NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Effect of CO2 levels on nutrient content of lettuce and radishAtmospheric carbon-dioxide enrichment is known to affect the yield of lettuce and radish grown in controlled environments, but little is known about CO2 enrichment effects on the chemical composition of lettuce and radish. These crops are useful model systems for a Controlled Ecological Life-Support System (CELSS), largely because of their relatively short production cycles. Lettuce (Lactuca sativa L.) cultivar 'Waldmann's Green' and radish (Raphanus sativus L.) cultivar 'Giant White Globe' were grown both in the field and in controlled environments, where hydroponic nutrient solution, light, and temperature were regulated, and where CO2 levels were controlled at 400, 1000, 5000, or 10,000 ppm. Plants were harvested at maturity, dried, and analyzed for proximate composition (protein, fat, ash, and carbohydrate), total nitrogen (N), nitrate N, free sugars, starch, total dietary fiber, and minerals. Total N, protein N, nonprotein N (NPN), and nitrate N generally increased for radish roots and lettuce leaves when grown under growth chamber conditions compared to field conditions. The nitrate-N level of lettuce leaves, as a percentage of total NPN, decreased with increasing levels of CO2 enrichment. The ash content of radish roots and of radish and lettuce leaves decreased with increasing levels of CO2 enrichment. The levels of certain minerals differed between field- and chamber-grown materials, including changes in the calcium (Ca) and phosphorus (P) contents of radish and lettuce leaves, resulting in reduced Ca/P ratio for chamber-grown materials. The free-sugar contents were similar between the field and chamber-grown lettuce leaves, but total dietary fiber content was much higher in the field-grown plant material. The starch content of growth-chamber lettuce increased with CO2 level.
Document ID
20040089940
Acquisition Source
Headquarters
Document Type
Reprint (Version printed in journal)
Authors
McKeehen, J. D.
(NASA Headquarters Washington, DC United States)
Smart, D. J.
Mackowiak, C. L.
Wheeler, R. M.
Nielsen, S. S.
Mitchell, C. A.
Date Acquired
August 21, 2013
Publication Date
January 1, 1996
Publication Information
Publication: Advances in space research : the official journal of the Committee on Space Research (COSPAR)
Volume: 18
Issue: 5-Apr
Subject Category
Man/System Technology And Life Support
Funding Number(s)
CONTRACT_GRANT: NAGW-2329
Distribution Limits
Public
Copyright
Other
Keywords
NASA Discipline Life Support Systems
NASA Program CELSS
Non-NASA Center
NASA Discipline Number 93-10
NASA Discipline Number 61-20
NASA Program NSCORT
NASA Center KSC

Available Downloads

There are no available downloads for this record.
No Preview Available