Astrobotany: Can Plants Grow Bigger in Outer Space?

[dansmith170]

TL;DR

Can plants in outer space grow bigger because of increased solar irradiance?

According to Wikipedia Solar Irradiance at Earth's atmosphere is 1361 Watts / meter squared, compared to approximately 1000 Watts / meter squared on the Earth's surface (depending on where you are). (https://en.wikipedia.org/wiki/Solar_irradiance).

My question is, does more sunlight mean larger plants? In other words, if I put a plant in orbit, will it grow bigger than it would on Earth. From what I read, less gravity means the plant grows less support structures. My question is, more specifically, will the fruit of the plant grow larger with more sunlight in an outer space environment?

Let's assume that the plant has adequate water, CO2, soil nutrients, and that we can somehow regulate the temperature to an ideal temperature for the plant.

Thanks.

 

[BillTre]

Which plants?
Some like low light levels.
Components of outer space light (like UV) may be injurious to some are all plants.
You might try looking through the NASA website. They have a lot of obscure space associated info there.

If you are interested in just light levels, some horticulturalist has probably looked at higher levels of illumination.

 

[berkeman]

TL;DR Summary: Can plants in outer space grow bigger because of increased solar irradiance?

My question is, does more sunlight mean larger plants?

I think the first few experiments on this question did not end well for the plants...

https://www.fastcompany.com/3057288...m-near-las-vegas-provides-power-even-at-night

 

[dansmith170]

Which plants?
Some like low light levels.
Components of outer space light (like UV) may be injurious to some are all plants.
You might try looking through the NASA website. They have a lot of obscure space associated info there.

If you are interested in just light levels, some horticulturalist has probably looked at higher levels of illumination.

Thanks Bill, I'll see what I can find on NASA's website. I did try to research already, but without many results. I'll take another look. If anyone finds any papers on this topic, please post.

 

[Rive]

My question is, does more sunlight mean larger plants?

I can't say much about the gravity part, but this spring I've ruined a batch of seedlings with a slightly stronger growth light.
It was 'cold' light (LED), so they were not burnt. It was just the amount of light.

Ps.: giving it a bit more thought... Decent part of that extra intensity is pretty dangerous (short wavelength: UV and worse) radiation. Sunlight 'outside' is a big sterilizer, and once you got rid of all the nasty parts, you will be back around the 1000 W/m2 range.
Also, you'll have lot of problem with the length of daily irradiation what's used as a calendar for many plants. Same for the colour of light...

So, I would give the question a solid 'no', unless some serious genetic engineering got involved, like sunscreen-producing and such

Ps of Ps: after giving even more thoughts to this interesting problem, if it's me I would not even try to grow anything 'out there' in direct sunlight. It would be all about PV panels outside and growth lights inside

 

[256bits]

TL;DR Summary: Can plants in outer space grow bigger because of increased solar irradiance?

Let's assume that the plant has adequate water, CO2, soil nutrients, and that we can somehow regulate the temperature to an ideal temperature for the plant.

Basic assumption I guess.
But how would one know the 'ideal' water, CO2, nutrients, temperature that would be necessary for the plant with added light.

Plants are finicky.
Too much water and they could become susceptible to fungal diseases.
Too dry and they can become stunted and seed early.
Of course, exceptions apply - ie water lilies grow in water for example.

Here is an interesting thought - too much sunlight and the plant becomes too hot.
https://www.gardeningknowhow.com/ed...-bolting-what-it-means-when-a-plant-bolts.htm

 

[256bits]

Which plants?

Rightly so.