Ecological-genetic aspects of trophic preference partitioning in a micro-assemblage of oak herbivores

Trophic niche partitioning among five most common herbivore species was described in respect to the stiffness of the leaves consumed on two trees of pubescent oak. Using discelectrophoresis procedure, genotypes at nonspecific protein loci were detected in two herbivore species, Tortrix viridana (Lepidoptera, Tortricidae) (Pt-2 locus) and Neuroterus quercusbaccarum (Hymenoptera; Cynipidae) (Pt-1 locus). Each locus was represented in studied samples by two alleles, F and S. Significant intra-species partitioning occurred among corresponding genotype classes in these two species. The mean niche overlap measured by Czechanowski index was the lowest (0.324 +/- 0.046) between genotype classes from different species. The intermediate values of this index (0.420 +/- 0.029) characterize niche overlap between genotype classes of given species and other species The highest values correspond to niche overlap between different species (0.578 +/- 0.049) or between genotype classes in the same species (0.585 +/- 0.078). The distribution of gypsy moth (Lymantria dispar) specimens along the leaf stiffness gradient significantly differed from that of T. viridana (FS-genotype class) and coincided with distribution of two other genotypes of the same species. The distribution of T. viridana (SS-genotype class) along the leaf stiffness gradient significantly differed from analogous distribution of heterozygote FS-genotype class of N. quercusbaccarum but was similar with distribution of homozygote FF and SS of the same species. These results means that different genotype classes in the same species interact differently with other species and even with different genotype classes of other species in the micro-community. Different genotypes of one species show different response to leaf stiffness and therefore unequally interact with each other as well as with different species.     

The effect of fodder plant genotype on the variation of larval fitness traits in genotype classes of green oak leafroller moth

The effect of genetic variation of oak (Quercus pubescens L. and Q. petraea L.) on the genotype fitness components in green oak leafroller moth larvae (Tortrix viridana L.) at esterase (Est-4) and protease (Pts-4) loci was studied. The samples of larvae were collected from nine oak trees, whose genetic variation was assayed by RAPD-PCR using primer OPA14. The contributions of the factors of oak species/genotype and green oak leafroller moth genotype and their interaction to the variation of important size-related traits of the larvae were evaluated by two-way ANOVA. It was shown that the same larval genotype can display maximum fitness on the trees of one species or genotype and minimum, on the trees of other species or genotype. The interactions between the oak genotype and green oak leafroller moth genotype factors lead to the relationships that appear in statistically significant associations between genotype classes of green oak leafroller moth and oak. These results are discussed from the standpoint of a recently developed new field, community or ecosystem genetics.     

Identification of structural DNA variations in human cell cultures after long-term passage

Random amplified polymorphic DNA (RAPD) analysis was adapted for genomic identification of cell cultures and evaluation of DNA stability in cells of different origin at different culture passages. DNA stability was observed in cultures after no more than 5 passages. Adipose-derived stromal cells demonstrated increased DNA instability. RAPD fragments from different cell lines after different number of passages were cloned and sequenced. The chromosomal localization of these fragments was identified and single-nucleotide variations in RAPD fragments isolated from cell lines after 8–12 passages were revealed. Some of them had permanent localization, while most variations demonstrated random distribution and can be considered as de novo mutations.     

Microbial stratification in low pH oxic and suboxic macroscopic growths along an acid mine drainage

Macroscopic growths at geographically separated acid mine drainages (AMDs) exhibit distinct populations. Yet, local heterogeneities are poorly understood. To gain novel mechanistic insights into this, we used OMICs tools to profile microbial populations coexisting in a single pyrite gallery AMD (pH ∼2) in three distinct compartments: two from a stratified streamer (uppermost oxic and lowermost anoxic sediment-attached strata) and one from a submerged anoxic non-stratified mat biofilm. The communities colonising pyrite and those in the mature formations appear to be populated by the greatest diversity of bacteria and archaea (including ‘ARMAN'' (archaeal Richmond Mine acidophilic nano-organisms)-related), as compared with the known AMD, with ∼44.9% unclassified sequences. We propose that the thick polymeric matrix may provide a safety shield against the prevailing extreme condition and also a massive carbon source, enabling non-typical acidophiles to develop more easily. Only 1 of 39 species were shared, suggesting a high metabolic heterogeneity in local microenvironments, defined by the O₂ concentration, spatial location and biofilm architecture. The suboxic mats, compositionally most similar to each other, are more diverse and active for S, CO₂, CH₄, fatty acid and lipopolysaccharide metabolism. The oxic stratum of the streamer, displaying a higher diversity of the so-called ‘ARMAN''-related Euryarchaeota, shows a higher expression level of proteins involved in signal transduction, cell growth and N, H₂, Fe, aromatic amino acids, sphingolipid and peptidoglycan metabolism. Our study is the first to highlight profound taxonomic and functional shifts in single AMD formations, as well as new microbial species and the importance of H₂ in acidic suboxic macroscopic growths.     

Intraspecific chemical variability of the leaf essential oil of Juniperus phoenicea subsp. turbinata from Corsica

The composition of 50 samples of essential oil of individual plants of Juniperus phoenicea subsp. turbinata from Corsica was investigated by GC, GC-MS and 13C NMR. alpha-Pinene, beta-phellandrene, alpha-terpinyl acetate, Delta-3-carene, myrcene and alpha-phellandrene were found to be the main constituents. The results were submitted to cluster analysis and discriminant analysis which allowed two groups of essential oils to be distinguished with respect to the content of alpha-pinene, beta-phellandrene and alpha-terpinyl acetate.     

A Serological Survey of Ruminant Livestock in Kazakhstan During Post-Soviet Transitions in Farming and Disease Control

The results of a serological survey of livestock in Kazakhstan, carried out in 1997–1998, are reported. Serum samples from 958 animals (cattle, sheep and goats) were tested for antibodies to foot and mouth disease (FMD), bluetongue (BT), epizootic haemorrhagic disease (EHD), rinderpest (RP) and peste des petits ruminants (PPR) viruses, and to Brucella spp. We also investigated the vaccination status of livestock and related this to changes in veterinary provision since independence in 1991. For the 2 diseases under official surveillance (FMD and brucellosis) our results were similar to official data, although we found significantly higher brucellosis levels in 2 districts and widespread ignorance about FMD vaccination status. The seroprevalence for BT virus was 23%, and seropositive animals were widespread suggesting endemicity, despite the disease not having being previously reported. We found a few seropositives for EHDV and PPRV, which may suggest that these diseases are also present in Kazakhstan. An hierarchical model showed that seroprevalence to FMD and BT viruses were clustered at the farm/village level, rather than at a larger spatial scale. This was unexpected for FMD, which is subject to vaccination policies which vary at the raion (county) level.     

Influence of genetic variation of oak trees as a nutrient substrate adaption of the pea green oak leaf-roller

The influence of the genetic variation of the DNA (RAPD polymerase chain reaction, primer OPA-14) of two oak species (Quercus pubescens L. and Q. petraea L.) on the variation of certain important fitnesslinked traits of the imago of the pea green oak leaf-roller (Tortrix viridana L.) in different classes of genotypes and allozyme loci is studied. The results obtained demonstrate that pea green oak leaf-roller individuals of the same genotype class may possess maximal fitness (a component associated with fecundity and body size) to trees of one genotype and minimal fitness to trees of another genotype. The interaction of the two factors, oak genotype—pea green oak leaf-roller genotype, leads to the appearance of links between the genotype classes of the leaf-roller and the oak tree. The results obtained are discussed from the point of view of a new area of research, community or ecosystem genetics, a field that has only recently developed.