Impaired larval development in broods of eelpout (<Emphasis Type="Italic">Zoarces viviparus</Emphasis>) in Danish coastal waters

Eelpouts (Zoarces viviparus), a viviparous fish, were sampled in Danish coastal waters during October and November 2001 and 2002, in ten different areas, which are receiving effluents from cities and industry to more or minor degree. The presence of gross abnormalities in eelpout broods has been suggested to be a useful biomarker of the impact of hazardous substances on fish reproduction in the marine environment as chronic exposure to various substances has the potential to induce severe developmental defects in fish embryos and larvae. Relatively high frequencies of female eelpouts (20–53) with elevated levels (>5) of larvae with developmental defects in the broods were found in four shallow fjords with effluents from larger cities and industry compared to areas. Deformations like spiral or bend shapes of the spinal axis, cranio-facial defects, eye lesions or loss of eyes were the dominating types. In some ofthe areas with the highest incidences of developmental defects, the adults had significantly enlarged livers, which may also be a possible effect caused by contaminant exposure. In two of the areas, relatively high frequencies of the broods contained larvae, which had died late but without any visible developmental defects. These two areas were affected by severe oxygen depletion prior to sampling time suggesting that examination of broods in the eelpout may include not only impact of hazardous substances but also effect of eutrophication-related problems on fish reproduction in the marine environment.     

Properties of cod metallothionein,its presence in different tissues and effects of Cd and Zn treatment

One isoform of the low-molecular-weight metal-binding protein metallothionein (MT) has been isolated from the liver of Atlantic cod by size-exclusion and ion-exchange chromatography. Cod MT contained 33% cysteine, no aromatic amino acids or arginine. As is the case for other piscine MTs, the N-terminus of cod MT lacked the asparagine in position 4 which is present in mammalian MTs. In addition, cod MT differed from all other vertebrate MTs described in that the N-terminal methionine was not acetylated. Antibodies were raised in rabbits against hepatic MT from cod by repeated injections of native protein mixed with adjuvant. Anti-cod MT antisera cross reacted with similarly-sized proteins in liver, brain, anterior kidney, posterior kidney, spleen, intestine, gills and ovaries. The putative MT in cod brain migrated differently to that of the other tissues in native gel electrophoresis. Intraperitoneally injected Cd (1 mg/kg) was nearly entirely associated with the MT-peak in hepatic and renal cytosols, whereas a single injection of Zn (10 mg/kg) resulted in increases in all cytosolic Zn pools of the liver and no apparent change in cytosolic Zn, Cu, Ni or Cd in kidney.     

Effects of Salinity and Soil–Drying on Radiation Use Efficiency,Water Productivity and Yield of Quinoa (Chenopodium quinoa Willd.)

Drought and salinity reduce crop productivity especially in arid and semi‐arid regions, and finding a crop which produces yield under these adverse conditions is therefore very important. Quinoa (Chenopodium quinoa Willd.) is such a crop. Hence, a study was conducted in field lysimeters to investigate the effect of salinity and soil–drying on radiation use efficiency, yield and water productivity of quinoa. Quinoa was exposed to five salinity levels (0, 10, 20, 30 and 40 dS m^?1) of irrigation water from flower initiation onwards. During the seed‐filling phase the five salinity levels were divided between two levels of irrigation, either full irrigation (FI; 95 % of field capacity) or non‐irrigated progressive drought (PD). The intercepted photosynthetically active radiation was hardly affected by salinity (8 % decrease at 40 dS m^?1) and did not differ significantly between FI and PD. Radiation use efficiency of dry matter was similar between salinity levels and between FI and PD. In line with this, no negative effect of severe salinity and soil–drying on total dry matter could be detected. Salinity levels between 20 and 40 dS m^?1 significantly reduced the seed yield by ca. 33 % compared with 0 dS m^?1 treatment owing to a 15–30 % reduction in seed number per m², whereas the seed yield of PD was 8 % less than FI. Consequently, nitrogen harvested in seed was decreased by salinity although the total N‐uptake was increased. Both salinity and drought increased the water productivity of dry matter. Increasing salinity from 20 to 40 dS m^?1 did not further decrease the seed number per m² and seed yield, which shows that quinoa (cv. Titicaca) acclimated to saline conditions when exposed to salinity levels between 20 and 40 dS m^?1.     

Characterization of circulating antibodies against Chlamydia psittaci in turkeys.

Plasma and joint fluids from turkeys experimentally inoculated with Chlamydia psittaci strain TT3 were evaluated by immunoblotting to identify antibodies elicited by chlamydial antigens during the course of infection. Protein antigens from elementary bodies of TT3 were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and transferred electrophoretically to nitrocellulose before being probed with plasma or synovial fluid from TT3-inoculated birds. The major outer-membrane protein (MOMP), the 60,000-molecular-weight proteins, and a 97,400-molecular-weight protein were the predominant antigens recognized by IgG in the plasma and joint fluids. Plasma IgG specific for the 97,400 protein band was first detectable at day 10 postinoculation (PI). Antibodies to the 60,000-molecular-weight protein and MOMP were first detected at days 14-17 PI and at days 7-10 PI, respectively, in some birds, and as late as days 36-42 PI and days 42-70 PI in others. The antibodies were still present at day 142 PI. Immunoblotting techniques indicated that the antigens to which these antibodies were reacting were protein. These observations may have implications for the development of serodiagnostic assays as well as the identification of potential proteins for subunit immunogens in birds.     

Evidence of long distance airborne transmission of Aujeszky's disease (pseudorabies) virus

Aujeszky's disease has been the subject of an eradication campaign in Denmark since 1980. A detailed knowledge of the virus strains present in the country was provided by restriction fragment analyses of older clinical isolates, and of isolates from all the virologically confirmed outbreaks since 1985. The introduction of foreign strains into southern border areas was demonstrated during the winters of 1984/85, 1986/87 and 1987/88. An epizootic during the winter of 1987/88 was shown to correlate with an unusual predominance of southerly winds. Both conventional and specific pathogen free herds became infected. A herd level case-control analysis of the outbreaks during the winter of 1987/88 revealed that there was a positive correlation between the risk of infection and the size of the herd. The observations support the hypothesis of airborne transmission of the disease.     

Resistance to the cabbage root fly, Delia radicum, within Brassica fruticulosa

Two transgenic Bt rice lines, KMD1 and KMD2, both containing a synthetic cry1Ab gene from Bt, were crossed with conventional rice varieties. The inheritance of resistance to SSB of KMD1 and KMD2was investigated through LSB and field examination of their progenies, e.g. F₁, BC₁ and F₂ populations. In LSBs, 100.0% of newly hatched SSB larvae died on the second day after feeding on leaf tissues of F₁ and GUS positive BC₁ plants, of which the area of leaf tissues consumed by SSB is also similar to that of transgenic parents. These results imply that the resistance of Bt rice to SSB is dominantly controlled and could be easily exploited in hybrid rice production. Field evaluation showed that segregation ratios for SSB resistance to susceptibility in BC₁ populations fit the ratio of 1:1, which was also confirmed by LSBs. However, in F₂ populations, the ratio was significantly smaller than 3:1 for resistant to susceptible plants in all 6 indica × japonica (KMD1 and KMD2) crosses, though it fitted 3:1 in all 4 japonica × japonica crosses. The results implied that the resistance of Bt rice to SSB was controlled by a dominant gene which was present in a homozygous condition in both KMD1 and KMD2, but the inheritance could be affected by other factors. Assays for Cry1Ab protein showed that, in most crosses, the content of Cry1Ab is significantly higher in leaves of GUS positive F₁, BC₁ and F₂ plants than that in transgenic Bt parent plants, which accounts for the high resistance observed in these plants to SSB. This revised version was published online in July 2006 with corrections to the Cover Date.     

Components of Response in Barley Anther Culture

Anther culture response with 17 widely-grown varieties and one model variety of barley was studied with one replication from field-grown donor plants and one replication from a growth-chamber. Plants were regenerated from all 18 varieties and green plants were obtained from 16 of them. On average, 1.6 green plants were obtained per 100 cultured anthers from all the material. Estimated variance components for the formation of embryos/callus from the anthers were dominated by the effects of the genotypes and interactions between plant material and environments which together accounted for 60.1 and 17.0 % of the total variation respectively, while environments were nonsignificant for this character. Plant regeneration from embryos/callus were not significantly influenced by either genotype or environments. Components of variance for green plant formation were dominated by the effects of the genotypes, accounting for 73.2 % of the total variation, and a smaller effect from environments accounting for 11.2% of the total variation. Main effects from genotypes on the percentage of green regenerants divided 7 varieties into two distinct groups, indicating that major genetic factors were involved. The genetic basis for green plant regeneration seems different from that governing embryo formation. The results are discussed with respect to the possible prediction of anther culture response for new barley hybrids, as a means for directing the use of barley anther culture towards material that responds well.     

Genic microsatellite markers for discrimination of spinach cultivars

A set of simple sequence repeat (SSR or microsatellite) markers was used to discriminate a collection of 33 Spinacia oleracea hybrid cultivars from seven different breeding stations all over the world. All SSR markers were genic microsatellite markers located in coding or non-coding regions of genes of known function. Cluster analysis based on 13 of the SSR markers showed that the spinach hybrids grouped into three clusters. The first two clusters consisted of European spinach types, which were well discriminated according to their origin from different breeding stations. The third cluster was a mixture of Asian as well as European types of spinach. Subclusters in this group did not reflect differences in morphology, earliness or company origin. The data show that genic microsatellites are a powerful tool for discrimination of spinach cultivars.     

Electrophoretic Characterization of Quinoa Seed Proteins

Quinoa (Chenopodium quinoa Willd) is an important domesticated food crop of the Andean highlands with potential as an alternative crop elsewhere. Among its most attractive characteristics are the quantity and favorable amino acid balance of the seed proteins. The objective of this study was to characterize quinoa seed proteins by electrophoretic mobility, solubility fractionation, and genetic variability from a wide genetic base. Electrophoretic profiles of denatured albumin, globulin, prolamin, and glutelin solubility fractions demonstrated that quinoa seed polypeptides could be classified as either albumin or globulin with most predominant polypeptides in the globulin fraction. Insignificant amounts of protein were present in the prolamin fraction and all polypeptides in the glutelin fraction had identical electrophoretic mobilities to albumins and globulins. Three globulin polypeptides of 34.3, 35.6, and 36.2 kilodaltons in size were highly variable within and among the accessions examined and appear to be coded by at least two loci. Two-dimensional peptide mapping revealed that these three polypeptides were homologous. These highly variable markers could be used for identification and classification of germplasm and elucidation of systematics and genetic variability within the quinoa germplasm pool. All other major polypeptides were electrophoretically invariant among the accessions examined.