太谷核不育和T型不育小麦的发育解剖学特征

对回交转育的太谷核不育小麦的可育株、不育株、T型不育小麦植株及回交亲本植株的茎、叶、叶鞘的解剖学特征进行了比较研究.通过对数量化的解剖结构特征的单一自由度方差分析表明.茎、叶、叶鞘组织和维管束在发育过程中受到了不育基因的影响.初步证明不育基因不仅影响小麦生殖器官的发育,并引起败育.而且也影响营养器官的发育.     

The commercial exploitation of a protected anadromous species,the river lamprey (Lampetra fluviatilis (L.)), in the tidal River Ouse,north‐east England

• 1. Throughout Europe, populations of anadromous fish and lampreys have declined over the past centuries due to human activities. River lamprey Lampetra fluviatilis are representative of such species and are listed in international conservation agreements.
• 2. Historic (1908–09 to 1913–14) and modern (1995–96 to 2003–04) data were available on commercial catches of river lampreys in the tidal Ouse, north‐east England. During 2003–04, additional traps were operated by the University of Durham, downstream of the commercial fishery.
• 3. Catch per unit effort (CPUE) in the modern commercial fishery showed considerable variation between fishing seasons, ranging from a median CPUE of 0.5 lampreys per trap per day in 2000–01 to a median of 22.3 lampreys per trap per day in 2003–04.
• 4. The estimated catch of adult river lampreys each season in the historic fishery ranged between 25 500 (1913–14) and 54 500 (1910–11). Recent catches tended to be smaller, with a minimum catch of 9083 lampreys (2000–01) and a maximum of 30 992 lampreys (2003–04).
• 5. CPUE increased with discharge, up to a point above which CPUE declined with further increase in discharge. Migratory activity may be reduced at high flows and not stimulated at low flows, although the fishing efficiency of the traps themselves was probably reduced during high flows.
• 6. Samples of river lampreys caught in the university's traps were marked and released. Based upon the number of recaptures, the absolute minimum relative exploitation level of the commercial traps, over the whole fishing season, was estimated as 9.9%. The effect of such a reduction in the spawning population upon future recruitment is at present unknown.
• 7. The population of river lampreys in the tidal Ouse is potentially threatened by an unregulated increase in fishing effort. Current legislation needs to be modified to allow effective fishery management.

Copyright © 2006 John Wiley & Sons, Ltd.     

Pathogenicity of H5N1 influenza A viruses isolated in Vietnam between late 2003 and 2005

Since late 2003, highly pathogenic H5N1 influenza A viruses have spread among poultry and wild aquatic birds in Asian countries. Transmission of these viruses to humans can be lethal. Most human cases of infection with H5N1 viruses have occurred in Vietnam. Therefore, to understand the pathogenicity in mammals of these H5N1 viruses, we took viruses isolated from poultry (5 strains) and humans (2 strains) in Vietnam and tested their virulence in mice. The results showed that the H5N1 viruses from humans were pathogenic in mice and that one avian isolate was also pathogenic. These findings suggested that the H5N1 viruses circulating in poultry adapted during replication in humans or that strains pathogenic in mice were transmitted directly to humans.     

Molecular characterization of the hemagglutinin and neuraminidase genes of H5N1 influenza A viruses isolated from poultry in Vietnam from 2004 to 2005

Highly pathogenic H5N1 avian influenza A viruses have been spreading among domestic poultry, wild aquatic birds, and humans in many Asian countries since 2003. The largest number of patients, to date, infected with the H5N1 viruses are in Vietnam, where these viruses continue to cause outbreaks in domestic poultry. Here, we molecularly characterized the hemagglutinin and neuraminidase genes of nine H5N1 viruses isolated between January 2004 and August 2005 from domestic poultry in Vietnam. We found that several groups of highly pathogenic H5N1 avian influenza viruses are circulating among these birds, which suggests that H5N1 viruses of different lineages have been introduced into Vietnam multiple times.     

A review of potential image fusion methods for remote sensing-based irrigation management: part II

Satellite-based sensors provide data at either greater spectral and coarser spatial resolutions or lower spectral and finer spatial resolutions due to complementary spectral and spatial characteristics of optical sensor systems. In order to overcome this limitation, image fusion has been suggested to obtain higher spatial and spectral resolution images at the same time. Image fusion has been a valuable technique in digital image analysis and comparison because of the availability of multi-spatial and multispectral images from satellite and airborne sensors. It has been applied to merge coarser spatial resolution of multispectral images with a finer spatial resolution panchromatic image to enhance visual apprehension and to provide images that are more informative. Part I companion paper presented and discussed the image downscaling methods. In this paper (part II), the main objective is to review existing image fusion methods for their capability to downscale coarser spatial resolution images for irrigation management applications. A literature review indicated that image fusion methods have not been actively used in obtaining high-resolution land surface temperature (LST) and evapotranspiration (ET) images for irrigation management. However, there is a great potential for applying image fusion methods to retrieve finer LST and ET images from coarser thermal images by fusing them with finer non-thermal color or panchromatic images for irrigation scheduling and management purposes.     

Evaluation of genetic diversity in Korean soybean landraces by protein banding patterns using high-throughput screening

The agronomic performance and storage protein patterns of 722 soybean landraces collected from eight geographically different Korean locations were investigated. The days to 50% flowering, days to maturity, and 100-seed weight ranged from 68.9 to 71.9 (d), 140.1 to 146.6 (d), and 22.4 to 26.8 (g), respectively. High-throughput protein profiling electrophoresis was performed, and the banding patterns were analyzed. Among the 722 soybean landraces, lipoxygenase bands were found to be absent in 21 lines. Nei’s gene diversity (h) ranged from 0 to 0.2642, with an average value of 0.1565. The mean coefficient of gene differentiation (Gst) was 0.0944, and the estimated gene flow (Nm) in the population was 4.7971. In a correlation matrix between the agronomic traits and protein banding patterns, the acidic banding pattern was significantly associated with all the other factors. The phenotypic and genotypic differences of the collection areas were evaluated, and the excellent soybean lines with high-value proteins, including 11S globulins, or without antinutritional factors such as lipoxygenase and trypsin inhibitor were selected.     

Localisation of swine hepatitis E virus in experimentally infected pigs

The distribution of intravenously inoculated swine hepatitis E virus (HEV) was assessed by in situ hybridisation for a period of 50 days. Evidence of apparent clinical disease was found in only one pig in the HEV infected group. The only gross lesion observed was mildly enlarged mesenteric lymph nodes at 50 days post infection (dpi). Histopathologically, mild lymphoplasmacytic infiltration and focal hepatocellular necrotic lesions were found in HEV-infected pigs. Swine HEV nucleic acids were detected by RT-PCR in the faeces at 3 dpi in 100% of the 18 pigs infected with the virus. Thereafter, the number of positives declined.The most consistent and intense signal was found in the liver of infected animals using in situ hybridisation. The positive cells were hepatocytes, Kupffer cells, bile epithelial cells and interstitial lymphocytes. Swine HEV RNA was localised in the cytoplasm of the hepatocytes, with a slightly granular pattern of staining, but hybridisation signals were not observed in degenerative or vacuolated hepatocytes. HEV was much less frequently detected in extrahepatic tissues such as lymph nodes, tonsil, spleen and small and large intestine. It was concluded that swine HEV had replicated primarily in the hepatocytes and infection resulted in subclinical infection with minimal histopathological changes in the liver.     

Comparison of a new synthetic, peptide-derived, polyclonal antibody-based, immunohistochemical test with in situ hybridisation for the detection of swine hepatitis E virus in formalin-fixed, paraffin-embedded tissues

A synthetic, peptide-derived, polyclonal antibody-based, immunohistochemical test was developed to detect swine hepatitis E virus (HEV) and was compared with in situ hybridisation for the detection of HEV in formalin-fixed, paraffin-embedded tissues from experimentally infected pigs. Solid-phase peptide synthesis was used to generate peptides from swine HEV open reading frame 2, and the purified peptides were injected into rabbits to produce polyclonal antibodies. The specificity and sensitivity of the test were both 100%. Liver was most consistently positive for swine HEV antigen and RNA by immunohistochemistry and in situ hybridisation, respectively, but both were detected much less frequently in extrahepatic tissues such as lymph node, tonsil, spleen, and intestine. Swine HEV antigen and RNA showed a similar distribution in virus-infected hepatocytes in serial sections. The novel test developed in this study is suitable for consistently detecting swine HEV antigen in formalin-fixed, paraffin-embedded tissues.     

Slow-binding inhibition of soybean lipoxygenase-1 by dodecyl gallate

Dodecyl gallate inhibited the soybean lipoxygenase-1 (EC 1.13.11.12, type-1) catalyzed peroxidation of linoleic acid with an IC50 of 0.007 microM without being oxidized. The progress curves for enzyme reactions were recorded by both spectrophotometric and polarographic methods, and the inhibition kinetics revealed competitive and slow-binding inhibition. Both the initial velocity and steady-state rate in the progress curve decreased with increasing dodecyl gallate. The kinetic parameters that described the inhibition by dodecyl gallate were evaluated by nonlinear regression fits.