Other factors than apoplastic ascorbate contribute to the differential ozone tolerance of two clones of Trifolium repens L.

Apoplastic reactive oxygen intermediates, which are formed during the exposure of a higher plant to ozone (O₃), have been proposed to be detoxified by apoplastic ascorbate (ASC). An investigation to determine whether the differential sensitivity of two white clover clones (Trifolium repens L. cv Regal) to O₃ was related with their levels of ASC, glutathione derivatives or with the total antioxidative capacity. In contrast to what might be expected, the sensitive clone of white clover (NC-S) constitutively showed a 72% higher concentration of apoplastic ASC compared to the O₃-tolerant clone (NC-R). Furthermore, NC-S also showed a higher redox status of apoplastic ASC. These results indicate that higher ASC levels in the apoplast of NC-S are not sufficient to induce a higher O₃ tolerance. The redox status, but not the absolute concentration of homoglutathione in the symplast was found to be constitutively higher in NC-R than in NC-S. It is not clear, however, whether homoglutathione is a direct cause of the differential O₃ detoxification capacity of both clones. Total antioxidative capacity measurements ruled out the contribution of other low-molecular antioxidants to the relative tolerance of NC-R. It was concluded that elevated apoplastic ASC levels can not always be sufficient to render a plant O₃ tolerant.     

A multiplex panel of dinucleotide microsatellite markers for the water vole,Arvicola terrestris

We isolated and characterized nine polymorphic dinucleotide microsatellite loci in the fossorial vole Arvicola terrestris Scherman (Shaw). A multiplex panel comprising all nine loci was developed and its application to a set of 31 individuals allowed clear and easy characterization of allele sizes. The number of alleles range from three to 14 per locus with the observed heterozygosity ranging from 0.42 to 0.90. These markers will be useful for analysis of questions concerning population genetic structure and reproductive behaviour.     

Preliminary evaluation of four immunological tests for the early diagnosis of Hypoderma tarandi causing hypodermosis in reindeer

294 serum samples from five Norwegian reindeer herds were examined for antibodies against Hypoderma tarandi L. The first and second larval instars of H. tarandi were tested as antigens in immunodiffusion tests, passive haemagglutination and an Enzyme-Linked Immunosorbent Assay (ELISA). The latter technique, using first instar antigens, produced the best results. A significant difference (P less than 0.1%) was observed between the antibody value of naive reindeer bred in France and those from infected Norwegian herds. No correlation was observed between the antibody titre and the number of warbles recovered at necropsy from the 294 Norwegian reindeer.     

Morphological structure and optical properties of the wings of Morphidae

The morphological structure and optical properties of the wings of 14 species of Morphidae have been investigated. Most of the scales of the iridescent species of Morphidae （Lepidoptera） present a very particular structure. The ground scales, responsible for the major part of the optical properties, are covered by a very regular set of longitudinal ridges. The ridges themselves are constituted by a superposition of lamellae that act locally as a multilayered structure. This very specific morphology leads to both interferences and diffraction effects. The first one is responsible of the brilliant blue coloration of the males, while the second one diffracts this colored light at a very large angle. These two phenomena give to the butterfly a very effective long-range communication system. The morphological characteristics of the scales of the various species are presented in detail. Two types of optical measurement were performed on the iridescent wings of 14 different species of Morphidae： spectroscopic measurements under various incidences and gonioscopic measurements for a given incidence angle and wavelength. The first allows a determination of the index of refraction of the cuticular material. The second leads to the drawing of spatial diffraction maps. It shows that most of the reflected light is diffracted laterally over a very large angle （90° 〈 0 〈 120°, according to the different species） and that this repartition depends of the polarization of incident light. As predicted by previous calculations, the dissymmetric structure of the ridge is responsible for the separation of the polarization modes in the various diffraction orders.     

Nuclear insertions and heteroplasmy of mitochondrial DNA as two sources of intra‐individual genomic variation in grasshoppers

We examined the level of intra‐individual variation in a region of the mitochondrial genome coding for cytochrome oxydase 1 (COI) in two grasshopper species using a clone‐and‐sequence analysis of hundreds of sequences. In both Locusta migratoria and Chortoicetes terminifera, we found that 60–65% of the clones were unique COI‐like sequences. Among these COI‐like sequences, 70–75% diverged by less than 1% from the real mitochondrial haplotypes, and were likely to represent microheteroplasmic molecules. About 20% of the COI‐like sequences diverged by more than 9% from the mitochondrial haplotypes, and generally included stop codons, suggesting that these sequences were nuclear mitochondrial pseudogenes (NUMTs). Only six sequences, diverging by 2–6% from the mitochondrial haplotypes, were identified as potentially misleading in phylogenetic studies. In addition, we found that five sequences from C. terminifera were associated with mobile elements or repetitive DNA families.     

Analysis of pellets of the Grey heron, Ardea cinerea, from colonies in Belgium

Analyses of the contents of pellets of Grey herons from different breeding colonies and breeding seasons indicated that the mammal and invertebrate species included in the heron diet varied between colonies and between years. The large differences in mammal species found in neighbouring heronries suggested the existence of important small-scale variability in the exploitation of mammals. Almost no fish and bird remains were found in the pellets. We believe that most invertebrates, even the smallest ones, were actively taken by the herons. Identification of mammal species composition by means of skulls and hair remains gave different results. The shape of a pellet seemed to be dependent upon the (moisture?) conditions during its formation.