-to-head orientation to the PNCR-nptII gene, kanamycin-resistant tobacco shoots were generated more efficiently than when using the original pTN vectors. This suggests
that the enhancer-like sequences in the promoters adjacent to PNCR may promote expression of the PNCR-nptII gene.
Received: 20 August 1999 / Revision received: 16 November 1999 / Accepted: 19 November 1999 相似文献
13.
Different spore types are abundant in the atmosphere depending on the weather conditions. Ascospores generally follow precipitation,
while spore types such as Alternaria and Cladosporium are abundant in dry conditions. This project attempted to correlate fungal spore concentrations with meteorological data
from Tulsa, Oklahoma during May 1998 and May 1999. Air samples were collected and analyzed by the 12-traverse method. The
spore types included were Cladosporium, Alternaria, Epicoccum, Curvularia, Pithomyces, Drechslera, smut spores, ascospores, basidiospores, and other spores. Weather variables included precipitation levels, temperature,
dew point, air pressure, wind speed, wind direction and wind gusts. There were over 242.57 mm of rainfall in May 1999 and
only 64.01 mm in May 1998. The most abundant spore types during May 1998 and May 1999 were Cladosporium, ascospores, and basidiospores. Results showed that there were significant differences in the dry-air spora between May 1998
and May 1999. There were twice as many Cladosporium in May 1998 as in May 1999; both ascospores and basidiospores showed little change. Multiple regression analysis was used
to determine which meteorological variables influenced spore concentrations. Results showed that there was no single model
for all spore types. Different combinations of factors were predictors of concentration for the various fungi examined; however,
temperature and dew point seemed to be the most important meteorological factors.
Received: 5 July 2000 / Revised: 20 December 2000 / Accepted: 22 December 2000 相似文献
14.
The use of phosphomannose-isomerase as a selectable marker to recover transgenic maize plants (Zea mays L.) via Agrobacterium transformation 总被引:5,自引:0,他引:5
A new selectable marker system has been adapted for use in Agrobacterium-mediated transformation of maize. This selection system utilizes the pmi gene encoding for phosphomannose-isomerase that converts mannose-6-phosphate to fructose-6-phosphate. Only transformed cells
are capable of utilizing mannose as a carbon source. Agrobacterium-mediated transformation of immature embryos followed by a pre-selection of 10–14 days prior to selection at a level of 1%
mannose and 0.5% sucrose led to the recovery of trangenic lines of a frequency of as high as 30% in about 12 weeks. Molecular
and genetic analysis showed that selected plants contained the pmi gene and that the gene was transmitted to the progeny in a Mendelian fashion.
Received: 24 August 1999 / Revision received: 27 September 1999 / Accepted: 9 November 1999 相似文献
15.
K. Kamaté I. D. Rodriguez-Llorente M. Scholte P. Durand P. Ratet E. Kondorosi A. Kondorosi T. H. Trinh 《Plant cell reports》2000,19(7):647-653
A high frequency of embryogenesis and transformation from all parts of flowers of two lines of Medicago truncatula R-108–1 and Jemalong J5 were obtained. Using this flower system, we obtained transgenic plants expressing promoter-uidA gene fusions as well as the gfp living cell color reporter gene. Moreover, this method allows us to save time and to use a smaller greenhouse surface for
the culture of donor plants. Southern hybridization showed that the internal gfp fragment had the expected size and the number of T-DNA copies integrated in the plant genome varied between one and three.
These data suggest that the presence of the GFP protein has no toxic effects, since no rearrangement of the gfp reporter gene was detected in the regenerated plants.
Received: 25 May 1999 / Revision received: 2 August 1999 / Accepted: 2 August 1999 相似文献
16.
Methyl ent-17-hydroxy-16β-kauran-19-oate was fed to a 2-day-old culture of the fungus Rhizopus stolonifer, fermenting at room temperature (25 °C) in an orbital shaker (2 l). After 11 days, both broth and mycelia were extracted
with ethyl acetate. Two novel compounds were isolated from this experiment: methyl ent-9α,17-dihydroxy-16β-kauran-19-oate and methyl ent-7α,17-dihydroxy-16β-kauran-19-oate. Their structures were fully confirmed by spectroscopic methods.
Received: 22 July 1999 / Received revision: 2 November 1999 / Accepted: 12 November 1999 相似文献
17.
Onuma Y Nishihara R Takahashi S Tanegashima K Fukui A Asashima M 《Development genes and evolution》2000,210(6):325-327
The Ran gene family encodes small GTP binding proteins that are associated with a variety of nuclear processes. We isolated a Xenopus Ran cDNA and analyzed the pattern of expression of this gene during embryogenesis. Ran is expressed maternally and later in the CNS, neural crest, mesenchyme, eyes, and otic vesicles. However, expression is not
detected in the somites or the notochord.
Received: 22 November 1999 / Accepted: 22 December 1999 相似文献
18.
A Saccharomyces cerevisiae mutant affected in the last step of the biotin biosynthesis pathway was isolated by using a transposon mutagenesis method.
The gene BIO2, encoding a biotin synthase, is shown to be interrupted in this mutant. Heterologous complementation experiment allowed the
cloning and the characterization of a novel bio gene: bio2, encoding biotin synthase from Schizosaccharomyces pombe.
Received: 4 June 1999 / Accepted: 12 July 1999 相似文献
19.
Transgenic oat plants via visual selection of cells expressing green fluorescent protein 总被引:11,自引:0,他引:11
H. F. Kaeppler G. K. Menon R. W. Skadsen A. M. Nuutila A. R. Carlson 《Plant cell reports》2000,19(7):661-666
New selectable markers and selection systems are needed to increase the efficiency and flexibility of plant transformation.
The objective of this research was to determine if the green fluorescent protein (gfp) gene could be utilized as a visual selectable marker for transformation of oat (Avena sativa L.). A modified gfp gene was delivered into oat cells by microprojectile bombardment. Cell clusters expressing gfp were visually identified using fluorescence microscopy and physically isolated at each subculture. Eleven independent transgenic
cell lines were obtained, and fertile plants regenerated from all lines. Transgene integration and expression were confirmed
in transgenic plants and progeny. Transgene expression segregated in a 3 : 1 ratio in progeny of the majority of the transgenic
lines.
Received: 11 May 1999 / Revision received: 31 August 1999 / Accepted: 2 September 1999 相似文献
20.
Local therapy with interleukin-2 (IL-2) and other cytokines may be a very effective way to treat cancer. This was the theme
of the First Symposium on Local Cytokine Therapy of Cancer: Interleukin-2, Interferons and Related Cytokines, in Hamburg,
29 April–1 May 1999. The abstracts are published in Anticancer Research 19: 1995–2016 (1999) [1]. Here we present a report.
Received: 28 October 1999 / Accepted: 2 December 1999 相似文献