Brachypodium distachyon seedling growth visualization under osmotic stress and overexpression of MIR7757 to increase drought tolerance

Official URL: http://risc01.sabanciuniv.edu/record=b1817257 (Table of Contents)

Brachypodium distachyon a monocot model plant has facilitated the downscaling for studying the most important cereal crops of the world both genetically and phenetically. This owes to its dwarf stature, small genome size and rapid life cycle which was utilized in our research for analysing its morphological features under osmotic stress. The purpose of this study was to visualize Brachypodium seedlings under osmotic pressure to observe morphological adaptation under drought-like conditions. It was found that Brachypodium displays the typical adaptive mechanisms of cereal plants mainly root apical meristem showing lateral hair growth and stunted growth. The root cells also displayed change in single cell morphology by swelling into compartment like structures as compared to non-stressed cells. This observation was made in the elongation and maturation zones of the root. Lateral hair growth was observed from the root apical meristem after 18 hours of PEG-mediated osmotic stress. Brachypodium not only manifests physiological adaptations to drought stress but also elicits molecular adaptation to counter it. To explore the genetic basis of drought tolerance the microRNAs involved in water deficit were traced out through a reverse genetics approach. The T-DNA mutant library of Brachypodium distachyon allowed for the investigation of a newly discovered microRNA miR7757 involved in water deficit to be overexpressed in Brachypodium to rapidly produce drought tolerant varieties bypassing conventional breeding techniques.