You have to be careful with IAA (Indole-3-acetic acid).  Citrus trees themselves manufacture IAA,  in fact IAA is the major auxin produced by plants. IAA is what causes roots to grown downward regardless of how the seed is initially oriented.  IAA is responsible of the bending of the plant towards the light, it causes growth by cell enlargement, plays a role in fruit size and so on and on..   In the tree, IAA generally moves from the shoots down to the roots through a process known as polar transport. IAA would eventually accumulate in the roots if it weren't for key metabolic reactions by the tree that catabolizes IAA to keep it from reaching concentrations that will actually INHIBIT root growth. This is natures protection for the roots from over concentrations of IAA.  One has to be VERY careful artificially using the hormone as it would be easy to inhibit root growth instead of aidding the roots.  If you don't know what your doing trouble will follow.

Lebmung, you or any member of this form are free to contradict me, or any form member at any time. However, I stand by my post concerning the addition of Osmocote 18-6-12.   I generally make 1 cu. ft. of rooting medium at a time and the amount of 18-6-12 that I add is 99 grams.   As always, every one is free to use my advice if they wish or not.   By the way, the person that taught me this 18-6-12 information is Dr. Carl. Whitcomb, Ph.D. University of Oklahoma and Lacebark Research Inc.  Lebmung, thank you very much for being a member of this forum, your input is always appreciated..

If the cause of a yellowing in the leaf is due to a nitrogen deficiency they should regain their green chlorophyll color rather quickly.  Many times if the deficiency is due to a lack of magnesium, the return of color is slow or does not completely return.

Propagating by cuttings is ENTIRELY about energy, energy within the parent tree and energy in the cutting. Plus the associated hormonal levels in the cutting tissue.  Nearly all broadleaf evergreen shrubs and trees, CITRUS INCLUDED, root best from late August to middle of November.  This is because at that time of year the energy in the cutting is at its highest. Most of the cuttings will be rooted in 5 to 8 weeks. In general, it has been found that there is no ideal rooting medium, but several combinations of materials can provide a good, workable medium with a drainable pore space of 40 to 50 percent.  Good quality peat and coarse perlite, or peat and ground pine bark on a 1:1 or 1:2 basis by volume works well in propagation containers approximately 3-1/2 to 4 inches deep.  Be sure not to push the bud stick down so deep into the container that it is in the saturated mix, which is at the bottom of any container. The incorporation of Osmocote 18-6-12 into the rooting medium prior to the sticking of the cutting greatly increases plant quality.  With Osmocote, stimulation of rooting is substantial on some broadleaf cuttings, while others are not affected during rooting, but growth of all liners before and after transplanting is always greatly increased.

Citrus are heavy feeders, requiring more nutrition than most trees.  Not only are the tree's new leaves pure yellow, many of the older more mature leaves throughout the tree are also showing to be deficient., Grow your tree as you wish, but my suggestion is to feed the tree with conventional fertilizes.  Looking at your pictures, it is easy to determine that the tree is suffering from a drastic deficiency of nitrogen, and probably a few  other elements. You don't say how old the tree is.  A 1 year old citrus tree should be fertilized 6 times /year; a 2 year old tree 5 times /year; a 3 year old tree 4 times and a 5 year old tree and older 3 times a year.  I would suggest that you purchase a conventional fertilizer with a formula such as 8-8-8 and fertilize the tree, covering the entire area of the tree's root zone once ever two months during the growing season.   Your tree is so badly undernourished you might even give it a urea foliar spray.  Good luck to you and thls tree,

I agree 100% with Brian, Rangpur is a really awfal fruit.

Harana, the leaf symptom showing a deficiency of iron is:  NEW leaves with GREEN veins on otherwise yellow leaf.  NO wide green  border  around the vein.  NOTE: Iron deficiency often caused by high pH rather than shortage of actual mineral.

If a tree is deficient in iron, then it is proper to apply iron in order to cure the deficiency.  Just as one should not give medicine to a patient that is not sick, one should not apply fertilizer if it is not needed. Supplying iron, or anything, if it is not required is not a good idea.  Harana's trees are 2 years old.  Therefore, the recommendation for a 2 year old citrus tree is 5-LBS. of actual nitrogen per year, applied over 5 applications. The amount of fertilizer applied per each application depends on the analysis of the fertilizer. If Harana purchases a bag of 8-8-8  the solution would be: divide pounds actual nitrogen required by the tree per year (5-lb.)  by % nitrogen of the fertilizer used.   For Harana's  two year old citrus tree   SOLUTION: 5/.08 = 6.2-lbs. divided by the 5 applications, or 1.2-lbs.per each application.

All in all the citrus in the last picture just looks under fertilized, as shown by the yellow/orange veins in the leaf center with some green out on the far sides (symptom for nitrogen deficiency).  The medium that the tree is growing in looks to be OK for adequate drainage and root zone oxygen availability.  Foliage Pro is a good  citrus  fertilizer, although expensive. Citrus are heavy feeders, therefore require more nutrition than most plants.   Organic fertilizers are OK, if there are ample microorganisms present to breakdown an organic fertilizer into a  form usable by the tree.  There is no where near enough microorganisms in container culture to accomplish this. Therefore, an organic fertilizer is not recommended in container culture.  The trees in the first picture shows that they are now growing in containers that are too small for the tree's size.   When a tree's root system  has  filled out all of the available container space, its growth becomes straight up, like toothpaste squeezed our of the tube.  Theses trees also show that they now have or have had an insect problem, probably mites.  They also need more nutrition. Welcome to the forum, happy to have you as a member. The best to you and your trees.

Btian, like I always say...."Good things come to those who wait".

Years back Citrus Joe gave me a young seedling that had twin thorns.  I can't remember the name of the variety.  I no longer have it.  If I  remember correctly, it was an Australian cultivar.

Great post Citrange.

I remember J.Rozier from the original old forum,   Nasnaran being the size of a US quarter, and having 16 seeds must not have much in the way of something to eat.