Abstract Detail

Ecology

Das, Aayudh [1], Preston, Jill [2].

Growth trait and gene expression data suggest that above-freezing cold adaptation in Pooideae grasses predates drought adaptation.

Future climate projections predict increased aridity (drought) and seasonal temperature extremes that will likely affect the distribution of plants. Like grasses in general, members of subfamily Pooideae - containing important crops such as wheat, oats, and barley - live in some of the world's severest terrestrial environments, from frigid boreal zones to the arid wind-swept steppe. Phylogenetic history indicates that like aridification, the major cooling event that gave rise to the expansion of the modern temperate-continental-boreal zones, occurred at the Eocene-Oligocene boundary approximately 34 million years ago (mya), around the time when the major Pooideae tribes were diversifying. We hypothesized that that cold adaptation may have predated drought adaptation because ancestors of all major lineages of Pooideae have originated in a temperate microniche. To test my hypothesis, we included Pooideae tribes (Meliceae, Stipeae, and Brachypodieae) that span in the period of time where this aridification and cooling was occurring and analyzed different types of physiological traits and fitness traits to measure stress resistance. Our analysis shows an overlap between the tribes for cold stress and unique response between the tribes for drought. Moreover, a transcriptome profiling of two focal species N. pulchra and B. distachyon reflected a very similar pattern. This indicates that it is possible that cold might have evolved much earlier in the pooideae ancestors even before the E-O boundary with aridification and global cooling.

1 - University Of Veromnt, Plant Biology, 63 Carrigan Drive, 111 Jeffords Hall, Burlington, VT, 05405, United States
2 - University Of Vermont, Plant Biology, 63 Carrigan Drive, 111 Jeffords Hall, Burlington, VT, 05405, United States

Keywords:
Drought
abiotic stress
Transcriptome
RNA Seq
climate
Grass.

Presentation Type: Oral Paper
Session: ECO5, Ecology: Stress
Location: /
Date: Thursday, July 22nd, 2021
Time: 1:15 PM(EDT)
Number: ECO5004
Abstract ID:833
Candidate for Awards:Ecological Section Best Graduate Student Paper