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Nutrient absorption against the direction of water flow

When plants absorb nutrition in a form other than simple ions from the soil solution, we need to reconsider nutrition transport pathways and mechanisms. A first step in connecting the dots is identifying as many dots as we are able. William Albrecht was passionate about the idea that nutrients should be available but not soluble, and he described how plants absorb nutrients into the roots even against the flow of water:

Nutrients are not washed into the plant by the transpiration stream: they enter under their own power1

In that contention that solubilities of high order are required for entrance the plant root, we are apt to believe also that such entrance is connected with the large amount of water moving from the soil into the root, passing through the plant, and evaporating to the atmosphere from the leaf surface. More water is moved through and transpired by the plant according as the evaporation rate from the leaves increases with the rise of the daily temperature, the wind, or air movement over the leaf surface, the lower humidity of the atmosphere, and the larger supply of water in the soil. But because there is a decided flow of water from the soil through the plant for evaporation to the atmosphere, that is not proof that the fertility elements are necessarily moving along that same course because of that current of water as transpiration. Calcium, magnesium, nitrogen, phosphorus, potassium, and all the other essentials are not swept into the plant because they are applied to the soil in water soluble forms of fertilizers and flooded in, as it were.

There are natural facts, some readily demonstrated in the laboratory, which refute such erroneous beliefs that the water solubility within the soil is a requisite for fertilizer availability and flow with the water into the growing crop. As the first fact, plants will grow and their nutrients will move normally from the soil into the roots without the evaporation of water from the leaves. A potted plant, enclosed in a water saturated atmosphere with carbon dioxide under a glass bell jar in the light, will grow normally. This fact tells us that while the transpiration stream is halted because the saturated atmosphere will not take any water of evaporation, the fertility elements are, nevertheless, flowing into the plant from the soil.

In research at the Missouri Station, some soybean plants were grown on soils of such low saturation of the clay by calcium, that the totals of nitrogen, phosphorus and potassium in the total crop of tops and roots were less than those of the planted seed. Such facts tell us that the fertility elements may flow out of the root, or in the reverse direction of the flow of the transpiration stream of water.

That same reverse flow of fertility can be demonstrated under the conditions used for the potted plant within the bell jar, or when there is no flow of transpiration. Such facts inform us that even in the absence of water movement within the plants, the nutrients will move either into, or out of, the plant, entirely independently of either the static or the flowing condition of transpiration water. Forces, other than the water flowing into the plant root, must move the fertility elements serving in connection with plant nutrition.

Still as another situation, the desert plants have shown according to research reports by Dr. Went, now Director of the Missouri Botanical Gardens, that nutrients go into the roots for nourishment of the plants when in the daytime the water is transpired to move from the soil to the atmosphere. Then, also, they go into the roots when at night time the atmospheric moisture of condensation moves from the plant back to the soil sufficiently for plant survival through such diurnal reversals in movement of the limited moisture supply.

These facts deny, categorically, any necessity of water solubility of nutrients for their flow into, or within, the plant for any delivery services of them by the transpiration. They tell us that the fertility, which is feeding – not watering – the crop plants, behaves according to certain laws of physico-chemical relations within the soil and plant, while the water movement behaves according to the meteorological conditions and the climatic situations controlling the conversion of water from the liquid to the gaseous form and vice versa.

Water solubility of plant nutrients in the soil is not the rule of nature for their services to plants. Rather, they are naturally insoluble there, by which condition they remain there against loss through leaching out of the soil. By virtue of that condition they are still there when the growing root comes along. But that fact does not deny their being available through other mechanisms than aqueous solution.

1. Walters, C. The Albrecht Papers, Volume 1–Foundation concepts. Acres USA, Page 219

2020-04-20T15:32:14-05:00March 16th, 2020|Tags: , , |

Endocytosis, how plant cells utilize large molecules for nutrition

When plants absorb large molecules or microbial cells through the roots (or the leaves), how are those large molecules absorbed into cells and used as a source of nutrition?

Endocytosis is one known mechanism of cellular absorption of large molecules, and has been known to be a significant method of nutrient absorption in animal cells for over 70 years. It has only been in recent decades that this process is also recognized to function in plant cells. There has been much progress in the knowledge of this process in recent years, but I wanted to give credit to an original champion of this idea and share the thoughts she expressed originally in the 1970’s, and then updated in 1993.

From Bargyla Rateaver:

Endocytosis1

The membrane is a thin layer of mostly protein and lipid (fat) molecules, in constant motion. The layer may be undulating and rough, but always it’s molecules are moving; this movement is essential to the cell’s life, as cessation of movement indicates death.

Imagine a group of large molecules, poised outside this membrane, that are ready to get into the cell. The membrane itself engulfs them and pull them down into the cell.

Such engulfment was only crudely made visible with older equipment; with the modern electron microscope advancements, even molecules can be discerned, at least in outline, so we now know that the engulfment is really a complicated, precisely programmed series of events.

This occurs because of some special activity in certain small, three-legged, protein molecules, called clathrin.These are programmed to fit themselves together into a cage, or basket, resembling a  Fuller dome, upside down.

Even if these molecules are isolated, in a solution, they assemble themselves that way, just on their own, as though their mere structure impelled them to do so. It is these clathrin molecules that give the cage its “bristly” surface appearance in sections only: actually it looks like a basket with 12 plane faces (dodecahedron)

They come from somewhere in the cell, maybe the protein factories (ribosomes), and assemble themselves at a spot on the inside of the plasma membrane, where they start to form themselves into the cage.

As they draw themselves together to make this cage, or basket, they draw the membrane down with them, like a lining to the basket. Large molecules and/or aggregates of them on the membrane at this spot, presumably waiting to enter the cell, are caught in this cage. There are several stages of this drawdown.

First, a cup-shaped depression, or pit, is formed. It comes to be lined with the membrane, that therefore must conform to the pit depression. It is called a coated pit, because of the clathrin surface.

Next, the cup becomes deeper, resembling a flask.

Lastly, the neck of the flask closes, and the pit has become a cage, a closed basket, a bag, a ball, and it contains the large, enclosed, entering molecules or particles. It is then called a coated vesicle, because it is a closed, round, ball-shaped cage, with the clathrin surface, a coating of hexagons and pentagons.

The clathrin molecules have completed their task of bringing a bag full of large molecules into the cells. They disassemble themselves, detach, and go off to do the same chore someplace else on the cell’s plasma membrane. (Sometimes the vesicles keep their coat for a while.)

Without the clathrin cage, the naked membrane ball is called a smooth vesicle. It embarks upon its predestined path through the cell, to unload its cargo of large molecules or particles at predetermined locations.

Imagine a ball of yeast dough, into which you press a finger to make an indentation; the pit made by your finger gradually smooths out. You see a kind of dimpling in and out. This is what goes on all over the cell membrane surface, all the time, at a fast pace, measured in seconds or minutes.

Although it takes time to describe this, the actual action is unimaginably rapid. Within minutes the molecular load is found in the various organelles; this means enormous numbers of reactions have taken place to engender the movements.

1. Rateaver, B. & Rateaver, G. Organic Method Primer Update: A Practical Explanation : the how and why for the Beginner and the Experienced. (The Rateavers, 1993). Page 22

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Direct absorption of molecules

The implications of plant absorption of large molecules and endocytosis are that the present mainstream model of agronomy based on measuring and managing nutrient ions is significantly incomplete, and can not be the basis for a regenerative agriculture without additional testing and management paradigms.

Bargyla Rateaver was one of the first, if not the first advocate for plant absorption of large molecules and endocytosis in North America that I am aware of. The Organic Method Primer she authored is under-appreciated for the encyclopedia of practical and agronomic knowledge it is.

Here are Bargyla’s thoughts on the subject, updated in 1993:

Direct Absorption1

Since the disastrous integration of manmade chemicals into agriculture, a huge structure of error has been built upon the false premise that “only ions can be absorbed”. Based on this, a measurement of soil and recommendation for soil have utilized the concept of “cation exchange” and the “CEC” has been the be-all of soil testing. Small structures such as ions are said to be “able to cross the membrane”. Discussions of the varied means for this fill textbook chapters on the subject of absorption.

We now know that this is all passé, an outdated formula promoted by the greedy minds of the chemical dispensers. There have been a number of investigators over the years who have documented that entire molecules were absorbed, but only small molecules. W. Flaig1 in 1968, speaking at the Vatican’s convocation on organic matter and soil fertility, entitled his work “Uptake of organic substances from soil organic matter by plants and their influence on metabolism”. In Japan, Satoshi Mori and Naoko Nishizawa proved that barley roots preferred to take up organic nitrogen compounds if offered these as well as inorganic forms.2

In the chapter on cover crops, we refer to Fritz Went, who saw in Amazon jungles that mycorrhizae absorb nutrients directly from decaying leaves on the ground. Nora M. Stark, who worked with him, in those early days before endocytosis was known, made the penetrating remark: “It is possible, that in extremely poor soils, mycorrhizae are important in supplying nutrients directly from litter to living roots”. She also mentioned that, in one case, she had “traced a hyphae from a dead fruit into a living feeder root cell”.3

Hainsworth notes, on pg 27, that carnivorous plants absorb digestion products of their prey apparently without reducing them to simple inorganic compounds.

We know now that whole molecules of any size can be taken into cells, and clusters of molecules that are particles, by endocytosis (and fluid phase endocytosis) via coated pits–extremely clever devices by an omniscient Creator: the cell membrane invaginates, trapping molecules on the clathrin-coated membrane surface, thereby forming vesicles to enclose such molecules and carry them through the cell, dropping them en route, and/or dumping unwanted or storage molecules in the vacuoles, finally returning to the cell membrane from which they came. (Plastic beads and bacteria enter via uncoated membrane regions; this takes energy. Large algal cells are taken up by fusion with the larger host protoplast, note L. C. Fowke et al.)

As there are hundreds of these coated pits and ensuing vesicles being constantly formed on cell membranes, the provision for cell absorption of compounds (and clusters of them constituting particles) is amply demonstrated; whole molecule absorption is not a small, erratic, exceptional, unusual phenomenon. On the contrary, those crowds of pits indicate that this is one of the Creator’s normal ways of circulating whatever cells need from one to another, from the environment to the cell’s interior metabolism4, or out of it to the environment, by exocytosis.

This new knowledge enables agriculture and horticulture to dispense, forever, with the theories of ion absorption. Long ago M. Dikkers told us that the plant deals with molecules, not ions.

It seems, however, that agricultural academia has either not yet caught up with the new research data, or minimizes it, or simply cannot bear to acknowledge that the monstrous pile of data accumulated throughout the world’s agricultural efforts can be wrong. One author, aware of endocytosis, nevertheless said it must be simply an adjunct to the usual ion absorption theory!

We are therefore the first to have introduced to agriculture the information and concerning the actual facts of how plants absorb through coated pits, distribute by smooth vesicles and exude via smooth vesicles, and the repercussions this implies for husbandry. It totally reverses dependence on the worthless Cation Exchange Capacity (CEC) tests, to which even organic growers still desperately cling.

We firmly believe that this discovery is the second great find of this century, second to only the disclosure/explanation of the DNA/RNA spiral, as it affects worldwide agricultural practice.

It seems that academia can afford to admit a previous error, if such does not impinge on financial benefits. In 1983 University of California researchers in San Francisco acknowledged that, although it had always been thought that a cell nucleus formed by highly complicated processes, it actually could form “spontaneously around any DNA in the cell. regardless of source, independently of genes”.

Such a nucleus had a membrane “identical to normal nuclear membrane…double layer of fat molecules pierced by many pores through which large molecules are transported”.

When confronted with his own microscopic view proving that granules can enter cells, Christopher Somerville of Michigan State University, expressed surprise. He looked at cells of an Arabidopsis thaliana hybrid, into which a plastic. PHB (polyhydroxybutyrate), made naturally by a bacterium, had been engineered. Small amounts of the plastic were made by the hybrid, in leaves, stems, roots. That the plastic occurred as particles, not ions, was undeniable, because the stained particles showed up as red dots. The dots would have had to be particles, as microscopes today are not yet able to show individual molecules (or ions!) sited in cells.

“The researchers expected to find PHB in only the cytoplasm of the plant cells, but it appears in the nucleus and vacuoles as well. That’s mysterious to us because these compartments are surrounded by membranes and it appears that the granules may be able to cross through”.5 Two strange aspects appear here: that there should be any doubt that the granules entered the cell, and that it should be surprising that they “crossed” the membranes of the cell organelles, when they must have first “crossed” the cell plasma membrane. The idea of ion entrance is implicit in the word “cross”, a concept the academic mind apparently finds almost impossible to forget; all relevant theories are based on it.

Obviously, the granules entered by endocytosis.

Much is known about this process in animal and human cells, but very little about it in plants, since there are only a handful of researchers around the world, who are working on it. Only three of them made it possible for us to show you electron micrographs depicting the stages in progress of molecules going into cells.

Plant cells differ from all others in having a cellulose wall, giving a plant rigidity; it is made of a meshwork of fibrils. It is apparently not difficult for items to pass through the cell wall, a mere tangle of microfibrils of cellulose, and there has not been any mass of data to prove or disprove this.

Inside this cellulose-mesh wall is a membrane. All living cells are surrounded by such a membrane, called in plants the cell’s plasma membrane.

No one seems to think a molecule has trouble getting through the cellulose mesh; it is confrontation with the membrane that was thought to pose all the problems. It is passage through this that has prompted so many scientists to devise explanatory theories.

In spite of all the theories, no one has ever seen the ions (such as K+), cited in soil tests, go through the membrane. Now we can track the progress of molecule masses by means of electron microscope pictures.

1 Inst, für Biochemie des Bodens der Forschungsanstalt für Landwirtschaft, Braunschweig, Germany.

2 Faculty of Agriculture, The University of Tokyo, Tokyo, Japan.

3 N. M. Stark “Mycorrhizae and Nutrient Cycling in the Tropics” in Mycorrhizae, Proceedings of the first North American Conference on Mycorrhizae, April 1969, ed. Edward Hacskaylo. Misc. Pubn 1198, USDA Forest Service, 1971.

4 Another very clever system is that of plasmodesmata, openings in contiguous cell walls, through which protoplasm (cytoplasm) is continuous from cell to cell, so that materials can move through these special, narrow passages.

5 BioOptions Vol 3 (3) pg. 2

1. Rateaver, B. & Rateaver, G. Organic Method Primer Update: A Practical Explanation : the how and why for the Beginner and the Experience. (The Rateavers, 1993). Page 21

The contributions of soil biology to plant nutrition

Have been known for decades, but have not gained traction in a business environment that offers no economic incentives to agribusiness for reducing or eliminating the need for applied fertilizers. Applied fertilizers produce an apparent magical response, and we are discovering that is indeed magical since it can not be sustained into the future.

Soil Microorganisms and Higher Plants is a classic, and worth reading if you desire to understand more of what soil biology can deliver, here are a few excerpts:

The biogeny of soil is the most significant indicator of its fertility. As soon as the activity of a microbial population begins in a rock, the first signs of fertility are manifested. The degree of soil fertility is determined by the intensity of the life processes of the microbial population.

It is impossible to solve problems of pedology, not to speak of agriculture and plant growing, without taking into account the microflora of soil. Plants are a very strong ecological factor, selecting certain species of bacteria, fungi, actinomycetes and other inhabitants of soil. As a result of wrong agricultural practices and crop rotation, the soil becomes infested with harmful microbial forms. By use of suitable plants in the crop rotation, one may change the microflora of soil in the desired direction and eliminate harmful organisms, in other words – restore the health of soil. Page 2 – 3

Increased accumulation of microbes in the root soil was first observed by Hiltner in 1904. He proposed the term  “rhizosphere”. In investigating the root system of various plants, Hiltner came to the conclusion that the accumulation of microbes in this area was not accidental and it was caused by the biological activity of the roots. Page 281

The microflora of the root zone is of great importance in plant nutrition. Growing near or on the roots, microorganisms, together with the plants, create a special zone – the rhizosphere. Soil in this zone differs in its physical, chemical, and biological properties from that outside the rhizosphere. The interactions between microbial species and between microbes and plants result in the formation of plant nutrient compounds. Substances present in the soil are subjected to a greater or lesser extent of processing before their absorption by the roots. The plants do not absorb those compounds which are characteristic of soil outside the rhizosphere but rather they absorb metabolic products of the rhizosphere. The rhizosphere microflora prepares organic and inorganic nutrients for the plants. Page 264

In the rhizosphere, iron, manganese, and other metals occur in combination with organic compounds formed by microbes. Amino acids, organic acids, and other metabolites of microbes form stable complex compounds. They are utilized by plants and used as a source of specific organometallic nutrients. These are found in greatest concentration in the rhizosphere and are preserved in the soil for long times. Page 281

Free PDFs of the book can be found on our reading list here.

2020-03-16T14:14:50-05:00February 27th, 2020|Tags: , , , , |

An introduction to rhizophagy

Did you know that growing root tips can absorb entire microbial cells? Or that symbiotic endophytes change the behavior of soil-borne pathogens to become beneficial organisms, and provide nutrients to the plant?

I was delighted to discover Dr. James White’s publications on rhizophagy1 and the role of endophytes2 in plant health, and even more thrilled during our interview on the podcast with the updated information that was shared.

I have long been passionate about understand plant absorption of non-ionic nutrients. Of all the research published related to this topic in the last few years, I have been most excited by the reported capacity of growing root tips to absorb entire microbial cells and extract needed nutrients from those cells, then release some of the microbes back into the soil to repeat the process all over again.

The future of agronomy and plant nutrition will be based on understanding the science needed to supply one hundred percent of a high yielding crops nutritional requirements as microbial requirements, and not as simple ions from applied products.

I have had so many exceptional interviews on the podcast that I can’t say one is the best ever, but this one will definitely be among my personal favorites for a long time. It is a must-listen, and the papers are ‘need to read’. I highly recommend.

1. White, J. F., Kingsley, K. L., Verma, S. K. & Kowalski, K. P. Rhizophagy Cycle: An Oxidative Process in Plants for Nutrient Extraction from Symbiotic Microbes. Microorganisms 6, (2018).
2.White, J. F. et al. Review: Endophytic microbes and their potential applications in crop management. Pest Manag. Sci. 75, 2558–2565 (2019).

2020-03-16T13:57:12-05:00January 21st, 2020|Tags: , , , |

Building Available Phosphorus without soluble fertilizers

Nutrients should be available, but not soluble ~ William Albrecht

To develop regenerative farming systems, it is important that any soil amendments or fertilizers we add have a positive effect on both plant health and soil biology. It is not acceptable to have a positive effect for one, and a negative for the other.

Many soluble fertilizers are known to have pronounced negative effects on soil biology, particularly nitrogen and phosphorus.

One of the objectives of regenerative agronomy is to develop biological nutrient release to the point where limited or no additional fertilizers are needed to support the crop. A question is, how do you get to this point when your soils are very low in available nutrients to begin with?

In the case of phosphorus, a practice we have recommended for over a decade is to combine rock phosphate with manure before application. We generally observe approximately four times greater phosphorus response in soil and plant sap analysis as compared with an application of straight rock phosphate.

Soluble phosphorus applications are known to suppress mycorrhizal fungi colonization, phosphorus solubilizing bacteria, and phosphatase enzyme activity,  creating a continued dependence on soluble phosphorus applications. Biology has been replaced with spoon feeding chemistry.

New research just out reports that combinations of rock phosphate and manure increase phosphatase enzyme activity and organic matter1.

Increased plant availability, but not water solubility.

Which also means not leachable, and produces no water pollution. Perfect.

1. J. A. Omenda1* K. F. Ngetich1 M. N. Kiboi1 M. W. Mucheru-Muna2 D. N. Mugendi. Soil Organic Carbon and Acid Phosphatase Enzyme Activity Response to Phosphate Rock and Organic Inputs in Acidic Soils of Central Highlands of Kenya in Maize. International Journal of Plant & Soil Science 30, 1–13 (2019).

2020-03-16T13:35:09-05:00December 11th, 2019|Tags: , |

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