Iron (Fe2+) and other deficiencies

[BenHehle Beamz]

Hi all,

Iron deficiency is a big topic in AP. Well, i just found a good example of a typical Iron deficiency and i thought i will share it.

As most of you know: Plants need Macronutrients and Micronutrients (Essential nutrients), to complete its life cycle. Every element has its own function, and it cannot be replaced by another element.

Macronutrients are called Macronutrients because the plant needs it in big amount (>500mg/kg dry weight) and Micronutrients in smaller amount (<100mg/kg dry weight).

Some deficiencies show the same symptoms, in many cases chlorosis (yellow leaves), so sometimes its difficult to say which element causes the deficiency.

#There are only N,P,K, (Mg) which are Mobile nutrients - the symptoms occur on older leaves first.

#Immobile nutrients (such as Iron), if there is a lack of one of these, the symptoms are shown on younger leaves first.

Lack of Nitrogen or iron, both show yellow leaves. So, if you look at the picture, you can see, the older leaves are dark green, so it cant be Nitrogen, as it is mobile and occur in the older leaves first.

As the young leaves are completely yellow, you know it is iron deficiency.

So, by looking at younger and older leaves you know if its a mobile or immobile element which causes the deficiency.

If anyone is interested in more pictures of deficiencies, i can post them time by time. (sorry for disturbing the people who already knew it)

[TCLynx]

That is very good info about looking at older and younger leaves to tell which deficiency it is.  However, I'm going to add to it a little bit.

Notice that the veins of those younger leaves are still green while the tissue between is yellow, that is how iron deficiency show first in the young leaves, the veins stay green longer while the tissue between is what yellows first.

Now it's normal for new growth to come in a little bit lighter green but it should be greening up as the leaves open.

Very good example Ben

[BenHehle Beamz]

Nitrogen deficiency in legumes

Chlorosis (yellow leaves) of older leaves, slow and stunted growth. The whole plant just doesnt look healthy, yellowish and "lame".

[RW]

Very good example. Do you  mind if i use the picture in an aquaponics class i teach at a local community college (with full credit of course)?

[BenHehle Beamz]

Of course you can :)

RW said:

Very good example. Do you  mind if i use the picture in an aquaponics class i teach at a local community college (with full credit of course)?

[Luis Arteaga]

I will like to thank you all for the nice work giving us examples of this deficiencies, however, the ilustration will be more complety if you show us what to do to correct such a case, and how to prevent the plant arriving to this stage, this should be the best of both worlds, congrats to you all.

[Joe Bifano]

I have a question on another deficiency I may have. I have been doing my fish less cycling and found that my plants are really growing very slow. Lettuce is doing the best but still slow.

I did several tomato plants and they all have stopped growing pretty much but look strong. Here is something that is not correct. They are all dark green on the top and velvet purple underneath. Do I have a phosphorus deficiency?

What can I do to correct it?

[TCLynx]

Joe, I'm not sure.  However, can you share some more details about how the plants are growing?  Are they in a system or just seedlings in soil?  If in a system, is it a brand new system?  Fishless cycling?  See fish feed or pee provide plenty of phosphorus but pure ammonia cycling only provides nitrates to the plants and seaweed extract doesn't provide phosphorus either.

[Joe Bifano]

The plants are seedlings in peetmoss and vermiculite in 2" net pots. I am in fishless cycling right now and using this water for the plants. I have added Maxcrop seaweed about 4 handful's and about a quart of Maxcrop seaweed with Iron. So pee will help this? What is a good post on this if that is what I need?

[TCLynx]

There is a group about fishless systems and I've started threads on Pee Ponics over on BYAP.  If you are fishless cycling with urea or pure ammonia then you might be a bit short on phosphorus.  If you don't mind the idea of pee ponics you might just switch over to hummonia instead of pure ammonia for your cycling or perhaps some one else will have an alternative phosphorus source for you until you get some fish going.

[Joe Bifano]

I will go over to BYAP and take a look at what you have there. I am seeing yellowing and other things as well like the nitrogen is not there as well as no phosphorus.

[Vlad Jovanovic]

Joe, you can also use some rock of phosphate for 'immediate' use (granite dust has tons of phosphate too). The 'organic' route would be crushed up powdered bones (or bone meal) but that seems to be rather slow acting and your bacteria will still have to break it down first so that those plants can use it.

I don't know what your air/water temps are, but P uptake is 'very' temp related. (This last year I took a young pepper plant and isolated it in a coldish 'chamber', and observed... even though I was plying it with P fertilizer, the plant stunted and new leaves turned purple. P seems to be very mobile in plants.... Then when I placed the plant in a nice warm environment with the others, the purpling went away and the plant continued to grow). 

The purple color is caused by the accumulation of sugars (since P is used in various energy transfers and the production of ATP in plants, when deficient, I guess the sugars just sit there instead of being used up for energy) which then causes the production of anthocyanin (the purple pigment). Stunted growth and poor root development too.

TC's pee-ponics would be a great way to introduce some P, but you need to age the hummonia for a couple of weeks.

You could foliar feed some mineral phosphates (maybe the quickest way, and it shouldn't take much...either way it should clear up quickly once you introduce some P. Just don't wait too long, whatever you do...

I've noticed that if you keep a plant stunted for too long, funky stuff sometimes happens...Like when you correct what ever it was that was keeping it stunted, it may go immediately into flowering even though it's only a couple of inches tall. (Don't worry too much about that part though, as those were the results of some rather 'extreme ' (how long can I keep a plant in limbo then bring it back type) experimenting...Just taking care of it as soon as you can, would obviously be best for your tom's...

[Joe Bifano]

@Vlad Because of where I live (out in the boonies) I need to get something on line.  Can you recommend something from Amazon or a foiler spray product that would work.