Data from: Impacts of soil nitrogen and phosphorus levels on cytotype performance of the circumboreal herb, Chamerion angustifolium: implications for polyploid establishment

Although polyploidy commonly occurs in angiosperms, not all
polyploidization events lead to successful lineages, and environmental
conditions could influence cytotype dynamics and polyploid success. Low
soil nitrogen and/or phosphorus concentrations often limit ecosystem
primary productivity, and changes in these nutrients might differentially
favor some cytotypes over others, thereby influencing polyploid
establishment. We grew diploid, established tetraploid, and neotetraploid
Chamerion angustifolium (fireweed) in a greenhouse under low and high soil
nitrogen and phosphorus conditions and different competition treatments
and measured plant performance (height, biomass, flower and root-bud
production) and insect damage responses. By comparing neotetraploids to
established tetraploids, we were able to examine traits and responses that
might directly arise from polyploidization before they are modified by
natural selection and/or genetic drift. We found that (1) neopolyploids
were the least likely to survive and flower and experienced the most
herbivore damage regardless of nutrient conditions; (2) both neo- and
established tetraploids had greater biomass and root-bud production under
nutrient enriched conditions, whereas diploid biomass and root bud
production was not significantly affected by nutrients; (3) intra-cytotype
competition more negatively affected diploids and established tetraploids
than it did neotetraploids. Following polyploidization, biomass and clonal
growth might be more immediately affected by environmental nutrient
availabilities than plant survival, flowering, and/or responses to
herbivory, which could influence competitive dynamics. Specifically,
polyploids might have competitive and colonizing advantages over diploids
under nutrient enriched conditions favoring their establishment, although
establishment may also depend upon the density and occurrences of other
related cytotypes in a population.