Plants require water and nutrients for survival, although the effects of their availabilities on plant fitness differ amongst species. Genome size variation, within and across species, is suspected to influence plant water and nutrient requirements, but little is known about how variations in these resources concurrently affect plant fitness based on genome size. We examined how genome size variation between autopolyploid cytotypes influences plant morphological and physiological traits, and whether cytotype‐specific trait responses differ based on water and/or nutrient availability. Diploid and autotetraploid Resource availabilities and cytotype identity influenced some plant responses but their effects were independent of each other. Plants grown in high‐water and nutrient treatments were larger, plants grown in low‐water or high‐nutrient treatments had higher Nutrient and water availability could influence intra‐ and interspecific competitive outcomes. Although
Xylem anatomy and function have large implications for plant growth as well as survival during drought, but the impact of nutrient limitation on xylem is not fully understood. This study examines the pygmy forest in California, a plant community that experiences negligible water stress but is severely stunted by low‐nutrient and acidic soil, to investigate how nutrient limitation affects xylem function. Thirteen key anatomical and hydraulic traits of stems of four species were compared between pygmy forest plants and nearby conspecifics growing on richer soil. Resistance to cavitation (P50), a critical trait for predicting survival during drought, had highly species‐specific responses: in one species, pygmy plants had a 26% decrease in cavitation resistance compared to higher‐nutrient conspecifics, while in another species, pygmy plants had a 56% increase in cavitation resistance. Other traits responded to nutrient limitation more consistently: pygmy plants had smaller xylem conduits and higher leaf‐specific conductivity ( Edaphic stress, even in the absence of water stress, altered xylem structure and thus had substantial impacts on water transport. Importantly, nutrient limitation shifted cavitation resistance in a species‐specific and unpredictable manner; this finding has implications for the assessment of cavitation resistance in other natural systems.
- PAR ID:
- 10458264
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 226
- Issue:
- 3
- ISSN:
- 0028-646X
- Page Range / eLocation ID:
- p. 760-769
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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