Continuing fruit production long past normal ripening.

[aman]

We knew back in the 70"s that on a cellular level the rind of a fruit produces the carbohydrate storing cells as it expands outward making the fruit larger. Then a chemical hormone at some point tells it to stop and orders it to ripen.

Can't we interupt the cycle and block the stopping hormone and with hydroponics assist supporting the extra growth?

The fruits, vegetables, and grains could be supported to grow rice grains as big as a room. Just for thought.

Just aman

[fafalone]

The hormone primarily responsible for ripening is ethylene, and the primary growth hormones are auxins. We are able to somewhat manipulate these hormones, but our methods still can't give us total control. Part of the ripening problem results from photoperiodism. Photoperiodism is a gibberellin-mediated response to daylight the uses very precise responses to phytochrome concentrations (they are broken down by sunlight), so it is neccessary to precisely control the length of day to maximize ripening results.

 

Plants have a limit on their growth. The super-sized plants you see are the result of a condition called polyploidy, where the plant (usually an angiosperm) has extra sets of chromosomes. We also have some ability to control this as well, however it can produce undesirable effects, and there's always the anti-genetic engineering nuts protesting it.

 

I hope this helps.

(and unlike some people on this forum, I'll provide documentation that backs up what I said if someone doesn't believe me)

[Guest Unregistered]

Thanks for the insight. I see that we control the light in hydroponic gardens but the stop producing and ripen instruction still gets engaged. Controlling periods of light is no solution and maybe like you implied the reproducing cells may only have a certain life span.

It sounds like genetic manipulation is the answer. Maybe find out which gene is doubly expressed in the mutants and double it in an ordinary fruit. I'm for the research. The food would be safe. Only Knuckleheads would want to stop something that could conserve so much land and halt slash and burn or logging of old growth forests.

By the way NASA is looking for ideas on how to provide maximum oxygen and food production from hydroponics for the Mars trips. The best of what we have today just doesn't cut it.

Thanks

Just aman

[aman]

it seems we have chemicals now than can contribute to unrestrained growth due to our cancer research and other human biological research. Human cells are so much more difficult than plant cells to work with so we should be able to control continuous reproduction of fruit meat. A fruit should be able to grow as large as we want. I think a little research money is warrented.

Just aman

[fafalone]

We can already do that. Unlike humans, plants can survive with a condition called polyploidy, extra sets of chromosomes. This causes excessive growth. The more sets of chromosomes, the larger it will be.

[RAB]

Seems to me there is a practical limit to fruit size in that the larger it gets the more uneven the ripening process. Imagine an orange the size of a basket ball; the portion that ripens first would possibly spoil before the rest caught up.

[fafalone]

Perhaps if you inhibited ethylene while increasing auxins; this would create growth without ripening. Once ethylene is reintroduced to the plant, it should ripen pretty evenly.

[blike]

You nerd. I can't believe you knew that off the top of your head.

[fafalone]

Read up, I basically repeated my original reply Which at the time I knew off the top of my head because it was around AP Bio test time. But actually I do remember it =/

[Skye]

People can survive with extra chromosomes. Men with an extra Y chromosome (XYY) are reproductively/mentally normal, though taller than average. I don't know if you could keep adding Y chomosomes to make all star basketball players though:-p

[Skye]

Better add this...

 

We can't survive with extra sets of chomosomes though like plants, I just thought it was interesting that we can make bigger people by adding chromosomes.

 

Could auxins be added to the soil and taken up by the plant to increase the size of fruits?

[fafalone]

Possibly, but inducing polyploidy is alot more effective.

[RAB]

polyploidy seems like the right approach because the whole plant needs to be larger to produce larger fruit: bigger stems and branches to support higher fruit weight, leaves to make materials faster, etc.

 

Is fruit the small size they are because anything bigger couldnt mature (produce seed) within the growing period?

[fafalone]

It just doesn't grow larger than that in normal conditions; the life cycle doesn't allow it. Extreme polyploidy (some of the record holding plants have had 8+ full sets) simply doesn't occur naturally.

[RAB]

Is it that multiple sets of DNA can replicate proteins faster in a cell than a single set can? Are polyploidal cells physicaly bigger than normal cells?

[Giles]

In certain specific cases (fruit fly salivary glands) this occurs; usually polyploidy causes trouble unless the extra chromosomes are disabled. Transcription and tranlation can be speeded up without using extra DNA (check out transcription in the nucleolus during cell growth).

[Skye]

I read in a bio book the other day that auxins are routinely sprayed onto fruit trees to increase fruit growth.

[aman]

Since we can keep plant cells healthy in the lab, I had an idea about painting a screen with inner rind cells of fruit and let them produce fruit by feeding nutrients on one side of the screen while harvesting from the other. The cells should produce as long as they are not shut off by the ripening triggers.

The size of the fruit should not be restricted and before the fruit is harvested the triggers could be allowed.

The nutrients could be provided by panels of leaf cells in solution so a lot of waste plant support structure could be eliminated.

It should be easy to make a grape as big as a garage.

Just aman