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Background: Population differentiation and their adaptation to a particular environment depend on their ability to respond to a new environment. This, in turn is governed to an extent, by the degree of phenotypic plasticity exhibited by the populations. The populations of same species inhabiting different climatic conditions may differ in their phenotypic plasticity. Himalayan populations of Arabidopsis thaliana originating from a steep altitude are exposed to different climatic conditions ranging from sub-tropical to temperate. Thus they might have experienced different selection pressures during evolution and may respond differently under common environmental condition. Results: Phenotypic plasticity and differentiation of natural populations of A. thaliana grown under common garden and controlled conditions were determined. A total of seventeen morphological traits, their plasticity, association between traits and environment were performed using 45 accessions from three populations. Plants from different altitudes differed in phenotypes, their selection and fitness under two conditions. Under both the conditions lower altitude population was characterized by higher leaf count and larger silique than higher and middle altitude population. Flowering time of high altitude population increased while that of low and medium altitude decreased under controlled condition compared to open field. An increase in seed weight and germination was observed for all the population under open field than controlled. Rosette area was under divergent selection in both the condition. The heritability of lower altitude population was the highest under both the conditions, where as it was the least for higher altitude population further indicating that the high altitude populations are more responsive towards phenotypic changes under new environmental conditions. Ninety-nine percent of variability in traits and their plasticity co-varied with the altitude of their origin. The population of high altitude was more plastic and differentiated as compared to the lower altitude one. Conclusions: Arabidopsis thaliana population native to different altitudes of the west Himalaya responds differently when grown under common environments. The success of high altitude population is more in common garden than the controlled conditions. The significant variability in phenotype and its association with altitude of origin predicts for non-random genetic differentiation among the populations. [ABSTRACT FROM AUTHOR]

Background Interactions between aboveground and belowground terrestrial communities are often mediated by plants, with soil organisms interacting via the roots and aboveground organisms via the shoots and leaves. Many studies now show that plant genetics can drive changes in the structure of both above and belowground communities; however, the role of plant genetic variation in mediating aboveground-belowground interactions is still unclear. We used an earthworm-plant-aphid model system with two aphid species (Aphis fabae and Acyrthosiphon pisum) to test the effect of host-plant (Vicia faba) genetic variation on the indirect interaction between the belowground earthworms (Eisenia veneta) on the aboveground aphid populations. Results Our data shows that host-plant variety mediated an indirect ecological effect of earthworms on generalist black bean aphids (A. fabae), with earthworms increasing aphid growth rate in three plant varieties but decreasing it in another variety. We found no effect of earthworms on the second aphid species, the pea aphid (A. pisum), and no effect of competition between the aphid species. Plant biomass was increased when earthworms were present, and decreased when A. pisum was feeding on the plant (mediated by plant variety). Although A. fabae aphids were influenced by the plants and worms, they did not, in turn, alter plant biomass. Conclusions Previous work has shown inconsistent effects of earthworms on aphids, but we suggest these differences could be explained by plant genetic variation and variation among aphid species. This study demonstrates that the outcome of belowground-aboveground interactions can be mediated by genetic variation in the host-plant, but depends on the identity of the species involved. [ABSTRACT FROM AUTHOR]

The article discusses a study that assesses the co-infection of hepatitis E virus (HEV) with hepatitis B virus (HBV) in HBV-DNA positive cases. The study includes 40 adult patients from various liver diseases with high level of ALT and AST. It also reveals that HBV and HEV are the major cause of acute and chronic live diseases.

The article presents a study which investigates ORF2 protein expression of torque teno virus (TTV) genotype1. The study amplified ORF2 region of TTV genotype1 using gene specific primers and confirmed expressed protein by western blotting. Results reveal that protein of ORF2, which was successfully expressed by western blotting, is immunogenic because protein expressed by TTV genotype1 is producing genotype-specific immunity.