Skip to page content
USDA Forest Service
  
Treesearch

Research & Development Treesearch

 
Treesearch Home
About Treesearch
Contact Us
Research & Development
Forest Products Lab
International Institute of Tropical Forestry
Northern
Pacific Northwest
Pacific Southwest
Rocky Mountain
Southern Research Station
Help
 

Science.gov - We Participate


USA.gov  Government Made Easy


Global Forest Information Service

US Forest Service
P.O. Box 96090
Washington, D.C.
20090-6090

(202) 205-8333

You are here: Home / Search / Publication Information
Bookmark and Share

Publication Information

View PDF (139 KB bytes)

Title: Composition of root pressure exudate from conifers.

Author: Ketchie, D.O.; Lopushinsky, W.;

Date: 1981

Source: Res. Note PNW-RN-395. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station. 6 p

Publication Series: Research Note (RN)

Description: Root pressure exudates collected from detopped seedlings of Douglas-fir, grand fir, noble fir, Pacific silver fir, ponderosa pine, lodgepole pine, and Engelmann spruce were analyzed for sugars, amino acids, organic acids, nitrogen, potassium, calcium, and magnesium. Sugar concentrations ranged from 0.10 percent to 5 percent, and included glucose, sucrose, fructose, and two unknowns, possibly rhamnose, and ribose. Amino acid concentrations ranged from 0.02 to 0.10 percent, and organic acids from 0.01 to 0.06 percent. Aspartic acid, glutamic acid and glutamine were the main amino acids in the exudates of all species with lesser amounts of glycine, serine, asparagine, arginine, leucine, and alanine. Nitrogen concentrations ranged from 0.005 to 0.012 percent, potassium from 0.006 to 0.018 percent, and calcium from 0.001 to 0.005 percent. Magnesium concentration was 0.001 percent in all species. The pH of the exudates ranged from 5.3 to 5.7. Except for the relatively high concentrations of sugar in the exudates from grand fir and noble fir, there were no species-related differences in amounts of the various constituents.

Keywords: Exudation, root exudates

Publication Notes:

  • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
  • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
  • You may send email to pnw_pnwpubs@fs.fed.us to request a hard copy of this publication. (Please specify exactly which publication you are requesting and your mailing address.)

XML: View XML

Citation:


Ketchie, D.O.; Lopushinsky, W. 1981. Composition of root pressure exudate from conifers. Res. Note PNW-RN-395. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station. 6 p

 


 [ Get Acrobat ]  Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility

USDA logo which links to the department's national site. Forest Service logo which links to the agency's national site.