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Taxaceae and Cephalotaxaceae are the two economically important conifer families. Over the years there has been much controversy over the issue of merging these families. The position of Amentotaxus and Torreya is also ambiguous. Some authors consider them closer to Taxaceae while others deemed them to fit within Cephalotaxaceae. Still, others prefer to raise them to their own tribe. Different morphological, anatomical, embryological and phylogenetic evidence supports one or the other view, making the precise delineation between them unresolved. Here we used an RNAseq-based approach to obtain orthologous genes across the selected species to reconstruct a more robust phylogeny of these families. A total of 233.123 million raw reads were de novo assembled to generate nine different transcript assemblies for the corresponding species. Of the 940 191 assembled transcripts across nine species, we generated 409 734 unigenes, which were clustered into orthologous groups. A total of 331 singlecopy complete orthologous groups were selected for phylogenetic analysis. Maximum-likelihood, maximum-parsimony and Bayesian phylogenetic trees showed a sister relationship between Taxaceae and Cephalotaxaceae. Our analysis supports their distinctiveness at the family level and also shows that Amentotaxus and Torreya fit within Cephalotaxaceae.

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10Rhododendron arboreum, an ecologically prominent species, also lends commercial and medicinal 11 benefits in the form of palatable juices and useful herbal-drugs. The local abundance and survival of the species 12 under highly fluctuating climate make it an ideal model for genetic structure and functional analysis. However, a 13 lack of genomic data has hampered the additional research. In the present study, cDNA libraries from floral and 14 foliar tissues of the species were sequenced to provide a foundation for understanding the functional aspects of 15 the genome and to construct an enriched repository that will promote genomics studies in the genera. Illumina's 33The Himalayas are among the longest altitude-temperature gradients. The ranges are home to roughly 34 two-thirds of the world's Rhododendron species (subgenus Hymenanthes, family Ericaceae) (Singh et al. 2009). 35The high-altitude flora has specific requirements for humidity, temperature, precipitation, and photoperiod 36 (Gugger et al. 2013; Parmesan and Hanley 2015; Komac et al. 2016). Abiotic factors and their interactions with 37 the genotype of an organism primarily affect its growth and distribution pattern. There are unique microclimates 38 and noticeable topographical gradients in the mountainous regions; even a minor variation in the climate could 39 prove vulnerable to the endemic biodiversity (Thuiller et al. 2005). The resultant upward shift in the snowline 40 has already altered the habitat perimeters and phenological characteristics of many species, counting 41Rhododendron genus as well (Xu et al., 2009). A rise in annual temperature not only influences the population 42 structure of a single species but also threatens the ecosystem as a whole, necessitating a timely evaluation of the 43 associated risks (Memmott et al. 2007; Urban 2015). 44Rhododendron arboreum (2n=26) is dispersed from India to China throughout the Himalayas, 45inhabiting the widest temperature range (4.4-19.3°C) (Vetaas 2002). The genus Rhododendron is a source of 46 useful phytochemicals having potential health benefits (Jaiswal et al. 2012). In addition, the species holds 47 ecological, aesthetic, and commercial eminence in India (Singh et al. 2009; Kumar 2012). Due to the economic 48and medicinal values, the plant is being exploited at a faster rate for harvesting flowers, leaves, and wood. 49Furthermore, a decrease in land cover as a result of anthropogenic activities and global climate changes can 50 cause a decline in the diversity. Despite the varying environmental cues, R. arboreum exploited the earlier 51 trends in climatic conditions, which favored its dominance in the landscapes (Ranjitkar et al. 2013). The 52 inherent genetic variability is very well appreciated for the survival of a species in a specific environment. 56One of the frequently employed marker system in genetic diversity and genotype identification studies 57 is the simple sequence repeat (SSR or microsatellite) marker. SSRs are 1-6 base pairs long tandem repeats 58 present b...

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