# Stunted rotala



## ap1492 (Nov 25, 2006)

I've had rotala indica growing in my tank for about a year, it seem to have gone through several relatively distinct morphologies, apparently at least in part related to repeated pruning. 

About a month ago I pulled the whole jumbled mass out and replanted just the tops with the expectation that the plant morphology and growth pattern would return to that initial observed-- rapid straight up and down growth with reddish tops and occasional ramification. Instead it's slow growing, uniformly pale green with multiple sprouts and tends to grow laterally. 

I'm sure this has been discussed before, but I'm interested to know whether others have had similar experience. 

For any trained botanists out there-- could it be caused by a change gene expression or regulation secondary to multiple prunings? 

I should probably just buy some more for the same source and compare the old rotala with the new. 

In any case the tank is otherwise happy and healthy with robust growth.


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## John N. (Dec 11, 2005)

I had the exact same experience with my rotala after a large trimming and replanting. It took a while to get back to the original growth I was used to. For me, I think it was trimming/planting trauma that effect the growth. Once everything healed, things grew back normally.

-John N.


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## DonaldmBoyer (Aug 18, 2005)

I think that it is just getting a little old to respond well to trimming....most of these plants die out (to some degree) every year or two in nature, and it may just be time to get a new group that is a little bit "younger" and robust.

Your rotala will eventually come back. Try giving them some root tabs (fertilizer).

My plant bio and physiology back in college taught me that you can's have the same plant express any different genes than what it already has in its genetic makeup. The only way you could get that is by having two different groups of rotala bloom and pollinate each other (remember Mendel's pea experiment?). It would be like if you could keep regenerating arms everytime someone cut it off, and then one day after your arm was pruned, a leg grew out instead of an arm. Sorry for the viceral example 

Hope this helps a bit.


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## JERP (Feb 4, 2003)

I periodically thin, rather than trim my plants. I pull out all of the old shoots and let the new shoots grow in. The new shoots always look emaciated at first, but they fill in quickly. I rarely replant the tops. I either trim or thin. When I to replant tops, it always takes a bit for it to become established. My guess is that it first expends it's energy growing roots.


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## DonaldmBoyer (Aug 18, 2005)

HouseofCards has rotala for sale......$3 per bunch.....very reasonable..

Just a thought....


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## eklikewhoa (Jul 24, 2006)

I noticed the same with mine.

Think the ADA stuff will work? They offer this stuff to help the plants recoupe after a trim.


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## ap1492 (Nov 25, 2006)

I dumped to the whole lot. Thanks for the input. I'll get some more later when there's a place in my tank for it.

As for plant genes, I don't know much about they other than they're similar to animal genes. The genes code for proteins, and both the expression of the gene and the function of the protein came be altered by external conditions (aka the environment).

I'm amazed at the variability in the morphology of a single aquatic plant. Presumably the process must be relatively simple given how robust the phenomenon is. Glossostigma is another example, grows straight up in low light, hugs the substrate in high light. Clearly there's an evolutionary advantage to polymorphism. It's also interesting that a plant like elatine triandra will grow just like glossostigma under specific conditions but it generally appears much different. I imagine that most stem plants can be coaxed into a variety of shapes and sizes by changing conditions. It's a fascinating process.

I suppose I can imagine a tank that contains only one species with a broad variation in height, leaf shape, ramification and color manipulated solely by amount of light and number of prunings. 

Thanks again for the input, I wish I hadn't just thrown all the rotala away, it might have been fun to mess around with it again.

And if there are any trained botanists around, a quick guide through aquatic plants genetics would be appreciated.


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## HeyPK (Jan 23, 2004)

Rotala tends to spread out horizontally when it has good light and room to spread. When more crowded, it mostly grows straight up. I have also noticed with Rotala species that when you cut them back and let them grow back from the cut stems, that the new growth is often iron deficient. Either they can't use their roots to get iron when cut back or they don't get iron from their roots and get it through the shoot, and when the shoot is cut way back, the remaining part is not good at getting iron.


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## ed seeley (Dec 1, 2006)

donaldmboyer said:


> My plant bio and physiology back in college taught me that you can's have the same plant express any different genes than what it already has in its genetic makeup. The only way you could get that is by having two different groups of rotala bloom and pollinate each other (remember Mendel's pea experiment?). It would be like if you could keep regenerating arms everytime someone cut it off, and then one day after your arm was pruned, a leg grew out instead of an arm. Sorry for the viceral example


The same organism can express different genes and they do all the time. Only a small proportion of your genes are expressed by any cell at any time.
A butterfly and a caterpillar have exactly the same genetic code, but different genes are expressed to create the two different life stages.

Similar things happens in plants. Growing points can change from producing leaves to flowers and when a meristem reaches the surface the leaves produced can change to produce emersed growth.
Genes are turned on by other genes depending on the different factors that the organism is subjected to. This means that the environmental conditions may well cause totally different sets of genes to be expressed.

Obviously all these genes must be present in the organisms genotype first.

As to ageing; this is a complicated process. In mammals telomere length (sections at the end of the chromosones) has shown to be one factor in age determination.
In plants there are a few factors at work that may reduce vigour over time. Firstly deleterious mutations can accumulate in the somatic tissue of the plant. Also plants can pick up various viruses that can reduce vigour. Plants grown from seeds will resort the genes and can instill new vigour in this case. However different plants may survive for many decades without these being serious factors. In stems plants these may accumulate relatively quickly due to the rapid rate of growth, but not quick enough to be a factore IME.

I think ap1492's problem was environmental and could have been solved. I have Rotala wallichi and it went rather brown on them lower stems. I removed the tops and replanted them and they grew away fine and normally. It took them a little while though.


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## DonaldmBoyer (Aug 18, 2005)

Yeah, but your Wallichi didn't express new genetic proteins to start growing again, did it? And it didn't come back in a shade of blue, or have new leaves either I bet.

His problem was environmental in how the rotala responded to its surrounding conditions, not that it somehow evolved and started expressing new genetic expressions. That takes thousands of years!


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## ed seeley (Dec 1, 2006)

donaldmboyer said:


> Yeah, but your Wallichi didn't express new genetic proteins to start growing again, did it? And it didn't come back in a shade of blue, or have new leaves either I bet.


Actually, expressing different proteins is exactly what it did. "New" is relative. Not new to the plant, but new as in more.



donaldmboyer said:


> His problem was environmental in how the rotala responded to its surrounding conditions, not that it somehow evolved and started expressing new genetic expressions. That takes thousands of years!


I did in fact say that I thought the problem was down to the environment too. I never said it evolved. Expressing genes is very different to new genes evolving.

Growth is caused by an organism making proteins by expressing genes in response to it's environment. We're not talking 'new' genes to the organism here, just different genes being switched on in different places for different reasons. Hence cells in stems express the genes that create xylem and plhoem cells, leaves express genes to create chlorophyll and other pigments and roots create their own cells. All of this is controlled by gene expression and different genes will be expressed in different cells. The same thing happens in your body which is why you don't have hair growing from your finger nails.

In my post I said;


> Obviously all these genes must be present in the organisms genotype first.


A different colouration (like the blue colour) wouldn't occur in a new growing point unless there was a somatic mutation, which can occur at any time and does not take thousands of years. This is how many variegated plants were found/created.

Expression of different genes is happening all the time in every organism, it's how they, and we, work.


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## DonaldmBoyer (Aug 18, 2005)

The same thing happens in your body which is why you don't have hair growing from your finger nails.


Unless you have a terratoma! 

Sorry, Ed....you were right....I didn't read closely enough! I thought that you were arguing that his rotala suddenly transformed into something new by genetic mutation, which wasn't what you had said.


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## ed seeley (Dec 1, 2006)

No worries mate.
Terratoma - not pleasant! Was looking for the little smiley that pukes all over the place, but can't find it!:heh:


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## DonaldmBoyer (Aug 18, 2005)

Yeah....that's ok! HAHA!

My wife is getting her PhD in radiation oncology, and sees nightmarish things like that on a regular basis. UGH!!!


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## ap1492 (Nov 25, 2006)

it's teratoma.


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## ap1492 (Nov 25, 2006)

So I thought I would give an update on the rotala. It's been several months and I still can get it to grow.

I still have three short, stunted stems, I've tried to grow it in two different tanks under variable conditions, it doesn't die but it doesn't grow either. It's essentially static with a few new leaves over the last several months. The current conditions are the same as when it was growing like gang busters and everything else (except the r. wallichii) is growing well. I've become more convinced that a mutation or process of longterm regulation at the transcription/translation level has occurred. I'm guessing regulation rather than mutation given the three current stems came from a different mother stem (probably). Next time I order plants I'll get a new stock of rotala to compare. I still find it fascinating.

And sorry DonaldmBoyer and ed seeley about that last snarky (terratoma) teratoma remark.


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## BryceM (Nov 6, 2005)

I find all of this discussion to be a bit confusing. Living things constantly up-regulate and down-regulate gene expression in response to their conditions on a minute-to-minute basis. This is simply part of maintaining homeostasis.

I find it not at all remarkable that you've observed changes in this rotala over time. Certainly many, many things in its environment also changed over this same time period. Lights become dim with time, other plants compete for light, nutrient levels change as a tank matures, etc, etc. There are so many factors that it would be impossible to track down even a small percentage of them. Stating that conditions are "exactly the same" is almost certainly an over-generalization. The "long-term regulation" that you're refering to is probably nothing more than the particular plant not finding conditions suitable to its growth.

If you sent trimmings from your particular plant to 10 people, you'd quickly see 10 different plant morphologies as it adapted to each particular environement. I'd be willing to bet that it would rapidly take off and flourish in several of them. I'll cover the cost to send me some if you'd like - it would be a fun experiment. I can tell you that in one of my tanks Hemianthus micranthemoides looks absolutely fabulous while Ludwigia palustris does not. In another tank the exact opposite is true. They simply are doing the best they can with what is available to them.

BTW, this discussion makes me curious about what most people do to trim various Rotalas. For the fast growers, like R. 'vietnam', I usually uproot, trim, and replant the tops. For medium or slow growers I usually trim them back heavily once or twice, then eventually find that the stem structure is just getting too thick. I then uproot the whole mess, save the best tops, and replant those.


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## ap1492 (Nov 25, 2006)

Okay, fair's fair. The conditions are not "exactly" the same, but they're close-- same lights (sure a bit dimmer), same ferts and fert schedule. Same arm dipped into the tank every few days. Same neighbors upstairs stomping around in the middle of the night, ditto for the car alarm and the air traffic overhead.

My position is this: something has happened to the plants themselves and I don't know what it is. They once grew very very quickly and now they don't grow at all. It seems to me very unlikely that it's secondary to a change in the tank, but it's possible. I readily state I don't know jack about the cellular biology of plants. 

Perhaps I should post a picture but if I do I may be accused of lying because the stems really don't look like rotala indica.

The only answer is experimentation, I'll get some more rotala-- I try to get it from the same source. 

Guiac Boy send me your address and I'll mail you a piece.


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## BryceM (Nov 6, 2005)

ap1492 said:


> Same arm dipped into the tank every few days. Same neighbors upstairs stomping around in the middle of the night, ditto for the car alarm and the air traffic overhead.


hehe.

PM sent. The exact ID of the plant isn't important. It will be interesting to see if it will take off in other conditions though. If you send some I'll post some photos to share its progress. It should be interesting to see what happens. If you have enough to send two stems I'll put it into two very different setups - one with high light, high CO2, regular ferts & soft water. The other is with lower light, CO2, almost no supplemental ferts, and relatively hard water.


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## houseofcards (Feb 16, 2005)

This is an interesting discussion and one I have experienced with my L. Aromatica. It grew unbeliveably robust for about a year that I couldn't keep up with it and then after another trim it simply never regained it's ability to grow like it did. I still have the plant but it doesn't grow as wild as it used to. I'm going to plant some of the stems in my new AS-based tank and see if it grows any differently in that tank. Donald brings out a good point. Aren't many aquatic plants in nature seasonal and simply die out after the season ends due to drought, weather, etc. If this is true maybe some of the plants we grow for extended times (many seasons) aren't really programmed to do so.


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## ap1492 (Nov 25, 2006)

--Thanks to guiac boy I've started a very rudimentary experiment with the stunted rotala. He sent me a few pieces of his healthy rotala and I planted them next to the stunted rotala. This happened approx 2 weeks ago. You can see the results below (or you could see them clearly if the pictures were better). The upshot is the new healthy rotala, Guiac's rotala, has grown beautifully even in the short period of time in a new tank whereas the stunted remain stunted. You can see how closely spaced the nodes are on the old rotala compared to the new.

--The color of the new rotala is lighter as well. You'll have to believe me when I tell you that the old rotala at one time had that same orange hue.

--I could not now convincingly argue (to myself or anyone else) that I somehow altered the old rotala many months ago-- unintentially altered at the level of gene expression or regulation-- but I think this lends the hypothesis some weight. Hopefully Guiac Boy confirms the inverse experiment.

--I apologize about the pictures, it's rather hard to make out the plants-- the first is from the side and the second from the top, both are of the same plants.

--The new plant is about 4 inches long (it was approx 2 inches when I planted it 2 weeks ago) and the old ones are 1-2 inches long (and haven't grown more than an inch in the last six months).


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## riverrat (Sep 6, 2005)

I think I would give the plants he sent you some more time. The plants he sent you might have came with a large reserve of nutrients from good conditions in his tank. Watch the plant for about 4 weeks total to see if it runs out of gas and starts to stunt from a deficiency. 


Does this make sense or am I wrong again. 

This thread is very interesting to me because like HouseofCards I once grew limnophila aromatica very well with nice coloration and then 6 months later poof.... color faded stems grew smaller. It would survive and grow just not like it once thrived in my tank.

cool thread


riverrat


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## rs79 (Dec 7, 2004)

It's just starving, that's all. Mine R. rotundifolia (you don't have indica, nobody does) is several years old.

If what you guys suggest were true it would die out in nature.


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## Kelley (Aug 27, 2006)

This is not likely true for Rotalas, but some plants do drastically and permanantly alter their gene expression as they grow more nodes. The lower nodes show juvenile morphology, while the newer nosdez convert to sexual morphology in preparation to flower. Two famous examples of this phase change can be seen in ivy plants and oak trees. The leaf shape of ivy is very different between the juvenile and the adult and juvenile oak trees do not shed their leaves in the winter. They just turn brown and stay on the tree throughout the winter. The lab down stairs from where I work studies this in corn, and it is a cool area to research. 

This got me to thinking about the plants that we grow in our aquariums and how our pruning practices influence how our plants grow. Assume one of our aqurium plants was one that underwent a phase change, and the proper growth cues were in place. If such a plant has converted to sexual growth-phase and you take just the top, replant it and discard the bottom nodes, you would lose the juvenile portion of the plant. This might not be the most aesthetically desirable growth phase for the plant. 

It's just something to think about before bed. 

Good night!


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## Scottio (Apr 29, 2006)

What I'm thinking is that you have some deficient nutrient in the tank which exists at either a small concentration or is not taken up as much by the plants as another nutrient. Possibly something the trace mix is lacking perhaps. These deficiencies don't show up in the short run since their uptake and/or the plant's ability to store them is fairly robust. However, during the course of a long period--say for a year--this lack of nutrient causes other problems with the utilization of other readily available nutrients down a particular pathway in the plant's system. Thus you may end up seeing a macro deficiency for instance. Not because there's no macros available but because these macros can't be utilized since the plant is unable to make a proper protein to use these macros.

An example would be the few essential amino acids in humans. We can't make them naturally in our bodies thus we need to get them from somewhere else. Lack of these essential amino acids don't show up right away as our body may have stores or the amount we need may be very small to not show an immediate effect. However, in the long run, pathways which utilize an essential amino acid break down and we show deficiencies not specific to that amino acid, per se, but in a more generalized way. Many deficiencies in any protein in the various pathways in our bodies may show up as multiple general symptoms since multiple proteins may affect a single pathway or a case where one pathway influences another.

Plants have a remarkable ability to store certain nutrients primarily from the fact that they are immobile and thus can't migrate if an environment is unsuitable at a given time. However, if for a long enough time these stores of an essential nutrient are not replenished, the pathway they act in will fail and perhaps a generalized symptom will show up.

In your instance with the new plant you may not see an deficiency for a long time. Perhaps you haven't seen a deficiency in your plants for a long time because this essential nutrient was introduced periodically through various means but for a long period of time has not been introduced even though you are dosing the correct ferts. There are many many variables that we are not sure of--primarily because we can't measure them--that may influence plant growth in the long run. Something in your gravel, secreted by bacteria, epiphytes, sunlight even, the list goes on and it's almost impossible to tell what exactly it could be. 

I'm sorry I couldn't provide any real answers, but more questions instead.


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## BryceM (Nov 6, 2005)

The plants arrived today. About 1/2 of the stems look like they are DOA, but the others might stand a chance. I put three stems in the 46g medium light, CO2, SMS substrate, low fert tank and three stems in the 180g high light, CO2, eco complete, reconstitued RO & daily fert tank. We'll see how they do.


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## ap1492 (Nov 25, 2006)

I like Kelly's idea. That the stunted rotala has undergone a change related to sexual maturation. There must be numerous similar examples in the animal world, I just can't think of any off hand ("can't teach an old dog new tricks" would be a stretch, but you get the idea). In addition I get the sense that perhaps Kelly knows alot more about the fundamentals of plant cellular biology (cellular botany?) than most of the rest of us. I thinks it's the best hypothesis of all, in fact I like it so much I'm going to assume it's true (at least approximately). 

As for the idea that they are simply starving-- I should have included a picture of the rest of the tank to demonstrate robust growth of several other species. The only thing I have been entirely unable to grow is rotala wallachii, (which doesn't really grow at all). I suppose the stunting could be the absence of a specific nutrient, but I think it’s unlikely given the growth of the rest of the plants, in addition I dose the standard npk and csm+b with fair regularity and feed the fish.

I should report that way back when I cut those last sprigs of rotala I was burning up the 29g tank with 130watts 12 hrs per day and the rotala was growing almost completely sideways. So there's an experiment-- get some fresh well-growing rotala rotundifolia and optimize the tank for maximal growth--- very high wattage/ferts/co2 etc. See if one can repeat my findings and produce this hypothesized seemingly paradoxical stunting. I'm not going to do it because I have limited myself to only one tank at this point. Feel free but if your publish the findings in Nature, Science or PNAS please be sure to cite my contribution.

Update on the growth-- the new rotala stems appear to be growing more rapidly even in the last few days. In a couple of months I bet I could have half a tank full. The old rotala has not disappointed and sits there sputtering and coughing, begging/pleading to be snuffed out.

If the pieces I sent Guiac Boy complete cop it (serves me right for sending them on a Friday) I’ll send him a few more.


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