Germination and growth of wheat in simulated Martian atmospheres

The Interplanetary Exchange of Photosynthesis

“…Within the first few days of germination most plant seeds are net oxygen consumers and thus landing on an anoxic planet would prevent seed germination. Wheat seeds were unable to germinate in simulated Martian atmospheres (Schwartzkopf and Mancinelli 1991). Thus, for seeds to survive and grow, they likely require the presence of oxygenic photosynthesis in the first place.…”

Plants survive rapid decompression: Implications for bioregenerative life support

“…Plants have been studied at very low pressures before, including several studies as low as 10 kPa (Goto et al, 1996;Massimino and Andre, 1999;Paul et al, 2004;Richards et al, 2006), one study at 7 kPa (Andre and Richaud, 1986), and one attempt to germinate and grow wheat seeds at 1 kPa in a simulated Martian atmosphere (Schwartzkopf and Mancinelli, 1991), which was unsuccessful unless 6 kPa of O 2 was added to the atmosphere. To our knowledge, there have been no studies of plant responses to rapid decompression, although there is literature on the psychrometric events and settings for rapid vacuum cooling of vegetables and fruits (Erickson and Garrett, 1981;Thompson et al, 1998).…”

Ethylene reduces plant gas exchange and growth of lettuce grown from seed to harvest under hypobaric and ambient total pressure

“…Growth of lettuce seedlings 14-days after germination under hypobaric (25/12 kPa pO2) and ambient total pressure (101/21, 101/12 kPa pO2) with ethylene scrubbed or accumulated in chambers, n = 4. another study, hypobaria (21-24 kPa) did not inhibit seed germination and initial growth as long as pO 2 was 5 kPa or more (Musgrave et al, 1998). Schwartzkopf and Mancinelli (1991) reported that seedlings germinated and grew during a week-long study at 6 kPa total gas pressure, provided the atmosphere was comprised predominately of oxygen (pO 2 = 5 kPa; ∼83% O 2 ); but at lower total pressures and therefore less O 2 , seeds failed to germinate. There are likely species differences in response to hypobaria and hypoxia, i.e., lettuce is more sensitive to hypoxia than wheat (He et al, 2003).…”

“…A major potential limitation to plant growth under hypobaria is if the partial pressure of O 2 (pO 2 ) is reduced, oxidative phosphorylation can become limited (Drew, 1997). Seedlings germinated and grew during a week-long study at 6 kPa total gas pressure, provided the atmosphere was comprised predominately of oxygen (pO 2 = 5 kPa; ∼83% O 2 ); but at lower total pressures and therefore less O 2 , seeds failed to germinate (Schwartzkopf and Mancinelli, 1991). Low total pressure (21-24 kPa) did not inhibit seed germination and initial growth as long as pO 2 was 5 kPa or more (Musgrave et al, 1998).…”