Symbioses: Plant, Animal, and Microbe Interactions
Cannon, Brandi , Garrison, Jessica , Sopas, James , Verastegui, Timothy , Randle, Christopher .
Presentation, aroma, and flavor: Investigation of host cues in the orientation and establishment of Phoradendron serotinum (Viscaceae).
Obligate parasitic plants cannot survive without the influx of water and/or nutrients from host plants. Therefore, successful establishment of haustoria (vascular organs of penetration and transport) is necessary for the survival of an emerging seedling. Extensive studies have been performed on the effect of host cues on germination, orientation, and development of haustoria in root parasites. For root parasites, host cues must be transmitted through the rhizosphere and are largely chemical. Plants that are parasitic on the aboveground stems of host plants must be able to detect hosts in a much different milieu. Phoradendron serotinum (leafy mistletoe) is a water parasite of broadleaf trees. While P. serotinum parasitizes many different hosts across its range, populations are most often locally host specific, preferring a single host even when other hosts are available. The underlying cause of this pattern of host preference is unknown, and will remain so until host cues responsible for successful establishment of haustoria have been identified. In this study, we examined the effects of light cues, physiochemical cues associated with the host surface, and gaseous chemical cues on the viability, orientation, and successful establishment of emerging haustoria on host plants. Light and physiochemical cues associated with the host substrate had a significant effect on haustorial establishment. Gaseous cues had a significant positive effect on viability and orientation. This latter result was foreshadowed by a similar finding in the stem parasite Cuscuta, which responds to gaseous cues emitted by host plants.
Log in to add this item to your schedule
1 - Sam Houston State University, Department of Biological Sciences, 1900 Avenue I, Huntsville, TX, 77340, USA
Presentation Type: Oral Paper:Papers for Topics
Location: Portland Room/Chase Park Plaza
Date: Tuesday, July 12th, 2011
Time: 4:15 PM