Codominant grasses differ in gene expression under experimental climate extremes in native tallgrass prairie

PeerJ

article

Ava M. Hoffman¹  Meghan L. Avolio³  Alan K. Knapp¹  Melinda D. Smith¹ 

[1] Department of Biology, Colorado State University;Graduate Degree Program in Ecology, Colorado State University;Department of Earth & Planetary Sciences, The Johns Hopkins University

关键词: Andropogon gerardii;    Sorghastrum nutans;    Microarray;    Drought;    Heat wave;    C4 grass;    Dominant species;   

DOI  :  10.7717/peerj.4394

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

Extremes in climate, such as heat waves and drought, are expected to become more frequent and intense with forecasted climate change. Plant species will almost certainly differ in their responses to these stressors. We experimentally imposed a heat wave and drought in the tallgrass prairie ecosystem near Manhattan, Kansas, USA to assess transcriptional responses of two ecologically important C4 grass species, Andropogon gerardii and Sorghastrum nutans. Based on previous research, we expected that S. nutans would regulate more genes, particularly those related to stress response, under high heat and drought. Across all treatments, S. nutans showed greater expression of negative regulatory and catabolism genes while A. gerardii upregulated cellular and protein metabolism. As predicted, S. nutans showed greater sensitivity to water stress, particularly with downregulation of non-coding RNAs and upregulation of water stress and catabolism genes. A. gerardii was less sensitive to drought, although A. gerardii tended to respond with upregulation in response to drought versus S. nutans which downregulated more genes under drier conditions. Surprisingly, A. gerardii only showed minimal gene expression response to increased temperature, while S. nutans showed no response. Gene functional annotation suggested that these two species may respond to stress via different mechanisms. Specifically, A. gerardii tends to maintain molecular function while S. nutans prioritizes avoidance. Sorghastrum nutans may strategize abscisic acid response and catabolism to respond rapidly to stress. These results have important implications for success of these two important grass species under a more variable and extreme climate forecast for the future.

【 授权许可】

CC BY