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Summary Extant land plants consist of two deeply divergent groups, tracheophytes and bryophytes, which shared a common ancestor some 500 million years ago. While information about vascular plants and the two of the three lineages of bryophytes, the mosses and liverworts, is steadily accumulating, the biology of hornworts remains poorly explored. Yet, as the sister group to liverworts and mosses, hornworts are critical in understanding the evolution of key land plant traits. Until recently, there was no hornwort model species amenable to systematic experimental investigation, which hampered detailed insight into the molecular biology and genetics of this unique group of land plants. The emerging hornwort model species,Anthoceros agrestis, is instrumental in our efforts to better understand not only hornwort biology but also fundamental questions of land plant evolution. To this end, here we provide an overview of hornwort biology and current research on the model plantA. agrestisto highlight its potential in answering key questions of land plant biology and evolution.
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Effect of environmental signals on growth and development in mosses
Abstract Plants perceive a multitude of environmental signals and stresses, and integrate their response to them in ways that culminate in modified phenotypes, optimized for plant survival. This ability of plants, known as phenotypic plasticity, is found throughout evolution, in all plant lineages. For any given environment, the specifics of the response to a particular signal may vary depending on the plants’ unique physiology and ecological niche. The bryophyte lineage, including mosses, which diverged from the vascular plants ~450–430 million years ago, represent a unique ecological and phylogenetic group in plant evolution. Several aspects of the moss life cycle, their morphology including the presence of specialized tissue types and distinct anatomical features, gene repertoires and networks, as well as the habitat differ significantly from those of vascular plants. To evaluate the outcomes of these differences, we explore the phenotypic responses of mosses to environmental signals such as light, temperature, CO2, water, nutrients, and gravity, and compare those with what is known in vascular plants. We also outline knowledge gaps and formulate testable hypotheses based on the contribution of anatomical and molecular factors to specific phenotypic responses.
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- PAR ID:
- 10405838
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Journal of Experimental Botany
- Volume:
- 73
- Issue:
- 13
- ISSN:
- 0022-0957
- Format(s):
- Medium: X Size: p. 4514-4527
- Size(s):
- p. 4514-4527
- Sponsoring Org:
- National Science Foundation
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