Expedition 31 Flight Engineer Don Pettit writes about plant sprouts and deaths in the space zucchini's diary in his latest blog entry.
http://go.usa.gov/vAG June 9-13 - Diary of a Space Zucchini
June 9
Great news; I have a baby brother sprout! Gardener just showed me baby Zuc. He is strong and healthy and ready to move from the sprouter into his own aeroponic bag. While Broccoli and Sunflower are great companions, there is nothing quite like having a zucchini to zucchini conversation.
June 10
Baby Zuc has developed his hull spreader! We have tough seed pods and sometimes they do not split in half like they should thus trapping the cotyledons inside and causing the sprout to die. We have a special bump on our stem that catches on our seed pod and spreads the hulls open so the new leaves can emerge undamaged. Previous ideas on this required gravity to direct our stem to grow this bump but we seem to be able to do this without a gravitational signal. On the frontier, even a baby sprout can teach us something new.
June 11
Gardener has been busy. We have a new Sunflower sprout. Sunflower is elated and can hardly wait to show Sprout his blossom.
June 12
A great sadness has taken us all; Sunflower sprout died. He became weak and his cotyledons could not emerge from the hull. Gardener performed surgery and carefully removed the hull but it was too late. We returned sprout to the compost from whence he came. I guess we are all made out of recyclable materials.
June 13
One of our machines that removes carbon dioxide from the air failed last night and the carbon dioxide is now at nearly half a percent. The animal part of our crew breathes in oxygen and gives off carbon dioxide. The current level is enough to give animals stuffy noses and headaches but for us plants, this is like being in a sweet greenhouse. On Earth the atmosphere is about 0.04 percent. Broccoli, Sunflower and I are doing all we can to breath in the carbon dioxide and exhale oxygen. Even the algae are doing their part. I would say these stowaways have now become part of the crew. I find it interesting how plants and animals complement each other. Meanwhile, Gardener is working on fixing the machine. He has wires and tweezers and a big head lamp. His head remained buried inside the machine for quite some time before he came out. He said it was a bad temperature sensor that shut down the scrubber. Now it is working and the level of carbon dioxide is beginning to drop. I told Broccoli and Sunflower they should enjoy the sweetness while they can.
Don's blog also appears at airspacemag.com
