Skip to main content

Free Content Effects of Labyrinthula Infection on the Photosynthetic Capacity of Thalassia Testudinum

Download Article:
(PDF 366.60546875 kb)
Blackened, necrotic lesions on Thalassia testudinum leaves are frequently associated with seagrass die-off in Florida Bay. A previously undescribed species of the marine slime mold, genus Labyrinthula, is the primary causal agent of these lesions. When Labyrinthula infection was present, variations in lesion coverage resulted in significant differences in dry-weight based photosynthesis versus irradiance (P/I) responses of Thalassia leaf tissue, reducing photosynthetic capacity and oxygen output. Maximum photosynthetic rate, Pmax' decreased to below zero when lesions covered 25% or more of the leaf tissue. In addition, respiration rates in infected leaves were up to three times greater than in adjacent, un infected tissue. Alpha (α), the initial slope of the P/I relationship, exhibited little change with low lesion coverage but was usually reduced with higher lesion coverage. These results show that the presence of Labyrinthula lesions impair photosynthesis of Thalassia leaf tissues and might reduce oxygen available for transport to belowground tissues, possibly making Thalassia more susceptible to hypoxia and sulfide toxicity.

7 References.

No Supplementary Data.
No Data/Media
No Metrics

Document Type: Research Article

Publication date: 1994-05-01

More about this publication?
  • The Bulletin of Marine Science is dedicated to the dissemination of high quality research from the world's oceans. All aspects of marine science are treated by the Bulletin of Marine Science, including papers in marine biology, biological oceanography, fisheries, marine affairs, applied marine physics, marine geology and geophysics, marine and atmospheric chemistry, and meteorology and physical oceanography.
  • Editorial Board
  • Information for Authors
  • Subscribe to this Title
  • Terms & Conditions
  • Ingenta Connect is not responsible for the content or availability of external websites
  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more