DOI: 10.5061/dryad.nb675
title: Data from: Blossom colour change after pollination provides carbon for developing seeds

description: 1. We tested the hypothesis that greening of the floral (involucral)
 bracts of Dalechampia scandens blossoms after pollination (when bracts are
 white) increases carbon assimilation and provides photosynthate to
 developing seeds. 2. We investigated the importance of the involucral
 bracts for the process of seed development in two ways. First, we removed
 or shaded bracts of hand-pollinated blossoms to prevent their
 photosynthesis and tested the effects of these manipulations on seed
 development. Secondly, we measured the photosynthetic rate of blossoms
 with white vs. green bracts and compared these rates with those of leaves.
 3. After four weeks of development, seeds from blossoms with bracts
 removed or shaded were lighter than those produced by unmanipulated
 blossoms. Furthermore, although the area-based photosynthetic rate of
 green bracts was much lower than that of leaves, it was much greater than
 that of white bracts. Estimates of the daily carbon budget based on these
 measurements indicate that photosynthesis in green bracts is sufficient to
 meet the respiratory demand of the whole blossom, but not so in white
 bracts. 4. Our results support the hypothesis that colour change in D.
 scandens bracts allows carbon assimilation that contributes to the carbon
 demand of nearby developing seeds.
description: Data from the experiment
 where the effect of bract manipulation on seed mass of hand-pollinated
 blossoms was investigated.FemaleID: identity code
 of the maternal plant MaleID: identity code of the paternal plant ped1:
 peduncle diameter first measurement ped2: peduncle diameter second
 measurement poll: pollination date crossID: identity code for the cross
 (equivalent to a unique blossom identity code) treatcode: code for the
 treatment: cut = bracts removed; cutcont= control for the cutting
 experiment; bag = blossom shaded; cont = non-manipulated control harvest:
 date harvesting seedID: identity number for each seed within each blossom
 seedset : blossom seed set seedmass: mass of individual seeds in mg
 date.weight: seed weight measuring date ped: average of the two
 measurements of the peduncle diameter time: maturation time in days
 (harvesting date – pollination date)Pelabon et al FE file
 1.txtMeasurements of gas
 exchange in Dalechampia scandensPlant_ID: Identity of
 the plants Color: green = blossom with green bracts; white = blossom with
 white bract; leaf = leaf Replicate: replicate identity. Together with the
 plant_ID this provides a single ID number for each blossom analyzed.
 Bract: No_Bract = measurements with bracts removed; Bract = measurement
 with blossom intact; leaf = measurements on leaf. AN: gas exchange in the
 light (carbon assimilation) Area_Leaf: area of the structure from which
 gaze exchange is measured. For the blossom with bract removed this is a
 rough measurement of the fruits area (not used in the analysis). R: gas
 exchange in the dark (respiration – negative value) = R GPP: Gross
 photosynthetic rate = AN – R GPPnett: Gross photosynthetic rate: this
 correspond to the GPP of the blossom with the bracts minus the GPP of the
 blossom with the bract removed. This is why this value is given only for
 the rows where the value for the bract column is “Bract” or
 “Leaf”Pelabon et al FE file
 2.txt