Abstract
Seed morph, abiotic conditions and time of germination can affect plant fitness, but few studies have tested their combined effects on plasticity of plant life history traits. Thus, we tested the hypothesis that seed morph, germination season and watering regime influence phenotypic expression of post-germination life history traits in the diaspore-heteromorphic cold desert winter annual/spring ephemeral Diptychocarpus strictus. The two seed morphs were sown in watered and non-watered plots in late summer, and plants derived from them were watered or not-watered throughout the study. Seed morph did not affect phenology, growth and morphology, survival, dry mass accumulation and allocation or silique and seed production. Seeds in watered plots germinated in autumn (AW) and spring (SW) but only in spring for non-watered plots (SNW). A high percentage of AW, SW and SNW plants survived and reproduced, but flowering date and flowering period of autumn- vs. spring-germinated plants differed. Dry mass also differed with germination season/watering regime (AW > SW > SNW). Number of siliques and seeds increased with plant size (AW > SW > SNW), whereas percent dry mass allocated to reproduction was higher in small plants: SNW > SW > AW. Thus, although seed morph did not affect the expression of life history traits, germination season and watering regime significantly affected phenology, plant size and accumulation and allocation of biomass to reproduction. Flexibility throughout the life cycle of D. strictus is an adaptation to the variation in timing and amount of rainfall in its cold desert habitat.
Document Type
Article
Publication Date
7-11-2014
Digital Object Identifier (DOI)
http://dx.doi.org/10.1371/journal.pone.0102018
Repository Citation
Lu, Juan J.; Tan, Dun Y.; Baskin, Jerry M.; and Baskin, Carol C., "Germination Season and Watering Regime, But Not Seed Morph, Affect Life History Traits in a Cold Desert Diaspore-Heteromorphic Annual" (2014). Biology Faculty Publications. 50.
https://uknowledge.uky.edu/biology_facpub/50
Pearson correlations among characters for AW, SW and SNW plants (from upper and lower seeds of the two flower-color morphs). N = 180. *P<0.05; **P<0.001.
Notes/Citation Information
Published in PLOS One, v. 9, issue 7, e102018.
© 2014 Lu et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.