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In recent years, low copy nuclear genes became a promising choice in plant phylogeny and systematic studies for being bi-parentally inherited and highly variable, thus possessing more phylogenetically informative sites in contrast to widely used organellar genes. Here, a set of nuclear genes has been fished out from the plant genome database targeting their single copy presence in whole genomes of most of the taxa. Low copy genes, that are yet to be included in molecular phylogenetic studies of plants, were selected. All group of green plants from algae to angiosperm has been considered for validating these markers towards determining both species level and deep lineage hierarchy. The reconstructed phylogeny with selected genes, in present work, exhibited good resolution up to family level with high statistical support. Moreover, NAD, PS54, P4H, CDIPT, and GTF could also serve well up to higher rank clustering. Concatenated species tree through best predicted substitution model with and without third codon position corroborated the prospects of nuclear gene-based phylogeny with some incongruences in the hierarchy. The study acclaimed fourteen low copy nuclear genes concerning the determination of their efficacy toward inferring the taxonomic relationship of green plants which might be used in further molecular systematics and population genetic studies.

Tea (Camellia sinensis, (L.) Kuntze) is considered as most popular drink across the world and it is widely consumed beverage for its several health-benefit characteristics. These positive traits primarily rely on its regulatory networks of different metabolic pathways. Development of microsatellite markers from the conserved genomic regions are being worthwhile for reviewing the genetic diversity of closely related species or self-pollinated species. Although several SSR markers have been reported, in tea, the trait-specific Simple Sequence Repeat (SSR) markers, leading to be useful in marker assisted breeding technique, are yet to be identified. Micro RNAs are short, non-coding RNA molecules, involved in post transcriptional mode of gene regulation and thus effects on related phenotype. Present study deals with identification of the microsatellite motifs within the reported and predicted miRNA precursors that are effectively followed by designing of primers from SSR flanking regions in order to PCR validation. In addition to the earlier reports, two new miRNAs are predicting here from tea expressed tag sequence database. Furthermore, 18 SSR motifs are found to be in 13 of all 33 predicted miRNAs. Trinucleotide motifs are most abundant among all followed by dinucleotides. Since, miRNA based SSR markers are evidenced to have significant role on genetic fingerprinting study, these outcomes would pave the way in developing novel markers for tagging tea specific agronomic traits as well as substantiating non-conventional breeding program.

Seed morphology and germination patterns of 17 halophytes belonging to 10 families of Sundarbans, India, were studied in view of their dispersal, rehabilitation and taxonomic interest. Fruits are mostly one seeded in the investigated taxa, except in Acanthus ilicifolius, Excoecaria agallocha, Sonneratia apetala and Xylocarpus spp. Seeds are inseparable from fruits in Aegialitis rotundifolia, Aegiceras corniculatum, Avicennia spp., Nypa fruticans and the investigated species of Rhizophoraceae. Propagules are mostly dispersed by tidal water. They have to float for some distance prior to establishment for a gradual adjustment of the young ones towards the saline environment. Viviparous germination occurs in all members of Rhizophoraceae, where seed germination takes place immediatelyafter fertilization without any dormancy period. In this case the long hypocotyl comes out of the seed and ultimately from the fruit when the fruit is still attached with the mother plant. This phenomenon is considered as the most complex and highly evolved phenomenon in evolutionary line. In Aegialitis rotundifolia, Aegiceras corniculatum, Avicennia spp. And Nypa fruticans, germination occurs following an incipiently viviparous type where the hypocotyl pierces out of the seed coat but not from the exocarp at the time of dispersal. This incident should be defined more appropriately as cryptovivipary. On the basis of seed characters, an identification key was generated for easy identification of the dispersing units.