Choudhary, Shruti2020-08-212024-08-132020-08-212024-08-132019Choudhary, Shruti & Bhardwaj, Pankaj (2019) Studies on adaptive environmental responses in Himalayan Rhododendron arboreumhttp://10.2.3.109/handle/32116/2747Temperate plants acclimatize to survive freezing temperatures, which are otherwise prerequisite in the initiation/transition of a developmental phase. The dominance of Rhododendron arboreum under a highly fluctuating Himalayan environment makes it enticing for genetic structure and functional analysis. In the present study, transcript, small RNA and metabolome libraries from flowers and foliar tissues of reproductive and vegetative seasons were analyzed. The high-quality paired-end reads were assembled into 157,427 non-redundant transcripts and categorized functionally based on gene ontology, pathway, and transcription factor database. The screening for molecular markers identified 35,419 SSR and 811 high-quality SNPs. A comparison of transcript profiles for the vegetative and flowering season tissues revealed that 12,577 unigenes with fluctuating expression were responsible for seasonal adaptations. Additional to the gene interaction networks, 421 ions obtained from LC-MS were annotated to distinct pathways, especially secondary metabolites. Thirdly, 466 conserved and novel miRNAs, 442 precursors, and 27,139 targets were predicted and the miRNAs modulating circadian clock and reproductive development were discussed further. Other than the genes, miRNAs, and compounds held for an active metabolism, signaling, development, and their regulations, supplementary responses to abiotic/biotic stimuli were induced. A multifaceted response not only sponsored the climatic encounters but brought the shift from vegetative to reproductive growth. The genome-wide profiling and the spatiotemporal variation in mRNA and miRNA expression, as well as the nontargeted metabolome, will enhance the understanding of development and tolerance strategies in high altitude tree species.en-USFlowering regulationCircadian clockAdaptationDe novo assemblyAnnotationMolecular markersDifferential expressionMetabolomeMicroR profilingThesisT00871