DOI: 10.5061/dryad.n75dt
title: Data from: Fitness of crop-wild hybrid sunflowers under competitive conditions: implications for crop-to-wild introgression

description: Understanding the likelihood and extent of introgression of novel alleles
 in hybrid zones requires comparison of lifetime fitness of parents and
 hybrid progeny. However, fitness differences among cross types can vary
 depending on biotic conditions, thereby influencing introgression
 patterns. Based on past work, we predicted that increased competition
 would enhance introgression between cultivated and wild sunflower
 (Helianthus annuus) by reducing fitness advantages of wild plants. To test
 this prediction, we established a factorial field experiment in Kansas,
 USA where we monitored the fitness of four cross types (Wild, F1, F2, and
 BCw hybrids) under different levels of interspecific and intraspecific
 competition. Intraspecific manipulations consisted both of density of
 competitors and of frequency of crop-wild hybrids. We recorded emergence
 of overwintered seeds, survival to reproduction, and numbers of seeds
 produced per reproductive plant. We also calculated two compound fitness
 measures: seeds produced per emerged seedling and seeds produced per
 planted seed. Cross type and intraspecific competition affected emergence
 and survival to reproduction, respectively. Further, cross type interacted
 with competitive treatments to influence all other fitness traits. More
 intense competition treatments, especially related to density of
 intraspecific competitors, repeatedly reduced the fitness advantage of
 wild plants when considering seeds produced per reproductive plant and per
 emerged seedling, and F2 plants often became indistinguishable from the
 wilds. Wild fitness remained superior when seedling emergence was also
 considered as part of fitness, but the fitness of F2 hybrids relative to
 wild plants more than quadrupled with the addition of interspecific
 competitors and high densities of intraspecific competitors. Meanwhile,
 contrary to prediction, lower hybrid frequency reduced wild fitness
 advantage. These results emphasize the importance of taking a full life
 cycle perspective. Additionally, due to effects of exogenous selection, a
 given hybrid generation may be especially well-suited to hastening
 introgression under particular environmental conditions.
description: Mercer et al PLOS ONE
 Data for analyses of values from individualsThis file has four tabs
 which provide the data necessary to (1) recreate the analyses on the life
 stages (emergence and survival to reproduction) as well as (2) provide the
 basis for the seed production per plant data, which is actually analyzed
 at the level of the plot (see associated data set). For this latter
 purpose, data from the "Seeds per head" tab can be used to
 recreate the seed estimates per head, which can were then used on the
 "For estimates of seeds per plt" tab to calculate seeds per
 plant. The seeds per plant tab data is the basis for the averages by plot.
 Metadata tab and the paper for more information about the variables and
 analyses.Mercer et al PLOS ONE
 Individual data set for
 Dryad.xlsMercer et al. PLOS ONE
 Data for analyses of fitness variablesThis dataset allows you
 to recreate the analyses of seeds produced per reproductive plant, per
 emerged seedling, and per planted seed.Mercer et al. PLOS ONE Plot
 level data for Dryad.xlsMercer et al PLOS ONE
 Environmental treatments response dataThis file has three tabs
 of data that help you recreate the analyses assessing whether our
 environmental treatments manipulated the biotic environment as
 expected.