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The study of moss calyptra form and function began almost 250 years ago, but calyptra research has remained a niche endeavor focusing on only a small number of species. Recent advances have focused on calyptra cuticular waxes, which function in dehydration protection of the immature sporophyte apex. The physical presence of the calyptra also plays a role in sporophyte development, potentially via its influence on auxin transport. Progress developing genomic resources for mosses beyond the model Physcomitrium patens, specifically for species with larger calyptrae and taller sporophytes, in combination with advances in CRISPR-Cas9 genome editing will enable the influence of the calyptra on gene expression and the production of RNAs and proteins that coordinate sporophyte development to be explored.
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Moss Sporophytes with a Higher Proportion of Leptoids Have Higher Water Transport Rates
The sporophytes of moss plants are dependent on the gametophytes for both photosynthesis and water, which makes conducting cells (hydroids and leptoids) an important part of the sporophyte anatomy. A previous study found that Physcomitrium pyriforme, which has shorter sporophytes, had higher rates of water transport than Funaria hygrometrica, which has taller sporophytes. The aim of this study is to test for differences in the conducting cell anatomy between these two moss species, which could be responsible for differences in water transport rates. We used histology methods to fix, embed, and section sporophyte seta and then quantified the numbers and sizes of the conducting cells. The results revealed that leptoids comprise a higher proportion of the conducting cell area in P. pyriforme, while hydroids comprise more of the conducting cell area in F. hygrometrica. These results point toward the leptoids playing a role in water transport in the moss sporophyte.
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- Award ID(s):
- 2046467
- PAR ID:
- 10569941
- Publisher / Repository:
- American Bryological and Lichenological Society
- Date Published:
- Journal Name:
- Evansia
- Volume:
- 41
- Issue:
- 3
- ISSN:
- 0747-9859
- Page Range / eLocation ID:
- 67-71
- Subject(s) / Keyword(s):
- Anatomy Bryophytes conducting cells hydroids seta
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1639/0747-9859-41.3.67
