DOI: 10.5061/dryad.503nd
title: Data from: Transgenerational effects of extreme weather: perennial plant offspring show modified germination, growth and stoichiometry

description: 1) Climate change is predicted to increase the frequency and magnitude of
 extreme climatic events. These changes will directly affect plant
 individuals and populations and thus modify plant community composition.
 Little is known, however, about transgenerational effects (i.e. the
 influence of the parental environment on offspring phenotype and
 performance beyond the effects of transmitted genes) of climate extremes
 and community composition. Perennial plants have been particularly
 neglected. This impedes projections on species adaptations and population
 dynamics under climate change. 2) Maternal plants of two widespread
 dwarf-shrub species (Genista tinctoria and Calluna vulgaris) recurrently
 experienced extreme weather event manipulations each year (drought and
 heavy rain). To test for transgenerational effects of community
 composition, C. vulgaris maternal plants were grown in communities
 differing in the number of neighbouring species. After six years, seeds of
 maternal plants were collected at least 2 month after the final weather
 treatments. We assessed transgenerational effects of the extreme events
 and of altered community composition on germination and monitored the
 development of offspring over two years. 3) We show that extreme events
 experienced by maternal plants influence offspring germination and growth
 beyond the seedling stage. Seeds produced by maternal plants experiencing
 stress, indicated by increased tissue die-back, germinated earlier in both
 observed species. We observed differences in leaf stoichiometry and growth
 rates for G. tinctoria offspring throughout the first year: Offspring from
 heavy rain-treated mothers showed reduced leaf C:N ratio and higher growth
 rates. Results further indicate that not only community density, as
 investigated in prior studies, but also community composition trigger
 transgenerational effects. 4) Synthesis: Our findings show that variation
 in the maternal environment not only affects number, but also performance
 of offspring. Extreme climatic events, terminated before seed set, induce
 transgenerational effects. Species richness of mother communities can
 affect the stress level of target species and thereby germination
 regardless of community density. In contrast to prior studies, which
 revealed direct effects of chronic stress on plant individuals, this study
 emphasizes the importance of addressing transgenerational effects of
 extreme weather events when projecting future ecological responses and
 adaptation to climate change.
description: Effects of extreme
 weather and community composition on mothers and their
 offspringIn each sheet, one
 response variable (marked in yellow) is presented. Maternal treatments
 means the weather extremes the mothers were exposed to (drought event,
 heavy rain spell or ambient conditions (control)). Calluna vulgaris
 mothers were also growing in two- vs. four species communities. Block
 means the weather manipulations blocks in which the two different
 community compositions were nested. The first four sheets refer to
 maternal data in the years 2005-2010, the other sheets to offspring data,
 assessed from 2011-2012.WalterHarterTransgenerationalEffectsClimateExtremesAllResultsJEcol.xlsx