Eilts, J. Alexander .
An early look at the transport of mineral resources inthe clonal forb Fragaria vesca L.
The movement of resources within plants is critical to their growth, competition and herbivore responses. In clonal plants the movement of resources between ramets can facilitate the persistence of ramets and whole clones in otherwise unfavorable conditions. Though this movement or sharing of resources between ramets has been shown to provide numerous benefits for survival, little is known about which tissues act as the pathways of long distance transport under varying resource availabilities. To better understand the responses in resource sharing between ramets I have made a preliminary exploration of the tissues through which mineral resources are transported in the clonal forb Fragaria vesca. I conducted two experiments to address whether xylem or phloem predominates in inter-ramet movement of mineral resources. The first experiment measured gas exchange in two-ramet, clonal fragments under varying experimental resource availabilities seeking a signal of water transport regulation. The second experiment utilized a radio isotope of phosphorus to examine phosphorus uptake and retention in two-ramet, clonal fragments under manipulated resource availability conditions in addition to a phloem girdling treatment applied to the connecting stolon.
Contrary to expectations, transpiration was greatest in ramets receiving fertilizer connected to an unfertilized partner. The specific activity from the radio isotope of phosphorus was higher only in the unfertilized, labeled ramets with the girdling treatment applied suggesting accumulation was reduced when phloem could act to export the phosphorus. Though both experiments are preliminary in their findings, they suggest that phloem, not xylem, dominates as the transport tissue for mineral resource sharing in this species. This finding contradicts preconceived expectations about resource sharing in clonal plants. The implications of phloem versus xylem transport of mineral resources in clonal plants will be discussed along with future directions of this work.
Log in to add this item to your schedule
1 - University Of Minnesota, Ecology, Evolution & Behavior, 1987 Upper Buford Circle, 100 Ecology, St. Paul, MN, 55108, USA
Presentation Type: Oral Paper:Papers for Topics
Location: Forsyth Room/Chase Park Plaza
Date: Monday, July 11th, 2011
Time: 3:20 PM