Plant traits and phenotypic variability effect on the phytomass production of Stipagrostis ciliata (Desf.) De Winter

A process of continuous degradation of plant communities, due mainly to long-term overgrazing has been revealed by most ecological studies in North African arid climate. Notably, this degradation appeared across the depletion of perennial grass species exhibiting low density in the majority of range ecosystems. This study aimed to examine the phenology and the aboveground phytomass production of Stipagrostis ciliata (Desf.) De Winter accessions, a perennial grass, growing under the same environment but coming from different climates of Tunisia. Additionally, the extent of genetic variation in phenological parameters, root and shoot phytomass productivity and the correlations among these parameters were also analyzed. Significant differences in all morphological parameters of S. ciliata accessions were revealed by ANOVA test and were corroborated with significant and positive correlation indicated by Pearson’s correlation analysis. Plant diameter, biovolume, root biomass with protective sleeve and spike number exhibited significant differences and high distinctiveness between S. ciliata accessions. Tukey’s HDS tests indicated the presence of three groups of accessions. Principal component analysis (PCA) applied on a table with eight observations and 13 variables, and dispersion of S. ciliata accessions on the first two axes of PCA confirmed the presence of three groups of accessions. Trait variability in the field for the five accessions is more likely to be the result of phenotypic plasticity rather than of genetic differentiation between accessions. Overall, the characterization of S. ciliata accessions exhibited significant differences in terms of morphological and biomass productivity.     

Fungal Smn and Spf30 homologues are mainly present in filamentous fungi and genomes with many introns: implications for spinal muscular atrophy

Spinal muscular atrophy is an important rare genetic disease characterized by the loss of motor neurons, where the main gene responsible is smn1. Orthologous genes have only been characterized in a single fungal genome: Schizosaccharomyces pombe. We have searched for putative SMN orthologues in publically available fungal genomes, finding that they are predominately present in filamentous fungi. SMN binding partners and the SPF30 SMN paralogue, which are all involved in mRNA splicing, were found to be present in a similar but non-identical subset of fungal genomes. The Saccharomycces cerevisiae yeast genome contains neither smn1 orthologues nor paralogues and it has been suggested that this might be related to the low number of introns in this yeast. Here we have tested this hypothesis by looking at other fungal genomes. Significantly, we find that fungal genomes with high numbers of introns also possess an SMN orthologue or at least its paralogue, SPF30.     

Characterization of an infectious pancreatic necrosis virus from rainbow trout fry(Onhorhynchus mykiss) in West Ukraine

<正>Dear Editor,Aquatic birnaviruses are a group within the family Birnaviridae that comprise isolates from fish and shellfish from both fresh-and seawater(Woo and Bruno,1999).Members of the family Birnaviridae are icosahedral viruses approximately 60 nm in diameter composed of five polypeptides and two segments of double-stranded RNA(Dixon et al.,2008).In this report,an aquatic birnavirus was isolated from rainbow trout fry,Onhorhynchus myki-     

An ArabidopsisSUPERMAN-like gene,AtZFP12, Expressed at Shoot Organ Boundaries Suppresses cell Growth.

Arabidopsis SUPERMAN (SUP) and its family members have been implicated in flower organogenesis and plant morphogenesis via the regulation of division or growth of cells. In this study, we characterized a new SUP-like zinc finger gene (AtZFP12). This gene is expressed around the bases of the axillary buds and at the junction between the inflorescence axis and flower stalks. It is also expressed at the boundary between the meristematic and elongation zones in root tips. Overexpression of its cDNA in transgenicArabidopsis reduced cell expansion, resulting in dwarfed plant growth. These results suggest the potential role ofAtZFP12 in the regulation of cell growth during the establishment of SOB in the shoot and transition zones in root tips.