The Martian

[littleminnie]

I watched the Martian last night. He survives by planting some real potatoes the crew had brought with for Thanksgiving. Then he replants some of the ones at harvest. But don't potatoes need a dormant/cold period to sprout? I forget what the needs are, but I remember trying to plant some I had accidentally hoed up and they don't grow. I guess I am too lazy to google it.

[philagardener]

Mine always seem to sprout too quickly!

[oldmobie]

Jan 17, 2016 18:43:49 GMT -5 littleminnie said:

But don't potatoes need a dormant/cold period to sprout?

Maybe it varies by variety, but in spring I planted potatoes where I hadn't before. Like always, the plants died back during the summer, so I pulled 'em out and dug up the tubers. I must have missed a few, though, because by fall I had nice sized volunteer plants. I harvested again after the first freeze. The tubers on the surface were soft on top. (Presumably freeze damage.) I reburied them. Maybe they'll volunteer again in spring?

Anyway, I don't know if they were dormant a while, but I know they regrew without a dormant SEASON and without cold. They were a red skinned variety from Walmart. Probably Red Pontiac.

[nathanp]

The answer to sprouting is, yes it is variety dependent. Most S. tuberosum in cultivated stock in temperate climates needs the dormancy period. Certainly, any that would have been sent to Mars for a Thanksgiving meal would have been some sort of russet or baking type potato, with those genetics.

Many South American potatoes, notably those with S. tuberosum from the andigena, phureja, stenotonum and a few other subgroups that are day length sensitive (not adapted for temperate growing) they would resprout like those in the book. But not the North American or European bred varieties. Some South American ones never really stop sprouting, they only slow down when they are removed from the soil. But these genetics are not really involved in most breeding efforts in Europe or North America, except in cases where the breeders were trying to bring in a trait for disease resistance, anthocyanins or caratenoids. And then they typically try to breed the day length insensitivity trait back out.

I suspect a larger problem may be that the amount of sunlight reaching Mars is probably only 60% (a guess?) or so of what it is on earth. I am sure someone could do the math, and then compare that with potatoes grown in greenhouses. I am sure you could grow potatoes with that, but it would not result in vigorous plants. Probably spindly ones with smallish tubers. Additional lights would be required to have any real significant harvest.

Now, if he had saved berries when the hab got frozen and dried out, that some TPS may have survived and could have been replanted.

So there was a bit of fiction involved with the book and movie ... well, so what, it was a fun book and fun movie!

[steev]

A bit of fiction? I thought that was a documentary! As if they'd take something as space-taking as fresh spuds all the way to Mars; like spuds would keep as long as the trip in storage. TPS; whole nother deal.

Spuds don't fit in Thanksgiving dinner, anyway; the starch is supposed to be "stuffing", easily made from dry bread (or dry cornbread, if you're lucky); Mars might be a tad short on celery or oysters, but sage isn't so hard to pack, and if you've a turkey, yee-ha!

Personally, I think, given the distance to the nearest star-system that might be amenable to life, as we know it, Mars is the best candidate for our sending a habitat that is in itself self-supporting (just so we aren't sending folks out to die if things don't work out) for practice.

[kyredneck]

I just watched it tonight and thoroughly enjoyed it. Not sure about spuds making the trip to Mars but all in all it was more realistic that a lot of other Sci-Fis, IMO.

Off topic, my favorite Sci-Fi 2015 was Ex Machina. Loved it.

[Al]

I trialled a newly developed variety on which the foliage died back really early, I assumed it had just rotted so planted something else in the same container. When I finally emptied the pot in October the original Red Chieftain potatoes had made tubers which were busily re-sprouting. Obviously no respect for seasons! But I guess they evolved at the equator in mountainous country so ancient potatoes had to contend with all sorts of mixed-up conditions. I stuck some of my precocious spouters in pots & the little leafy shoots are hanging onto life through a Scottish winter (with protection). The growth of this variety was completely different to any other potato I have grown, the chitted tubers threw out an amazingly vigorous spray of roots, then after planting in Air-Pot potato towers the underground shoots must have gone sideways because sprouts appeared through holes in the sides of the container. Probably some weird mutant Martian potato!  

[steev]

Must be adapted to zero gravity.

Not having seen the flick, I'm guessing they weren't dealing in sweet potatoes, which would have totally fit Thanksgiving (though not, for the love of god, with marshmallows, just butter and brown sugar!), had the Pilgrims been so lucky; which I think they weren't.

[littleminnie]

My husband tried reading the book but said the writing was so corny he couldn't continue. In the movie they have some cryovac potatoes that looked like a gold potato. He sets up an environment with light, air and warmth and creates water out of hydrogen and oxygen. He is a botanist. He makes soil out of Mars soil and poop. The potatoes grow ok and he eats the big ones and replants the small ones. But that part just struck me as doubtful.

[synergy]

I enjoyed the movie without analysing it too deeply as the premise is we have put a small research colony on Mars which is all a hypothetical premise from the beginning right?

[keen101 (Biolumo / Andrew B.)]

I watched this today. I found it to be a most enjoyable movie and somewhat realistic. At least the most realistic mars movie I've seen to date.

Since i don't have much experience growing potatoes i can't comment on that very much, but i will say that potatoes are probably not the best plant for mars. I've put some thought into growing things on mars and while the martian atmosphere is thin it has pretty much everything required for plant life. The main obstacles are water and collecting topsoil. I don't know about the amount of sunlight reaching mars, but i would think it would be sufficient. The only thing to consider is that with a reduced atmosphere there is more solar radiation reaching the surface. Plants that have high anthocyanins in their foliage would be better equipped to survive as these pigments are a sort of sunscreen for plants and also may serve double duty in helping plants survive in cold. Some scientists have stated that early plant life on earth may have relied on anthocyanins to collect energy from the sun before chlorophil and that instead of green plant life our planet may have started out as purple eventually replacing it with chlorophil. Some have said that is what we should look for on far away planets.

There is a martian simulated soil (regolith) one can buy for scientific experimentation. I beleive it is mostly used for robotic simulation of martian conditions. But i have thought about buying enough for a pot for fun and seeing what i can grow. I think peas or beans would be a good first plant to try since they can extract both nitrogen and carbon sources from the atmosphere. Over time this would help to establish a topsoil for other crops to be planted in. perhaps i should resurrect this desire of mine and buy some just to see what i can grow in it without adding topsoil to it.

www.orbitec.com/store/simulant.html

In the movie he used rocket fuel to collect water, used human waste for topsoil, and he grew his potatoes indoors away from the martian sun. Not sure if that was all intentional to avoid the problems i mentioned above or just coincidence. Either way it was fun to see what might work if one was forced into such an extreme survival situation.

[philagardener]

Jan 25, 2016 20:54:23 GMT -5 keen101 (Biolumo / Andrew B.) said:

Plants that have high anthocyanins in their foliage would be better equipped to survive as these pigments are a sort of sunscreen for plants and also may serve double duty in helping plants survive in cold. Some scientists have stated that early plant life on earth may have relied on anthocyanins to collect energy from the sun before chlorophil and that instead of green plant life our planet may have started out as purple eventually replacing it with chlorophil. Some have said that is what we should look for on far away planets.

Sounds particularly well suited to the Red Planet! 

[steev]

Actually, having seen "Doctor Strangelove", I think it's all about establishing that "breeding colony" on Mars, so the people responsible for destroying Earth's ecosystem can bug out and evade the fate of the 99%, whom they will cheerfully abandon.

[littleminnie]

They called the Mars days something different because they are a different length than earth. Is it shorter or longer?

[D&Y]

Mars' day is very close to Earth's: 24 hours and 37 minutes. The year is 687 Earth days, however. A loooong set of seasons.
marsmobile.jpl.nasa.gov/allaboutmars/facts/