KSEF RDE: Sex Differences in Desiccation Tolerance, a Novel Approach for Explaining Abiotic Stress Responses in Plants

Agriculture is a significant component of Kentucky's economy, and is negatively impacted by drought. Consequently, understanding plant responses to water shortage will have substantial economic impact in agro-industries in Kentucky. Considerable scientific effort has been placed on unraveling the mechanisms plants use to tolerate extreme water shortage. Desiccation tolerance (DT) is a unique trait that allows tissue to recover from extreme dehydration, and progress has been made towards understanding how plants survive this stress. However, due to the complexity of DT many questions remain. Recovery and protection mechanisms are still unclear, and the range of responses across species and developmental stages is not fully characterized. Although highly desiccation tolerant species can offer insight into strategies for surviving the most extreme drying, studies on intermediate DT could elucidate mechanisms for surviving moderate water stress. Furthermore, differences between members of the same species have potential explanatory power, due to their shared genetic background. Although there has been extensive research on DT, there are few studies on sex differences in DT within a species, which could illuminate details of fine scale adaptation. Marchantia inflexa is an excellent candidate species to fill knowledge gaps in DT because M. inflexa has documented 1) sex differences in DT, 2) intermediate and variable DT, and 3) established genomic resources including a reference genome and transcriptome. Briefly, the proposed work will capitalize on an identified sex difference in DT in M.inflexa to elucidate factors that contribute to DT acquisition. Male and female individuals exhibiting both high and low levels of DT will be selected for expression profiling using high throughput RNAseq, and analyzed to determine gene expression patterns that contribute to DT variation. This study will provide fundamental knowledge of DT, and will inform strategies for reducing the impact of drought-induced crop failure.