Data from: Blossom colour change after pollination provides carbon for developing seeds

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.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.tx