Dehydration-induced endodormancy in crown buds of leafy spurge highlights roles for an RVE1-like homolog and hormone signaling cross-talk

New shoot growth from underground adventitious buds of leafy spurge is critical for survival of this invasive perennial weed after episodes of severe abiotic stress. Because global climate change is expected to increase abiotic stress, such as dehydration, objectives of this study include examining the impact that dehydration stress has on molecular mechanisms associated with vegetative reproduction. Greenhouse plants were exposed to mild- (3-day), intermediate- (7-day), severe- (14-day) and extended- (21-day) dehydration treatments, prior to decapitation of aerial tissue and rehydration of soil to induce new vegetative shoot growth. Compared to well-watered control plants, mild-dehydration accelerated new vegetative shoot growth but intermediate- and severe-dehydration treatments both delayed and reduced shoot growth, and 21-day dehydration treatment inhibited initiation of new vegetative shoots and was considered a lethal treatment. Overall, transcriptome profiles revealed that 2109 genes were differentially-expressed (P