Abstract Detail

Desiccation tolerance in bryophytes: perspectives from early career scientists

Marks, Rose [1], McLetchie, D. Nicholas [2].

Tradeoffs in Desiccation Tolerance and Reproductive Allocation.

Desiccation tolerance (DT) is a unique and fascinating strategy, possessed by a small subset of organisms, for surviving periods of water scarcity. Cells with DT are able to dry to very low cellular water content, and then resume normal function upon rehydration. This trait is thought to have been a critical adaptation that allowed plants to colonize land. Desiccation tolerance was subsequently lost in most vascular plant tissues, perhaps as a tradeoff for more complex water management and architecture. However, DT was retained by many bryophytes, and has reappeared multiple times in independent vascular plant lineages. In light of changing global weather patterns and intense local drought conditions, the ability to adapt to changes in water availability is especially relevant. Considerable effort has been invested in unraveling the mechanism of this fascinating trait, but significant gaps in our understanding remain. The trait is complex and involves the sophisticated orchestration of multiple signaling pathways. Past work has focused mostly on between species comparisons, which have been informative, but are insufficient for elucidating the nuances of DT. Further, studies demonstrating tradeoffs between DT and reproduction are limited. Such studies would be quite economically relevant, as agricultural yield is often tied to reproductive output. Here, we have examined DT within a single liverwort species, Marchantia inflexa. We have identified substantial variation in DT within and across populations of this species. Further, we have data suggesting that DT and reproductive allocation tradeoff, and hypothesize that the most desiccation tolerant individuals will show the least reproductive allocation, and that all plants when subjected to desiccation will show reduced reproductive investment when compared to those not subjected to desiccation stress. We have evidence that specific genes involved in conferring DT are down regulated during reproductive life stage, further enforcing the notion that DT and reproduction tradeoff in M. inflexa. Taken together these results indicate that adaptations to different water regimes are possible on a relatively short evolutionary time span, and that investment in sexual reproduction may be influenced by drought stress. This work poises us to investigate further nuances of DT acquisition in M. inflexa.

1 - University of Kentucky, 101 TH Morgan Building, Biology, Lexington, Kentucky, 40506, United States
2 - University Of Kentucky, Department Of Biology, 101 Morgan Build., Lexington, KY, 40506-0225, USA

Keywords:
desiccation
reproductive investment
tradeoff
genetic variation.

Presentation Type: Symposium Presentation
Session: SY11
Location: Salon 8/The Shaw Conference Centre
Date: Tuesday, July 28th, 2015
Time: 3:45 PM
Number: SY11006
Abstract ID:638
Candidate for Awards:None