Desiccation tolerance has evolved recurrently across diverse land plant lineages as an adaptation for survival in regions where seasonal rainfall drives periodic drying of vegetative tissues. Growing interest in this phenomenon has fueled recent physiological, biochemical, and genomic insights into the mechanistic basis of desiccation tolerance. Although, desiccation tolerance is often viewed as binary and monolithic, substantial variation exists in the phenotype and underlying mechanisms across diverse lineages, heterogeneous populations, and throughout the development of individual plants. Most studies have focused on conserved responses in a subset desiccation-tolerant plants under laboratory conditions. Consequently, the variability and natural diversity of desiccation-tolerantmore »
This content will become publicly available on May 1, 2023
Variability in Functional Traits along an Environmental Gradient in the South African Resurrection Plant Myrothamnus flabellifolia
Many desiccation-tolerant plants are widely distributed and exposed to substantial environmental variation across their native range. These environmental differences generate site-specific selective pressures that could drive natural variation in desiccation tolerance across populations. If identified, such natural variation can be used to target tolerance-enhancing characteristics and identify trait associations within a common genetic background. Here, we tested for natural variation in desiccation tolerance across wild populations of the South African resurrection plant Myrothamnus flabellifolia. We surveyed a suite of functional traits related to desiccation tolerance, leaf economics, and reproductive allocation in M. flabellifolia to test for trait associations and tradeoffs. Despite considerable environmental variation across the study area, M. flabellifolia plants were extremely desiccation tolerant at all sites, suggesting that tolerance is either maintained by selection or fixed in these populations. However, we detected notable associations between environmental variation, population characteristics, and fitness traits. Relative to mesic sites, plants in xeric sites were more abundant and larger, but were slower growing and less reproductive. The negative association between growth and reproduction with plant size and abundance pointed towards a potential growth–abundance tradeoff. The finding that M. flabellifolia is more common in xeric sites despite reductions in growth rate and reproduction more »
- Award ID(s):
- 1906094
- Publication Date:
- NSF-PAR ID:
- 10332279
- Journal Name:
- Plants
- Volume:
- 11
- Issue:
- 10
- Page Range or eLocation-ID:
- 1332
- ISSN:
- 2223-7747
- Sponsoring Org:
- National Science Foundation
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