Abstract
Species responses to climate change will be primarily driven by their environmental tolerance range, or niche breadth, with the expectation that broad niches will increase resilience. Niche breadth is expected to be larger in more heterogeneous environments and moderated by life history. Niche breadth also varies across life stages. Therefore, the life stage with the narrowest niche may serve as the best predictor of climatic vulnerability. To investigate the relationship between niche breadth, climate and life stage we identify germination niche breadth for dormant and non-dormant seeds in multiple populations of three milkweed (Asclepias) species. Complementary trials evaluated germination under conditions simulating historic and predicted future climate by varying cold–moist stratification temperature, length and incubation temperature. Germination niche breadth was derived from germination evenness across treatments (Levins B n ), with stratified seeds considered less dormant than non-stratified seeds. Germination response varies significantly among species, populations and treatments. Cold–moist stratification ≥4 weeks (1–3 °C) followed by incubation at 25/15 °C+ achieves peak germination for most populations. Germination niche breadth significantly expands following stratification and interacts significantly with latitude of origin. Interestingly, two species display a positive relationship between niche breadth and latitude, while the third presents a concave quadratic relationship. Germination niche breadth significantly varies by species, latitude and population, suggesting an interaction between source climate, life history and site-specific factors. Results contribute to our understanding of inter- and intraspecific variation in germination, underscore the role of dormancy in germination niche breadth, and have implications for prioritising and conserving species under climate change.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 425-438 |
| Number of pages | 14 |
| Journal | Plant Biology |
| Volume | 21 |
| Issue number | 3 |
| DOIs | |
| State | Published - May 1 2019 |
| Externally published | Yes |
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Keywords
- Environmental heterogeneity
- intraspecific variability
- latitude-niche breadth hypothesis
- milkweed
- physiological dormancy
- population variation
- seed germination
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Plant Science
Cite this
}
Germination niche breadth varies inconsistently among three Asclepias congeners along a latitudinal gradient. / Finch, J.; Walck, J. L.; Hidayati, S. N.; Kramer, Andrea L T; Lason, V.; Havens, Kayri.
In: Plant Biology, Vol. 21, No. 3, 01.05.2019, p. 425-438.Research output: Contribution to journal › Article
TY - JOUR
T1 - Germination niche breadth varies inconsistently among three Asclepias congeners along a latitudinal gradient
AU - Finch, J.
AU - Walck, J. L.
AU - Hidayati, S. N.
AU - Kramer, Andrea L T
AU - Lason, V.
AU - Havens, Kayri
PY - 2019/5/1
Y1 - 2019/5/1
N2 - Species responses to climate change will be primarily driven by their environmental tolerance range, or niche breadth, with the expectation that broad niches will increase resilience. Niche breadth is expected to be larger in more heterogeneous environments and moderated by life history. Niche breadth also varies across life stages. Therefore, the life stage with the narrowest niche may serve as the best predictor of climatic vulnerability. To investigate the relationship between niche breadth, climate and life stage we identify germination niche breadth for dormant and non-dormant seeds in multiple populations of three milkweed (Asclepias) species. Complementary trials evaluated germination under conditions simulating historic and predicted future climate by varying cold–moist stratification temperature, length and incubation temperature. Germination niche breadth was derived from germination evenness across treatments (Levins B n ), with stratified seeds considered less dormant than non-stratified seeds. Germination response varies significantly among species, populations and treatments. Cold–moist stratification ≥4 weeks (1–3 °C) followed by incubation at 25/15 °C+ achieves peak germination for most populations. Germination niche breadth significantly expands following stratification and interacts significantly with latitude of origin. Interestingly, two species display a positive relationship between niche breadth and latitude, while the third presents a concave quadratic relationship. Germination niche breadth significantly varies by species, latitude and population, suggesting an interaction between source climate, life history and site-specific factors. Results contribute to our understanding of inter- and intraspecific variation in germination, underscore the role of dormancy in germination niche breadth, and have implications for prioritising and conserving species under climate change.
AB - Species responses to climate change will be primarily driven by their environmental tolerance range, or niche breadth, with the expectation that broad niches will increase resilience. Niche breadth is expected to be larger in more heterogeneous environments and moderated by life history. Niche breadth also varies across life stages. Therefore, the life stage with the narrowest niche may serve as the best predictor of climatic vulnerability. To investigate the relationship between niche breadth, climate and life stage we identify germination niche breadth for dormant and non-dormant seeds in multiple populations of three milkweed (Asclepias) species. Complementary trials evaluated germination under conditions simulating historic and predicted future climate by varying cold–moist stratification temperature, length and incubation temperature. Germination niche breadth was derived from germination evenness across treatments (Levins B n ), with stratified seeds considered less dormant than non-stratified seeds. Germination response varies significantly among species, populations and treatments. Cold–moist stratification ≥4 weeks (1–3 °C) followed by incubation at 25/15 °C+ achieves peak germination for most populations. Germination niche breadth significantly expands following stratification and interacts significantly with latitude of origin. Interestingly, two species display a positive relationship between niche breadth and latitude, while the third presents a concave quadratic relationship. Germination niche breadth significantly varies by species, latitude and population, suggesting an interaction between source climate, life history and site-specific factors. Results contribute to our understanding of inter- and intraspecific variation in germination, underscore the role of dormancy in germination niche breadth, and have implications for prioritising and conserving species under climate change.
KW - Environmental heterogeneity
KW - intraspecific variability
KW - latitude-niche breadth hypothesis
KW - milkweed
KW - physiological dormancy
KW - population variation
KW - seed germination
UR - http://www.scopus.com/inward/record.url?scp=85052790280&partnerID=8YFLogxK
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U2 - 10.1111/plb.12843
DO - 10.1111/plb.12843
M3 - Article
VL - 21
SP - 425
EP - 438
JO - Acta Botanica Neerlandica
JF - Acta Botanica Neerlandica
SN - 1435-8603
IS - 3
ER -