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How a Leaf of Pine Tree Grows Roots, as Explained by Stem Cell-Organism Theory
Mindoro pine trees in Mindoro Occidental, Philippines
Needle fascicles that grew roots (Photos courtesy of Ms. Rene S. Fontanilla, Ph.D.)
Stem cell-organism theory as basis of cloning of plants
Let’s use a theory to explain or interpret. Take the stem cell-organism theory “A trigger induces stem cell to differentiate into an organism.”
I formulated this theory in a Hub “Stem Cell Therapy Based On The Stem Cell-organism Theory.”
This theory holds true for multi-celled organism like plants, trees, and human beings. We will use materials and results from a doctoral dissertation.
“A highly significant interaction between the size of the needle fascicle and hormone treatments occurred based on percentage rooting (Appendix Table 10).
“Long needle fascicles applied with 200 ppm IBA (T5) yielded the highest percentage rooting at 17.71% (Figure 15), followed by the short needle fascicle treated with 300 ppm IBA (T6) at 13.54% (Figure 16). The untreated (T1) long needle fascicles and Superthrive–treated (T2) short needle fascicles showed the lowest percent rooting of 1.04% (Appendix Table 13). Low percentage rooting was obtained with remaining treatments, namely: 1) both long and short needle fascicles treated with a combination of Superthrive and 200 ppm IBA (T3) at 9.37% and 8.34%,respectively; 2) long needle fascicles exposed to 300 ppm IBA (T6) at 7.29%, 3) short needle fascicle treated with 200 ppm IBA (T5) at 6.25%, and 4) long needle fascicles subjected to Superthrive mixed with 300 ppm IBA (T4) at 4.17% (Table 3 and Figure 17).“Short needle fascicles treated with a combination of Superthrive and 300 ppm IBA (T4) and the untreated (T1) short needle fascicles did not produce roots (Figure 16). (Fontanilla, R. S., Ph.D. Macropagation of Mindoro pine (Pinus merkusii Jungh and de Vries) Using Shoot Tip Cuttings and Needle Fascicles. University of the Philippines Los Baños, 2008).
Let's isolate the statement for discussion:
“The untreated long needle fascicles and Superthrive–treated short needle fascicles showed the lowest percent rooting of 1.04%.”
Superthrive is a hormone, a supplied trigger. The needle fascicles of Mindoro pine not supplied with trigger (hormone) were grown in sterile garden soil. Ppm means parts per million. IBA means indole butyric acid, a plant hormone.
Let’s take note of some features of the experiment:
Long needle fascicles were used.
Short needle fascicles were used.
Untreated means no hormone was supplied.
The assumptions were:
The long needle fascicles had more carbohydrates than the short needle fascicles.
Both the long and short needle fascicles are adult cells that contain stem cells.
The long needle fascicles contain more stem cells than the short needle fascicles.
From the statement above, long needle fascicles not supplied with hormone produced roots. This is in contrast to the expectation that needle fascicles not supplied with hormone do not produce roots.In the third paragraph of the quote above, Superthrive and IBA 300% cancelled the effect of each other in inducing rooting, or they were antagonistic. This was observed in other parts of the experiment.
A pertinent question is: how did the needle fascicles not supplied with hormone but grown in sterile garden soil produce roots?
The sterile soil still contained water, and nutrients. It is usual observation that leaves of plants do not grow roots. The cactus is an exception. A cactus leaf grows into another whole plant when planted in ordinary garden soil or left lying on the ground.
The answer to the above question is: Nutrients in the soil triggered the stem cells in the needle fascicles to differentiate and grow roots. There is a minimum amount of stem cell in the needle fascicle required for growing roots. Food had been stored in the cotyledon. Root is the priority requirement for survival that is why it is the first to be produced. It is like a mongo or soya seed. When you germinate the soya seed, a root (also called hypocotyl) is the first to grow followed by leaves. Sometimes root and leaf emerge simultaneously. The purpose is that the root will get food from the soil or any source to sustain life when the food from the cotyledon runs out. The leaf will manufacture food.
A multi-celled organism exhibits integrity. It will regrow missing or damaged cell, or tissue, or organ. It does the same for the liver, kidney, skin, bone, blood. Humans have gatekeeper genes like the gene p53 that controls cell growth. Humans have caretaker genes that ensure the integrity or the set of chromosomes or genes. Chromosomes are the blueprint of the integrity of multi-celled organism. However, there are barriers to the expression of chromosomes or they are damaged such that their expressions do not manifest.
Triggers induce stem cells to clone themselves and at the right amount, stem cells repair damage. In our specimen, a pine tree, stem cells in the leaf reconstruct the leaf into a whole pine tree.
Actually the doctoral dissertation from which we obtained our sample for explanation involves cloning. In some other pine species used for cloning, the needles produced roots. When planted in a pot or field, they developed stems, leaves, branches, then flowers and fruits including seeds.The hormones so supplied served as trigger to induce the stem cells contained in the needles fascicles to differentiate into whole pine tree.
Cloning is applied on Mindoro pines because trees are dwindling owing to over exploitation. Another reason is that a tree bears flowers and fruits once in two years. On top of these, the seeds have low viability.
A needle fascicle with sufficient amount of stem cells will grow into a pine tree when planted in garden soil with sufficient food.
In humans the stem cell-organism theory also explains how stem cells and adult cells (eye, blood, ear, blood, heart, liver, kidney) reprogrammed back to stem cells can be used to trigger repair of damaged adult cells. That is called stem cell therapy. I have a Hub on this topic.