Seed to Seed, Critical Points of Influence
Dan: Alright, so I’m given the opportunity to introduce a number of really quite amazing people today and tomorrow and John is certainly one of them. Somebody who I’ve known for ten years, John, plus or minus? Since we’ve met, we have gone separate paths. John is traveling the for-profit consultant, agronomist path and I’ve been working on the non-profit educational organization path but I feel like it’s been very, very parallel. So I’ve learned immense amounts from him over the years, certainly a lot of what people who have heard me speak about, I’ve actually gleaned from John. So I’d like to offer a lot of, thank you. Thank you John.
So we talked about all the critical points of influence in the plant’s life cycle, where we lose the most yield, the most capacity, and the most potential. Seed is one of those topics that I think is never appreciated as much as it needs to be in relation to this. So I’m really happy to have John talking from the aspect of how we can improve seed quality.
John: Thank you Dan. Good afternoon everyone. I am honored to be here today. Thank you Dan for inviting me and thank you for that introduction. Many interesting things have happened in the journey since Dan and I first met a decade ago and the pathway that I have gone down as Dan described it, is after founding Advancing Eco Agriculture what we really became known for was helping farmers grow crops that were very resistant to disease and insect pests by balancing nutrition to really enhance their immune system.
What started us down this pathway and made me personally very passionate about disease and pest resistance is based on some experiences that my family had on the farm where I grew up. We had a three year period of time in which we lost a substantial amount of the crops that we were growing to diseases such as downy and powdery mildew, and pesticides were completely ineffective.
From those experiences we started working with plant nutrition to try to increase a plant’s immune system to increase resistance. I discovered that it is possible to grow and produce crops that are completely resistant to diseases and insects which is a really big claim to make since I’m not talking about partial resistance, I’m talking about complete resistance. As we started working with more farms and as soil health and plant health began to evolve, two other things happened as well which were incredibly powerful and gave me tremendous inspiration.
The first was that when we began developing plants that had such an exceptional level of immunity, not only were they capable of being resistant to diseases and insects but they had the capacity to transfer that immunity to the people who consume that food. When you have plants that produce extremely high concentrations of secondary plant metabolites those secondary plant metabolites are actually also very strong immune enhancers for our own immune system as well.
The second piece was when we began working with farms in extremely degraded environments with very degraded soil conditions, we realized that we have missed one of our bigger opportunities to build soil health. Particularly within the domain of organic and biological agriculture the common paradigm is that it takes healthy soil to grow healthy plants. We discovered that there is another side to that coin, and that the fastest way to regenerate and rebuild soil health is to grow extraordinarily healthy plants. When you grow really health plants and really health crops they rebuild soil faster than anything else that you can do. And I can tell you right now that on commercial farming systems on a commercial scale, anything over a couple of acres, you cannot economically justify to put on enough compost or enough soil amendments to match what a really healthy crop can do.
So it is actually possible to grow crops that provide food for people and to regenerate soil at the same time when plants cross a certain threshold of health. And that to me was incredibly empowering and inspiring because that now gave us the means with which to not just grow a tremendous amount of food but also to regenerate soil health at the same time and to sequester extraordinary amounts of carbon. This is not the purpose of the discussion today but I think it is worth commenting on, that on some of the farms that we have worked with we have seen soil organic matter increases by 1% per year on dry land farming while growing a corn crop every year. That is extraordinary and all of the crops that we grow today have the potential to accomplish those kinds of results.
Today, we’re working on several thousand fruit and vegetable production farms, mostly here in North America but increasingly international as well, South America, Africa and Europe, and we have really become known in the commercial fruit and vegetable production space for three things. One is for increasing disease and insect resistance which is the original intent that we began with. Second is for producing extraordinary fruit quality and firmness, shelf life, flavor…any parameter that you can think of that impacts fruit quality. We have been very fortunate to learn a lot about how to manage fruit quality with nutrition. And then the third piece, which I personally believe is very important, is we have become known for helping farmers make more money and be more profitable using regenerative farming systems than conventional farming systems.
I personally am really passionate about the work that we are doing. My personal vision and goal is that I want these regenerative models of agriculture to become the status quo around the world against which everything else is measured. In order for us to achieve that goal we have to be able to demonstrate to farmers that they can make more money using regenerative farming systems than conventional farming systems. We have begun seeing this now in our work where large scale commercial fruit and vegetable growers are wanting to shift and discontinue pesticide use, and that is something that I am really inspired by.
Along this pathway I made a very interesting observation, and it’s something that Dan and I have talked about many times over the last decade, is the substantial impact that genetics have on nutrition and on nutritional integrity and also how nutrition in the field impacts seed production and fruit quality production.
So Dan invited me here today to talk about seed quality. And through this discussion this afternoon, I’ll be talking about many different aspects of plant physiology and plant development in a very broad high level context and you might think that it doesn’t directly connect to seeds but it will come around full circle to where we will see how everything that happens in a plant’s life impacts seed quality. When we look at fruit and vegetable production, which is the context that I will largely be speaking from because it’s one that I’m most familiar with, the reproductive parts of the plant are the weakest parts of the plant. They are physiologically the weakest. You think about a cucurbit crop such as cantaloupe or zucchini or winter squash or cucumber or something like that, where do the cucumber beetles go first? The blossoms and the flowers. If you think about apples and apple production, where are the first and the most severe insect attacks? On the flowers. This isn’t universally true for all crops but it is true for the majority of crops that the reproductive parts of a plant from a health perspective are often the weakest part of the plant.
And the reason for that is because those reproductive parts of the plant require higher mineral concentrations and higher nutrient concentrations than any other part of the plant. The concentrations of zinc and manganese and copper and boron and all these trace minerals in the reproductive parts of the plant are often ten to twenty times higher than the surrounding tissue. Sometimes as much as sixty to eighty times higher, and they need to be because the embryo formation, pollen formation, and all of the different parts of the reproductive system require extremely high trace mineral concentrations. So what I want to talk about today is first of all how this happens, why it happens from a plant physiology perspective, and how we can prevent it from happening.
So when we talk about genetics I really like to begin with this quote from Luther Burbank where he says that heredity is nothing more than stored environment. Today within genetics there is (completely excluding the conversation about GMO’s which is a conversation and dialog all and in and of itself) there is constant effort to breed crops for high flavor, better shelf life, greater yields, specific disease resistance, for any of these various characteristics that we’re looking for. And those breeding efforts certainly have some value but they are incomplete when we focus purely on the genetics piece. That means we are completely missing the environmental piece and we can see this very clearly. When Francis Enkrik first identified and postulated the structure of DNA, we believed that with our understanding of DNA and genetics, we would be able to produce genetic treatments and reverse and halt all degenerative illnesses, stroke, diabetes, heart disease etc. We believed that genetics held a solution for all of those problems but as we learned more about genetics and realized that we didn’t really know what we thought we knew, from that emerged the science of epigenetics.
The basic premise of epigenetics is simply that environment determines genetic expression and as farmers and growers, all of you know this really well. You can have high quality seed and plant it into two different soil types, in two different environments and produce two completely different responses and two completely different plants. So think about what happens when you grow those two completely different plants and now you save seeds and plant seeds that were grown in a certain environment into a different environment yet again. You can very rapidly accelerate or very rapidly degenerate the integrity of a specific genetic line. So genetic potential is carried inside the seed but that is only potential. It’s still in its raw form.
Genetic expression and the way those genes express themselves in an environment is determined completely by the environment. So this is why on some vegetable crops you can have a variety that is, let’s say you have a variety of pumpkin that is powdery mildew resistant. Yet when you plant it into some environments it is still going to have powdery mildew, and that is because it’s not a genetics problem. It’s an environmental problem and when we talk about plant production in terms of the environment, that environment determines genetic expression, we have to ask the question okay, what is the environment in the context of a plant? There is obviously air, sunlight, water, sunshine and so forth. The major pieces that mediate a plant’s responses and buffer a plants response to climate extremes and to the rest of the environment is the mineral nutrition and the mineral integrity of that crop. So what epigenetic means is environment determines genetic expression.
When talking with plant breeders and geneticists corn is one of the crops that is extremely well understood and one of the reasons why I’m going to use it as one of the main examples in this discussion because of the amount of research that has been done on it. Corn geneticists will tell us that all the corn varieties available in the marketplace have the inherent genetic capacity to produce 1100 bushels per acre, and you go wait, what? The United States average for all US production right now is 157 bushels per acre, about 18% of that number. If you look at cherries, the genetic potential is for 20,000 pounds per acre, actually I think it’s even greater than that. Tomatoes, 180,000 pounds per acre, we’re actually now working with greenhouse tomato growers who are pushing this number. 90 tons of tomatoes per acre, that’s a tremendous potential. On field scale production, we’re consistently only harvesting a very small fraction of that.
Looking at sweet corn production, when we plant the same seed of the same variety onto bare ground, a bare ground environment will produce 800 dozen per acre. If you plant that same variety into plastic culture with drip irrigation and everything is identical with the addition of consistent watering, the yield per acre will double because it increases the number of ears per plant.
So the way this happens is that we have this gradual yield loss throughout the entire growing season. For example, the moment a corn seed with a genetic capacity to produce 1100 bushels per acre is planted, let’s say it’s planted into cold wet soil and now it drops down to 800 bushels per acre because of the stress that that seedling incurred. Perhaps the seed was planted too deep and had to struggle to emerge and now you reduce the number down to 750 bushels per acre. Perhaps nutrients were not placed correctly to allow that plant to really take off and grow and now you reduce it down to 650 bushels per acre. Whatever it is, I am making up the numbers. The numbers are not even relevant.
The point is that every single time stress is placed on a seed or on a plant that plant’s future harvest potential is being reduced and further reduced to the point at which you harvest the crop, you’re harvesting only a fraction of what you originally started with. So what this means is that when we get a yield response from something that we do, putting on a foliar application of nutrients, cultivation, pruning, whatever the case might be, we have not increased yields. We’ve simply kept those yields from being lost, because the seed had that original raw potential in it the day that it was planted. And so for us as growers, the framework for thinking of yield and quality increases is all about answering the question, how do you reduce stress or buffer stress? Because when you can reduce or buffer out that stress you allow that plant to keep more of its inherent genetic potential all the way through the season.
So as we look at plant development and growth through the season we see this expansion/contraction cycle that happens all the time. This is actually the first time that I am presenting this information quite in this way and it’s something that we take into consideration all the time when making our recommendations on the farms that we work on. So in all plant growth you have this constant expansion/contraction cycle, male energy, female energy. First…both are always present. There’s always both male and female energy present inside a plant but they alternate in terms of which is dominant. First male energy is dominant, then female energy is dominant, and so you can imagine a seesaw where it’s constantly moving back and forth from one to the next throughout the entire growing season.
So all plants have these cycles and they usually have many more than what we might think of. So these various expansion/contraction cycles of male and female energy are the foundation for a concept that we call critical points of influence. There are two types of critical points of influence. The first type is right at the peak moment of each cycle and the second type is at the shift from the vegetative cycle to the reproductive cycle and I want to describe what these look like. So how many cycles do you think a corn plant would have? How many shifts from vegetative to reproductive, back and forth if you had to guess? Any guesses?
So usually the initial reaction is to say, well a corn plant is vegetative until it starts silking and tassling and then it goes reproductive for the rest of the season. That’s the initial reaction but in reality there is a lot more happening than that. Actually a corn plant will have 13 transitions from one to the next. So first there is the embryo determination when the number of ears per plant is being determined, then there is the cycle when the number of rows in that ear is being determined. Two cycles later the number of kernels in each row are being determined, and then the tassel and the blossom are being developed, then there’s pollination, then we have endosperm development when the embryo within that seed is actually maturing and filling. And so that’s just the reproductive side, those are all sandwiched by vegetative parts of the reproduction cycle.
So if we look at trees as an example, most spur bearing trees will have six major macro cycles, there’s a few other smaller cycles as well but it begins in the spring with blossoming and pollination. The first thing in the spring trees bloom and pollinate so there is this very strong reproductive flush. As soon we have blossom and pollination complete then they initiate shoot development, now it switches to vegetative growth. So first there is a reproductive growth cycle, after which it switches to vegetative growth which is male energy, then it switches back to reproductive female energy by beginning to set the buds and bud initiation for next year’s crop.
Both of these energies arena they switch back and forth as to which is dominant at a given time in the growth period. These cycles can be measured by cytokinin and oxin balances, and hormone balances and you can visually observe how the plant is expressing itself as well. For example if you observe root system and reproductive system flushes, you can see it happening.
From bud initiation we switch to fruit fill and when you think about it, initially you might expect fruit fill to be reproductive but actually fruit fill is vegetative because it is expansion energy and you’re really filling that fruit. And then it switches to senescence when that tree begins senescing in the fall and dropping leaves which is again contraction energy where all the energy is being withdrawn from the leaves back into the tree. And then that energy that is withdrawing from the tree is now put out again to build and to fill spur buds for next year’s spring leaf development. So we have this cycle happening with these trees. Now the interesting part is what happens at different stages of this transition and this is something that…it’s a little bit hard for me to describe what this looks like in the field but I can describe the effects of what happens when we understand this in the field. So the first piece is that when we have a lack of nutritional integrity or environmental stress at the peak moment of each cycle, it sabotages yield potential.
I was describing earlier that yield drop happens when there is inadequate nutrition to support embryo development, particularly at the top of the reproductive cycle. When we have nutrient imbalances at the top of the reproductive cycle it has a much bigger impact than when we have nutritional imbalances at the top of the vegetative cycle. This is the foundation of why we have blossom abortion on peppers or poor pollination on cucurbit crops, almost any reproductive challenges.
Let’s take a cantaloupe plant for example, most cantaloupe genetics today will produce eight to ten female blossoms. Some varieties under really good management will produce as many as twenty two to twenty five female blossoms on every plant. So that is the genetic potential contained within the seed, which means the plant is telling us it has the inherent genetic potential to produce eight to ten melons per plant.
But when that plant doesn’t have the right nutrition or enough nutrition to support those reproductive parts of the plant, we either have poor pollination, or we have blossoms that abort before they ever open and have the chance to pollinate, or we have abortion after pollination. All of those things are a result of nutritional deficiencies happening at these specific stages.
One of the things that we have become known for is helping to consolidate fruit set. So on blueberries for example, it’s very common for us to see an entire blueberry harvest all blossom and pollinate within about a two to a three week window. For some producers, if they wanted an extended harvest window, that can actually be a challenge, but that’s one of the things that happens as plants become very healthy and very vigorous. You tend to get a much more concentrated fruit set.
But now the other interesting piece is when you have a lack of nutritional integrity at the transition from vegetative to the reproductive, it actually triggers proteolysis inside that plant which creates disease and insect susceptibility. This only happens in the transition from vegetative to reproductive. It doesn’t happen the other way around. It does not happen when you have the transition from reproductive to vegetative.
This ties back to nutritional integrity. The reason this happens is when those plants have enough nutrients to support that switch, they will begin sabotaging themselves. Let’s go back to the tree fruit example. If you have tree fruit such as a cherry tree or an apple tree that begins blossoming and blooming in the spring, you have blossoming and pollination and then at the end of pollination you get leaf emergence concurrently with pollination. That window is the window of greatest disease and insect susceptibility by a factor of 10X easily. Those trees are more susceptible to diseases and insects in that initial five week window after they begin pushing buds than they are at any other time of the year and the reason for that is, when you have all these blossoms pollinating on a tree it’s the equivalent of a pregnancy. There is a tremendous hormonal shift that happens inside that tree in a matter of three to four days. That hormonal shift is extremely dependent on being supported by calcium and boron and other trace minerals and if the nutrition is lacking to support that hormonal shift, that tree switches to proteolysis which means protein break down and it becomes extremely susceptible to diseases and extremely susceptible to insects.
And I want you to stop and think for just a moment, when do we have the greatest level of scab infestation? When do we have the greatest challenges with codling moth? When do we have the greatest challenges with plum curculio? We can go down the entire list of all the diseases that these trees struggle with. 90% of the disease severity happens in that first five week window because that tree’s pregnancy has not been supported with the right nutrition.
So when that pregnancy has not been supported with the right nutrition, we can also contemplate the integrity of the seed within that fruit. What is it missing to be able to fully express itself and transfer that genetic information on to the next generation?
And this holds true for every crop that you are growing that reproduces by seed. It holds true for every single crop that you are growing to grow the fruiting body and the fruit of the seed. If you are growing kale or salad greens than none of what I’m talking about is relevant but short of that for any reproductive crop, these same cycles apply.
So if we switch back and look at corn as an example, I want to give a bit more detail here. So according to some research that was done at the University of Iowa in 1992, they determined that nine to 12 days after corn seed germinates it is determining the number of ear embryos. So we have embryo differentiation happening and what is called the V2 stage, that’s the first reproductive stage inside the plant. Then 14 to 21 days after germination…so you have a nine to 12 day window and then it switches back to vegetative. When it switches after that window, two days later, 14 to 21 day period it switches back to reproductive and reproductive dominance and now it determines the number of rows. 41 to 49 days later it determines the number of kernels per row and so when you look at this entire spectrum, these first three windows of reproductive development in a corn plant there’s several really interesting pieces that emerge.
The first is the narrowness of the window, so that first window is three days long. The second window is seven days long. You have a fairly narrow window and the point for developing plant integrity and reproductive integrity is that any level of stress that happens in that three day window is going to have a negative impact on that plant’s development and on seed development. So if you have a hail storm or cold wet weather, whatever happens in that three day window is going to suppress that plant’s future reproductive potential. Some of those things we can moderate and buffer against and then there are some elements that are outside of our control. The second interesting part is that the greatest level of yield potential is determined earliest in the plant’s life.
This is true for all crops that blossom and pollinate in a very condensed timeframe. Those crops include grains, small grains, corn, and tree fruit and more. You can see that when you can impact on the number of ears, you can have a much greater impact on yield potential than if you simply impact the number of rows or the number of kernels per row. You can have a much bigger crop response. That happens earliest in the plant’s life. That is a universal principle that we have found in all the crops that we have looked at that have this characteristic of blossoming and pollinating at the same time. Now when you have crops, what we refer to as the multiple fruiting crops, that blossom and pollinate over an extended period, such as tomatoes, peppers, and cucumbers, that can pollinate for an extended period of time this principle does not hold true.
So the key to reducing yield loss we simply need to reduce stress at these critical points of influence or to buffer climatic stress. I’d like to give you an example just to describe what this can look like. Five or six years ago we started working with this farm called BioEnergetics Harmonics in Atlanta, Indiana. They are growing certified organic blue food grade corn that is used to make blue corn chips. We began working with them in 2012 and this was the very first year that we worked on the farm and it was an extremely dry spring. From the 1st of May to the 16th of July they had six-tenths of an inch of rain in this area. So this farm is surrounded by commercial commodity corn and the regional harvest average for the region on the fields that were actually harvested was 40 to 60 bushels per acre and that only happened on fields that were planted into a very narrow planting window. Anything that was planted after that window, that missed one of the rain falls, which was after the 1st of May, was never harvested at all. They just took it off the field as corn silage because it wasn’t going to make a grain crop at all.
This picture is a picture that was taken of that field on June 20th on the fifth day of ten days of a 100+ degree temperatures, so it was extremely warm, extremely dry and you can see that some of the leaves are beginning to curl a little bit. There is definitely some moisture stress happening on this crop and if you look at this on the far upper right of the picture you can see a slight different color green and that is from the field directly across the road and that’s what this field looked like. So at harvest time, and just as a frame of reference, this particular variety of blue corn is known to be generally a lower yielding variety and farmers in the Mid-West are consistently doing about 100 to 105 bushels per acre. This farm had been growing this variety for four years prior to when we started working with them and they had a four year average of 110 bushels per acre of this variety. So in 2012 they did 170 bushels per acre in the drought when all the other surrounding farms had a complete crop disaster. The historical average test weight over the prior four years was 56 and a half pounds per bushel and in 2012 that test weight jumped to 59.1 pounds per bushel. So this was extremely high quality seed and a substantial yield bump, 50% higher yields than anything that they had experienced before. This was the first instance in which we started trying to deeply understand what was happening that evolved into the concept and into the idea of critical points of influence.
What happened on this corn crop? How was it possible that all the surrounding farmers had a crop disaster? On this farm the historical yield averages increased by a factor of 50%. How does that happen? This is a certified organic farm. They incorporated a cover crop of oats before the corn crop was planted and we put together a nutritional solution that was applied in furrow at planting and we followed up with three foliar sprays. We originally only intended to do two foliar applications but we did one foliar application at the V4 stage which is the stage when it’s determining the number of rows per ear that is it going to have. We did a second foliar application at the V6 when it’s determining the number of kernels and then the third foliar spray that we had not planned on, on day three of that ten day window of a 100+ degree temperatures. So we put on the starter application and three foliar applications of nutrients. That was the only thing we did the entire growing season and those four applications of nutrients were enough to give that crop a tremendous resilience against the moisture stress.
When you give a plant really strong nutrition and its reproductive energy becomes super charged then you will see bud expression on some crops that you have not observed before that you might think is very abnormal. So take cucumbers for example, we usually think that cucumbers are supposed to have one bud per node. Commercial growers like to see one female blossom at every leaf node and we have photos of growers that we have worked with where they have two or three cucumbers on every node all the way across the entire plant and they’re not just blossoms. They’re maturing, they’re filling these cucumbers. This is an incredible fruit load.
There certainly are genetic characteristics here as well because some genetics will do this much more easier than others. In peppers for example it is relatively easy to get chili peppers to get three to four blossoms per node and three to four fruit per node all the way through to harvest. That doesn’t happen as easily with bell peppers or hot peppers for example. So there are genetic characteristics that come into play, but as a general rule, what we have observed is when you give plants really strong nutrition, their reproductive potential begins expressing itself to a new degree that we don’t even consider as being normal because we almost never get the opportunity to see it. Most of us here in this room have no idea what a really healthy plant actually looks like.
Alright I got completely side tracked from where I was going. Okay so what happened with this corn crop? I think there were three main pieces that happened that we didn’t just have a direct impact on this plant’s reproductive potential but we had an indirect impact to buffer out and mediate climate stress that was actually much bigger than the direct impact that we had. So the indirect impact was threefold. The first is that when a plant has good nutrition, particularly when it has good potassium levels and good trace mineral levels, then it has the capacity to regulate the stomata and it loses a lot less water from respiration.
So I think these plants were much more water efficient right from the get go. Secondly if I go back to these pictures, there’s a little bit of sunlight glare in this picture but you can still see how these plants have a glossy waxy sheen. That glossy waxy sheen on these leaves is a result of very strong lipid expression. These plants have extremely high fat concentrations and these high levels of fats and oils inside the plant result in a waxy layer on the leaf surface. That one of the indicators that we use in the field to evaluate plants and to observe that plants have an extremely high energy level because a plant has to have a surplus of energy to store high levels of fats, exactly the same way that we do. We don’t store fats, animals don’t store fats unless they have a surplus of energy. Plants do the exact same thing. When they have a surplus of energy, they store the surplus in the form of fats and oils.
So these plants had a surplus of energy. They had high oil concentrations and high wax layer on the leaf which again resulted in better water use efficiency. But the best part of all was the change in these plant’s root systems. And the change in the root systems did not come about because of the fertilizers that were applied to the soil. They came about as a result of the fertilizers that were applied as a foliar, that had nothing to do with root system development directly. When you have extremely high test weight corn, the only way for that to happen is for that plant to have extremely high nutrient availability late in the growing season when it is filling that grain. It doesn’t matter how good of a job you do of growing a great corn plant. It doesn’t matter how good pollination you have. When you actually begin filling grain, you have to have extremely high levels of available nutrients to fill that grain at that period or you will end up with low test weight grain. And we saw a substantial jump in test weight gains and yet the soil was still really dry. We had had some rainfall by that point but it was not generous by any measurement.
We refer to this stage of corn development as the framing stage and the framing stage describes what is happening within the plants in terms of carbohydrate transport and how they’re moving sugars around. A moment ago I made a comment that most of us in this room don’t even know what a really healthy plant actually looks like. To give you a frame of reference for what I was talking about, every square inch of a leaf has a finite photosynthetic capacity. That is based on the speed of all the biochemical pathways, the number of chlorophyll concentration, the number of cells, the number of chloroplast etc. but there is a finite limit to photosynthetic capacity. Let’s call that number 100%. Most plants only photosynthesize in the neighborhood of 18 to 22% of their inherent photosynthetic capacity. So think of what could happen if you could move that plant from 20% photosynthetic efficiency, all the way up to 60%. You’ve just tripled the amount of sugars produced in every 24 hour photo period. So all of a sudden what we think of as normal basic plant physiology completely changes.
So what happens is that during each day’s twenty four hour photo cycle, we have peak photosynthetic activity and in that peak we have sugar formation in the chloroplast, in the cells, inside the leaf. Then starting in late afternoon those sugars begin to be transported out of the leaves, the photosynthetic factories and moved to the sugar sinks. There are three basic sugar sinks inside plants. There is the new shoot growth at the top of the plant, there is the root development and then there is the fruit. So these sugar sinks are very different in terms of the way plants behave with them. If you look at a plant’s total sugar production over the entire growing season you have a total of 100%. That total of 100% over the course of that plant’s entire life is going to be divided into four almost exactly equal pieces.
25% goes into fruit above the soil, 25% goes into vegetative biomass above the soil. Below the soil 25% goes to root system, 25% goes to root exudates. This only happens when plants cross the threshold of 60% or greater of photosynthetic efficiency. If you don’t have that level of photosynthetic efficiency then that number changes and the total volume changes of course and the division changes as well where now you have a much higher proportion that goes into vegetative biomass and fruit. Somewhere in the order of about 70% and only 30% ends up below the soil surface.
But what happened in the case of this corn? So that sugar division of 25, 25, 25, 25 doesn’t all happen equally at the same time. There is one stage that we call the framing stage where the majority of the sugars produced in every 24 hour photo period go down to the root system and out through the root system as root exudates.
So the framing stage, the stage when you have a corn plant that is 18 inches tall or a tomato plant that is 16 inches tall, for many of these annual crops, the framing stage happens about six to eight weeks after being planted. So let’s say you have a tomato plant that is twelve inches tall. It took that tomato plant six weeks to get this big, in the next six weeks that plant is going to get this big. There is a tremendous amount of biomass growth that happens very, very quickly. Our first inclination is to think well the majority of the sugar production is going into vegetative biomass at that point but that’s actually not the case. During that framing stage every day, every 24 hour photo period, as much or even greater, somewhere in the neighborhood of 70 to 80% of the total sugar production every day goes down to the root system, out through the root systems as root exudates to feed soil biology.
This is a well-researched number. It’s reported in Horas Marshner’s book, Mineral Nutrition, Higher Plants and a number of other references. Horas Marshner’s book or now Petra Marshner has edited the last version, is used to teach plant physiology today in most major universities. So when I first read that number 70% of the total sugars going out through the root system as root exudates, the first question that went through my mind is why would a plant waste that much energy? And in reality what is happening is that plant is not wasting its energy at all. It is building a reserve bank account that it can then tap into later in the growing season. So what happened is we were able with foliar applications to keep this corn crop still actively growing in 100 degree dry temperatures and to keep it actively photosynthesizing and transmitting sugars down into the root system so that later, ten weeks down the road when we reach the grain fill stage, it was able to tap into those microbial metabolite reserves that it accumulated in the root system and use that to produce extremely high test weight grain. This is the really fascinating part for me. Plants can access microbial metabolites and use them as a source of nutrition in the absence of water in the soil profile.
They are not dependent on free water anymore. If we can get a crop off to a strong early establishment and build a strong microbial community in the root system and in the soil profile, you can actually develop a crop that has an extremely high degree of climate resilience. So when I talk about critical points of influence and using nutrition, a common response that I get is, ‘I have all these climate factors. I have extreme hot or extreme cold, too wet, too dry…I have all these things that are producing stress on my crop that I can’t control.’ Well, we can’t control them but what we can influence is the crop’s response to that stress. We can change the stress response by giving the crop the nutritional support and tools that it needs to be a lot more resilient.
So I’ve tried to describe the story as well as I can and of course what I haven’t told you because there’s way too much to tell you in an hour and 15 minutes is how do you do this? And there is just one very simple key which is complex in its simplicity and that is nutrient balance and mineral balance, not nutrient density, not total mineral supply, but simply mineral balance. And this sounds very simplistic and on the surface it is but it’s incredibly difficult to achieve. Five years ago in our consulting work, we started using plant sap analysis, which I’ll be talking about more tomorrow and when we started using sap analysis to evaluate the nutritional integrity of crops it was incredibly powerful tool. It’s the single most valuable tool that I have ever used and many consultants that use it say exactly the same thing because it is so accurate. It is so sensitive and it shows us so much and what it showed us was that one of our fundamental paradigms about plant nutrition was completely wrong. We have operated from the paradigm that we need to address deficiencies. It you have a zinc deficiency you put on zinc. If you have a phosphorous deficiency you put on more phosphorous. If you have a potassium deficiency you put on more potassium and what we learned using sap analysis is that the biggest problem with nutritional imbalances in agriculture are created by the excesses of products that the farmer applies and that the excesses create the deficiencies.
That is true for practically all of the micronutrients in many of the situations that we work on. So what we see happening over and over again is that we don’t in fact have a potassium deficiency. We have an excess of calcium that is creating a potassium deficiency. We don’t have a magnesium deficiency. We have an excess of calcium that is creating a magnesium deficiency. So if there is one point that I would like for you to remember from this it is simply that, when someone tells you that one specific nutrient is a very important for seed development and for fruit quality and for plant health, that is likely to be very true but you can create a lot of problems by addressing that one nutrient in the absence of others and we really have to address balance. So to summarize what we have observed is when you have plants that have 60% photosynthetic efficiency in every 24 hour photo period instead of only 15 or 20%, then the way that plant expresses itself changes. When we talk about environment determines genetic expression, I can tell you that when you take poor quality seed and you plant it into an optimum environment, the plant that will result is completely different from the plant that will result in a poor environment.
But then if you save the seed from that plant grown in an optimal condition with optimum nutrition and you plant that seed, there’s a very high likelihood the child seed will not perform comparably to the parent. It is going to outperform the parent substantially in ways that you may not be able to predict. Leaf shape may completely change or plant expression may completely change. This has nothing to do with hybridization or de-hybridization. It has nothing to do with open pollinated plants. It has nothing to do with original genetics. This happens across the board, but all of a sudden that plant’s expression can begin changing substantially and usually in our experience so far it has always been in ways that favored the farmer. There is tremendous power in having high quality seeds. So today in the fruit and vegetable industry, I’m going to speak very frankly and pull no punches. Today in the fruit and vegetable industry by and large we have atrocious seed quality because to the best of my knowledge I am not aware of any commercial seed production companies or seed growers at the moment who are focusing on producing premium quality seed by managing nutrition.
And this is one area in which I see a huge opportunity. There are many things that are happening in the biological and regenerative agriculture movement that are very positive and that are very powerful and this is one opportunity that is still a gaping hole. It’s a really big hole that we can still work on to fix. So I think I will stop there and open it for questions, for any questions that you might have. Yes?
Question 1: I wonder if you have a picture of one of those amazingly healthy plants none of us have ever seen?
John: Yes I do have dozens. Unfortunately we’re not using my computer to present. I will try to…I still have a couple presentations. I’ll put them in some of my presentations for tomorrow. I have pictures of cucumbers for example that have three to four buds per node. I have pictures of eggplant where the leaves are 14 inches wide and 21 inches long and many more.
Question 2: Hi, yeah thank you. You mentioned like the blue corn, you said the plants are not dependent on water as much, but I was wondering, is it because the exudates help feed the mycorrhiza and you get the water for the soil, cause I think if you have more pounds you have to have more water. So it just doesn’t seem to make sense that you say it’s not dependent on water as oppose to the mycorrhiza.
John: Very good question, I included one very key word in that phrase and I’m happy to clarify. They are non-dependent on free water and so what I mean by that is that within soil, soil appears dry and no longer has available water for the plant at 60% moisture. So there’s still 60% water in the profile but it is absorbed and adhered to the soil colloid structure so tightly that the plant roots cannot absorb it. But in that environment, in an environment that visually to our eye and to our hand feels dry, mycorrhizal fungi can still access that water which you mentioned and the plants are absorbing microbial metabolites. So they’re absorbing amino acids. They’re absorbing organic acids etc. which they can absorb without free water both because of the fungal and bacterial colonization on the rhizosphere and also because those nutrients are not water dependent. They’re not water soluble…they don’t have to be water soluble to move into the plant.
Question 3: You mentioned briefly an oat cover crop before this planting of blue corn. Is that critical to your rotation from the oat to the blue corn or can you expand on that planting of oats a little bit? And talking about mycorrhizal from the absorbed water. Did the oats…was that part of your inoculation?
John: Did the oats contribute to the yield response that we got? I believe absolutely yes, they did, and that if we had not had the oats cover crop we would’ve had much less mycorrhizal colonization and we would’ve had poorer soil structure with not as good moisture holding capacity. So the one interesting part was that on the 1st of May, I said that between the 1st May and July 16th we had six tenths of an inch of rainfall. Just prior to that there was about an inch of rain at the end of April and on the corn field that you saw across the street, the majority of that inch of rain ran off. On this field it did not run off. It soaked into the soil. So I think in that context the oats cover crop was very critical. But there is another piece as well that we have discovered since this happened four years ago. In the last two years we have been doing a lot of research and trying to understand what it takes to produce a disease suppressive soil. And this is an entire three hour presentation in and of itself. It’s way more than we can get into in this moment but there is a very specific set of parameters, biochemistry parameters and soil biology parameters that define a soil that actively antagonizes disease organisms. That completely eliminates fusarium and verticilium and rhizoctonia and Pythium and vitofurium. They do not have the chance to reproduce, which is incredibly powerful. And so we have been doing a lot of research and trying to understand how can we create that type of soil environment on the farms that we are working on and we have discovered that oats as a cover crop are one of the key cover crop mechanisms that help produce a disease suppressive soil environment. So I think there were possibly multiple things going on. That cover crop also contributed to the success absolutely.
Question 4: A lot of people focus on the seeds, I actually focus more on trees and I would agree with you that the quality of trees that you can buy or something is unbelievably you know. But going forward, you know what do you do for good tree stock? I mean it’s not easy.
John: Okay so the comment was that looking at this from a perspective of growing trees the quality of seedlings that are available is also extremely poor and I completely agree. It is atrocious and we do some consulting work on some of these nurseries and I can tell you that they deliberately withhold nutrients and they deliberately withhold water to keep these seedlings small because otherwise they have to spend a lot more time and effort and energy digging them out, pruning them and shipping them. So I’ve always had a fairly heretical perspective on how extremely high quality seedlings should be produced in an orchard system. The last two years we have been working with a cherry orchard that has given us the opportunity to really demonstrate what we’re talking about. So what we are doing today on this cherry orchard is growing the trees in place. We are buying the root stock seedlings when they are just small whips, 9 to 10 inches tall, and growing them for one year. We are giving optimum nutrition, foliar feeding them, irrigating them. They get compost applications. They get everything that a tree could possibly desire. It’s absolutely an optimum environment, as optimum as anything can be out of doors. They grow extremely rapidly, from being planted in late April or early May to August our target is to have a stem calliper, three quarter inch in diameter. Then we graft on a sleeping eye bud at the base of that plant for whatever variety we want and then the following spring we clip off the root stock and we put all the energy into one bud. We have already done this on one block that is I think six acres.
We’re doing a second block that was grafted this August and will now be growing from the bud next spring. This is being done in high density cherry trees that are being planted six feet apart. And based on our first year experience, the second year we think is going to be even better because we’ve learned some different management techniques. We believe that in our second year we are going to completely fill the tree row and we’re going to have a solid row of trees the second year and we will have a full harvest the third year. Instead of trying to hold these trees back we are pushing them but we are not pushing them using nitrogen and synthetic forms of fertilizer. So they are growing extremely rapidly and they are extremely high quality at the same time. This is completely changing the perspective of the entire cherry growing industry in the Pacific North West because they usually expect to have their first harvest six years after planting and we’re talking about a full 100% harvest three years after planting. And right now we have all the preliminary evidence to indicate that that is going to be a very strong probability.
Question 5: Hi, I just wanted to know how you feel about no-till and how important it is with respect to holding on to the mycorrhizal fungal networks and have you done any work to try to figure out how to plant after a cover crop like oats or other cover crops without actually tillage and done any side by sides or have any feelings on that?
John: I’m going to specifically answer your question in the context of mycorrhizal fungi, just excluding the entire conversation about all the other benefits or potential challenges of no till, just purely in the context of mycorrhizal fungi. Mycorrhizal fungi are completely dependent on a living root system. It has to be alive. It has to be actively growing. What we have observed is that mycorrhizal fungi can and do survive tillage when you go from a growing crop to a growing crop. In other words when you incorporate a cover crop and you plant seeds directly into it several days later and you have rapidly growing root systems, those root systems will be colonized by mycorrhizal and they will keep on going. It’s when you have an extended period of a dead fallow period where there are no actively growing root systems, that the mycorrhizal population is going to crash very substantially. How long is that window? Because I know that’s the next question you’re going to ask, I don’t know. I don’t have the answer to that. We haven’t done enough research on it. We have definitely observed this to be the case and it varies with different soil types, sandier soils have a shorter window but I would say the window is usually in the neighborhood of about ten to 14 days. So it’s not immediate, you do have a short window that mycorrhizal fungi will still survive and if you would’ve asked me that question two years ago, I would’ve given you the exact opposite answer but in the last two years we have seen that to be true on enough farms that I know it is accurate.
Question 6: The soil mycorrhiza and everything you’ve been talking about, I’m assuming that is not possible if they’re using glyphosates or salt fertilizers?
John: Well definitely many of the materials that are used in commercial agriculture glyphosate, herbicides, fungicides, seed treatments, fertilizers etc. tend to have a very suppressing effect on soil biology and they can definitely prevent mycorrhizal colonization and they don’t fit into a biological system.
Question 7: Specific but you mentioned that if increased nutrients increases regulation of stomata and I’m just wondering what exactly….what is the stomata doing differently than one that has a plant that’s not very well nutrients?
John: So in particular the key nutrient for stomata regulation is potassium. Potassium is very strongly connected to osmo regulation and so basically it facilitates a faster plant response. So faster opening and closing of the stomata, so what that means is that during the 24 hour photo cycle, it manages the signal between respiration and photosynthesis pathways much faster and the short answer is that the stomata is open for a much shorter period of time. So you’ll lose a lot less water.
Question 9: The photosynthesis capacity goes down then right?
John: The question was, does the photosynthesis capacity then also go down and the short answer is yes. You have this balance between photosynthesis and photo respiration. When you have a plant stress response in a high temperature environment you have the potential for greater levels of photorespiration which is…this is not technically correct but in terms of plant growth patterns you could almost say that it is the opposite of photosynthesis. So in these very high temperature conditions, when you have 100+ degree days, most of the plant’s sugar accumulation happens earlier in the morning and later in the day and the stomata are closed throughout the day. Also something very important in the context of corn in particular that corn being a C4 photosynthetic pathway continues to photosynthesis in much higher temperature. C3 pathway plants such as tomatoes and cantaloupe for example, cap at 86 degrees Fahrenheit. They don’t continue to photosynthesize past that point. In terms of carbon, sequestration and photosynthesis, there are three ecosystems which exceed all other ecosystems capacity to sequester carbon by a substantial margin. The first is a young growth coniferous forest, an evergreen forest that is growing very rapidly will sequester carbon faster than any other ecosystem. The second is perineal polyculture that is being intensively grazed with intensively managed rotational grazing and the third is corn. It is actually possible to build soil organic matter while we are growing corn. It’s been proven on many farms. The simple premise that corn is a crop which extracts carbon from the soil and contributes to soil degradation is true because of the way that we have screwed it up. It isn’t inherently and automatically true.
Question 10: Just to add to that, so that’s not corn every year right,
John: That is corn every year. We only have five years of data at this point. We have five years of data where on dry land corn in Kansas, so we’re talking ten to eleven inches of annual rainfall, we have seen soil organic matter increase from a baseline level of one and a half percent, all the way up five and a half percent in five years. You can imagine what that does for water absorption capacity.
Question 11: I hope their neighbors are paying attention to all this.
John: It’s really risking in the corn crop. You can’t spend any money. I’m being facetious.
Question 12: John your concluding statement that mineral balance is really the key to all this, what are the implications for us as farmers in terms of supplementation then? You know a lot of times there’s recommendations and we can’t apply what we need to apply because of cost or whatever so we choose to go a more cost effective root and apply you know, the most efficient nutrient for instance. But to your statement that would be throwing us out of balance. So just in general, how do we move forward with mineral balancing where mineral balancing is so critical and so easily disrupted?
John: So very, very good question. The easy answer is that you hire Advancing Eco Agriculture to help you figure it out. So when I think about the consulting work that we do as a company and how we address these challenges on a farm, kind of there’s a couple of different pieces. Okay as a starting point we operate from the premise of that the plant is the report card, not the soil test which is fundamentally at odds with the way organic and biological agriculture have approached plant nutrition.
So historically nutrient recommendations were made based on a soil analysis and I’m not saying that soil analysis doesn’t have any value because it does, but soil analysis is still an imperfect science. However, as growers, we have to get results and far too many times, over and over again, we would use soil analysis and make recommendations based on the soil analysis and we would fail to get results and I know that for many of you farmers, you probably have experienced that. You don’t see the crop response that you would like to see. So we changed that and we started looking and considering the plant to be our report card. We still use the soil analysis to try to help us understand what is happening and what is going on but we use the plant as an indicator of what we should apply and what we should not apply. Tomorrow I want to talk about sap analysis and how we do this but then the second part is that we are trained to address the deficiencies.
And we have said that that cannot be the first rule, it has to be the second rule. The first priority is to address the antidote to the excesses. So let’s say you have a soil that says that you have high levels of magnesium and low levels of calcium and high levels of potassium. I’m just making up a scenario. The historical approach would have been to say okay, magnesium and potassium are adequate and calcium is low therefore we need to add calcium. When in fact we get the biggest crop response when we don’t…I’m not saying we shouldn’t add calcium but I’m saying that’s a number two priority. The number one priority is to put on the antidote for the high potassium and the high magnesium and that might be calcium in some soil types. In some soil types it might be sulphur and in all soil types, regardless of soil type, whenever you have high potassium it will be manganese because manganese will down regulate the absorption of potassium. The number one priority needs to be to suppress the excesses and only the number two priority to address the deficiencies for all of the macro nutrients, for all the major elements, calcium, magnesium, potassium, sulphur, phosphorous and so forth. For the trace minerals that does not hold true, for boron, zinc, manganese, copper, iron etc. when you do have a deficiency there then you need to address it and apply those deficiencies.
Now what has set us apart as a company at Advancing Eco Agriculture is that we do not consider soil amendments as a primary way to produce a crop response. It’s very secondary. Our biggest emphasis and what we work with the most is with foliar applications of nutrients. We don’t want to continue applying nutrients every year, year after year to rebuild our soil. Foliar applications of nutrients are the most economical way to produce a substantial crop response so that we can be more profitable, and foliar applications of nutrients are also the fastest and most economical way to build soil health. The exact contrary of what we’ve been taught, because when you use foliar applications of nutrients and you help plants increase their photosynthesis level you are not only increasing yield and increasing quality but you are also transmitting a lot of root exudate out of the soil profile.
When you do the arithmetic and you calculate the amount of plant biomass per acre and if 25% of that…if you have the plant biomass per acre above the soil surface and 25% of that represents root exudates and 25% represents root biomass, 50% being below the soil surface. You very quickly realize that you can’t afford to put on enough compost to match that. So for the trace minerals, particularly all the metals, this would exclude boron, so for iron, manganese, zinc, copper and cobalt from our perspective those nutrients almost always must be addressed in foliars or at the very least in the form of liquids and not dry soil amendments. And this is again another conversation that ties into the concept of developing disease suppressive soils but all these metals, manganese and iron and so forth, exist in the soil in different oxidation states. So if you think about iron for example you can have an iron nail that is new and shining. You expose it to air and sunshine and water, it’s going to start rusting. That rust is oxidized iron. Plants cannot absorb oxidized iron. They can only absorb iron in what is called the reduced form and so the challenge is that when you apply 20 pounds per acre of manganese sulphate or 20 pounds per acre or 5 pounds per acre of copper sulphate or 6 pounds per acre of zinc sulphate, any of these trace mineral sulphates, when you apply them to the soil then there is…actually I need to adjust what I said for just a moment.
This is true for all the metals with the exception of zinc. This does work for zinc because zinc only has one oxidation state. For manganese and for iron and so forth, whatever you apply to the soil will not be absorbed by those plants in your lifetime because it has to be converted to the reduced form which takes very highly functioning soil biology. We had a farmer who very badly wanted this to not be true, very badly and he experimented with putting manganese sulphate, combining manganese sulphate with very high quality compost. He premixed the manganese sulphate with the compost with the intention that that biological activity should help the manganese sulphate release and he did test plots. 20 pounds, 40 pounds, 80 pounds, 160, 200, 400 pounds per acre manganese sulphate. On the sap analysis in terms of plant response and plant absorption, the manganese numbers did not change for three years and that’s still up to this day they haven’t changed. We don’t know what they will be next year but there has been zero crop response from those applications of manganese sulphate.
So for the trace minerals the most economical way to address trace minerals is to put on what this year’s crop requires, this year in a liquid form as foliar sprays or in the irrigation system and get a maximum crop response. And then the reality is that all the soil here in New England has 200+ pounds per acre of manganese already in the top six inches of the soil profile. That manganese can become available when you have an extremely aggressive microbial community and that happens when you get these really large root systems with a lot of root exudates. So what we have seen happening is that we’re putting on, in many case over the course of a season, we might be putting on ounces per acre of manganese to get a maximum crop response but then over a two year or three year period of doing that, all of a sudden it becomes unnecessary because the manganese on the soil analysis comes up all by itself way more than what we have applied. It’s not a linear mathematical equation at all.