Interesting question Marv.

From pictures I've seen of upside down,so called TopsyTurvy growing it doesn't seem to have made a difference.

But transpiration in my opinion is more strongly related to air temps and humidity and wind, rather than gravity.

The rate of transpiration is also a variable in fruits being subject to BER since up take from the roots of Ca++ is not usually the problem in most situations,but circulation within the plants of water and nutrients/minerals,such as Ca++ is, so with greater transpiration, out goes the Ca++ that's dissolved in water.

And that leads to little to no Ca++ getting to the blossom end of fruits, which leads to BER. There's also internal BER which occurs and nothing is seen on the exterior.

Carolyn

I guess noone has any experience with this or knows of no information relative to it?

Here is an article of interest that goes along with the idea that gravity decreases transpiration rates.

http://jplaz.com/wordpress/2012/07/transpiration/

Marv, below is your link in clickable form.

Tagestes patula is a marigold and has a very different plant habit than do tomatoes.

Tomatoes can cascade downwards, for almost all indet and semidet varieties and I don't think one can compare the leaf structure of marigolds with tomatoes either.

If one looks at topsy turvy growing tomatoes the leaves are not upside down, they face upwards.

Some marigolds can cascade down, but Tagetes patula is a dwarf that naturally forms mounds. I've grown it.

I think it would be difficult to compare a dwarf marigold growing upside down with the same for a tomato.

https://www.google.com/#q=tagetes+patula

Look at the leaves? Totally different as I see it.

Just me own opinion, as usual.

Carolyn

Here is a link that might be useful: Marigold transpiration

There have not been all that many studies done on gravity and transpiration as it turns out. So, something is probably better than nothing. And since it agrees with what I was thinking..........................

This statement is not logical (to me) Mr Spock: "Because the rate of transpiration was greater when the whole plant was upside-down and conversely slower when parts of the plants were oriented correctly, it is not unreasonable to suggest that gravity does increase the rate of transpiration but only before the plant exhibits gravitropism."

Reason for this assumes that plant wants to grow in upright posture for some reason and resulting bent stems do not "transpire" as efficiently as straight one. Could this (gravitropism) be a result of its proclivity out seek out better sources of light (or new civilizations) and not necessarily to keep leaves from drowning? I do not know. I know that this occurs rather quickly when light orientation is changed on seedlings. And it has nothing to do with the moisture content of their roots' soils. Also note that the all of the non-root growth of the "upside down" plants was probably still below its soil surface in a gravitational sense. Which implies that gravity should have continued to have an effect on transpiration if it, in fact, does. Also, the compromise of transpiration due to the of twisted stems deformation notion is, to me, rather flimsy.

Jeff

This post was edited by reginald_25 on Wed, Jan 22, 14 at 10:25

Plants have systems that defy gravity. There are a lot of trees over 100 ft. tall and do just fine.