This study presents a landslide susceptibility assessment for the Caspian forest using frequency ratio and index of entropy models within geographical information system. First, the landslide locations were identified in the study area from interpretation of aerial photographs and multiple field surveys. 72 cases (70 %) out of 103 detected landslides were randomly selected for modeling, and the remaining 31 (30 %) cases were used for the model validation. The landslide-conditioning factors, including slope degree, slope aspect, altitude, lithology, rainfall, distance to faults, distance to streams, plan curvature, topographic wetness index, stream power index, sediment transport index, normalized difference vegetation index (NDVI), forest plant community, crown density, and timber volume, were extracted from the spatial database. Using these factors, landslide susceptibility and weights of each factor were analyzed by frequency ratio and index of entropy models. Results showed that the high and very high susceptibility classes cover nearly 50 % of the study area. For verification, the receiver operating characteristic (ROC) curves were drawn and the areas under the curve (AUC) calculated. The verification results revealed that the index of entropy model (AUC = 75.59 %) is slightly better in prediction than frequency ratio model (AUC = 72.68 %). The interpretation of the susceptibility map indicated that NDVI, altitude, and rainfall play major roles in landslide occurrence and distribution in the study area. The landslide susceptibility maps produced from this study could assist planners and engineers for reorganizing and planning of future road construction and timber harvesting operations.

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The incidence, distribution, and variation of simple sequence repeats (SSRs) in viruses is instrumental in understanding the functional and evolutionary aspects of repeat sequences. Full-length genome sequences retrieved from NCBI were used for extraction and analysis of repeat sequences using IMEx software. We have also developed two MATLAB-based tools for extraction of gene locations from GenBank in tabular format and simulation of this data with SSR incidence data. Present study encompassing 147 Mycobacteriophage genomes revealed 25,284 SSRs and 1,127 compound SSRs (cSSRs) through IMEx. Mono- to hexa-nucleotide motifs were present. The SSR count per genome ranged from 78 (M100) to 342 (M58) while cSSRs incidence ranged from 1 (M138) to 17 (M28, M73). Though cSSRs were present in all the genomes, their frequency and SSR to cSSR conversion percentage varied from 1.08 (M138 with 93 SSRs) to 8.33 (M116 with 96 SSRs). In terms of localization, the SSRs were predominantly localized to coding regions (∼78%). Interestingly, genomes of around 50 kb contained a similar number of SSRs/cSSRs to that in a 110 kb genome, suggesting functional relevance for SSRs which was substantiated by variation in motif constitution between species with different host range. The three species with broad host range (M97, M100, M116) have around 90% of their mono-nucleotide repeat motifs composed of G or C and only M16 has both A and T mononucleotide motifs. Around 20% of the di-nucleotide repeat motifs in the genomes exhibiting a broad host range were CT/TC, which were either absent or represented to a much lesser extent in the other genomes.

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Nucleotide sequences from the internal transcribed spacers (ITS) of nuclear ribosomal DNA and 5.8S gene were used to infer the phylogeny of Tilia species (represented by 13 distinct populations) growing in different geographical areas of Hyrcanian forests in northern Iran. Four well-supported lineages were revealed, including that of a new species, T. hyrcana, with stellate trichomes on both sides of the leaves and petiole. T. hyrcana is a wellsupported cladospecies, with the ITS sequence and secondary structure following the diagnosable phylogenetic species concept, and is also characterized by a distinct morphology. A controversial species is Tilia rubra subsp. caucasica, with three different forms-an assemblage of taxa characterized by a lack of stellate trichomes on leaves-while Tilia begonifolia is distinguished by stellate trichomes on the underside of both leaves and petiole. The fourth lineage group, T. dastyla, is characterized by the presence of trichomes on the style. A single taxon found in the west of the Hyrcanian forest region is similar to T. begonifolia, but due to the former being located in a distinct group, a reassessment of the diagnostic morphology is recommended. ITS sequence data also suggested a closer relationship between T. rubra and T. begonifolia. Compensatory base change analysis was not strong enough to separate individual species within the Tilia genus. In general, the study supports the utility of ITS sequence data and secondary structure as accessory taxonomic characteristics with which to help clarify the systematics of the Tilia genus.

Pollen grains of 7 species of the genus Rubus L. were investigated using light microscopy (LM) and scanning electron microscopy (SEM). 14 different pollen characters were described, illustrated and compared in the present study. All pollen grains were monad, tricolporate, radially symmetrical, isopolar, and medium in size. As for pollen shape, 3 forms were recognized in the same specimens: prolate, perprolate and prolate-spheroidal. Endopore was located in the middle of colpi. The sculpture of the grains was confirmed to have striate pattern. The size of perforation and the orientation of the muri were compared and appeared to indicate the differences between the species. R.caesius, R. discolor, R. dolichocarpus and R. hirtus appear to have steriate-scabrate sculpture; in contrast, R. hyrcanus Juz., R. persicus Boiss. and R. sanctus Schreber. appear to have meandrical and fingerprint-like sculpture. Perforations are of two types. They are either large or often extending to tectal ridges or minute holes. Characters of pollen grains were proved their usefulness for separating taxa at the specific level. It seems that there is a link between the diversity of pollens and the vegetation habitats.