Why some plants are developing Aerial roots in aquarium ? Is this the sign of lack of soil nutrition ?

[jubin sharma]

Plants like rotala and ludwigia are develpoing side aerial roots ? is this depicts less soil nutrition ?

 

[_Maq_]

Some very precious compounds (like some plant hormones) are synthesized solely in roots. That is the general reason for which all higher plants create roots even if they don't reach the substrate.
That said, the state of nutrition can significantly influence creation of roots. General rule is that plants invest more energy in root creation when nutrients are in short supply.

 

[Tim Harrison]

Welcome to UKAPS.
Aerial roots can form for a variety of reasons, not just in the search for nutrients. It's pretty easy to tell if it is a nutrient deficiency response since the rest of the plant will probably show it too.

 

[Hanuman]

Plants like rotala and ludwigia are develpoing side aerial roots ? is this depicts less soil nutrition ?

Some very precious compounds (like some plant hormones) are synthesized solely in roots. That is the general reason for which all higher plants create roots even if they don't reach the substrate.
That said, the state of nutrition can significantly influence creation of roots. General rule is that plants invest more energy in root creation when nutrients are in short supply.

Which rotala and which ludwigia are we talking about here?
In my experience some species will more readily throw aerial roots than others. For example I've never seen any aerial roots on L. meta or pantanal but Cabomba furcata is a root fointain.

 

[zozo]

is this depicts less soil nutrition ?

No, it's not, but on the contrary... most stem plants do this, especially in nutrient-rich water... Why is the big question, my best guess is because the plants are actually bog plants that naturally want to grow emerged and flower and seed to procreate. And it considers fertilized water not as an atmosphere but as a growing medium to root in. A submerged 'Aerial Root' is an (obvious) misnomer in our hobby it isn't an aerial root it is a water root.

If you would keep it growing like this and never trim it, it will grow in a massive plant/root clump filling the entire tank up to the surface and then it will have enough mass and hold to grow its final goal emerging into the atmosphere.

Bog plants have a remarkable sensory mechanism controlling this switch between the 2 forms. Sturdier growing plants do this a tad easier for example the Pogostemon stellata, this plant only needs to reach the surface with its crown leaves, it will pick up that it is at the surface and switch the growing form to emerged and then grows on like this above the water. Then it will shed all submerged leaves and solely produce submerged roots. It can still produce runners that first start with submerged babies but these are actually single plants by themselves striving for the same goal, the surface and emerged growth to flower and seed.

Submerged grow form from actual bog plants is an evolutionary intermediate survival technique... We only force them into this form and keep it this way by trimming it down. And then the plant can only combat this again with rejuvenation in it's submerged form.

 

[sparkyweasel]

If they are aerial roots your water level is too low.
Roots that are not under the substrate are adventitious roots.