Carbon dioxide exchange of lettuce plants under hypobaric conditions

Mathematics – Logic

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

5

Scientific paper

Growth of plants in a Controlled Ecological Life Support System (CELSS) may involve the use of hypobaric pressures enabling lower mass requirements for atmospheres and possible enhancement of crop productivity. A controlled environment plant growth chamber with hypobaric capability designed and built at Ames Research Center was used to determine if reduced pressures influence the rates of photosynthesis (Ps) and dark respiration (DR) of hydroponically grown lettuce plants. The chamber, referred to as a plant volatiles chamber (PVC), has a growing area of about 0.2 m^2, a total gas volume of about 0.7 m^3, and a leak rate at 50 kPa of < 0.1%/day. When the pressure in the chamber was reduced from ambient to 51 kPa, the rate of net Ps increased by 25% and the rate of DR decreased by 40%. The rate of Ps increased linearly with decreasing pressure. There was a greater effect of reduced pressure at 41 Pa CO_2 than at 81 Pa CO_2. This is consistent with reports showing greater inhibition of photorespiration (Pr) in reduced O_2 at low CO_2 concentrations. When the partial pressure of O_2 was held constant but the total pressure was varied between 51 and 101 kPa, the rate of CO_2 uptake was nearly constant, suggesting that low pressure enhancement of Ps may be mainly attributable to lowered partial pressure of O_2 and the accompanying reduction in Pr. The effects of lowered partial pressure of O_2 on Ps and DR could result in substantial increases in the rates of biomass production, enabling rapid throughput of crops or allowing flexibility in the use of mass and energy resources for a CELSS.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Carbon dioxide exchange of lettuce plants under hypobaric conditions does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Carbon dioxide exchange of lettuce plants under hypobaric conditions, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Carbon dioxide exchange of lettuce plants under hypobaric conditions will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-967969

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.